Teleport does not set terminal size correctly on connection

[aashley]

What happened: Terminal size is not set correctly and text wrapping does not work correctly. Fix for #1087 does not work.

What you expected to happen: Text to wrap correctly as per every other terminal app.

How to reproduce it (as minimally and precisely as possible):

adama@swiftdesk6:~$ tsh version
Teleport v2.4.1 git:v2.4.1-0-gf90cc7c
adama@swiftdesk6:~$ tput cols
90
adama@swiftdesk6:~$ tput lines
57
adama@swiftdesk6:~$ tsh --proxy=teleport.local --cluster=od003 ssh root@od003
root@od003:~# tsh version
Teleport v2.4.1 git:v2.4.1-0-gf90cc7c
root@od003:~# tput cols
80
root@od003:~# tput lines
24
root@od003:~# 

This was run in gnome-terminal and mate-terminal as per my original comments on #1087 with the same failure results

Environment:

• Teleport version (use teleport version): Teleport v2.4.1 git:v2.4.1-0-gf90cc7c
• Tsh version (use tsh version): Teleport v2.4.1 git:v2.4.1-0-gf90cc7c
• OS (e.g. from /etc/os-release): Ubuntu 16.04.3 LTS

Browser environment

• Browser Version (for UI-related issues):
• Install tools:
• Others:

Relevant Debug Logs If Applicable

• tsh --debug
• teleport --debug

[aashley]

Screenshot of the terminal performing the above tests https://i.imgur.com/mgdcd2Y.png

[aashley]

And performing the same test in the same terminal via SSH to the same host.

adama@swiftdesk6:~$ ssh -p 23003 [email protected] 
[email protected]'s password: 
Welcome to Ubuntu 16.04.3 LTS (GNU/Linux 4.13.0-32-generic x86_64)
Last login: Fri Feb 16 09:36:41 2018 from ::1
root@od003:~# tput cols
90
root@od003:~# tput lines
57
root@od003:~# 

[klizhentas]

@russjones is this the same issue you fixed by #1567 or a different one?

[aashley]

I think the fix he did in #1567 fixed it for mac terminals but it didn't make a difference for the others mentioned in #1087. Certainly the behaviour of tsh before and after #1567 has not changed on linux builds within any terminal software I've tried.

[klizhentas]

@russjones thoughts?

[kontsevoy]

@aashley is that gnome-terminal you're using?

[russjones]

@aashley I was able to reproduce this using Ubuntu 16.04 and GNOME Terminal 3.18.3. I'll investigate.

[russjones]

I did some more investigation into this, this only seems to be a problem when using the recording proxy and connecting to a Teleport node. Otherwise terminals are re-sized as expected.

	Teleport Node	OpenSSH Node
Regular Proxy	✔	✔
Recording Proxy	✖	✔

@aashley With what configuration are you running into this problem?

[aashley]

We're using Teleport Node with recording proxy.

Our setup is lots of remote deployed machines on other networks behind NAT firewalls so we use a cloud master with each site being a trusted cluster. Using the recording proxy to maintain logs of the sessions in the cloud master instance as apposed to each individual deployed server.

[russjones]

@aashley Fixed this in #1706. The fix will be in both 2.5.0 and 2.4.2.