public static void DecryptPacket(ServerState state, byte[] packet)
{
using (var reader = new Reader(packet))
{
var ID = reader.ReadUInt16();
reader.Seek(3, SeekOrigin.Current);
var Version = reader.ReadUInt16();
byte[] cipherText = reader.ReadAllBytes, plainText;
var Name = Packet_Names.GetName(ID);
switch (ID)
{
case 10100:
{
plainText = cipherText;
break;
}
case 10101:
{
state.ClientKey = cipherText.Take(32).ToArray();
var nonce = GenericHash.Hash(state.ClientKey.Concat(state.ServerKey.PublicKey).ToArray(), null,
24);
cipherText = cipherText.Skip(32).ToArray();
plainText = PublicKeyBox.Open(cipherText, nonce, state.ServerKey.PrivateKey, state.ClientKey);
state.SessionKey = plainText.Take(24).ToArray();
state.ClientState.Nonce = plainText.Skip(24).Take(24).ToArray();
plainText = plainText.Skip(24).Skip(24).ToArray();
break;
}
default:
{
state.ClientState.Nonce = Utilities.Increment(Utilities.Increment(state.ClientState.Nonce));
plainText = SecretBox.Open(new byte[16].Concat(cipherText).ToArray(), state.ClientState.Nonce,
state.SharedKey);
break;
}
}
ClientCrypto.EncryptPacket(state.ClientState, ID, Version, plainText);
Console.WriteLine(
$"[{DateTime.Now.ToLongTimeString()}, CLIENT, {ID}] {Resources.Definition.Decode(new Reader(plainText), ID)}");
Logger.Write(BitConverter.ToString(plainText).Replace("-", string.Empty), $"{ID}_{Name}",
LogType.PACKET);
}
}
public string Decode(Reader reader, ushort ID)
{
if (this.ContainsKey(ID))
{
try
{
Type _Type = Activator.CreateInstance(this[ID], reader, ID) as Type;
_Type.Decode();
return(_Type.Json.Count == 0 ? string.Empty : JsonConvert.SerializeObject(_Type.Json, Formatting.Indented));
}
catch (Exception)
{
return($"Failed to decode {ID}.");
}
}
else
{
return($"Missing definition for Packet {ID} [{Packet_Names.GetName(ID)}]");
}
}