= Examples

=== Definitions

The following definitions are used in the description below:

- <device>

	The file system path or subsystem-specific identification string of a
	FIDO device.

- <pin>, [oldpin]

	Strings passed directly in the executed command's argument vector.

- <cred_id>

	The file system path of a file containing a FIDO credential ID in
	binary representation.

- <pubkey>

	The file system path of a file containing a NIST P-256 public key in
	PEM format.

- <blobkey>

	A credential's associated CTAP 2.1 "largeBlob" symmetric key.

=== Description

The following examples are provided:

- manifest

	Prints a list of configured FIDO devices.

- info <device>

	Prints information about <device>.

- reset <device>

	Performs a factory reset on <device>.

- setpin <pin> [oldpin] <device>

	Configures <pin> as the new PIN of <device>. If [oldpin] is provided,
	the device's PIN is changed from [oldpin] to <pin>.

- cred [-t es256|es384|rs256|eddsa] [-k pubkey] [-ei cred_id] [-P pin]
       [-T seconds] [-b blobkey] [-hruv] <device>

	Creates a new credential on <device> and verify that the credential
	was signed by the authenticator. The device's attestation certificate
	is not verified. If option -k is specified, the credential's public
	key is stored in <pubkey>. If option -i is specified, the credential
	ID is stored in <cred_id>. The -e option may be used to add <cred_id>
	to the list of excluded credentials. If option -h is specified,
	the hmac-secret FIDO2 extension is enabled on the generated
	credential. If option -r is specified, the generated credential
	will involve a resident key. User verification may be requested
	through the -v option. If option -u is specified, the credential
	is generated using U2F (CTAP1) instead of FIDO2 (CTAP2) commands.
	The -T option may be used to enforce a timeout of <seconds>. If the
	option -b is specified, the credential's "largeBlob" key is stored in
	<blobkey>.

- assert [-t es256|es384|rs256|eddsa] [-a cred_id] [-h hmac_secret] [-P pin]
         [-s hmac_salt] [-T seconds] [-b blobkey] [-puv] <pubkey> <device>

	Asks <device> for a FIDO2 assertion corresponding to [cred_id],
	which may be omitted for resident keys. The obtained assertion
	is verified using <pubkey>. The -p option requests that the user
	be present.  User verification may be requested through the -v
	option. If option -u is specified, the assertion is generated using
	U2F (CTAP1) instead of FIDO2 (CTAP2) commands. If option -s is
	specified, a FIDO2 hmac-secret is requested from the authenticator,
	and the contents of <hmac_salt> are used as the salt. If option -h
	is specified, the resulting hmac-secret is stored in <hmac_secret>.
	The -T option may be used to enforce a timeout of <seconds>. If the
	option -b specified, the credential's "largeBlob" key is stored in
	<blobkey>.

- retries <device>
	Get the number of PIN attempts left on <device> before lockout.

- select

	Enumerates available FIDO devices and, if more than one is present,
	simultaneously requests touch on all of them, printing information
	about the device touched.

Debugging is possible through the use of the FIDO_DEBUG environment variable.
If set, libfido2 will produce a log of its transactions with the authenticator.

Additionally, an example of a WebAuthn client using libfido2 is available at
https://github.com/martelletto/fido2-webauthn-client.