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<?php |
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/* |
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* This file is part of the Shieldon package. |
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* |
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* (c) Terry L. <[email protected]> |
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* |
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* For the full copyright and license information, please view the LICENSE |
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* file that was distributed with this source code. |
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*/ |
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declare(strict_types=1); |
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namespace Shieldon\Firewall\Kernel; |
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use Shieldon\Firewall\Kernel; |
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use function Shieldon\Firewall\get_request; |
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use function Shieldon\Firewall\get_session; |
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use function Shieldon\Firewall\unset_superglobal; |
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use function time; |
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/* |
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* This trait is used on Kernel only. |
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*/ |
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trait FilterTrait |
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{ |
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/** |
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* Enable or disable the filters. |
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* |
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* @var array |
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*/ |
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protected $filterStatus = [ |
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/** |
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* Check how many pageviews an user made in a short period time. |
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* For example, limit an user can only view 30 pages in 60 minutes. |
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*/ |
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'frequency' => true, |
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/** |
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* If an user checks any internal link on your website, the user's |
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* browser will generate HTTP_REFERER information. |
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* When a user view many pages without HTTP_REFERER information meaning |
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* that the user MUST be a web crawler. |
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*/ |
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'referer' => false, |
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/** |
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* Most of web crawlers do not render JavaScript, they only get the |
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* content they want, so we can check whether the cookie can be created |
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* by JavaScript or not. |
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*/ |
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'cookie' => false, |
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/** |
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* Every unique user should only has a unique session, but if a user |
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* creates different sessions every connection... meaning that the |
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* user's browser doesn't support cookie. |
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* It is almost impossible that modern browsers not support cookie, |
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* therefore the user MUST be a web crawler. |
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*/ |
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'session' => false, |
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]; |
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/** |
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* The status for Filters to reset. |
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* |
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* @var array |
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*/ |
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protected $filterResetStatus = [ |
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's' => false, // second. |
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'm' => false, // minute. |
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'h' => false, // hour. |
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'd' => false, // day. |
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]; |
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/** |
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* Start an action for this IP address, allow or deny, and give a reason for it. |
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* |
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* @param int $actionCode - 0: deny, 1: allow, 9: unban. |
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* @param string $reasonCode |
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* @param string $assignIp |
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* |
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* @return void |
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*/ |
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abstract function action(int $actionCode, int $reasonCode, string $assignIp = ''): void; |
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/** |
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* Set the filters. |
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* |
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* @param array $settings filter settings. |
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* |
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* @return void |
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*/ |
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public function setFilters(array $settings) |
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{ |
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foreach (array_keys($this->filterStatus) as $k) { |
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if (isset($settings[$k])) { |
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$this->filterStatus[$k] = $settings[$k] ?? false; |
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} |
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} |
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} |
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/** |
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* Set a filter. |
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* |
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* @param string $filterName The filter's name. |
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* @param bool $value True for enabling the filter, overwise. |
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* |
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* @return void |
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*/ |
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public function setFilter(string $filterName, bool $value): void |
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{ |
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if (isset($this->filterStatus[$filterName])) { |
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$this->filterStatus[$filterName] = $value; |
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} |
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} |
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/** |
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* Disable filters. |
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*/ |
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public function disableFilters(): void |
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{ |
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$this->setFilters([ |
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'session' => false, |
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'cookie' => false, |
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'referer' => false, |
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'frequency' => false, |
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]); |
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} |
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/* |
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|-------------------------------------------------------------------------- |
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| Stage in Kernel |
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|-------------------------------------------------------------------------- |
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| The below methods are used in "process" method in Kernel. |
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*/ |
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/** |
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* Detect and analyze an user's behavior. |
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* |
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* @return int The response code. |
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*/ |
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protected function filter(): int |
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{ |
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$now = time(); |
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$isFlagged = false; |
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// Fetch an IP data from Shieldon log table. |
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$ipDetail = $this->driver->get($this->ip, 'filter'); |
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$ipDetail = $this->driver->parseData($ipDetail, 'filter'); |
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$logData = $ipDetail; |
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// Counting user pageviews. |
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foreach (array_keys($this->filterResetStatus) as $unit) { |
