pikvm/pikvm#1334: Bad link mode for keyboard events

kvmd/apps/kvmd/api/hid.py

@@ -149,16 +149,17 @@ class HidApi:
     async def __ws_bin_key_handler(self, _: WsSession, data: bytes) -> None:
         try:
             key = valid_hid_key(data[1:].decode("ascii"))
-            state = valid_bool(data[0])
+            state = bool(data[0] & 0b01)
+            finish = bool(data[0] & 0b10)
         except Exception:
             return
-        self.__hid.send_key_event(key, state)
+        self.__hid.send_key_event(key, state, finish)
 
     @exposed_ws(2)
     async def __ws_bin_mouse_button_handler(self, _: WsSession, data: bytes) -> None:
         try:
             button = valid_hid_mouse_button(data[1:].decode("ascii"))
-            state = valid_bool(data[0])
+            state = bool(data[0] & 0b01)
         except Exception:
             return
         self.__hid.send_mouse_button_event(button, state)
@@ -183,7 +184,7 @@ class HidApi:
 
     def __process_ws_bin_delta_request(self, data: bytes, handler: Callable[[Iterable[tuple[int, int]], bool], None]) -> None:
         try:
-            squash = valid_bool(data[0])
+            squash = bool(data[0] & 0b01)
             data = data[1:]
             deltas: list[tuple[int, int]] = []
             for index in range(0, len(data), 2):
@@ -200,9 +201,10 @@ class HidApi:
         try:
             key = valid_hid_key(event["key"])
             state = valid_bool(event["state"])
+            finish = valid_bool(event.get("finish", False))
         except Exception:
             return
-        self.__hid.send_key_event(key, state)
+        self.__hid.send_key_event(key, state, finish)
 
     @exposed_ws("mouse_button")
     async def __ws_mouse_button_handler(self, _: WsSession, event: dict) -> None:
@@ -249,9 +251,10 @@ class HidApi:
         key = valid_hid_key(req.query.get("key"))
         if "state" in req.query:
             state = valid_bool(req.query["state"])
-            self.__hid.send_key_event(key, state)
+            finish = valid_bool(req.query.get("finish", False))
+            self.__hid.send_key_event(key, state, finish)
         else:
-            await self.__hid.send_key_events([(key, True), (key, False)], slow=True)
+            self.__hid.send_key_event(key, True, True)
         return make_json_response()
 
     @exposed_http("POST", "/hid/events/send_mouse_button")

kvmd/clients/kvmd.py

@@ -183,10 +183,12 @@ class KvmdClientWs:
                 self.__communicated = False
 
     async def send_key_event(self, key: str, state: bool) -> None:
-        await self.__writer_queue.put(bytes([1, state]) + key.encode("ascii"))
+        mask = (0b01 if state else 0)
+        await self.__writer_queue.put(bytes([1, mask]) + key.encode("ascii"))
 
     async def send_mouse_button_event(self, button: str, state: bool) -> None:
-        await self.__writer_queue.put(bytes([2, state]) + button.encode("ascii"))
+        mask = (0b01 if state else 0)
+        await self.__writer_queue.put(bytes([2, mask]) + button.encode("ascii"))
 
     async def send_mouse_move_event(self, to_x: int, to_y: int) -> None:
         await self.__writer_queue.put(struct.pack(">bhh", 3, to_x, to_y))

kvmd/keyboard/mappings.py

@@ -170,6 +170,8 @@ class WebModifiers:
     CTRL_RIGHT = "ControlRight"
     CTRLS = set([CTRL_RIGHT, CTRL_RIGHT])
 
+    ALL = (SHIFTS | ALTS | CTRLS)
+
 
 class X11Modifiers:
     SHIFT_LEFT = 65505

kvmd/plugins/hid/__init__.py

@@ -37,6 +37,7 @@ from ...validators.basic import valid_string_list
 from ...validators.hid import valid_hid_key
 from ...validators.hid import valid_hid_mouse_move
 
+from ...keyboard.mappings import WebModifiers
 from ...mouse import MouseRange
 
 from .. import BasePlugin
@@ -148,10 +149,14 @@ class BaseHid(BasePlugin):  # pylint: disable=too-many-instance-attributes
             if no_ignore_keys or key not in self.__ignore_keys:
                 if slow:
                     await asyncio.sleep(0.02)
-                self.send_key_event(key, state)
+                self.send_key_event(key, state, False)
 
