/// <summary>
/// This sends a network message with a message ID on the connection. This message is sent on channel zero, which by default is the reliable channel.
/// </summary>
/// <typeparam name="T">The message type to unregister.</typeparam>
/// <param name="msg">The message to send.</param>
/// <param name="channelId">The transport layer channel to send on.</param>
/// <returns></returns>
public virtual bool Send <T>(T msg, int channelId = Channels.DefaultReliable) where T : IMessageBase
{
// pack message and send
byte[] message = MessagePacker.Pack(msg);
NetworkDiagnostics.OnSend(msg, channelId, message.Length, 1);
return(SendBytes(message, channelId));
}
private static NetworkMessageDelegate MessageHandler <T>(Action <INetworkConnection, T> handler)
where T : IMessageBase, new()
{
void AdapterFunction(INetworkConnection conn, NetworkReader reader, int channelId)
{
// protect against DOS attacks if attackers try to send invalid
// data packets to crash the server/client. there are a thousand
// ways to cause an exception in data handling:
// - invalid headers
// - invalid message ids
// - invalid data causing exceptions
// - negative ReadBytesAndSize prefixes
// - invalid utf8 strings
// - etc.
//
// let's catch them all and then disconnect that connection to avoid
// further attacks.
T message = default(T) != null ? default : new T();
try
{
message.Deserialize(reader);
}
finally
{
NetworkDiagnostics.OnReceive(message, channelId, reader.Length);
}
handler(conn, message);
}
return(AdapterFunction);
}
public static void Send <T>(IEnumerable <INetworkConnection> connections, T msg, int channelId = Channels.DefaultReliable) where T : IMessageBase
{
using (PooledNetworkWriter writer = NetworkWriterPool.GetWriter())
{
// pack message into byte[] once
MessagePacker.Pack(msg, writer);
var segment = writer.ToArraySegment();
int count = 0;
foreach (INetworkConnection conn in connections)
{
if (conn is NetworkConnection networkConnection)
{
// send to all connections, but don't wait for them
_ = networkConnection.SendAsync(segment, channelId);
}
else
{
_ = conn.SendAsync(msg, channelId);
}
count++;
}
NetworkDiagnostics.OnSend(msg, channelId, segment.Count, count);
}
}
/// <summary>
/// Sends a message, but notify when it is delivered or lost
/// </summary>
/// <typeparam name="T">type of message to send</typeparam>
/// <param name="msg">message to send</param>
/// <param name="token">a arbitrary object that the sender will receive with their notification</param>
public void SendNotify <T>(T msg, object token, byte channelId = (byte)Channels.Unreliable)
{
if (sendWindow.Count == WINDOW_SIZE)
{
NotifyLost?.Invoke(this, token);
return;
}
using (PooledNetworkWriter writer = NetworkWriterPool.GetWriter())
{
var notifyPacket = new NotifyPacket
{
Sequence = (ushort)sequencer.Next(),
ReceiveSequence = receiveSequence,
AckMask = receiveMask
};
sendWindow.Enqueue(new PacketEnvelope
{
Sequence = notifyPacket.Sequence,
Token = token
});
MessagePacker.Pack(notifyPacket, writer);
MessagePacker.Pack(msg, writer);
NetworkDiagnostics.OnSend(msg, channelId, writer.Length, 1);
SendAsync(writer.ToArraySegment(), channelId).Forget();
}
}
internal static NetworkMessageDelegate MessageHandler <T>(Action <NetworkConnection, T> handler) where T : IMessageBase, new() => networkMessage =>
{
// protect against DOS attacks if attackers try to send invalid
// data packets to crash the server/client. there are a thousand
// ways to cause an exception in data handling:
// - invalid headers
// - invalid message ids
// - invalid data causing exceptions
// - negative ReadBytesAndSize prefixes
// - invalid utf8 strings
// - etc.
//
// let's catch them all and then disconnect that connection to avoid
// further attacks.
