public override byte PerformHandshake(byte[] tag, H2NBinaryWriter response, IPEndPoint address, byte[] peerIdWanted)
{
var peerIdWantedStr = peerIdWanted.BytesToString();
var sessionWanted = Sessions.Values.SingleOrDefault(x => x.Peer.IdStr == peerIdWantedStr);
if (_pCirrus != null)
{
var session = Sessions.Values.SingleOrDefault(x => x.Peer.Address.Equals(address));
if (session == null)
{
FATAL("UDP Hole punching error : middle equivalence not found for session wanted");
return 0;
}
var request = (session as Middle).Handshaker;
request.Write((byte)0x22);
request.Write((byte)0x21);
request.Write((byte)0x0F);
request.Write(sessionWanted == null ? peerIdWanted : (session as Middle).Peer.Id, 0, 0x20);
request.Write(tag);
return 0;
}
if (sessionWanted == null)
{
Debug("UDP Hole punching : session {0} wanted not found", peerIdWantedStr);
var addresses = new List<IPEndPoint>();
if (addresses.Count == 0) return 0;
var first = true;
foreach (var _address in addresses)
{
response.WriteAddress(_address, first);
first = false;
}
return 0x71;
}
if (sessionWanted.Failed())
{
Debug("UDP Hole punching : session wanted is deleting");
return 0;
}
byte result = 0x00;
if (_middle)
{
if (sessionWanted.Target != null)
{
var attempt = HandShakeSession.GetHelloAttempt<HelloAttempt>(tag.BytesToString());
attempt.Target = sessionWanted.Target;
HandShakeSession.CreateCookie(response, attempt, tag, "");
response.Write(sessionWanted.Target.PublicKey);
result = 0x70;
}
else
{
FATAL("Peer/peer dumped exchange impossible : no corresponding 'Target' with the session wanted");
}
}
if (result == 0x00)
{
/// Udp hole punching normal process
var times = sessionWanted.GetHelloAttempt<Attempt>(tag.BytesToString()).Count;
sessionWanted.P2PHandshake(address, tag, times, (times > 0 || address.Address.Equals(sessionWanted.Peer.Address.Address)) ? Sessions.Values.SingleOrDefault(x => x.Peer.Address.Equals(address)) : null);
var first = true;
foreach (var ipEndPoint in sessionWanted.Peer.Addresses)
{
if (ipEndPoint.Equals(address))
WARN("A client tries to connect to himself (same {0} address)", address);
response.WriteAddress(ipEndPoint, first);
Debug("P2P address initiator exchange, {0}:{1}", ipEndPoint.Address, ipEndPoint.Port);
first = false;
}
result = 0x71;
}
return result;
}
