SSH and git forges

The process is pretty much the same across Forgejo-ish services and Github.

Codeberg: https://docs.codeberg.org/security/ssh-key/

github: https://docs.github.com/en/authentication/connecting-to-github-with-ssh

Tangled has awful documentation but works pretty much the same.

  1. cd ~/.ssh.

  2. Generate a fresh key with ssh-keygen -t ed25519 -a 100 or similar.

    • I like to give each key a name and use one key per service, instead of the default id_ed25519 key

  3. Paste the public half of the key (the .pub file) into the git forge’s settings.

  4. In .ssh/config (create if it doesn’t exist), tell SSH to use the right key when connecting to a host:

    Host codeberg.org
  HostName codeberg.org
  User git
  IdentityFile ~/.ssh/my-awesome-key
    • Host codeberg.org means you can talk about this host using codeberg.org, e.g. ssh codeberg.org on the command line.
    • Both Forgejo and Github make everyone connect through the same SSH user named git. Actual users are differentiated based off the public key. Setting this value in the ssh config file means it doesn’t have to be mentioned everywhere, e.g. ssh codeberg.org instead of ssh git@codeberg.org.
    • IdentityFile sets the key to use for the ssh connection.

  5. Test the connection with ssh -T codeberg.org.

    • -T means SSH doesn’t do any virtual terminal stuff; makes sense since these git forges don’t actually provide a terminal.
    • Tangled doesn’t seem to offer a test service.

  6. Fix up any git remote URLs.

Codeberg seems to want this format: ssh://git@codeberg.org/quat/mods.git

Github (and Tangled) seems to want this format: git@github.com:quat1024/mods.git / git@tangled.sh:highlysuspect.agency/mods

I am not sure if they are interchangeable after doing some more url-fiddling? prefixing the github-style URL with ssh:// just broke it.