USBNET

Overview

USBNET is a lightweight helper utility for managing the USB network interface on Lichee-Jack, typically exposed as usb0 when using USB gadget network modes such as DEBUG or NCM.

It provides a minimal, script-friendly way to:

Assign or remove IP addresses
Bring the USB network interface up or down
Prepare a predictable USB networking environment for payloads, debugging, and SFTP management

This tool intentionally avoids NetworkManager and operates directly via iproute2, making it reliable in early boot stages and constrained payload environments.

Typical Use Cases

Configure a static IP for USB CDC-NCM debug mode
Reset USB network state before or after payload execution
Pair with USBMODE DEBUG or USBMODE NCM
Provide a stable management channel (SFTP / SSH) over USB

Supported Actions

Action	Description
`SETIP <ip/mask>`	Assign a static IP address to the USB interface
`NOIP`	Remove all IP addresses from the interface
`IFUP`	Bring the interface up
`IFDOWN`	Bring the interface down

Default interface: usb0 (can be adjusted in the script if needed)

Usage


USBNET SETIP 10.42.0.1/24
USBNET IFUP

Remove IP configuration:


USBNET NOIP

Disable the interface:


USBNET IFDOWN

Integration with USBMODE

USBNET is typically used together with USBMODE:


USBMODE DEBUG
USBNET SETIP 10.42.0.1/24

This combination enables:

USB-powered debug networking
SFTP-based payload and loot management
A safer alternative to USB Mass Storage (UMS)

Design Notes

Uses ip addr and ip link directly (no NetworkManager dependency)
Flushes existing IPs before assignment to avoid conflicts
Logs all actions via logger under the LicheeJack tag
Safe to call repeatedly (idempotent behavior where possible)

USBMODE – controls USB gadget configuration
UDISKCTL – manages loop-mounted disk images for UMS
NETMODE – manages Ethernet-side network behavior
RUN – dispatches payload execution

Summary

USBNET is a small but critical building block in the Lichee-Jack toolchain, providing deterministic USB network control without heavy dependencies. It complements USBMODE and enables a modern, reliable management plane over USB.