Merge PR #1450

helper/helper/device.py

@@ -42,6 +42,7 @@ from yubikit.logging import LOG_LEVEL
 from ykman.pcsc import list_devices, YK_READER_NAME
 from smartcard.Exceptions import SmartcardException, NoCardException
 from smartcard.pcsc.PCSCExceptions import EstablishContextException
+from smartcard.CardMonitoring import CardObserver, CardMonitor
 from hashlib import sha256
 from dataclasses import asdict
 from typing import Mapping, Tuple
@@ -263,9 +264,6 @@ class AbstractDeviceNode(RpcNode):
 
 
 class UsbDeviceNode(AbstractDeviceNode):
-    def __init__(self, device, info):
-        super().__init__(device, info)
-
     def _supports_connection(self, conn_type):
         return self._device.pid.supports_connection(conn_type)
 
@@ -308,15 +306,53 @@ class UsbDeviceNode(AbstractDeviceNode):
             raise ConnectionException("fido", e)
 
 
+class _ReaderObserver(CardObserver):
+    def __init__(self, device):
+        self.device = device
+        self.card = None
+        self.data = None
+
+    def update(self, observable, actions):
+        added, removed = actions
+        for card in added:
+            if card.reader == self.device.reader.name:
+                if card != self.card:
+                    self.card = card
+                break
+        else:
+            self.card = None
+        self.data = None
+        logger.debug(f"NFC card: {self.card}")
+
+
 class ReaderDeviceNode(AbstractDeviceNode):
+    def __init__(self, device, info):
+        super().__init__(device, info)
+        self._observer = _ReaderObserver(device)
+        self._monitor = CardMonitor()
+        self._monitor.addObserver(self._observer)
+
+    def close(self):
+        self._monitor.deleteObserver(self._observer)
+        super().close()
+
     def get_data(self):
-        try:
-            with self._device.open_connection(SmartCardConnection) as conn:
-                return dict(self._read_data(conn), present=True)
-        except NoCardException:
-            return dict(present=False, status="no-card")
-        except ValueError:
-            return dict(present=False, status="unknown-device")
+        if self._observer.data is None:
+            card = self._observer.card
+            if card is None:
+                return dict(present=False, status="no-card")
+            try:
+                with self._device.open_connection(SmartCardConnection) as conn:
+                    self._observer.data = dict(self._read_data(conn), present=True)
+            except NoCardException:
+                return dict(present=False, status="no-card")
+            except ValueError:
+                self._observer.data = dict(present=False, status="unknown-device")
+        return self._observer.data
+
+    @action(closes_child=False)
+    def get(self, params, event, signal):
+        return super().get(params, event, signal)
 
     @child
     def ccid(self):

lib/desktop/devices.dart

@@ -31,9 +31,8 @@ import 'state.dart';
 
 const _usbPollDelay = Duration(milliseconds: 500);
 
-const _nfcPollDelay = Duration(milliseconds: 2500);
-const _nfcAttachPollDelay = Duration(seconds: 1);
-const _nfcDetachPollDelay = Duration(seconds: 5);
+const _nfcPollReadersDelay = Duration(milliseconds: 2500);
+const _nfcPollCardDelay = Duration(seconds: 1);
 
 final _log = Logger('desktop.devices');
 
@@ -197,7 +196,7 @@ class NfcDeviceNotifier extends StateNotifier<List<NfcReaderNode>> {
     }
 
     if (mounted) {
-      _pollTimer = Timer(_nfcPollDelay, _pollReaders);
+      _pollTimer = Timer(_nfcPollReadersDelay, _pollReaders);
     }
   }
 }
@@ -260,7 +259,7 @@ class CurrentDeviceDataNotifier extends StateNotifier<AsyncValue<YubiKeyData>> {
 
   void _notifyWindowState(WindowState windowState) {
     if (windowState.active) {
-      _pollReader();
+      _pollCard();
     } else {
       _pollTimer?.cancel();
       // TODO: Should we clear the key here?
@@ -276,16 +275,23 @@ class CurrentDeviceDataNotifier extends StateNotifier<AsyncValue<YubiKeyData>> {
     super.dispose();
   }
 
-  void _pollReader() async {
+  void _pollCard() async {
     _pollTimer?.cancel();
     final node = _deviceNode!;
     try {
-      _log.debug('Polling for USB device changes...');
+      _log.debug('Polling for NFC device changes...');
       var result = await _rpc?.command('get', node.path.segments);
       if (mounted && result != null) {
         if (result['data']['present']) {
-          state = AsyncValue.data(YubiKeyData(node, result['data']['name'],
-              DeviceInfo.fromJson(result['data']['info'])));
+          final oldState = state.valueOrNull;
+          final newState = YubiKeyData(node, result['data']['name'],
+              DeviceInfo.fromJson(result['data']['info']));
+          if (oldState != null && oldState != newState) {
+            // Ensure state is cleared
+            state = const AsyncValue.loading();
+          } else {
+            state = AsyncValue.data(newState);
+          }
         } else {
           final status = result['data']['status'];
           // Only update if status is not changed
@@ -298,9 +304,7 @@ class CurrentDeviceDataNotifier extends StateNotifier<AsyncValue<YubiKeyData>> {
       _log.error('Error polling NFC', jsonEncode(e));
     }
     if (mounted) {
-      _pollTimer = Timer(
-          state is AsyncData ? _nfcDetachPollDelay : _nfcAttachPollDelay,
-          _pollReader);
+      _pollTimer = Timer(_nfcPollCardDelay, _pollCard);
     }
   }
 }

lib/desktop/oath/state.dart

@@ -295,7 +295,7 @@ class DesktopCredentialListNotifier extends OathCredentialListNotifier {
         code = OathCode.fromJson(result);
       }
       _log.debug('Calculate', jsonEncode(code));
-      if (update && mounted) {
+      if (update && mounted && state != null) {
         final creds = state!.toList();
         final i = creds.indexWhere((e) => e.credential.id == credential.id);
         state = creds..[i] = creds[i].copyWith(code: code);