This idea is interesting to me because hell making my own stuff is fun. I have access to quite a few usb keys already so technically I might have the material available. Also my threat model is pretty low so I’m interested in security mostly for fun.
Most methods I have found talk about making a key to secure a computer but I would really like to make something that would do WebAuthn.
There is a neat Git project that shows how to turn a few specific devices into 2FA code prompters/automatic fillers. But in my naive mind that falls short of what I would truly wish to be able to accomplish ie. Stock USB --> WebAuthn/Passkey device.
Has anybody seen anything on the subject?
By “USB keys” and “stock USB,” are you talking about USB flash drives? Chances are there’s no way to reprogram the controller in one to act as a HID device rather than mass storage.
I’ll look into HID devices but buying stuff is annoying. I was really hoping to be able to just repurpose a flash drive.
You could try USB Raptor - it’s Windows only and works as a wrapper to use your drive as the authentication since you need special hardware to make an actual HID authentication device as @SpaceNoodle correctly stated.
https://sourceforge.net/projects/usbraptor/
There were a few different resources talking about ways to make a security key that locks/unlocks a computer. It’s not on my radar right now. Thank you for sharing this one.