> ## Documentation Index
> Fetch the complete documentation index at: https://docs.xreatlabs.space/llms.txt
> Use this file to discover all available pages before exploring further.

# Premium Authentication

> Automatic premium account authentication with Minecraft's official authentication system

# Premium Authentication

NexAuth provides seamless integration with Minecraft's premium authentication system, allowing legitimate Minecraft account holders to authenticate automatically without passwords.

## Overview

Premium authentication leverages Mojang's official authentication servers to verify player identities automatically, providing a secure and convenient login experience for players who own Minecraft.

<Features>
  <Feature icon="zap" title="Automatic Login" description="Premium players join without entering passwords - verification happens automatically." />

  <Feature icon="shield" title="Secure Verification" description="Uses Mojang's official authentication system for account verification." />

  <Feature icon="users" title="Mixed Mode" description="Support both premium and cracked players on the same server." />
</Features>

## Configuration

### Basic Setup

```hocon theme={null}
# Should we automatically register all players with a premium nickname?
# !!CRACKED PLAYERS WILL NOT BE ABLE TO REGISTER PREMIUM USERNAMES!!
auto-register=false

# Sets the strategy for resolving profile conflicts. Available strategies:
# BLOCK - Kick both players with the message key "kick-name-mismatch"
# USE_OFFLINE - Use the offline profile
# OVERWRITE - Overwrite the offline profile's data
profile-conflict-resolution-strategy=BLOCK

# The default crypto provider. This is used for hashing passwords. Available Providers:
# BCrypt-2A - Newer, more safe, recommended
# Argon-2ID - Newest, should be safer than BCrypt-2A, however, it can slow down the server
# SHA-256 - Older, not recommended. Kept for compatibility reasons
# SHA-512 - More safer than SHA-256, but still not recommended
default-crypto-provider=BCrypt-2A
```

## Commands

* `/premium <password>` - Enable premium auto-login
* `/premiumconfirm` - Confirm premium linking
* `/cracked` - Disable premium auto-login
* `/premium status` - Check premium status
* `/premium link <username>` - Link accounts (admin)
* `/premium skin refresh` - Update player skin

## Configuration Options

### `auto-register: true/false`

Automatically register all players with premium Minecraft usernames.

* **true**: Premium players are auto-registered and can join without passwords
* **false**: Premium players must use `/premium <password>` to enable auto-login

**Note:** When enabled, cracked players cannot register premium usernames.

### `profile-conflict-resolution-strategy: BLOCK|USE_OFFLINE|OVERWRITE`

Defines how to handle conflicts when a premium player joins with a username that already exists as an offline account.

* **BLOCK** (default): Kick both players with an error message. Admin must resolve manually.
* **USE\_OFFLINE**: Use the offline profile. Both players must login with the offline password.
* **OVERWRITE**: Delete offline data and use premium profile. ⚠️ Use with caution - can be abused!

### `default-crypto-provider: BCrypt-2A`

The default encryption method for password hashing.

Available providers:

* **BCrypt-2A** (recommended): Modern, secure hashing
* **Argon-2ID**: Newest, most secure but slower
* **SHA-256**: Legacy, not recommended
* **SHA-512**: Legacy, not recommended

## Next Steps

<Card title="Offline Mode" icon="user" href="/nexauth/features/offline">
  Configure offline player authentication.
</Card>