About

A server-side mod that allow to use muliple auth source, exactly like MultiYggdrasil, for older versions.

Configuration

To configure the mod, open config/multiauth/auth_servers.json the default one seem to :

[
    {
        "name": "Mojang/Microsoft",
        "url": "https://sessionserver.mojang.com"
    }
]

To add an auth source, just copy paste the object and replace url and name by yours

Question ?

• do is skin work ? [W.I.K]
• do is compatible with auhlib-injector ? Yes
• do is compatible with ely.by, drasl.unmojang.org ? Yes

Want to discuss or help me ? Join my discord : https://discord.gg/cU5hgc79qE

MultiAuth

MultiAuth is a Forge mod allowing Minecraft servers to accept connections from multiple Yggdrasil authentication services simultaneously.

✨ Features

• Multi-Yggdrasil Support: Connect to any number of auth services (Mojang, private, etc.).
• Discovery Protocol: Instant auth-provider identification via custom network packets.
• UUID Namespacing: Deterministic UUID generation to prevent inventory collisions between providers.
• Duplicate Handling: Optional @index aliasing for users with identical names.
• Smart Caching: Remembers player auth sources to speed up login.
• Skin Validation: Full RSA signature verification for all providers.

🛠 Configuration (multiauth.json)

Located in your config/ folder.

{
    "server": [
        {
            "name": "Mojang's Session Server",
            "url": "https://sessionserver.mojang.com"
        },
        {
            "name": "Azures04's Servers",
            "url": "https://yggdrasil.azures.fr"
        }
    ],
    "cache": true,
    "allowDuplicateNames": true
}

• server: Authorized auth services (order determines @index alias).
• cache: Save successful login sources.
• allowDuplicateNames: Allow identical usernames via aliasing.