T message = default;
try
{
message = networkMessage.ReadMessage <T>();
}
catch (Exception exception)
{
Debug.LogError("Closed connection: " + networkMessage.conn.connectionId + ". This can happen if the other side accidentally (or an attacker intentionally) sent invalid data. Reason: " + exception);
networkMessage.conn.Disconnect();
return;
}
finally
{
// TODO: Figure out the correct channel
NetworkDiagnostics.OnReceive(message, -1, networkMessage.reader.Length);
}
handler(networkMessage.conn, message);
};
internal static NetworkMessageDelegate WrapHandler <T, C>(Action <C, T> handler, bool requireAuthentication)
where T : struct, NetworkMessage
where C : NetworkConnection
=> (conn, reader, channelId) =>
{
// protect against DOS attacks if attackers try to send invalid
// data packets to crash the server/client. there are a thousand
// ways to cause an exception in data handling:
// - invalid headers
// - invalid message ids
// - invalid data causing exceptions
// - negative ReadBytesAndSize prefixes
// - invalid utf8 strings
// - etc.
//
// let's catch them all and then disconnect that connection to avoid
// further attacks.
T message = default;
try
{
if (requireAuthentication && !conn.isAuthenticated)
{
// message requires authentication, but the connection was not authenticated
Debug.LogWarning($"Closing connection: {conn}. Received message {typeof(T)} that required authentication, but the user has not authenticated yet");
conn.Disconnect();
return;
}
//Debug.Log($"ConnectionRecv {conn} msgType:{typeof(T)} content:{BitConverter.ToString(reader.buffer.Array, reader.buffer.Offset, reader.buffer.Count)}");
// if it is a value type, just use default(T)
// otherwise allocate a new instance
message = reader.Read <T>();
}
catch (Exception exception)
{
Debug.LogError($"Closed connection: {conn}. This can happen if the other side accidentally (or an attacker intentionally) sent invalid data. Reason: {exception}");
conn.Disconnect();
return;
}
finally
{
// TODO: Figure out the correct channel
NetworkDiagnostics.OnReceive(message, channelId, reader.Length);
}
// user handler exception should not stop the whole server
try
{
// user implemented handler
handler((C)conn, message);
}
catch (Exception e)
{
Debug.LogError($"Exception in MessageHandler: {e.GetType().Name} {e.Message}\n{e.StackTrace}");
conn.Disconnect();
}
};
/// <summary>
/// This sends a network message with a message ID on the connection. This message is sent on channel zero, which by default is the reliable channel.
/// </summary>
/// <typeparam name="T">The message type to unregister.</typeparam>
/// <param name="msg">The message to send.</param>
/// <param name="channelId">The transport layer channel to send on.</param>
/// <returns></returns>
public bool Send <T>(T msg, int channelId = Channels.DefaultReliable) where T : IMessageBase
{
using (PooledNetworkWriter writer = NetworkWriterPool.GetWriter())
{
// pack message and send allocation free
MessagePacker.Pack(msg, writer);
NetworkDiagnostics.OnSend(msg, channelId, writer.Position, 1);
return(Send(writer.ToArraySegment(), channelId));
}
}
/// <summary>
/// This sends a network message to the connection. You can await it to check for errors
/// </summary>
/// <typeparam name="T">The message type</typeparam>
/// <param name="msg">The message to send.</param>
/// <param name="channelId">The transport layer channel to send on.</param>
/// <returns></returns>
public virtual UniTask SendAsync <T>(T msg, byte channelId = (byte)Channels.Reliable)
{
using (PooledNetworkWriter writer = NetworkWriterPool.GetWriter())
{
// pack message and send allocation free
MessagePacker.Pack(msg, writer);
NetworkDiagnostics.OnSend(msg, channelId, writer.Length, 1);
return(SendAsync(writer.ToArraySegment(), channelId));
}
}
/// <summary>Send a NetworkMessage to this connection over the given channel.</summary>
public void Send <T>(T msg, int channelId = Channels.Reliable)
where T : struct, NetworkMessage
{
using (PooledNetworkWriter writer = NetworkWriterPool.GetWriter())
{
// pack message and send allocation free
MessagePacking.Pack(msg, writer);
NetworkDiagnostics.OnSend(msg, channelId, writer.Position, 1);
Send(writer.ToArraySegment(), channelId);
}
}
/// <summary>
/// This sends a network message with a message ID on the connection. This message is sent on channel zero, which by default is the reliable channel.
