SSHAuthAbortError(Connection closed before authentication) when using jumpServer

[mostcute]

import 'dart:convert';

import 'package:dartssh2/dartssh2.dart';

void main() async {
  final jumpServer = SSHClient(
    await SSHSocket.connect('pubnetip  on HostA', 22222),
    username: 'root',
    onPasswordRequest: () => 'xxxxx',
  );
  print("jumpServer ");

  final client = SSHClient(
    await jumpServer.forwardLocal('internal ip on HostB', 22),
    username: 'root',
    onPasswordRequest: () => 'xxxxx',
  );
  print("client ");
  print(utf8.decode(await client.run('hostname')));
  print(utf8.decode(await client.run('ifconfig')));
  print("client close");
  client.close();
  jumpServer.close();
}

the code can work sometimes,but it will meet err mosttime

E/flutter (22717): [ERROR:flutter/runtime/dart_vm_initializer.cc(41)] Unhandled Exception: SSHAuthAbortError(Connection closed before authentication)

[DevAloshe]

same error ):

[XavierChanth]

After client = SSHClient(...);, try:

  try {
    // Ensure we are connected and authenticated correctly
    await client.ping().catchError((e) => throw e);
  } catch (e, s) {
    // Handle SSH auth errors here
  }

Initially, I had:

  try {
    // Ensure we are connected and authenticated correctly
    await client.authenticated.catchError((e) => throw e);
  } catch (e, s) {
    // Handle SSH auth errors here
  }

but I was experiencing the same SSHAuthAbortError when I did that.
This sends a keep alive to the server, in addition to waiting for authentication to complete.

[wukgdu]

could check the version of ssh server
this lib checks SSH2 in meta data received from the server, so if the ssh server is 1.x，SSHAuthAbortError(Connection closed before authentication) will occur

[aqueebqazi]

try this
final client = SSHClient(
await SSHSocket.connect('localhost', 22),
username: '',
onPasswordRequest: () => '',
);