Avoid using APT to generate SSH host keys #16
Conversation
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Techniques that leverage the openssh-server package’s postinst script
risk two conflicts:
- When ssh.service has been started by APT, attempting to trigger the
postinst script by starting another instance of APT deadlocks.
- When ssh.service has been started manually, the postinst script in
the unit dependency causes the proximal activation to be canceled.
To avoid these complications, invoke ssh-keygen directly. The -A option
does exactly what we need:
> Generate host keys of all default key types (rsa, ecdsa, and ed25519)
> if they do not already exist.
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
1 participant
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
Techniques that leverage the
openssh-serverpackage’spostinstscript risk two conflicts:When
ssh.servicehas been started by APT, attempting to trigger thepostinstscript by starting another instance of APT deadlocks.When
ssh.servicehas been started manually, thepostinstrun viassh-hostkey-generate.servicecauses the proximal activation ofssh.serviceto be canceled, and e.g. Ansible tasks to fail.To avoid these complications, invoke
ssh-keygendirectly. The-Aoption does exactly what we need: