Continuously Running Userland Diagnostics Daemon (CRUDD)

CRUDD allows a user to remotely execute a series of "safe" diagnostics tools via a web interface.

CRUDD's number one invariant is that it will only run pre-vetted commands and does not provide arbitrary remote code execution.

This is loosely based on a workstation dianostics daemon used at Google but shares zero code with it.

Running CRUDD

Prerequisites

• Have Go (>=1.21) installed

• (Optional) Have Docker installed

Running directly

$ go run crudd

Access crudd at localhost:4901

Running in Docker

$ docker build -t crudd . && docker run --rm -it -p 4901:4901/tcp crudd

Access crudd at localhost:4901

Installing as a Service

Run install.sh to:

1. Compile crudd
2. Install crudd to /usr/bin/crudd
3. Install crudd.service as a Systemd service
4. Enable and start crudd.service

Access crudd at localhost:4901

Safety

While CRUDD tries to never run commands that may leak sensitive information it is recommended to not expose CRUDD directly to the internet. CRUDD exec's diagnostic commands as subprocesses, so it would be trivial to take advantage of this to cause a thread exhaustion attack.

I personally run CRUDD behind nginx configured with an IP allowlist and primarily access it only from my LAN.

Screenshots