GEANT/CAT

<?php
/*
 * *****************************************************************************
 * Contributions to this work were made on behalf of the GÉANT project, a 
 * project that has received funding from the European Union’s Framework 
 * Programme 7 under Grant Agreements No. 238875 (GN3) and No. 605243 (GN3plus),
 * Horizon 2020 research and innovation programme under Grant Agreements No. 
 * 691567 (GN4-1) and No. 731122 (GN4-2).
 * On behalf of the aforementioned projects, GEANT Association is the sole owner
 * of the copyright in all material which was developed by a member of the GÉANT
 * project. GÉANT Vereniging (Association) is registered with the Chamber of 
 * Commerce in Amsterdam with registration number 40535155 and operates in the 
 * UK as a branch of GÉANT Vereniging.
 * 
 * Registered office: Hoekenrode 3, 1102BR Amsterdam, The Netherlands. 
 * UK branch address: City House, 126-130 Hills Road, Cambridge CB2 1PQ, UK
 *
 * License: see the web/copyright.inc.php file in the file structure or
 *          <base_url>/copyright.php after deploying the software
 */

$config = array(
    "digest_alg" => "sha512",
    "private_key_type" => OPENSSL_KEYTYPE_EC,
);
   
// Create the private and public key
$res = openssl_pkey_new($config);

// Extract the private key from $res to $privKey
openssl_pkey_export($res, $privKey);

// Extract the public key from $res to $pubKey
$pubKey = openssl_pkey_get_details($res);
$pubKey = $pubKey["key"];

$data = 'plaintext data goes here';

// Encrypt the data to $encrypted using the public key
openssl_public_encrypt($data, $encrypted, $pubKey);

// Decrypt the data using the private key and store the results in $decrypted
openssl_private_decrypt($encrypted, $decrypted, $privKey);

echo $decrypted;