Fingerprint library, dbus interface, CLI, and PAM module for unlocking Linux with fingerprint sensors. Currently for Chromebooks. - ChocolateLoverRaj/rust-fp
An already working reimplementation of libfprint in Rust, supposedly easier to use.
Targeted to Chromebooks currently, support wished!
So you use the phones login method and then what? An app uses this and sends a message or key or whatever to the Laptop? Over bluetooth? Or USB? Or Wifi?
That honestly sounds like a lot of struggles, but could work.