Mobile Companion
Multi-device collaboration via QR codes, mobile photo capture, and real-time synchronization for hardware testing.
Overview
The Mobile Companion is Gauntlet's multi-device collaboration feature. Hardware security testing often requires the tester to be physically at the device while simultaneously managing the software assessment on a separate machine. The companion allows a phone or tablet to join a Gauntlet session for photo capture and status monitoring.
How to Join
Three methods to connect a mobile device to a Gauntlet project:
https://<testing-machine-ip>:<port>/join/<project_id> in the mobile browser. The port defaults to 5600. Accept the self-signed certificate warning.Join Page
The join page (/join/<project_id>) is a mobile-optimized view that shows:
- Project name and device under test
- All interfaces configured in the project
- Camera capture button for the currently requested photo module
- Upload status and confirmation
The join page uses SocketIO to stay synchronized with the main Gauntlet session. When the tester triggers a new photo module on the desktop, the companion page automatically updates to show which photo is needed next.
Photo Capture Flow
- Gearbox reaches a photo module (e.g., "Photo" for Ethernet eth0)
- A
__GB_PROMPT__token arrives at Gauntlet with the photo context (sub-device, interface, instance, module) - Gauntlet stores the photo context and renders a QR/prompt on the Testing tab
- The companion device (already joined or newly scanning the QR) sees the camera view for that specific module
- The tester takes the photo on the mobile device
- The photo uploads via
POST /upload_photowith the project ID and instance context - Gauntlet saves the photo to the correct evidence directory and sends the answer back to Gearbox's stdin
- Gearbox proceeds to the next module
Multi-Device Synchronization
All connected devices (desktop browser and any mobile companions) stay synchronized via SocketIO rooms. Events broadcast to the project room include:
| Event | Effect |
|---|---|
gearbox_started | All devices show the active assessment state |
gearbox_output | Console output streams to all connected views |
gearbox_finding | New findings appear on all devices instantly |
photo_uploaded | Photo confirmation appears on both desktop and mobile |
gearbox_stopped | All devices reflect the stopped state |
Network Requirements
The mobile device must be on the same network (or have routing to) the testing machine. Gauntlet runs over HTTPS with a self-signed certificate, so mobile browsers will show a certificate warning on first connection — accept it to proceed. The per-interface QR codes ensure the mobile device gets a URL with an IP address it can actually reach.