/// <summary>
/// 将buffer的前3个字节，解析到 TunnelPacket 中
/// </summary>
/// <param name="buffer"></param>
/// <param name="offset"></param>
/// <param name="packet"></param>
public static void Deserialize(byte[] buffer, TunnelPacket packet)
{
packet.Length = ((buffer[1] & 0x3f) << 8) | buffer[2];
packet.Type = (TunnelPacketType)((buffer[1] >> 6) | (buffer[0] & 1) << 2);
packet.Version = (0x7 & (buffer[0] >> 1));
packet.Magic = buffer[0] >> 4;
}
/// <summary>
/// 将buffer的前3个字节，解析到 TunnelPacket 中
/// </summary>
/// <param name="buffer"></param>
/// <param name="offset"></param>
/// <param name="tunnelPacket"></param>
public static void Deserialize(byte[] buffer, TunnelPacket tunnelPacket)
{
((IPacket)tunnelPacket).Reuse(((buffer[1] & 0x3f) << 8) | buffer[2]);
tunnelPacket.Type = (TunnelPacketType)((buffer[1] >> 6) | (buffer[0] & 1) << 2);
tunnelPacket.Version = (0x7 & (buffer[0] >> 1));
tunnelPacket.Magic = buffer[0] >> 4;
}
public void ReceiveTunnelPacket(G2ReceivedPacket raw, TunnelPacket tunnel)
{
if (Core.InvokeRequired) // called from lookup core's thread
{
Core.RunInCoreAsync(delegate() { ReceiveTunnelPacket(raw, tunnel); });
return;
}
Debug.Assert(!IsLookup);
if (IsLookup)
{
return;
}
// decrypt public packet
if (Core.Sim == null || Core.Sim.Internet.TestEncryption) // turn off encryption during simulation
{
if (tunnel.Payload.Length < 16)
{
throw new Exception("Not enough data received for IV");
}
tunnel.Payload = Utilities.DecryptBytes(tunnel.Payload, tunnel.Payload.Length, LocalAugmentedKey);
}
G2ReceivedPacket opPacket = new G2ReceivedPacket();
opPacket.Root = new G2Header(tunnel.Payload);
// set source information
if (G2Protocol.ReadPacket(opPacket.Root))
{
opPacket.Source = new DhtAddress();
// used to add direct op contact if source firewall is open
// or re-routing through same lookup proxy
opPacket.Source.IP = raw.Source.IP;
opPacket.Source.UdpPort = raw.Source.UdpPort;
// op user/client set by net/comm processing
opPacket.Source.TunnelClient = tunnel.Source;
opPacket.Source.TunnelServer = tunnel.SourceServer;
PacketLogEntry logEntry = new PacketLogEntry(Core.TimeNow, TransportProtocol.Tunnel, DirectionType.In, opPacket.Source, opPacket.Root.Data);
LogPacket(logEntry);
IncomingPacket(opPacket);
}
}
// nodes in lookup proxy mode are psuedo-open, instead of udp they send tunneled packets
// tunnel packets include routing information to the lookup target as well as
// the encrytped operation packet embedded in the payload
public int SendTunnelPacket(DhtAddress contact, G2Packet embed)
{
Debug.Assert(contact.TunnelClient != null && contact.TunnelServer != null);
Debug.Assert(Core.Context.Lookup != null);
Debug.Assert(!IsLookup);
Debug.Assert(Core.User.Settings.OpAccess != AccessType.Secret);
if (IsLookup ||
Core.Context.Lookup == null ||
Core.User.Settings.OpAccess == AccessType.Secret)
return 0;
OpCore lookup = Core.Context.Lookup;
// tunnel packet through lookup network
byte[] encoded = embed.Encode(Protocol);
PacketLogEntry logEntry = new PacketLogEntry(Core.TimeNow, TransportProtocol.Tunnel, DirectionType.Out, contact, encoded);
LogPacket(logEntry);
TunnelPacket packet = new TunnelPacket();
// encrypt, turn off encryption during simulation
if (Core.Sim == null || Core.Sim.Internet.TestEncryption)
packet.Payload = Utilities.EncryptBytes(encoded, GetAugmentedKey(contact.UserID));
else
packet.Payload = encoded;
packet.Source = new TunnelAddress(lookup.Network.Local, Core.TunnelID);
packet.Target = contact.TunnelClient;
int bytesSent = 0;
// if we are the tunnel server (our lookup net is open, but op is blocked)
if (lookup.Network.Local.Equals(contact.TunnelServer)) // use dhtclient compare
{
lookup.RunInCoreAsync(delegate()
{
TcpConnect direct = lookup.Network.TcpControl.GetProxy(packet.Target);
if (direct != null)
{
packet.SourceServer = new DhtAddress(Core.LocalIP, lookup.Network.GetLocalSource());
bytesSent = direct.SendPacket(packet);
}
});
return bytesSent;
}
// if not open send proxied through local lookup proxy
// NAT as well because receiver would need to send all responses through same local lookup proxy
// for NATd host to get replies
if (Core.Firewall != FirewallType.Open)
{
packet.TargetServer = contact.TunnelServer;
lookup.RunInCoreAsync(delegate()
