Manage SSH Keys - GitHub Action

Manage SSH authorized keys from GitHub with GitHub Actions.

This action will

1. Fetch public key from GitHub username e.g. https://github.com/dhsathiya.keys
2. Add provided users in keys.csv to the respective remote machines.

Note: This action is still under development, but works. Check TODO for more details

Why?

I get bore when I have to add a user or check the SSH access for someone.

With this action I can centrally monitor who can access what!

Configuration

1. create workflow directory and add yml file. .github/workflows/ssh_key.yml

   on:
     push:
       branches:
         - master
   
   name: Update SSH Keys
   jobs:
     Update-SSH-key:
       name: Update and sync files
       runs-on: ubuntu-latest
       steps:
       - uses: actions/checkout@v2
         with:
           fetch-depth: 2
       - name: Update and sync files
         uses: dhsathiya/action-ssh-keys@master
         env:
           DEPLOY_KEY: ${{secrets.DEPLOY_KEY}}

2. Create a GitHub secret named DEPLOY_KEY and add private key which will be used for rsync.

   • Create SSH keys https://help.github.com/en/github/authenticating-to-github/generating-a-new-ssh-key-and-adding-it-to-the-ssh-agent

3. Add the respective public key to the DEPLOY_KEY on all the machines on which you want to use this action.

4. Create file default.key in the GitHub repository root and add the public key in it.

   • This step is necessary, so that the SSH key used by action gets whitelisted on every run.
   • Other reason is, you are using this action because you don't like manual stuff and you also won't like to add the step 3 key after every run. 😉

5. Create keys.csv file.

   • Simple csv file, field separated with ,

keys.csv file format

user@hostname	/path/to/authorized_keys
root@dev.sitename.tld	/root/.ssh/authorized_keys	user1	user2
www-data@prod.sitename.tld	/var/www/.ssh/authorized_keys	user1	user2	user3	user4

The action will by default ignore first line.

Example CSV File

TODO

• Checks and filters for CSV file fields
• Only run on diff
• Fail checks
• Feature: Direct SSH key support
• Make action code as per best practices
• Lighter Docker image
• HashiCorp Vault Support
• Publish Action
• Slack Notification

License

MIT © 2020 Devarshi Sathiya