public static void Initialize()
{
if (IsOpen || ListeningThread != null)
{
return;
}
MasterServerList.Clear();
Prospects = new Dictionary <string, Client>();
Clients = new Dictionary <string, Client>();
ushort port = (ushort)Configuration.General["Master Port"];
Sock = new UdpClient(new IPEndPoint(IPAddress.Any, port));
// TODO figure out what this has to do with ICMP (in client too)
/*uint IOC_IN = 0x80000000,
* IOC_VENDOR = 0x18000000,
* SIO_UDP_CONNRESET = IOC_IN | IOC_VENDOR | 12;
* Sock.Client.IOControl((int)SIO_UDP_CONNRESET, new byte[] {0}, null);*/
IsOpen = true;
ListeningThread = new Thread(Listener);
ListeningThread.Start();
}
protected override void OnReceive(byte[] data)
{
Packet packet =
Encryptor == null?Packet.FromBytes(data)
: Packet.FromBytes(Encryptor.Parse(data));
if (packet == null)
{
Disconnect(Frame.kClosingReason.ProtocolError, "Packet received was not legal.");
return;
}
if (packet.Id != (int)kInterMasterId.KeyExchange && Encryptor == null)
{
Disconnect(Frame.kClosingReason.ProtocolError, "You must exchange keys before performing any other operations.");
return;
}
// TODO rate limiting by ip
switch ((kInterMasterId)packet.Id)
{
case kInterMasterId.KeyExchange:
Key.ParseResponsePacket(packet);
if (!Key.Succeeded)
{
Disconnect(Frame.kClosingReason.ProtocolError, "Could not exchange keys.");
return;
}
Encryptor = new StreamCipher(Key.PrivateKey);
break;
case kInterMasterId.LoginAttempt:
if (packet.RegionCount != 3 || !packet.CheckRegionsMaxLength(0, 16, 255) || !packet.CheckRegionLengths(2, 2))
{
break;
}
Session session;
using (var db = new ScapeDb()) {
User user;
if ((user = db.Users.FirstOrDefault(x => x.Username == packet[0])) == null)
{
SendEncrypted(new Packet(kInterMasterId.LoginAttempt, Convert.ToByte(false), "User does not exist."));
break;
}
if (packet[1].Str.Trim() == "" || !packet[1].Str.CheckPassword(user.Password))
{
SendEncrypted(new Packet(kInterMasterId.LoginAttempt, Convert.ToByte(false), "Password is incorrect."));
break;
}
if (user.Session?.DeltaLastPing.TotalMinutes < 3)
{
SendEncrypted(new Packet(kInterMasterId.LoginAttempt, Convert.ToByte(false), "You are already logged in. Log out or try again shortly."));
break;
}
ushort serverId = packet[2].Raw.UnpackUInt16();
if (!MasterServerList.HasId(serverId))
{
SendEncrypted(new Packet(kInterMasterId.LoginAttempt, Convert.ToByte(false), "The world you have specified is offline."));
break;
}
if (user.Session?.DeltaLastPing.TotalMinutes >= 3)
{
db.Entry(user.Session).State = EntityState.Deleted;
db.SaveChanges();
}
db.Sessions.Add(session = new Session {
Id = user.Id,
Secret = RNG.NextBytes(16),
ServerId = serverId,
LastPing = DateTime.UtcNow
});
db.SaveChanges();
}
var server = MasterServerList.Get((ushort)session.ServerId);
SendEncrypted(new Packet(kInterMasterId.LoginAttempt, Convert.ToByte(true), session.Secret, server.Address.ToString(), server.Port.Pack()));
break;
case kInterMasterId.RegistrationAttempt:
if (packet.RegionCount != 3 || !packet.CheckAllMaxLength(0xFF))
{
break;
}
if (!packet[0].Raw.IsAsciiString())
{
SendEncrypted(new Packet(kInterMasterId.RegistrationAttempt, Convert.ToByte(false), "Your username cannot contain unicode characters."));
break;
}
string username = packet[0].Str.Trim(),
password = packet[1].Str.Trim(),
email = packet[2].Str.Trim();
if (username.Length > 16 || !UsernameRegex.IsMatch(username))
{
SendEncrypted(new Packet(kInterMasterId.RegistrationAttempt, Convert.ToByte(false), "The username is max 16 characters and can only be letters, numbers, and underscores."));
break;
}
if (!EmailRegex.IsMatch(email))
{
SendEncrypted(new Packet(kInterMasterId.RegistrationAttempt, Convert.ToByte(false), "The email address is malformed."));
break;
}