{
TcpConnect server = lookup.Network.TcpControl.GetProxy(packet.TargetServer) ?? // direct path
lookup.Network.TcpControl.GetProxyServer(contact.IP) ?? // reRoute through same server
lookup.Network.TcpControl.GetRandomProxy(); // random proxy
if (server != null)
{
packet.SourceServer = new DhtAddress(server.RemoteIP, server);
bytesSent = server.SendPacket(packet);
}
});
}
// else we are open, send op ip address in the souce server
else
{
packet.SourceServer = new DhtAddress(Core.LocalIP, lookup.Network.GetLocalSource());
lookup.RunInCoreAsync(delegate()
{
bytesSent = lookup.Network.UdpControl.SendTo(contact.TunnelServer, packet);
});
}
return bytesSent;
}
public void ReceiveTunnelPacket(G2ReceivedPacket raw, TunnelPacket tunnel)
{
if (Core.InvokeRequired) // called from lookup core's thread
{
Core.RunInCoreAsync(delegate() { ReceiveTunnelPacket(raw, tunnel); });
return;
}
Debug.Assert(!IsLookup);
if (IsLookup)
return;
// decrypt public packet
if (Core.Sim == null || Core.Sim.Internet.TestEncryption) // turn off encryption during simulation
{
if (tunnel.Payload.Length < 16)
throw new Exception("Not enough data received for IV");
tunnel.Payload = Utilities.DecryptBytes(tunnel.Payload, tunnel.Payload.Length, LocalAugmentedKey);
}
G2ReceivedPacket opPacket = new G2ReceivedPacket();
opPacket.Root = new G2Header(tunnel.Payload);
// set source information
if (G2Protocol.ReadPacket(opPacket.Root))
{
opPacket.Source = new DhtAddress();
// used to add direct op contact if source firewall is open
// or re-routing through same lookup proxy
opPacket.Source.IP = raw.Source.IP;
opPacket.Source.UdpPort = raw.Source.UdpPort;
// op user/client set by net/comm processing
opPacket.Source.TunnelClient = tunnel.Source;
opPacket.Source.TunnelServer = tunnel.SourceServer;
PacketLogEntry logEntry = new PacketLogEntry(Core.TimeNow, TransportProtocol.Tunnel, DirectionType.In, opPacket.Source, opPacket.Root.Data);
LogPacket(logEntry);
IncomingPacket(opPacket);
}
}
// nodes in lookup proxy mode are psuedo-open, instead of udp they send tunneled packets
// tunnel packets include routing information to the lookup target as well as
// the encrytped operation packet embedded in the payload
public int SendTunnelPacket(DhtAddress contact, G2Packet embed)
{
Debug.Assert(contact.TunnelClient != null && contact.TunnelServer != null);
Debug.Assert(Core.Context.Lookup != null);
Debug.Assert(!IsLookup);
Debug.Assert(Core.User.Settings.OpAccess != AccessType.Secret);
if (IsLookup ||
Core.Context.Lookup == null ||
Core.User.Settings.OpAccess == AccessType.Secret)
{
return(0);
}
OpCore lookup = Core.Context.Lookup;
// tunnel packet through lookup network
byte[] encoded = embed.Encode(Protocol);
PacketLogEntry logEntry = new PacketLogEntry(Core.TimeNow, TransportProtocol.Tunnel, DirectionType.Out, contact, encoded);
LogPacket(logEntry);
TunnelPacket packet = new TunnelPacket();
// encrypt, turn off encryption during simulation
if (Core.Sim == null || Core.Sim.Internet.TestEncryption)
{
packet.Payload = Utilities.EncryptBytes(encoded, GetAugmentedKey(contact.UserID));
}
else
{
packet.Payload = encoded;
}
packet.Source = new TunnelAddress(lookup.Network.Local, Core.TunnelID);
packet.Target = contact.TunnelClient;
int bytesSent = 0;
// if we are the tunnel server (our lookup net is open, but op is blocked)
if (lookup.Network.Local.Equals(contact.TunnelServer)) // use dhtclient compare
{
lookup.RunInCoreAsync(delegate()
{
TcpConnect direct = lookup.Network.TcpControl.GetProxy(packet.Target);
if (direct != null)
{
packet.SourceServer = new DhtAddress(Core.LocalIP, lookup.Network.GetLocalSource());
bytesSent = direct.SendPacket(packet);
}
});
return(bytesSent);
}
// if not open send proxied through local lookup proxy
// NAT as well because receiver would need to send all responses through same local lookup proxy
// for NATd host to get replies
if (Core.Firewall != FirewallType.Open)
{
packet.TargetServer = contact.TunnelServer;
lookup.RunInCoreAsync(delegate()
{
TcpConnect server = lookup.Network.TcpControl.GetProxy(packet.TargetServer) ?? // direct path
lookup.Network.TcpControl.GetProxyServer(contact.IP) ?? // reRoute through same server
lookup.Network.TcpControl.GetRandomProxy(); // random proxy
