<?php
declare(strict_types=1);
/*
* The MIT License (MIT)
*
* Copyright (c) 2014-2021 Spomky-Labs
*
* This software may be modified and distributed under the terms
* of the MIT license. See the LICENSE file for details.
*/
namespace Cose\Algorithm\Signature\EdDSA;
use Assert\Assertion;
use Cose\Algorithm\Signature\Signature;
use Cose\Algorithms;
use Cose\Key\Key;
use Cose\Key\OkpKey;
use InvalidArgumentException;
use function sodium_crypto_sign_detached;
use function sodium_crypto_sign_verify_detached;
class EdDSA implements Signature
{
public function sign(string $data, Key $key): string
{
$key = $this->handleKey($key);
Assertion::true($key->isPrivate(), 'The key is not private');
$x = $key->x();
$d = $key->d();
$secret = $d.$x;
switch ($key->curve()) {
case OkpKey::CURVE_ED25519:
return sodium_crypto_sign_detached($data, $secret);
default:
throw new InvalidArgumentException('Unsupported curve');
}
}
public function verify(string $data, Key $key, string $signature): bool
{
$key = $this->handleKey($key);
switch ($key->curve()) {
case OkpKey::CURVE_ED25519:
return sodium_crypto_sign_verify_detached($signature, $data, $key->x());
default:
throw new InvalidArgumentException('Unsupported curve');
}
}
public static function identifier(): int
{
return Algorithms::COSE_ALGORITHM_EdDSA;
}
private function handleKey(Key $key): OkpKey
{
return new OkpKey($key->getData());
}
}