libfido2

libfido2 provides library functionality and command-line tools to communicate with a FIDO device over USB or NFC, and to verify attestation and assertion signatures.

libfido2 supports the FIDO U2F (CTAP 1) and FIDO2 (CTAP 2) protocols.

For usage, see the examples/ directory.

License

libfido2 is licensed under the BSD 2-clause license. See the LICENSE file for the full license text.

Supported Platforms

libfido2 is known to work on Linux, macOS, Windows, OpenBSD, and FreeBSD.

Documentation

Documentation is available in troff and HTML formats. An online mirror of libfido2's documentation is also available.

Bindings

Releases

The current release of libfido2 is 1.14.0. Signed release tarballs are available at Yubico’s release page.

Dependencies

libfido2 depends on libcbor, OpenSSL 1.1 or newer, and zlib. On Linux, libudev (part of systemd) is also required.

Installation

Fedora 35 and 34

sudo dnf install libfido2 libfido2-devel fido2-tools

Ubuntu 22.04 (Jammy) and 20.04 (Focal)

sudo apt install libfido2-1 libfido2-dev libfido2-doc fido2-tools

Alternatively, newer versions of libfido2 are available in Yubico’s PPA. Follow the instructions for Ubuntu 18.04 (Bionic) below.

Ubuntu 18.04 (Bionic)

sudo apt install software-properties-common
sudo apt-add-repository ppa:yubico/stable
sudo apt update
sudo apt install libfido2-1 libfido2-dev libfido2-doc fido2-tools

On Linux, you may need to add a udev rule to be able to access the FIDO device. For example, the udev rule may contain the following:

#udev rule for allowing HID access to Yubico devices for FIDO support.

KERNEL=="hidraw*", SUBSYSTEM=="hidraw", \
  MODE="0664", GROUP="plugdev", ATTRS{idVendor}=="1050"

macOS

brew install libfido2

Windows

Please consult Yubico’s release page for ARM, ARM64, Win32, and Win64 artefacts.

Building from source

On UNIX-like systems:

cmake -B build
make -C build
sudo make -C build install

Depending on the platform, pkg-config may need to be installed, or the PKG_CONFIG_PATH environment variable set. For complete, OS-specific build instructions, please refer to the .actions/ (Linux, macOS, BSD) and windows/ directories.

Build-time Customisation

libfido2 supports a number of CMake options. Some of the options require additional dependencies. Options that are disabled by default are not officially supported.

Option

Description

Default

BUILD_EXAMPLES

Build example programs

ON

BUILD_MANPAGES

Build man pages

ON

BUILD_SHARED_LIBS

Build a shared library

ON

BUILD_STATIC_LIBS

Build a static library

ON

BUILD_TOOLS

Build auxiliary tools

ON

FUZZ

Enable fuzzing instrumentation

OFF

NFC_LINUX

Enable netlink NFC support on Linux

ON

USE_HIDAPI

Use hidapi as the HID backend

OFF

USE_PCSC

Enable experimental PCSC support

OFF

USE_WINHELLO

Abstract Windows Hello as a FIDO device

ON

The USE_HIDAPI option requires hidapi. The USE_PCSC option requires pcsc-lite on Linux.

Development

Please use GitHub Discussions to ask questions and suggest features, and GitHub pull-requests for code contributions.

Reporting bugs

Please use GitHub Issues to report bugs. To report security issues, please contact security@yubico.com. A PGP public key can be found at https://www.yubico.com/support/security-advisories/issue-rating-system/.