fprintd

Manage fingerprint authentication devices

TLDR

Display the man page for fprintd

$ man fprintd

fprintd is a daemon that provides a standardized interface for applications to access fingerprint readers. It allows users to authenticate using their fingerprints instead of passwords for various tasks, such as logging in, unlocking the screen, or gaining administrative privileges. fprintd handles the communication with the fingerprint reader hardware, enrollment of fingerprints, and matching of fingerprint scans against enrolled fingerprints.

It operates as a system service and requires appropriate permissions to access hardware. User enrollment and verification processes are typically handled through graphical interfaces (e.g., GNOME Settings) or command-line tools that interact with the fprintd daemon. The core daemon itself doesn't directly interact with the user but rather provides an API (typically via D-Bus) for other applications to utilize fingerprint authentication.

CAVEATS

fprintd relies on device drivers and libraries (libfprint) to support specific fingerprint readers. Not all fingerprint readers are supported, and compatibility can vary. Enrollment and verification performance can also depend on the quality of the fingerprint reader and the condition of the user's fingers.

D-BUS API

Applications communicate with fprintd through a D-Bus API. This API allows applications to enroll fingerprints, verify fingerprints, and manage fingerprint reader devices.

PAM INTEGRATION

fprintd integrates with the Pluggable Authentication Modules (PAM) framework through pam_fprintd, allowing fingerprint authentication to be used for system login and other PAM-enabled services.

HISTORY

fprintd was created to provide a consistent and secure method for fingerprint authentication across different desktop environments and applications on Linux systems. Before fprintd, fingerprint reader support was often fragmented and inconsistent. fprintd aimed to address this by providing a centralized service. The project was initially developed in the mid-2000s and has been actively maintained.