EzLogin

A powerful authentication mod for NeoForge 1.21.1

What is ezLogin?

ezLogin is a lightweight but feature-complete authentication mod for offline-mode and private NeoForge servers. It forces players to register and log in before they can interact with the world — protecting accounts from being hijacked simply by knowing someone's username.

It is server-side only — clients do not need to install it, but it is safe to include in modpacks.

✅ Features

Commands

• /register [password] [confirmPassword] — Create a new account. Automatically logs you in on success.
• /login [password] — Authenticate after joining the server.
• /logout — Manually end your session.
• /changepassword [old] [new] [confirm] — Change your password while logged in.

Protection while unauthenticated

• Blindness — Players are blinded until they log in, preventing them from seeing the world.
• Movement lock — Players cannot move or explore before authenticating.
• Item drop protection — Players cannot drop items. Any attempted drop is silently returned to their inventory with full data preserved — works with modded items, NBT, enchantments, everything.
• Chat blocked — Players cannot send chat messages until logged in.
• Command blocked — All commands except /login and /register are blocked until authenticated.

Security

• Constant-time comparison to prevent timing side-channel attacks.
• Max login attempts — players are kicked after too many failed attempts.
• Login timeout — players are kicked if they don't authenticate within a configurable time window.
• Session timeout — idle sessions can be automatically expired.
• IP auto-login — optionally auto-authenticate returning players from the same IP address.

Offline server support

• Suppresses the vanilla "You logged in from another location" disconnect message that offline servers incorrectly send when a player reconnects.

Admin commands (OP level 2 required)

• /ezlogin setpassword [player] [newPassword] — Force-reset a player's password.
• /ezlogin unregister [player] — Delete a player's account entirely.
• /ezlogin forcelogin [player] — Force-authenticate a player.
• /ezlogin forcelogout [player] — Force-deauthenticate a player.
• /ezlogin info [player] — View registration date, last login, IP, and login count.
• /ezlogin stats — View total registered players and current auth status of online players.

⚙️ Configuration

The config file is generated at:
config/ezlogin/ezlogin-server.toml on first launch.

Configurable options include:

• Minimum and maximum password length
• Login timeout before kick
• Max failed login attempts before kick
• Session idle timeout
• Toggle blindness, movement lock, chat block, command block individually
• IP-based auto-login with configurable validity window

🔧 Requirements

• Minecraft 1.21.1
• NeoForge 21.1.227 or higher
• Java 21
• No client-side installation required

📋 Compatibility

• Designed for offline-mode servers and private LAN/hosted servers
• Works alongside other mods — item drop protection fully preserves modded item NBT data
• Safe to include in modpacks (client install is optional)