pam_u2f - is an important library because it supports many inexpensive u2f keys available from different manufacturers. You can log in as a user or log in via ssh, for example.
Luckily it works fine on FreeBSD 13.0 (pam_u2f-1.2.0, u2f-devd-1.1.10_6, libfido2-1.8.0).
Here is the Makefile...