if (server != null)
{
packet.SourceServer = new DhtAddress(server.RemoteIP, server);
bytesSent = server.SendPacket(packet);
}
});
}
// else we are open, send op ip address in the souce server
else
{
packet.SourceServer = new DhtAddress(Core.LocalIP, lookup.Network.GetLocalSource());
lookup.RunInCoreAsync(delegate()
{
bytesSent = lookup.Network.UdpControl.SendTo(contact.TunnelServer, packet);
});
}
return(bytesSent);
}
public void ReceivePacket(G2ReceivedPacket packet)
{
// Network packet
if (packet.Root.Name == RootPacket.Network)
{
NetworkPacket netPacket = NetworkPacket.Decode(packet.Root);
G2ReceivedPacket embedded = new G2ReceivedPacket();
embedded.Tcp = packet.Tcp;
embedded.Source = packet.Source;
embedded.Source.UserID = netPacket.SourceID;
embedded.Source.ClientID = netPacket.ClientID;
embedded.Root = new G2Header(netPacket.InternalData);
// from - received from proxy server
if (netPacket.FromAddress != null)
{
if (packet.ReceivedUdp)
{
throw new Exception("From tag set on packet received udp");
}
if (packet.Tcp.Proxy != ProxyType.Server)
{
throw new Exception("From tag (" + netPacket.FromAddress.ToString() + ") set on packet not received from server (" + packet.Tcp.ToString() + ")");
}
embedded.Source = new DhtContact(netPacket.FromAddress);
}
// to - received from proxied node, and not for us
if (netPacket.ToAddress != null &&
!(netPacket.ToAddress.UserID == Local.UserID && netPacket.ToAddress.ClientID == Local.ClientID))
{
if (packet.ReceivedUdp)
{
throw new Exception("To tag set on packet received udp");
}
if (packet.Tcp.Proxy == ProxyType.Server || packet.Tcp.Proxy == ProxyType.Unset)
{
throw new Exception("To tag set on packet received from server");
}
DhtAddress address = netPacket.ToAddress;
netPacket.ToAddress = null;
TcpConnect direct = TcpControl.GetProxy(address);
if (direct != null)
{
direct.SendPacket(netPacket);
}
else
{
UdpControl.SendTo(address, netPacket);
}
return;
}
// process
if (G2Protocol.ReadPacket(embedded.Root))
{
ReceiveNetworkPacket(embedded);
}
}
// Tunnel Packet
else if (packet.Root.Name == RootPacket.Tunnel)
{
// can only tunnel over lookup network
if (!IsLookup)
{
return;
}
PacketLogEntry logEntry = new PacketLogEntry(Core.TimeNow, TransportProtocol.Tunnel, DirectionType.In, packet.Source, packet.Root.Data);
LogPacket(logEntry);
TunnelPacket tunnel = TunnelPacket.Decode(packet.Root);
// handle locally
if (tunnel.Target.Equals(Local))
{
Core.Context.Cores.LockReading(delegate()
{
foreach (OpCore core in Core.Context.Cores)
{
if (core.TunnelID == tunnel.Target.TunnelID)
{
core.Network.ReceiveTunnelPacket(packet, tunnel);
}
}
});
}
else if (tunnel.TargetServer != null)
{
TcpConnect direct = TcpControl.GetProxy(tunnel.Target);
// if directly connected add from and forwared
if (direct != null)
{
direct.SendPacket(tunnel);
}
// only forward udp if received over tcp from a proxied host
else if (tunnel.TargetServer != null && packet.ReceivedTcp && packet.Tcp.Proxy != ProxyType.Server)
{
UdpControl.SendTo(tunnel.TargetServer, tunnel);
}
}
}
// Communication Packet
else if (packet.Root.Name == RootPacket.Comm)
{
RudpPacket commPacket = RudpPacket.Decode(packet);
// received direct
packet.Source.UserID = commPacket.SenderID;
packet.Source.ClientID = commPacket.SenderClient;
// remote node is proxied
if (commPacket.RemoteProxy != null)
{
packet.Source = new DhtContact(commPacket.RemoteProxy);
}
// For local host
if (commPacket.TargetID == Local.UserID && commPacket.TargetClient == Local.ClientID)
{
ReceiveCommPacket(packet, commPacket);
return;
}
// Also Forward to appropriate node
TcpConnect socket = TcpControl.GetProxy(commPacket.TargetID, commPacket.TargetClient);
if (socket != null)
{
// forward to proxied node - strip TO flag, add from address
commPacket.ToAddress = null;
commPacket.RemoteProxy = packet.Source; // if remote proxy is null, then we are setting this to the packet's original source
socket.SendPacket(commPacket);
return;
}
// received from a proxied node, forward udp
if (packet.ReceivedTcp && commPacket.ToAddress != null)
{
DhtAddress target = commPacket.ToAddress;
commPacket.ToAddress = null; // strip TO flag
commPacket.RemoteProxy = new DhtAddress(Core.LocalIP, GetLocalSource());
UdpControl.SendTo(target, commPacket);
}
}
}
