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Authen::U2F::Tester - FIDO/U2F Authentication Test Client


version 0.03


 my $tester = Authen::U2F::Tester->new(
     cert_file => $certfile,
     key_file  => $keyfile);

 # Test a U2F registration
 my $app_id = '';
 my $challenge = Authen::U2F->challenge;

 my $r = $tester->register($app_id, $challenge);

 unless ($r->is_success) {
     die $r->error_message;

 print $res->client_data;
 print $res->registration_data;

 # the fields in $res can be used to verify the registration using
 # Authen::U2F
 my ($handle, $key) = Authen::U2F->registration_verify(
     challenge         => $challenge,
     app_id            => $app_id,
     origin            => $origin,
     registration_data => $res->registration_data,
     client_data       => $res->client_data);

 # Test a U2F Signing request
 $r = $tester->sign($app_id, $challenge, $handle);

 unless ($r->is_success) {
     die $r->error_message;

 print $res->client_data;
 print $res->signature_data;

 # verify the signing request with Authen::U2F
     challenge      => $challenge,
     app_id         => $app_id,
     origin         => $app_id,
     key_handle     => $handle,
     key            => $key,
     signature_data => $r->signature_data,
     client_data    => $r->client_data);


This module implements a FIDO/U2F tester that can be used for testing web applications that support FIDO/U2F. Think of this module as a "virtual" U2F security key.




The following arguments are required:

  • key_file

    The location of the private key file.

  • cert_file

    The location of the X.509 certificate file.

Alternatively, the key and certificate can be passed in directly as objects:

In order to create and use the tester, you will need both an Elliptic Curve key, and a SSL X.509 certificate. The key can be generated using OpenSSL:

 % openssl ecparam -name secp256r1 -genkey -noout -out key.pem

Then this key can be used to generate a self signed X.509 certificate:

 % openssl req -key key.pem -x509 -days 3560 -sha256 \
     -subj '/C=US/ST=Texas/O=Untrusted U2F Org/CN=virtual-u2f' \
     -out cert.pem

Note that this key is also used to encrypt key handles that the tester generates for registration requests.

key(): Crypt::PK::ECC

Get the key for this tester.

keystore(): Authen::U2F::Tester::Role::Keystore

This returns the key store instance that the tester uses. The default key store is a "wrapped" key store as described in the FIDO/U2F specs. What this means is it does not actually store anything, but instead encrypts the private key using the tester's private key, and returns that as the key handle. This key store will accept any encrypted private key as a valid key handle so long as it can be decrypted by the tester's private key. This is similar to how many physical U2F devices work in the real world. See Authen::U2F::Tester::Keystore::Wrapped for more information.

certificate(): Crypt::OpenSSL::X509

Get the SSL certificate that this tester uses.

register($app_id, $challenge, @keyhandles): Authen::U2F::Tester::RegisterResponse

Complete a registration request.

Returns a Authen::U2F::Tester::RegisterResponse on success, or an Authen::U2F::Error object on failure.

Arguments are:

  • app_id: string

    The application id

  • challenge: string

    The challenge parameter, in Base64 URL encoded format

  • keyhandles: list (optional)

    List of already registered keyhandles for the current user, in Base64 URL format.


 my $app_id = '';
 my $challenge = Authen::U2F->challenge;

 my $res = $tester->register($app_id, $challenge);

 unless ($res->is_success) {
     die $res->error_message;

sign($app_id, $challenge, @keyhandles)

Complete a U2F signing request. Returns a Authen::U2F::Tester::SignResponse object on success, Authen::U2F::Error object otherwise.

Arguments are:

  • app_id

    The appId value

  • challenge

    The challenge parameter, in Base64 URL encoded format

  • keyhandles

    List of possible keyhandles, in Base64 URL encoded format


 my $app_id = '';
 my $challenge = Authen::U2F->challenge;

 my $res = $tester->sign($app_id, $challenge, $keyhandle);

 unless ($res->is_success) {
     die $res->error_message;

 # signature and client data, which should be sent to relaying party for
 # verification.
 print $res->signature_data;
 print $res->client_data;


The development version is on github at http:// and may be cloned from git://


Please report any bugs or feature requests on the bugtracker website

When submitting a bug or request, please include a test-file or a patch to an existing test-file that illustrates the bug or desired feature.


Michael Schout <>


This software is copyright (c) 2017 by Michael Schout.

This is free software; you can redistribute it and/or modify it under the same terms as the Perl 5 programming language system itself.