SSH host key algorithms

[neingeist]

What happened?

I set up DevPod (with mrsimonemms/devpod-provider-hetzner) and this worked beautifully, except I couldn't connect with SSH, which also breaks using VSCode (not the browser version).

It turns out that I needed special SSH configuration: HostKeyAlgorithms rsa-sha2-256,rsa-sha2-512,ssh-rsa for DevPod, because I have my ssh configured to use HostKeyAlgorithms ssh-ed25519-cert-v01@openssh.com,ssh-ed25519 (via Match final all).

What did you expect to happen instead?

That DevPod's SSH server provides ED25519. Or that the generated SSH client configuration sets HostKeyAlgorithms properly.

How can we reproduce the bug? (as minimally and precisely as possible)

Use this in .ssh/config:

Match final all
  HostKeyAlgorithms ssh-ed25519-cert-v01@openssh.com,ssh-ed25519

Local Environment:

• DevPod Version: 0.5.4
• Operating System: linux
• ARCH of the OS: AMD64

DevPod Provider:

• Cloud Provider: hetzner
• Kubernetes Provider: (none)
• Local/remote provider: ssh

Anything else we need to know?
I am not sure if the custom provider (Hetzner) changes anything.

[neingeist]

Workaround I found: I placed this in .ssh/config, before DevPod's part:

Match host="*.devpod"
  HostKeyAlgorithms rsa-sha2-256,rsa-sha2-512,ssh-rsa

[neingeist]

Other than this DevPod works nicely, even with my exotic provider! 🤩

[pascalbreuninger]

@neingeist thanks for opening the issue! We'll take a look at it but good thing you've found a workaround - might be useful for others in the future as well

[neingeist]

ssh (the client) is fixed but VSCode chokes on the above workaround, for now using this instead:

Host *.devpod
     HostKeyAlgorithms rsa-sha2-256,rsa-sha2-512,ssh-rsa

AFAICT, this must be above DevPods other configuration for the project.