Re: AW: [SUPPORT REQUEST] Configuration of libssh host key algos on client

[Anderson Sasaki <ansasaki@xxxxxxxxxx>]

----- Original Message -----
> From: "Sebastian Kraust" <sebastian.kraust@xxxxxxxxxx>
> To: libssh@xxxxxxxxxx
> Sent: Monday, May 25, 2020 6:54:57 PM
> Subject: AW: [SUPPORT REQUEST] Configuration of libssh host key algos on client
> 
> Hi Anderson,
> 
> thanks for your reply.
> 
> I have copied /etc/ssh/sshd_config tot he directory you specified, e.g. as I
> am root on the client, I put it under /root/.ssh/sshd_config and restarted
> the service via
> 
> service sshd restart
> 
> Unfortunately, I get the same error. Maybe it helps you to take a look at the
> whole config file, which I attached to this email.


Sorry, But haven't you said you are modifying the client configuration as it is the only part you can modify?
If it is still the case, copy the configuration to /root/.ssh/config (without sshd_) and try again. You don't need to reload the server.

If you can modify the server, I would strongly suggest you to follow Jakub's advice and change the algorithms it is using.

Regards,
Anderson

> 
> Regards,
> Sebastian
> 
> -----Ursprüngliche Nachricht-----
> Von: Anderson Sasaki <ansasaki@xxxxxxxxxx>
> Gesendet: Montag, 25. Mai 2020 18:37
> An: libssh@xxxxxxxxxx
> Betreff: Re: [SUPPORT REQUEST] Configuration of libssh host key algos on
> client
> 
> NOTICE: This message originated from outside of the company. Please exercise
> caution when replying or opening links and attachments.
> 
> 
> 
> 
> ----- Original Message -----
> > From: "Sebastian Kraust" <sebastian.kraust@xxxxxxxxxx>
> > To: libssh@xxxxxxxxxx
> > Sent: Monday, May 25, 2020 5:52:15 PM
> > Subject: [SUPPORT REQUEST] Configuration of libssh host key algos on
> > client
> >
> > Hello libssh-team,
> >
> > I am currently working on a project using libssh under the hood, but
> > have problems to get it to work. I hope you can provide some help.
> >
> > Task
> > Write a client for an existing server which cannot be
> > changed/configured by me.
> >
> > Approach
> > Connect to the server using the function `ssh_connect`.
> >
> > Error
> > kex error : no match for method server host key algo: server
> > [ssh-rsa], client
> > [ssh-ed25519,ecdsa-sha2-nistp521,ecdsa-sha2-nistp384,ecdsa-sha2-nistp2
> > 56,rsa-sha2-512,rsa-sha2-256]
> >
> > Problem
> > Due to the restriction that I can only change the client side, I have
> > to change the client so that it accepts the ssh-rsa algo.
> > According to the docs, it should be capable of doing so.
> >
> > Troubleshooting so far
> > Added
> > PubkeyAcceptedKeyTypes ssh-ed25519*,ssh-rsa*,ssh-dss*,ecdsa-sha2
> > to /etc/ssh/sshd_config to allow every algo on the client side.
> >
> > I still get the same error. I do believe that the config might not be
> > the correct file to configure libssh.
> >
> > Can you give me some direction where I have to configure libssh so
> > that the client also accepts the ssh-rsa algorithm? If you need more
> > information, please let me know.
> 
> Hello,
> 
> Have you tried to add the configuration locally at user's ~/.ssh/config file?
> 
> Regards,
> Anderson
> 
> 
>