Login Daddy

A Fabric mod for private friend servers (Mainly Offline-Mode servers). Requires players to have the mod installed on their client, be on the whitelist of this mod (not the server whitelist) and authenticate with a password before they can play.

How it works

Player connects → sent to an invisible limbo dimension
Server checks if the client has LoginDaddy installed (handshake). No mod = kicked
Client is prompted to enter the server key (if one is configured). Wrong key = kicked
Server checks if the player is whitelisted. Not whitelisted = kicked
If the player has a valid session (logged in within the last 48 hours from the same IP), they are released automatically
Otherwise, player registers or logs in with a password
Player is teleported back to where they joined from

Join/leave messages and tab list are hidden until authentication is complete.

Requirements

Minecraft 1.21.11
Fabric Loader 0.18.2+
Fabric API

Setup

Server

Drop the mod jar into your mods/ folder
Start the server once to generate config/LoginDaddy/logindaddy.properties
Edit logindaddy.properties with your database credentials and optionally a server key
Add players to the whitelist (see commands below)

Client

Players need the same mod jar in their mods/ folder. On first join to a server with a key configured, a prompt will appear to enter the key. The key is saved automatically and reused on future joins.

Configuration

config/LoginDaddy/logindaddy.properties is generated on first launch.

# sqlite (local file) or mysql
database.type=sqlite

# MySQL only — ignored if using sqlite
mysql.host=localhost
mysql.port=3306
mysql.database=logindaddy
mysql.username=root
mysql.password=

# Optional server key — leave empty to disable
# Players will be prompted to enter this key on first join
server.key=

⚠️ Never share your logindaddy.properties file with anyone.
It contains your database credentials and server key.

Data Files

All mod data is stored under config/LoginDaddy/:

File	Description
`logindaddy.properties`	Server configuration
`logindaddy.db`	SQLite database (only if using SQLite)
`sessions.json`	Active login sessions (server-side)

Client-side data is stored under the client's config/LoginDaddy/:

File	Description
`serverlist.json`	Saved server keys per server address

Commands

Admin commands require operator permission or the server console.

Command	Description
`logindaddy whitelist add <username>`	Add a player to the whitelist
`logindaddy whitelist remove <username>`	Remove a player from the whitelist
`logindaddy whitelist list`	List all whitelisted players
`resetpassword <username> <newpassword>`	Reset a player's password

Player commands (in-game, only usable during authentication):

Command	Description
`/register <password>`	Register with a password (first time only)
`/login <password>`	Log in with your password
`/changepassword <old> <new>`	Change your password (must be logged in)

License

MIT