[X2Go-User] ssh connection through bastion host

[Hauke Fath]

On Thu, 27 Jun 2024 10:49:48 +0200, Hauke Fath wrote:
>> Also, x2goclient knows some debug switches to produce log files. You
>> might see what's going on.
> 
> I might, if I could find said debug switches, which is what my question 
> was about... Please fill me in.

I managed to invoke the mac x2go client from the command line as 
'./x2go --libssh-debug', which gives a bit more information.

A lot of it is of the form "ssh_config_parse_line: 
Un(supported|applicable) option:", to the point where a list of libssh 
supported options will probably be shorter... In particular, ProxyJump 
is not supported.

The debug information ends with

[...]
[2024/06/27 11:46:22.944213, 1] ssh_agent_get_ident_count:  Answer 
type: 12, expected answer: 12
[2024/06/27 11:46:23.238705, 2] channel_open:  Creating a channel 43 
with 64000 window and 32768 max packet
[2024/06/27 11:46:23.262887, 2] ssh_packet_global_request:  Received 
SSH_MSG_GLOBAL_REQUEST packet
[2024/06/27 11:46:23.262971, 2] ssh_packet_global_request:  UNKNOWN 
SSH_MSG_GLOBAL_REQUEST hostkeys-00 at openssh.com 0
[2024/06/27 11:46:23.262988, 1] ssh_packet_process:  Couldn't do 
anything with packet type 80
[2024/06/27 11:46:23.263056, 2] ssh_packet_ignore_callback:  Received 
SSH_MSG_DEBUG packet
[2024/06/27 11:46:23.263078, 2] ssh_packet_ignore_callback:  Received 
SSH_MSG_DEBUG packet
[2024/06/27 11:46:23.287345, 2] ssh_packet_channel_open_conf:  Received 
a CHANNEL_OPEN_CONFIRMATION for channel 43:0
[2024/06/27 11:46:23.287401, 2] ssh_packet_channel_open_conf:  Remote 
window : 0, maxpacket : 32768
[2024/06/27 11:46:23.532003, 1] channel_request:  Channel request 
pty-req failed


and while the jumphost logs


Jun 27 11:51:29 Pollux sshd[22590]: SSH: Server;Ltype: Kex;Remote: 
195.52.168.252-61842;Enc: aes256-ctr;MAC: hmac-sha2-256;Comp: none 
[preauth]
Jun 27 11:51:30 Pollux sshd[22590]: SSH: Server;Ltype: Authname;Remote: 
195.52.168.252-61842;Name: ntjump [preauth]
Jun 27 11:51:30 Pollux sshd[22590]: Accepted publickey for ntjump from 
195.52.168.252 port 61842 ssh2: RSA 
SHA256:e593oJRD2akRZtNT3ib5VufkJc3RCRdGEqDlfV+xKNU
Jun 27 11:51:30 Pollux sshd[25939]: SSH: Server;LType: 
Throughput;Remote: 195.52.168.252-61842;IN: 0;OUT: 0;Duration: 
0.3;tPut_in: 0.0;tPut_out: 0.0


there is no indication of a connection to the target machine, neither 
on the jumphost, nor the target machine's logs.

Cheerio,
Hauke

-- 
     The ASCII Ribbon Campaign                    Hauke Fath
()     No HTML/RTF in email            Institut für Nachrichtentechnik
/\     No Word docs in email                     TU Darmstadt
     Respect for open standards              Ruf +49-6151-16-21344