AltAuth is a solution to allow players with Mojang account, (untested) banned accounts and (untested) Multiplayer disabled accounts to join online mode Minecraft servers depending on client and server support. This works by redirecting the session server requests to a proxy specified by the server.
In comparison to the trustless authentication method proposed by Aizistral https://github.com/Aizistral-Studios/Trustless-Authentication this authentication method enables joining of Mojang account players, prevents man in the middle attacks (like vanilla authentication) and is compatible to clients without AltAuth, but requires a trusted third/second party.
The build/libs/AltAuth-*-all.jar (produced by running ./gradlew build) is a valid Fabric (client and server 1.19.2),
Bukkit/Spigot/Paper (1.8 - 1.19.2) and BungeeCord/Waterfall mod/plugin. The server needs to be in online mode and
specify the domain or ip address of an AltAuth web proxy.
Since https is a requirement and the example proxy proxy.py not yet supporting https the proxy has to run behind a
https reverse proxy currently. Configuration of the proxy can be done in the first lines of the proxy script.
Banned and multiplayer disabled user support have not been tested yet and are therefore disabled by default.
