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+# factoriauth - an unofficial [Factorio](https://factorio.com) authentication server
+
+Let's say you and your friends are
+- on an oil rig,
+- in space, or
+- in the far future,
+
+and you want to host a Factorio server. Because you don't have an internet connection (or the
+official authentication servers don't exist anymore), your only option is to disable
+`require_user_verification` in the server config - but this allows anyone to connect as any user,
+which is no good, especially for PvP scenarios! Wouldn't it be great if you could set up your own
+authentication server?
+
+factoriauth is exactly that. It allows clients to log in as custom users provided by one of several
+authentication backends (e.g. LDAP or a passwd-style file), and allows servers to validate that
+these custom users are properly authenticated.
+
+## Roadmap
+
+### Complete
+
+Nothing yet!
+
+### Planned
+
+- [user token generation](https://wiki.factorio.com/Web_authentication_API) (`POST /api-login`)
+    - auth backends: LDAP, user file, PAM(?)
+- server padlock generation (`POST /generate-server-padlock-2`)
+- `user_server_key` generation (`POST /generate-user-server-key-2`)
+- server padlock proxying (to allow e.g. factorio.com users to join servers using a custom auth
+  server)
+
+### Unplanned
+
+- [updater server functionality](https://wiki.factorio.com/Download_API)
+- [mods server functionality](https://wiki.factorio.com/Mod_portal_API)
+- [multiplayer lobby server functionality](https://wiki.factorio.com/Matchmaking_API)
+
+## Setup
+
+### Configuring factoriauth
+
+TBD
+
+### Configuring clients/servers
+
+To use the auth server, the following snippet needs to be added to the clients' and servers'
+`config.ini`, replacing the URL of the server as appropriate:
+
+```ini
+[servers]
+auth-server=https://my-auth-server.example/
+```
+
+### Running factoriauth
+
+TBD