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Editing: Throttler.php
<?php declare(strict_types=1); /** * SPDX-FileCopyrightText: 2016 Nextcloud GmbH and Nextcloud contributors * SPDX-License-Identifier: AGPL-3.0-or-later */ namespace OC\Security\Bruteforce; use OC\Security\Bruteforce\Backend\IBackend; use OC\Security\Ip\BruteforceAllowList; use OC\Security\Normalizer\IpAddress; use OCP\AppFramework\Utility\ITimeFactory; use OCP\IConfig; use OCP\Security\Bruteforce\IThrottler; use OCP\Security\Bruteforce\MaxDelayReached; use Psr\Log\LoggerInterface; /** * Class Throttler implements the bruteforce protection for security actions in * Nextcloud. * * It is working by logging invalid login attempts to the database and slowing * down all login attempts from the same subnet. The max delay is 30 seconds and * the starting delay are 200 milliseconds. (after the first failed login) * * This is based on Paragonie's AirBrake for Airship CMS. You can find the original * code at https://github.com/paragonie/airship/blob/7e5bad7e3c0fbbf324c11f963fd1f80e59762606/src/Engine/Security/AirBrake.php * * @package OC\Security\Bruteforce */ class Throttler implements IThrottler { /** @var bool[] */ private array $hasAttemptsDeleted = []; public function __construct( private ITimeFactory $timeFactory, private LoggerInterface $logger, private IConfig $config, private IBackend $backend, private BruteforceAllowList $allowList, ) { } /** * {@inheritDoc} */ public function registerAttempt(string $action, string $ip, array $metadata = []): void { // No need to log if the bruteforce protection is disabled if (!$this->config->getSystemValueBool('auth.bruteforce.protection.enabled', true)) { return; } $ipAddress = new IpAddress($ip); if ($this->isBypassListed((string)$ipAddress)) { return; } $this->logger->notice( sprintf( 'Bruteforce attempt from "%s" detected for action "%s".', $ip, $action ), [ 'app' => 'core', ] ); $this->backend->registerAttempt( (string)$ipAddress, $ipAddress->getSubnet(), $this->timeFactory->getTime(), $action, $metadata ); } /** * Check if the IP is whitelisted */ public function isBypassListed(string $ip): bool { return $this->allowList->isBypassListed($ip); } /** * {@inheritDoc} */ public function showBruteforceWarning(string $ip, string $action = ''): bool { $attempts = $this->getAttempts($ip, $action); // 4 failed attempts is the last delay below 5 seconds return $attempts >= 4; } /** * {@inheritDoc} */ public function getAttempts(string $ip, string $action = '', float $maxAgeHours = 12): int { if ($maxAgeHours > 48) { $this->logger->error('Bruteforce has to use less than 48 hours'); $maxAgeHours = 48; } if ($ip === '' || isset($this->hasAttemptsDeleted[$action])) { return 0; } $ipAddress = new IpAddress($ip); if ($this->isBypassListed((string)$ipAddress)) { return 0; } $maxAgeTimestamp = (int)($this->timeFactory->getTime() - 3600 * $maxAgeHours); return $this->backend->getAttempts( $ipAddress->getSubnet(), $maxAgeTimestamp, $action !== '' ? $action : null, ); } /** * {@inheritDoc} */ public function getDelay(string $ip, string $action = ''): int { $attempts = $this->getAttempts($ip, $action); return $this->calculateDelay($attempts); } /** * {@inheritDoc} */ public function calculateDelay(int $attempts): int { if ($attempts === 0) { return 0; } $firstDelay = 0.1; if ($attempts > $this->config->getSystemValueInt('auth.bruteforce.max-attempts', self::MAX_ATTEMPTS)) { // Don't ever overflow. Just assume the maxDelay time:s return self::MAX_DELAY_MS; } $delay = $firstDelay * 2 ** $attempts; if ($delay > self::MAX_DELAY) { return self::MAX_DELAY_MS; } return (int)\ceil($delay * 1000); } /** * {@inheritDoc} */ public function resetDelay(string $ip, string $action, array $metadata): void { // No need to log if the bruteforce protection is disabled if (!$this->config->getSystemValueBool('auth.bruteforce.protection.enabled', true)) { return; } $ipAddress = new IpAddress($ip); if ($this->isBypassListed((string)$ipAddress)) { return; } $this->backend->resetAttempts( $ipAddress->getSubnet(), $action, $metadata, ); $this->hasAttemptsDeleted[$action] = true; } /** * {@inheritDoc} */ public function resetDelayForIP(string $ip): void { // No need to log if the bruteforce protection is disabled if (!$this->config->getSystemValueBool('auth.bruteforce.protection.enabled', true)) { return; } $ipAddress = new IpAddress($ip); if ($this->isBypassListed((string)$ipAddress)) { return; } $this->backend->resetAttempts($ipAddress->getSubnet()); } /** * {@inheritDoc} */ public function sleepDelay(string $ip, string $action = ''): int { $delay = $this->getDelay($ip, $action); if (!$this->config->getSystemValueBool('auth.bruteforce.protection.testing')) { usleep($delay * 1000); } return $delay; } /** * {@inheritDoc} */ public function sleepDelayOrThrowOnMax(string $ip, string $action = ''): int { $maxAttempts = $this->config->getSystemValueInt('auth.bruteforce.max-attempts', self::MAX_ATTEMPTS); $attempts = $this->getAttempts($ip, $action); if ($attempts > $maxAttempts) { $attempts30mins = $this->getAttempts($ip, $action, 0.5); if ($attempts30mins > $maxAttempts) { $this->logger->info('IP address blocked because it reached the maximum failed attempts in the last 30 minutes [action: {action}, attempts: {attempts}, ip: {ip}]', [ 'action' => $action, 'ip' => $ip, 'attempts' => $attempts30mins, ]); // If the ip made too many attempts within the last 30 mins we don't execute anymore throw new MaxDelayReached('Reached maximum delay'); } $this->logger->info('IP address throttled because it reached the attempts limit in the last 12 hours [action: {action}, attempts: {attempts}, ip: {ip}]', [ 'action' => $action, 'ip' => $ip, 'attempts' => $attempts, ]); } if ($attempts > 0) { return $this->calculateDelay($attempts); } return 0; } }
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