[X2Go-User] Login via ~/.ssh/authorized_keys fails

[Matthias Kauer]

Hi,
I am looking for input on how to set up an ssh key-based authentication.

I generated an RSA key pair with puttygen and added it to
~/.ssh/authorized_keys2 => confirmed that I can login with putty.
Now, I specify the same private key in x2goclient (windows). I enter my
password and I am then prompted for the password of the ssh key. I enter
it and the same ssh key password prompt reappears. This seems to be an
infinite loop. When I cancel it, I get a message saying that only
publickey is supported as login method (which corresponds to my
sshd_config settings).

I then tried renaming ~/.ssh/authorized_keys and using a DSA key pair.
putty still works as expected with both of these alternatives.
x2goclient still shows the same problems however. It only lets me login
if I adapt my sshd_config and authenticate via user / password combination.

Is this a known limitation?
What is the best way to achieve high security? Can I limit the x2go
connections to only LAN IPs (without restricting the pure ssh connections)?

Best Wishes,
Matthias Kauer