public static void ReplyToDataRequest(ClientInstance instance, string message, CommandDataTypes dataType)
{
List <DataReplyFormat> serverMessage = new();
serverMessage.Add(new DataReplyFormat
{
MessageType = MessageTypes.DATAREPLY,
DataType = dataType,
Data = message,
});
string json = Serialization.Serialize(serverMessage, false);
byte[] data = Serialization.AddEndCharToMessage(json);
int index = ServerMessage.FindClientKeysIndex(instance.client);
byte[] encrypted = MessageHandler.EncryptMessage(data, ServerHandler.activeClients[index].RSAModulus, ServerHandler.activeClients[index].RSAExponent);
StreamHandler.WriteToStream(instance.stream, encrypted);
}
// The loop to recieve incoming packets.
public static void RecieveMessage(ClientInstance instance)
{
long lastMessage = 0;
byte[] bytes = new byte[8192];
while ((instance.stream.Read(bytes, 0, bytes.Length)) > 0)
{
// Checks if the client has sent messages too fast.
if (DateTimeOffset.UtcNow.ToUnixTimeMilliseconds() - lastMessage >= ServerConfigFormat.serverChosenClientTime)
{
lastMessage = DateTimeOffset.UtcNow.ToUnixTimeMilliseconds();
// I had some issues with trailing zero bytes, and this solves that.
int i = bytes.Length - 1;
while (bytes[i] == 0)
{
--i;
}
byte[] bytesResized = new byte[i + 1];
Array.Copy(bytes, bytesResized, i + 1);
Array.Clear(bytes, 0, bytes.Length); // Seems to solve an issue where bytes from the last message stick around.
// Is client verified, meaning client has established initial connection and communication.
if (instance.clientVerified)
{
VerifiedRecieve(instance, bytesResized);
}
else
{
NotVerifiedRecieve(instance, bytesResized);
}
}
}
}
public static void VerifiedRecieve(ClientInstance instance, byte[] bytes)
{
// Random CryptographicException that i am not able to replicate
// TODO Investigate reason for exception.
string message = "";
try
{
message = Encryption.DecryptMessageData(bytes);
}
catch (CryptographicException)
{
int index = ServerMessage.FindClientKeysIndex(instance.client);
string serverMessage = String.Format("{0} Was kicked due to a cryptography error.", ServerHandler.activeClients[index].Username);
ServerMessage.ServerGlobalMessage(ConsoleColor.Yellow, serverMessage);
instance.client.Close();
}
string messageFormatted = Common.ReturnEndOfStream(message);
byte[] messageBytes = Encoding.ASCII.GetBytes(messageFormatted);
List <MessageFormat> messageList;
switch (Common.ReturnMessageType(messageBytes))
{
case MessageTypes.MESSAGE:
int index = ServerMessage.FindClientKeysIndex(instance.client);
// Error when deserializing message.
// Could mean corrupt or icorrect data has been transmitted.
try
{
messageList = Serialization.DeserializeMessageFormat(messageFormatted);
List <MessageReplyFormat> replyFormat = new();
replyFormat.Add(new MessageReplyFormat
{
MessageType = MessageTypes.MESSAGEREPLY,
Message = messageList[0].Message,
ID = ServerHandler.activeClients[index].ID,
Username = ServerHandler.activeClients[index].Username,
UsernameColor = ServerHandler.activeClients[index].UsernameColor,
});
ConsoleOutput.RecievedMessageReplyFormat(replyFormat, ServerHandler.activeClients[index].ChannelID);
// Encrypts the message and sends it to all clients.
RepeatToAllClientsInChannel(replyFormat, instance);
}
catch (JsonException)
{
string serverMessage = String.Format("({0}) {1} Was kicked due to an invalid message.", ServerHandler.activeClients[index].ID, ServerHandler.activeClients[index].Username);
ServerMessage.ServerGlobalMessage(ConsoleColor.Yellow, serverMessage);
instance.client.Close();
}
break;
case MessageTypes.DATAREQUEST:
List <DataRequestFormat> dataList = Serialization.DeserializeDataRequestFormat(messageFormatted);
CommandHandler.RecievedDataRequest(instance, dataList);
break;
}
}
public static void ClientChannelSwitch(ClientInstance instance, string parameters)
{
ChannelHandler.ClientRequestsChannelSwitch(instance, parameters);
}