HTTP traffic via company MDM VPN tunnel #41500
Description
I'm trying to develop an in-house app for deployment within our company. This requires the use of a VPN tunnel which is provided by Mobile Iron (MDM solution). When I try to reach the internal API through Flutter I can see the app opens the VPN tunnel, but I'm getting an exception message that the connection failed using the following code (exact logs below):
import 'package:http/http.dart' as http;
// ...
var client = http.Client();
return await client.get(
'https://internal-api.internalcorp.net:8443/api/<!--redacted-->',
);The same issue exists using either the dart:io or the http package.
I tried implementing the HTTP calls in native iOS and call that via a method channel using the exact same details, and that seems to work okay. So I'm thinking that the http implementation in Flutter does something different than the native iOS http client via URLRequest:
let session = URLSession.shared
let url = URL(string: "https://internal-api.internalcorp.net:8443/api/<!--redacted-->")!
var request = URLRequest(url: url)
let task = session.dataTask(with: request) { data, response, error in
result([
"data": String(data: data!, encoding: .utf8)!,
"statusCode": (response as? HTTPURLResponse)?.statusCode
]);
}
task.resume()I'm not a Swift expert so the above code could probably be implemented in a better way.
PS: We only support iOS with our MDM solution, so I'm unable to test if the issue exists for Android as well.
Steps to Reproduce
I did not find a way to reproduce the issue outside of the company environment yet. I tried getting more insight on the network calls but can't find anything since the traffic is all encrypted via the tunnel.
Logs
Redacted a little to prevent exposing secure details.
[ +763 ms] [VERBOSE-2:ui_dart_state.cc(148)] Unhandled Exception: SocketException: Connection failed, address =
internal-api.internalcorp.net, port = 8443
[ ] #0 IOClient.send (package:http/src/io_client.dart:33:23)
[ ] <asynchronous suspension>
[ ] #1 BaseClient._sendUnstreamed (package:http/src/base_client.dart:169:38)
[ ] <asynchronous suspension>
[ ] #2 BaseClient.get (package:http/src/base_client.dart:32:7)
[ ] #3 Test.getData (package:example/test.dart:8:25)
[ ] <asynchronous suspension>
[ ] #4 _LoginPageState.build.<anonymous closure> (package:example/main.dart:160:53)
[ ] <asynchronous suspension>
[ ] #5 _InkResponseState._handleTap (package:flutter/src/material/ink_well.dart:635:14)
[ ] #6 _InkResponseState.build.<anonymous closure> (package:flutter/src/material/ink_well.dart:711:32)
[ ] #7 GestureRecognizer.invokeCallback (package:flutter/src/gestures/recognizer.dart:182:24)
[ ] #8 TapGestureRecognizer._checkUp (package:flutter/src/gestures/tap.dart:365:11)
[ ] #9 TapGestureRecognizer.handlePrimaryPointer (package:flutter/src/gestures/tap.dart:275:7)
[ ] #10 PrimaryPointerGestureRecognizer.handleEvent (package:flutter/src/gestures/recognizer.dart:455:9)
[ ] #11 PointerRouter._dispatch (package:flutter/src/gestures/pointer_router.dart:75:13)
[ ] #12 PointerRouter.route (package:flutter/src/gestures/pointer_router.dart:102:11)
[ ] #13 _WidgetsFlutterBinding&BindingBase&GestureBinding.handleEvent (package:flutter/src/gestures/binding.dart:218:19)
[ ] #14 _WidgetsFlutterBinding&BindingBase&GestureBinding.dispatchEvent (package:flutter/src/gestures/binding.dart:198:22)
[ +4 ms] #15 _WidgetsFlutterBinding&BindingBase&GestureBinding._handlePointerEvent (package:flutter/src/gestures/binding.dart:156:7)
[ ] #16 _WidgetsFlutterBinding&BindingBase&GestureBinding._flushPointerEventQueue (package:flutter/src/gestures/binding.dart:102:7)
[ ] #17 _WidgetsFlutterBinding&BindingBase&GestureBinding._handlePointerDataPacket (package:flutter/src/gestures/binding.dart:86:7)
[ ] #18 _rootRunUnary (dart:async/zone.dart:1136:13)
[ ] #19 _CustomZone.runUnary (dart:async/zone.dart:1029:19)
[ ] #20 _CustomZone.runUnaryGuarded (dart:async/zone.dart:931:7)
[ ] #21 _invoke1 (dart:ui/hooks.dart:250:10)
[ ] #22 _dispatchPointerDataPacket (dart:ui/hooks.dart:159:5)
[ +302 ms] [VERBOSE-2:shell.cc(184)] Dart Error: Unhandled exception:
[ ] Bad state: Future already completed
[ ] #0 _AsyncCompleter.complete (dart:async/future_impl.dart:39:31)
[ ] #1 _NativeSocket.startConnect.<anonymous closure>.connectNext.<anonymous closure> (dart:io-patch/socket_patch.dart:521:23)
[ ] #2 _NativeSocket.issueWriteEvent.issue (dart:io-patch/socket_patch.dart:874:14)
[ ] #3 _NativeSocket.issueWriteEvent (dart:io-patch/socket_patch.dart:881:12)
[ ] #4 _NativeSocket.multiplex (dart:io-patch/socket_patch.dart:902:11)
[ ] #5 _RawReceivePortImpl._handleMessage (dart:isolate-patch/isolate_patch.dart:172:12)
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