A script to encrypt two-factor authenticator secrets for Feide

encrypt.php

<?php
include("vendor/autoload.php");

// JSON-encode the Authenticator secret
$plaintext = array("secret" => "<AUTHENTICATOR_SECRET");

// initialize JWE object
$jwe = new JOSE_JWE(json_encode($plaintext));

// encrypt with Feide's key and proper algorithms
$jwe->encrypt(
    '<FEIDE_AUTHENTICATOR_PUBLIC_KEY>',
    'RSA-OAEP',
    'A128CBC-HS256'
);

// print the result
echo $jwe->toString();