/// </summary>
/// <typeparam name="T">The message type to unregister.</typeparam>
/// <param name="msg">The message to send.</param>
/// <param name="channelId">The transport layer channel to send on.</param>
/// <returns></returns>
public virtual bool Send <T>(T msg, int channelId = Channels.DefaultReliable) where T : IMessageBase
{
NetworkWriter writer = NetworkWriterPool.GetWriter();
// pack message and send allocation free
MessagePacker.Pack(msg, writer);
NetworkDiagnostics.OnSend(msg, channelId, writer.Position, 1);
bool result = Send(writer.ToArraySegment(), channelId);
NetworkWriterPool.Recycle(writer);
return(result);
}
internal static NetworkMessageDelegate MessageHandler <T, C>(Action <C, T> handler, bool requireAuthenication)
where T : IMessageBase, new()
where C : NetworkConnection
=> (conn, reader, channelId) =>
{
// protect against DOS attacks if attackers try to send invalid
// data packets to crash the server/client. there are a thousand
// ways to cause an exception in data handling:
// - invalid headers
// - invalid message ids
// - invalid data causing exceptions
// - negative ReadBytesAndSize prefixes
// - invalid utf8 strings
// - etc.
//
// let's catch them all and then disconnect that connection to avoid
// further attacks.
T message = default;
try
{
if (requireAuthenication && !conn.isAuthenticated)
{
// message requires authentication, but the connection was not authenticated
Debug.LogWarning($"Closing connection: {conn}. Received message {typeof(T)} that required authentication, but the user has not authenticated yet");
conn.Disconnect();
return;
}
// if it is a value type, just use defult(T)
// otherwise allocate a new instance
message = default(T) != null ? default(T) : new T();
message.Deserialize(reader);
}
catch (Exception exception)
{
Debug.LogError("Closed connection: " + conn + ". This can happen if the other side accidentally (or an attacker intentionally) sent invalid data. Reason: " + exception);
conn.Disconnect();
return;
}
finally
{
// TODO: Figure out the correct channel
NetworkDiagnostics.OnReceive(message, channelId, reader.Length);
}
handler((C)conn, message);
};
private static NetworkMessageDelegate MessageHandler <T, C>(Action <C, T> handler, bool requireAuthenication)
where T : IMessageBase, new()
where C : NetworkConnection
{
void AdapterFunction(NetworkConnection conn, NetworkReader reader, int channelId)
{
// protect against DOS attacks if attackers try to send invalid
// data packets to crash the server/client. there are a thousand
// ways to cause an exception in data handling:
// - invalid headers
// - invalid message ids
// - invalid data causing exceptions
// - negative ReadBytesAndSize prefixes
// - invalid utf8 strings
// - etc.
//
// let's catch them all and then disconnect that connection to avoid
// further attacks.
T message = default;
try
{
if (requireAuthenication && !conn.isAuthenticated)
{
// message requires authentication, but the connection was not authenticated
Debug.LogWarning($"Closing connection: {conn}. Received message {typeof(T)} that required authentication, but the user has not authenticated yet");
conn.Disconnect();
return;
}
message = default(T) != null ? default(T) : new T();
message.Deserialize(reader);
}
finally
{
NetworkDiagnostics.OnReceive(message, channelId, reader.Length);
}
handler((C)conn, message);
}
return(AdapterFunction);
}
public static void Send <T>(IEnumerable <INetworkConnection> connections, T msg, byte channelId = (byte)Channels.Reliable)
{
using (PooledNetworkWriter writer = NetworkWriterPool.GetWriter())
{
// pack message into byte[] once
MessagePacker.Pack(msg, writer);
var segment = writer.ToArraySegment();
int count = 0;
foreach (INetworkConnection conn in connections)
{
// send to all connections, but don't wait for them
conn.SendAsync(segment, channelId).Forget();
count++;
}
NetworkDiagnostics.OnSend(msg, channelId, segment.Count, count);
}
}