-    def send_key_event(self, key: str, state: bool) -> None:
+    def send_key_event(self, key: str, state: bool, finish: bool) -> None:
         self._send_key_event(key, state)
+        if state and finish and (key not in WebModifiers.ALL and key != "PrintScreen"):
+            # Считаем что PrintScreen это модификатор для Alt+SysRq+...
+            # По-хорошему надо учитывать факт нажатия на Alt, но можно и забить.
+            self._send_key_event(key, False)
         self.__bump_activity()
 
     def _send_key_event(self, key: str, state: bool) -> None:

web/kvm/index.html

@@ -285,7 +285,7 @@
             </tr>
           </table>
           <details>
-            <summary>Keyboard &amp; Mouse (HID) settings</summary>
+            <summary>Keyboard &amp; mouse (HID) settings</summary>
             <div class="spoiler">
               <table class="kv">
                 <tr>
@@ -401,6 +401,15 @@
             </div>
           </details>
           <table class="kv">
+            <tr>
+                  <td>Bad link mode (release keys immediately):</td>
+                  <td align="right">
+                    <div class="switch-box">
+                      <input type="checkbox" id="hid-keyboard-bad-link-switch">
+                      <label for="hid-keyboard-bad-link-switch"><span class="switch-inner"></span><span class="switch"></span></label>
+                    </div>
+                  </td>
+            </tr>
             <tr class="feature-disabled" id="hid-connect">
                   <td>Connect HID to Server:</td>
                   <td align="right">
@@ -420,7 +429,7 @@
                   </td>
             </tr>
             <tr>
-                  <td>Mute HID input events:</td>
+                  <td>Mute all input HID events:</td>
                   <td align="right">
                     <div class="switch-box">
                       <input type="checkbox" id="hid-mute-switch">

web/kvm/navbar-system.pug

@@ -85,7 +85,7 @@ li(id="system-dropdown" class="right")
 				td Mouse #[a(target="_blank" href="https://docs.pikvm.org/mouse") mode]:
 				td #[div(id="hid-outputs-mouse-box" class="radio-box")]
 		details
-			summary Keyboard & Mouse (HID) settings
+			summary Keyboard & mouse (HID) settings
 			div(class="spoiler")
 				table(class="kv")
 					tr
@@ -127,12 +127,14 @@ li(id="system-dropdown" class="right")
 					tr
 						+menu_switch_notable("page-full-tab-stream-switch", "Expand for the entire tab by default", true, false)
 		table(class="kv")
+			tr
+				+menu_switch_notable("hid-keyboard-bad-link-switch", "Bad link mode (release keys immediately)", true, false)
 			tr(id="hid-connect" class="feature-disabled")
 				+menu_switch_notable("hid-connect-switch", "Connect HID to Server", true, true)
 			tr(id="hid-jiggler" class="feature-disabled")
 				+menu_switch_notable("hid-jiggler-switch", "<a href=\"https://docs.pikvm.org/mouse_jiggler\" target=\"_blank\">Mouse jiggler</a>", false, false)
 			tr
-				+menu_switch_notable("hid-mute-switch", "Mute HID input events", true, false)
+				+menu_switch_notable("hid-mute-switch", "Mute all input HID events", true, false)
 			tr(id="v3-usb-breaker" class="feature-disabled")
 				+menu_switch_notable_gpio("__v3_usb_breaker__", "Connect main USB to Server",
 					"Turning off this switch will disconnect the main USB from the server.  Are you sure you want to continue?")

web/share/js/kvm/keyboard.js

@@ -52,6 +52,7 @@ export function Keyboard(__recordWsEvent) {
 		window.addEventListener("focusin", __updateOnlineLeds);
 		window.addEventListener("focusout", __updateOnlineLeds);
 
+		tools.storage.bindSimpleSwitch($("hid-keyboard-bad-link-switch"), "hid.keyboard.bad_link", false);
 		tools.storage.bindSimpleSwitch($("hid-keyboard-swap-cc-switch"), "hid.keyboard.swap_cc", false);
 	};
 
@@ -140,11 +141,16 @@ export function Keyboard(__recordWsEvent) {
 		}
 		let event = {
 			"event_type": "key",
-			"event": {"key": code, "state": state},
+			"event": {
+				"key": code,
+				"state": state,
+				"finish": $("hid-keyboard-bad-link-switch").checked,
+			},
 		};
 		if (__ws && !$("hid-mute-switch").checked) {
 			__ws.sendHidEvent(event);
 		}
+		delete event.event.finish;
 		__recordWsEvent(event);
 	};
 

web/share/js/kvm/recorder.js

@@ -336,7 +336,11 @@ export function Recorder() {
 				});
 				return;
 
-			} else if (["key", "mouse_button", "mouse_move", "mouse_wheel", "mouse_relative"].includes(event.event_type)) {
+			} else if (event.event_type === "key") {
+				event.event.finish = $("hid-keyboard-bad-link-switch").checked;
+				__ws.sendHidEvent(event);
+
+			} else if (["mouse_button", "mouse_move", "mouse_wheel", "mouse_relative"].includes(event.event_type)) {
 				__ws.sendHidEvent(event);
 
 			} else if (event.event_type === "mouse_move_random") {

web/share/js/kvm/session.js

@@ -316,6 +316,9 @@ export function Session() {
 		if (event_type == "key") {
 			let data = __ascii_encoder.encode("\x01\x00" + event.key);
 			data[1] = (event.state ? 1 : 0);
+			if (event.finish === true) { // Optional
+				data[1] |= 0x02;
+			}
 			ws.send(data);
 
 		} else if (event_type == "mouse_button") {