firefly-iii/app/Helpers/Webhook/Sha3SignatureGenerator.php
2024-01-01 14:43:56 +01:00

80 lines
2.8 KiB
PHP

<?php
/*
* Sha3SignatureGenerator.php
* Copyright (c) 2021 james@firefly-iii.org
*
* This file is part of Firefly III (https://github.com/firefly-iii).
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU Affero General Public License as
* published by the Free Software Foundation, either version 3 of the
* License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU Affero General Public License for more details.
*
* You should have received a copy of the GNU Affero General Public License
* along with this program. If not, see <https://www.gnu.org/licenses/>.
*/
declare(strict_types=1);
namespace FireflyIII\Helpers\Webhook;
use FireflyIII\Exceptions\FireflyException;
use FireflyIII\Models\WebhookMessage;
/**
* Class Sha3SignatureGenerator
*/
class Sha3SignatureGenerator implements SignatureGeneratorInterface
{
private int $version = 1;
/**
* @throws FireflyException
*/
public function generate(WebhookMessage $message): string
{
// webhook is deleted
if (null === $message->webhook) {
throw new FireflyException('Part of a deleted webhook.');
}
$json = '';
try {
$json = json_encode($message->message, JSON_THROW_ON_ERROR);
} catch (\JsonException $e) {
app('log')->error('Could not generate hash.');
app('log')->error(sprintf('JSON value: %s', $json));
app('log')->error($e->getMessage());
app('log')->error($e->getTraceAsString());
throw new FireflyException('Could not generate JSON for SHA3 hash.', 0, $e);
}
// signature v1 is generated using the following structure:
// The signed_payload string is created by concatenating:
// The timestamp (as a string)
// The character .
// The character .
// The actual JSON payload (i.e., the request body)
$timestamp = time();
$payload = sprintf('%s.%s', $timestamp, $json);
$signature = hash_hmac('sha3-256', $payload, $message->webhook->secret, false);
// signature string:
// header included in each signed event contains a timestamp and one or more signatures.
// The timestamp is prefixed by t=, and each signature is prefixed by a scheme.
// Schemes start with v, followed by an integer. Currently, the only valid live signature scheme is v1.
return sprintf('t=%s,v%d=%s', $timestamp, $this->getVersion(), $signature);
}
public function getVersion(): int
{
return $this->version;
}
}