Ugreen NAS Docker MCP Server Setup

This repository contains a secure, containerized Model Context Protocol (MCP) server designed to be hosted on your Ugreen NAS (UGOS).

Security Architecture (Pre-Gateway Mitigations)

This setup is configured with several key pre-gateway security practices:

1. Transport Layer Token Authentication: Direct SSE access is protected with a token (X-API-Key header).

2. Container Isolation (Non-Root): The server runs as mcpuser (UID/GID 1000) inside the container. Even if a tool is compromised, the attacker has no root privileges and is restricted to the container environment.

3. Directory Sandboxing: The list_nas_shared_directories tool is restricted to /volume1/shared inside the container. It cannot traverse to other system files or directories on your NAS.

4. Environment-Driven Secrets: The secret token is passed via a Docker environment variable rather than hardcoded in the codebase.

Related MCP server: mcp-s3-server

Deployment on Ugreen NAS (UGOS)

Step 1: Build the Docker Image

You can build this image locally and push it to your NAS, or build it directly on the NAS if you have SSH enabled:

docker build -t ugreen-nas-mcp:latest .

Step 2: Running via Ugreen Container Manager UI

1. Open the App Center -> Container Manager (or Docker app) on your Ugreen NAS.

2. Go to Image and import/load ugreen-nas-mcp:latest or upload the folder and build it.

3. Create a new container with the image:

   • Network: Bridge (recommended, expose port 8000).

   • Port Settings: Map Container Port 8000 to Host Port 8000 (or another free port like 8080).

   • Environment Variables:

     • MCP_SECRET_TOKEN: Set a strong random password (e.g. uGr33n-S3cur3-Mcp-2026!).

   • Volume/Bind Mounts:

     • Mount the NAS shared directory you want the MCP to access (e.g. /volume1/homes or a specific shared folder /volume1/Public) to /volume1/shared inside the container. Set it to Read-Only (Recommended) for maximum security.

4. Start the container.

Client Configuration

To connect your AI client (e.g., Claude Desktop, Cursor, or another MCP client) to the NAS MCP server, update your client's configuration file:

Example: claude_desktop_config.json

Replace <NAS_IP> with the local IP address of your Ugreen NAS, and the header value with your configured MCP_SECRET_TOKEN.

{
  "mcpServers": {
    "ugreen-nas-mcp": {
      "type": "sse",
      "url": "http://<NAS_IP>:8000/mcp/sse",
      "headers": {
        "X-API-Key": "your-configured-mcp-secret-token"
      }
    }
  }
}

Verification & Testing

To verify the server is running and secure, run a quick curl command from your computer:

# Verify it blocks unauthorized access (Should return 401 Unauthorized)
curl -i http://<NAS_IP>:8000/mcp/sse

# Verify authorized access (Should establish connection)
curl -i -H "X-API-Key: your-configured-mcp-secret-token" http://<NAS_IP>:8000/mcp/sse