feat: Upgrade server with HyNB v2.4 modular architecture, minigames, admin GM web panel, companion summons, and car radio

Ananta.SDK/Network/TcpSession.cs

@@ -8,9 +8,20 @@ namespace Ananta.SDK.Network;
 public sealed class TcpSession
 {
     private readonly SemaphoreSlim _sendLock = new(1, 1);
+    private readonly CancellationTokenSource _closed = new();
+    /// <summary>会话关闭时触发。逐字对齐捐赠端 <c>TcpSession.ClosedToken</c>（<c>Ananta.SDK/Network/TcpSession.cs:13</c>）。
+    /// ⛑ 主线原本已有 <c>_closed</c> 且 <c>Close()</c> 会 Cancel，只是没公开 → 这里<b>只加属性，不改生命周期</b>。</summary>
+    public CancellationToken ClosedToken => _closed.Token;
+    private Task? _heartbeat;
+    private int _isClosed;
     private UxChaCha8? _readCryptor;
     private UxChaCha8? _writeCryptor;
 
+    /// <summary>服务端 → 客户端传输层 keepalive 间隔（毫秒）。<b>0 = 关闭</b>（沿用旧行为）。</summary>
+    public int HeartbeatMs { get; }
+    /// <summary>单次加密写的上限（毫秒）；超时会退役这条连接。<b>0 = 不设上限</b>（沿用旧行为）。</summary>
+    public int WriteTimeoutMs { get; }
+
     public string Id { get; } = Guid.NewGuid().ToString("N")[..6];
     public TcpClient Client { get; }
     public NetworkStream Stream { get; }
@@ -18,11 +29,15 @@ public sealed class TcpSession
     public Dictionary<string, object> Items { get; } = new();
     public bool CryptReady => _readCryptor is not null && _writeCryptor is not null;
 
-    public TcpSession(TcpClient client, string scope)
+    public TcpSession(TcpClient client, string scope, int heartbeatMs = 0, int writeTimeoutMs = 15000)
     {
         Client = client;
         Stream = client.GetStream();
         Log = new ServerLogger($"{scope}:{Id}");
+        HeartbeatMs = heartbeatMs;
+        WriteTimeoutMs = writeTimeoutMs;
+        // Small real-time RPCs should not wait for Nagle/delayed-ACK batching.
+        Client.NoDelay = true;
     }
 
     public Task<Frame?> ReadFrameAsync(CancellationToken token)
@@ -69,23 +84,36 @@ public sealed class TcpSession
         // UXRSA.Verify result branch is patched out to accept the local
         // unsigned handshake.
 
-        await _sendLock.WaitAsync(token);
-        try
-        {
-            // The handshake reply itself is plaintext. Encryption becomes active
-            // only for the next frame in each direction.
-            await FrameCodec.WriteFrameAsync(Stream, 0x01, payload, cryptor: null, token: token);
-            _readCryptor = new UxChaCha8(clientWriteKey, streamNonce);
-            _writeCryptor = new UxChaCha8(clientReadKey, streamNonce);
-        }
-        finally
-        {
-            _sendLock.Release();
-        }
+        // The handshake reply itself is plaintext. Encryption becomes active
+        // only for the next frame in each direction — which is why the keys are
+        // published *after* this write instead of before it.
+        await WriteRawAsync(0x01, payload, token);
+        _readCryptor = new UxChaCha8(clientWriteKey, streamNonce);
+        _writeCryptor = new UxChaCha8(clientReadKey, streamNonce);
 
         Log.Info($"HS keys clientWrite={Convert.ToHexString(clientWriteKey)} clientRead={Convert.ToHexString(clientReadKey)} nonce={Convert.ToHexString(streamNonce)} aes={Convert.ToHexString(aesKey)}");
 
         Log.Info("HS ok -> UXChaCha8 enabled");
+
+        if (HeartbeatMs > 0) _heartbeat ??= SendHeartbeatsAsync();
+    }
+
+    private async Task SendHeartbeatsAsync()
+    {
+        // Keep an inbound liveness signal on every socket, including idle gates,
+        // independently of the client's RPC and heartbeat scheduling.
+        using var timer = new PeriodicTimer(TimeSpan.FromMilliseconds(HeartbeatMs));
+        try
+        {
+            while (await timer.WaitForNextTickAsync(_closed.Token))
+                await SendFrameAsync(0x03, BitConverter.GetBytes(Environment.TickCount64), _closed.Token);
+        }
+        catch (OperationCanceledException) when (_closed.IsCancellationRequested) { }
+        catch (Exception ex)
+        {
+            Log.Warn($"heartbeat send stopped: {ex.Message}");
+            Close();
+        }
     }
 
     public Task SendFrameAsync(byte mode, byte[] body, CancellationToken token)
@@ -104,22 +132,51 @@ public sealed class TcpSession
         return WriteEncryptedFrameAsync(0x09, RpcPacketWriter.WriteReturn(methodId, invokeId, err, body), token);
     }
 
-    private async Task WriteEncryptedFrameAsync(byte mode, ReadOnlyMemory<byte> body, CancellationToken token)
+    private Task WriteRawAsync(byte mode, ReadOnlyMemory<byte> body, CancellationToken token)
+        => WriteFrameAsync(mode, body, null, token);
+
+    private async Task WriteFrameAsync(byte mode, ReadOnlyMemory<byte> body, UxChaCha8? cryptor, CancellationToken token)
     {
-        await _sendLock.WaitAsync(token);
+        using var deadline = WriteTimeoutMs > 0
+            ? CancellationTokenSource.CreateLinkedTokenSource(token, _closed.Token)
+            : null;
+        if (deadline is not null) deadline.CancelAfter(WriteTimeoutMs);
+        var linked = deadline?.Token ?? token;
+        var acquired = false;
         try
         {
-            await FrameCodec.WriteFrameAsync(Stream, mode, body, _writeCryptor, token);
+            await _sendLock.WaitAsync(linked);
+            acquired = true;
+            await FrameCodec.WriteFrameAsync(Stream, mode, body, cryptor, linked);
+        }
+        catch (OperationCanceledException) when (!_closed.IsCancellationRequested && !token.IsCancellationRequested)
+        {
+            // A partially-written encrypted frame cannot be retried: the stream cipher already
+            // advanced. Retire only this socket so everyone else keeps being served.
+            Close();
+            throw new IOException($"TCP send cancelled or exceeded the {(WriteTimeoutMs > 0 ? WriteTimeoutMs : 0)}-ms write deadline");
+        }
+        catch (Exception ex) when (ex is IOException or SocketException)
+        {
+            Close();
+            throw;
         }
         finally
         {
-            _sendLock.Release();
+            if (acquired) _sendLock.Release();
         }
     }
 
+    private Task WriteEncryptedFrameAsync(byte mode, ReadOnlyMemory<byte> body, CancellationToken token)
+        => WriteFrameAsync(mode, body, _writeCryptor, token);
+
     public void Close()
     {
+        if (Interlocked.Exchange(ref _isClosed, 1) != 0) return;
+        _closed.Cancel();
         try { Client.Close(); } catch { }
-        _sendLock.Dispose();
+        // Pending async sends may still own or await this semaphore. Disposing it
+        // here races their finally/Release and hides the actual socket closure.
+        // It owns no wait handle; let it be collected with this session.
     }
 }