ssh-allowed_signers/README.md

# allowed_signers file for SSH/git

Git 2.34 brings support for signing commits with SSH key and having a SSH-compatible
smartcard, I have to try this. It likely getting more common in the future doesn't
hurt either and I have [pgp-alt-wot](https://gitea.blesmrt.net/Mikaela/pgp-alt-wot)
which does about the same for PGP.

## Where to find keys

* GitHub, Giteas and GitLabs expose user public keys (without useful names)
  when you append a `.keys` after their profile page
  * For example: https://github.com/Mikaela.keys https://gitea.blesmrt.net/Mikaela.keys https://gitlab.com/Mikaela.keys
* Good ideas are made to be copied, so maybe there will be more repositories like this :wink:

## Quick howto

I don't mean this to be used directly, only to be took inspiration from. See the first
link in further reading.

```bash
mkdir -p ~/src/gitea.blesmrt.net/Mikaela
cd ~/src/gitea.blesmrt.net/Mikaela
git clone https://gitea.blesmrt.net/Mikaela/ssh-allowed_signers.git
git config --global gpg.ssh.allowedSignersFile ~/src/gitea.blesmrt.net/Mikaela/ssh-allowed_signers/allowed_signers
```

Git commands, such as `git verify-commit --raw HEAD` or `git log --show-signature`,
should now recognised commits signed with keys I have allowed.
In the last command it's fine to remove `--global` to only affect the single
repository you are on (while I haven't tested this), should that repository
be something only I am signing in or something I need to verify otherwise
enough to list it here.

On the last command, `git config` turns it into absolute path, while manually
edited `.gitconfig` can literally have the above. I wonder if the command
would understand `--` before the file, but not enough to actually try it :smiley:

## Mirrors

* https://gitea.blesmrt.net/mikaela/ssh-allowed_signers
* https://github.com/mikaela/ssh-allowed_signers
* https://gitlab.com/mikaela/ssh-allowed_signers
* https://git.com.de/mikaela/ssh-allowed_signers & http://gitea.qzzf2qcfbhievvs5nzkccuwddroipy62qjocqtmgcgh75vd6w57m7yad.onion/Mikaela/ssh-allowed_signers

## Further reading

* [Caleb Hearth: Signing Git Commits with Your SSH Key](https://calebhearth.com/sign-git-with-ssh) ([web.archive.org](https://web.archive.org/web/20211117182628/https://calebhearth.com/sign-git-with-ssh)) inspired me to try this
* [Andrew Ayer: It's Now Possible To Sign Arbitrary Data With Your SSH Keys](https://www.agwa.name/blog/post/ssh_signatures) instructs on signing and verifying files outside of git

### Forge support

* 🥇 [Gitea v1.16.0 brought support for SSH signed commits on 2022-01-30.](https://blog.gitea.io/2022/02/gitea-1.16.0-and-1.16.1-released/) ([tag](https://github.com/go-gitea/gitea/releases/tag/v1.16.0))
  * [Their Git hosting comparison also includes SSH Signed Commits](https://docs.gitea.io/en-us/comparison/#code-management).
* [GitHub feedback: Allow using SSH keys to sign commits](https://github.com/github/feedback/discussions/7744)
  * TODO: notify here when it actually works, link to their guide or maybe remove the section?
* [GitLab issues: Support for SSH signed commits](https://gitlab.com/gitlab-org/gitlab/-/issues/343879) and [a draft merge request on the subject](https://gitlab.com/gitlab-org/gitlab/-/merge_requests/78200)
  * TODO: (a) better link(s) when this happens