libfido2: A C repository from Yubico

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

.NET: Fido2Net
Go: go-libfido2
Perl: p5-FIDO-Raw
Rust: libfido2

Releases

The current release of libfido2 is 1.15.0. 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 34 and later

$ sudo dnf install libfido2 libfido2-devel fido2-tools

Ubuntu 20.04 (Focal) and later

$ 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/.

Yubico/libfido2