juxt / rock

Hardened AMIs for Clojure deployments (Arch Linux)

Rock

Rock is a project to build an AMI built on Arch Linux that is suitable for Java and Clojure projects.

See https://wiki.archlinux.org/title/Arch_Linux_AMIs_for_Amazon_Web_Services

Building an AMI

AWS_PROFILE=<profile> make

Copyright & License

The MIT License (MIT)

Copyright © 2018-2023 JUXT LTD.

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

rock's Issues

Disable root login over SSH

This is enabled in the default Arch AMI and hasn't been disabled by us.

Injecting an sshd_config will do the trick.

PermitRootLogin no

Probably also a good idea to double check password auth is disabled, maybe move off the default port of 22, and if this is running on a publicly-accessible box use something like fail2ban?

Maybe swap out log forwarder

systemd-cloud-watch looks a little bit broken, and although there's a fix in advantageous/systemd-cloud-watch#16, I'm not sure how long until that gets merged.

We have a couple of options:

1. Wait for the PR to be merged;
2. Change the systemd-cloud-watch package to pull from GitHub and use the fork with fixes;
3. Switch to the shell script approach used in some other places.

In the meantime I've commented out starting up the log forwarding service in #4.

Write CodeDeploy logs to journald

According to CodeDeploy's docs, log output goes to a file on disk, which likely won't be log rotated.

/var/log/aws/codedeploy-agent/codedeploy-agent.log

If we can instead log to stdout, that'll go via journald and be forwarded anywhere we need etc.