using (var db = new ScapeDb()) {
if (db.Users.FirstOrDefault(x => x.Username == username) != null)
{
SendEncrypted(new Packet(kInterMasterId.RegistrationAttempt, Convert.ToByte(false), "This username is already in use."));
break;
}
if (db.Users.FirstOrDefault(x => x.Email == email) != null)
{
SendEncrypted(new Packet(kInterMasterId.RegistrationAttempt, Convert.ToByte(false), "This email address is already in use."));
break;
}
// TODO email activation
db.Users.Add(new User {
Username = username,
Password = password.HashPassword(),
Email = email,
Joined = DateTime.UtcNow
});
db.SaveChanges();
}
SendEncrypted(new Packet(kInterMasterId.RegistrationAttempt, Convert.ToByte(true), "Registration was successful."));
break;
case kInterMasterId.ServerListing:
SendEncrypted(MasterServerList.ReportPacket);
break;
default:
Disconnect(Frame.kClosingReason.ProtocolError, "Packet ID could not be understood at this time.");
break;
}
Console.WriteLine($"{Id} says {data.GetString()}");
}
public static void Listener()
{
while (IsOpen)
{
IPEndPoint endPoint = new IPEndPoint(IPAddress.Any, 0);
while (Sock.Available > 0)
{
var data = Sock.Receive(ref endPoint);
var client = endPoint.ToString();
var encryptor = IsClientConnected(client) ? Clients[client].Encryptor : null;
if (data.Take(Packet.MagicNumber.Length).SequenceEqual(Packet.MagicNumber))
{
encryptor = null;
}
Packet packet =
encryptor == null?Packet.FromBytes(data)
: Packet.FromBytes(encryptor.Decrypt(data));
if (packet == null)
{
if (encryptor != null)
{
EncryptionError(endPoint);
}
continue;
}
if (IsProspectConnected(client) && encryptor == null)
{
Prospects[client].LastReceive = DateTime.UtcNow;
}
else if (IsClientConnected(client) && encryptor != null)
{
Clients[client].LastReceive = DateTime.UtcNow;
}
switch ((kIntraSlaveId)packet.Id)
{
case kIntraSlaveId.InitiationAttempt:
if (packet.RegionCount != 1 || IsProspectConnected(client))
{
break;
}
if (packet[0] == Configuration.General["Master Secret"])
{
var key = new Key();
Prospects[client] = new Client {
LastReceive = DateTime.UtcNow,
Address = endPoint,
Key = key
};
Send(key.GenerateRequestPacket(), endPoint);
}
break;
case kIntraSlaveId.KeyExchange:
if (!IsProspectConnected(client))
{
break;
}
var privateKey = Prospects[client].Key.ParseResponsePacket(packet);
if (privateKey != -1)
{
Prospects[client].LastReceive = DateTime.UtcNow;
Prospects[client].Encryptor = new BlockCipher(privateKey);
Clients[client] = Prospects[client];
Prospects.Remove(client);
}
else
{
Prospects.Remove(client);
}
break;
case kIntraSlaveId.StatusUpdate:
if (!IsClientConnected(client) || packet.RegionCount < 1)
{
break;
}
if (!packet.CheckRegionLengths(0, 1))
{
NegativeAck(endPoint, encryptor, kIntraSlaveId.StatusUpdate, "Server count is malformed.");
break;
}
byte serverCount = packet[0].Raw[0];
if (packet.RegionCount != 1 + 3 * serverCount)
{
NegativeAck(endPoint, encryptor, kIntraSlaveId.StatusUpdate, "Region count does not match server count");
break;
}
for (byte i = 0; i < serverCount; ++i)
{
if (!packet.CheckRegionLengths(1 + 3 * i, 2, 2, 2))
{
continue;
}
MasterServerList.Write(new Server {
Id = packet[1 + 3 * i].Raw.UnpackUInt16(),
UserCount = packet[2 + 3 * i].Raw.UnpackUInt16(),
Address = endPoint.Address,
Port = packet[3 + 3 * i].Raw.UnpackUInt16(),
Owner = Clients[client]
});
}
PositiveAck(endPoint, encryptor, kIntraSlaveId.StatusUpdate);
break;
}
}
Prospects = Prospects.Where(x => x.Value.ReceiveDelta.TotalSeconds < 10)
.ToDictionary(x => x.Key, x => x.Value);
var expiredClients = Clients.Where(x => x.Value.ReceiveDelta.TotalSeconds > 60).Select(x => x.Value).ToList();
if (expiredClients.Count > 0)
{
MasterServerList.RemoveServersByOwners(expiredClients);
}
Thread.Sleep(1);
}
}
