private void _Refresh(LinkClient client, IEnumerable <int> groups = null)
{
/* Require lock */
var cid = client._id;
var set = _joined.GetOrAdd(cid, _ => new HashSet <int>());
foreach (var i in set)
{
_set.TryGetValue(i, out var gro).AssertFatal("Failed to get group collection!");
gro.TryRemove(cid, out var val).AssertFatal(val == client, "Failed to remove client from group collection!");
if (gro.Count > 0)
{
continue;
}
_set.TryRemove(i, out var res).AssertFatal(res == gro, "Failed to remove empty group!");
}
if (groups == null)
{
/* Client shutdown */
_joined.TryRemove(cid, out var res).AssertFatal(res == set, "Failed to remove group set!");
_clients.TryRemove(cid, out var val).AssertFatal(val == client, "Failed to remove client!");
return;
}
// Union with -> add range
set.Clear();
set.UnionWith(groups);
foreach (var i in groups)
{
var gro = _set.GetOrAdd(i, _ => new ConcurrentDictionary <int, LinkClient>());
gro.TryAdd(cid, client).AssertFatal("Failed to add client to group collection!");
}
}
private async Task <Task> _AcceptClient(Socket socket)
{
LinkError _Check(int id)
{
if ((Links.Id < id && id < Links.DefaultId) == false)
{
return(LinkError.IdInvalid);
}
if (_clients.Count >= _climit)
{
return(LinkError.CountLimited);
}
return(_clients.TryAdd(id, null) ? LinkError.Success : LinkError.IdConflict);
}
var key = LinkCrypto.GetKey();
var blk = LinkCrypto.GetBlock();
var err = LinkError.None;
var cid = 0;
var iep = default(IPEndPoint);
var oep = default(IPEndPoint);
byte[] _Response(byte[] buf)
{
var rea = new Token(LinksHelper.Generator, buf);
if (string.Equals(rea["protocol"].As <string>(), Links.Protocol, StringComparison.InvariantCultureIgnoreCase) == false)
{
throw new LinkException(LinkError.ProtocolMismatch);
}
cid = rea["source"].As <int>();
var mod = rea["rsa"]["modulus"].As <byte[]>();
var exp = rea["rsa"]["exponent"].As <byte[]>();
iep = rea["endpoint"].As <IPEndPoint>();
oep = (IPEndPoint)socket.RemoteEndPoint;
err = _Check(cid);
var rsa = RSA.Create();
var par = new RSAParameters()
{
Exponent = exp, Modulus = mod
};
rsa.ImportParameters(par);
var packet = LinksHelper.Generator.Encode(new
{
result = err,
endpoint = oep,
aes = new
{
key = rsa.Encrypt(key, RSAEncryptionPadding.OaepSHA1),
iv = rsa.Encrypt(blk, RSAEncryptionPadding.OaepSHA1),
}
});
return(packet);
}
try
{
var buf = await socket.ReceiveAsyncExt().TimeoutAfter("Listener request timeout.");
var res = _Response(buf);
await socket.SendAsyncExt(res).TimeoutAfter("Listener response timeout.");
err.AssertError();
}
catch (Exception)
{
if (err == LinkError.Success)
{
_clients.TryRemove(cid, out var val).AssertFatal(val == null, "Failed to remove placeholder!");
}
throw;
}
var clt = new LinkClient(cid, socket, iep, oep, key, blk);
_clients.TryUpdate(cid, clt, null).AssertFatal("Failed to update client!");
clt.Received += _ClientReceived;
clt.Disposed += _ClientDisposed;
return(clt.Start());
}