X2Go Bug report logs - #1258
x2goclient hangs when connecting with Kerberos auth

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Package: x2goclient; Maintainer for x2goclient is X2Go Developers <x2go-dev@lists.x2go.org>; Source for x2goclient is src:x2goclient.

Reported by: Mike DePaulo <mikedep333@gmail.com>

Date: Mon, 19 Feb 2018 04:30:02 UTC

Severity: normal

Tags: pending

Found in version

Fixed in version

Done: X2Go Release Manager X2Go Release Manager <git-admin@x2go.org>

Bug is archived. No further changes may be made.

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Subject: Bug#1258: x2goclient hangs when connecting with Kerberos auth
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From: Mike DePaulo <mikedep333@gmail.com>
Date: Sun, 18 Feb 2018 23:28:12 -0500
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Package: x2goclient

When attempting to connect to an X2Go server with GSSAPI/Kerberos
auth, x2goclient hangs indefinitely.

This was observed with nightly builds for Windows, and was assumed to
be Windows-specific.

The fix has already been committed to master. I will update master
with another commit (& change to debian/changelog) stating that this
was fixed:
commit 7cbd8d525309edb8bd05d27ec57ac72e2d8c90e8
Author: Mike DePaulo <mikedep333@gmail.com>
Date:   Sun Feb 18 19:52:22 2018 -0500

    Do not attempt to perform Interaction with SSH Server

    (e.g. for changing expired password) when using GSSAPI/Kerberos
    because the interaction code does not support it yet.

But as I was fixing it, I noticed that Linux & Mac OS X are probably
affected too.

The cause of the issue is that the new Interaction Dialog feature
introduced by this commit contains libssh-specific function calls, but
we use PuTTY binaries on Windows & the OpenSSH ssh client binary on
Linux/MacOS for GSSAPI/Kerberos:
commit 68bbf328132125eaad5c53b0ac82490bf818e42e
Author: Oleksandr Shneyder <o.shneyder@phoca-gmbh.de>
Date:   Wed May 10 15:22:11 2017 +0200

    Interaction with SSH server (for example for changing expired
password). Fixes: #592.

And the "fix" for this is to bypass that new feature when
GSSAPI/Kerberos auth is used.

I will open up a separate issue about the fact that the Interaction
Dialog feature does not work with GSSAPI/Kerberos.


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