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// Each time unit will increase by 1. |
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$logData['pageviews_' . $unit] = $ipDetail['pageviews_' . $unit] + 1; |
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$logData['first_time_' . $unit] = $ipDetail['first_time_' . $unit]; |
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} |
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$logData['first_time_flag'] = $ipDetail['first_time_flag']; |
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if (!empty($ipDetail['ip'])) { |
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$logData['ip'] = $this->ip; |
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$logData['session'] = get_session()->get('id'); |
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$logData['hostname'] = $this->rdns; |
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$logData['last_time'] = $now; |
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// Start checking... |
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foreach (array_keys($this->filterStatus) as $filter) { |
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// For example: filterSession |
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$method = 'filter' . ucfirst($filter); |
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// For example: call $this->filterSession |
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$filterReturnData = $this->{$method}($logData, $ipDetail, $isFlagged); |
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// The log data will be updated by the filter. |
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$logData = $filterReturnData['log_data']; |
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// The flag will be passed to the next Filter. |
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$isFlagged = $filterReturnData['is_flagged']; |
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// If we find this session reached the filter limit, reject it. |
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$isReject = $filterReturnData['is_reject']; |
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if ($isReject) { |
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return kernel::RESPONSE_TEMPORARILY_DENY; |
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} |
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} |
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// Is fagged as unusual beavior? Count the first time. |
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if ($isFlagged) { |
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$logData['first_time_flag'] = (!empty($logData['first_time_flag'])) ? $logData['first_time_flag'] : $now; |
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} |
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// Reset the flagged factor check. |
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if (!empty($ipDetail['first_time_flag'])) { |
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if ($now - $ipDetail['first_time_flag'] >= $this->properties['time_reset_limit']) { |
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$logData['flag_multi_session'] = 0; |
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$logData['flag_empty_referer'] = 0; |
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$logData['flag_js_cookie'] = 0; |
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} |
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} |
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$this->driver->save($this->ip, $logData, 'filter'); |
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} else { |
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// If $ipDetail[ip] is empty. |
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// It means that the user is first time visiting our webiste. |
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$this->InitializeFirstTimeFilter($logData); |
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} |
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return kernel::RESPONSE_ALLOW; |
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} |
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/* |
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|-------------------------------------------------------------------------- |
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| The below methods are used only in "filter" method in current Trait. |
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| See "Start checking..." |
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|-------------------------------------------------------------------------- |
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*/ |
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/** |
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* When the user is first time visiting our webiste. |
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* Initialize the log data. |
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* |
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* @param array $logData The user's log data. |
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* |
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* @return void |
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*/ |
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protected function InitializeFirstTimeFilter($logData) |
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{ |
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$now = time(); |
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$logData['ip'] = $this->ip; |
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$logData['session'] = get_session()->get('id'); |
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$logData['hostname'] = $this->rdns; |
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$logData['last_time'] = $now; |
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foreach (array_keys($this->filterResetStatus) as $unit) { |
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$logData['first_time_' . $unit] = $now; |
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} |
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$this->driver->save($this->ip, $logData, 'filter'); |
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} |
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/** |
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* Filter - Referer. |
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* |
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* @param array $logData IP data from Shieldon log table. |
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* @param array $ipData The IP log data. |
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* @param bool $isFlagged Is flagged as unusual behavior or not. |
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* |
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* @return array |
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*/ |
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protected function filterReferer(array $logData, array $ipDetail, bool $isFlagged): array |
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{ |
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$isReject = false; |
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if ($this->filterStatus['referer']) { |
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if ($logData['last_time'] - $ipDetail['last_time'] > $this->properties['interval_check_referer']) { |
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// Get values from data table. We will count it and save it back to data table. |
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// If an user is already in your website, it is impossible no referer when he views other pages. |
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$logData['flag_empty_referer'] = $ipDetail['flag_empty_referer']; |
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if (empty(get_request()->getHeaderLine('referer'))) { |
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$logData['flag_empty_referer']++; |
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$isFlagged = true; |
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} |
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// Ban this IP if they reached the limit. |
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if ($logData['flag_empty_referer'] > $this->properties['limit_unusual_behavior']['referer']) { |
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$this->action( |
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kernel::ACTION_TEMPORARILY_DENY, |
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kernel::REASON_EMPTY_REFERER |
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); |
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$isReject = true; |
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} |
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} |
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} |
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return [ |
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'is_flagged' => $isFlagged, |
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'is_reject' => $isReject, |
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'log_data' => $logData, |
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]; |
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} |
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/** |
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* Filter - Session |
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* |
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* @param array $logData IP data from Shieldon log table. |
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* @param array $ipData The IP log data. |
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* @param bool $isFlagged Is flagged as unusual behavior or not. |
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* |
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* @return array |
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*/ |
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protected function filterSession(array $logData, array $ipDetail, bool $isFlagged): array |
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{ |
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$isReject = false; |
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if ($this->filterStatus['session']) { |
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if ($logData['last_time'] - $ipDetail['last_time'] > $this->properties['interval_check_session']) { |
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// Get values from data table. We will count it and save it back to data table. |
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$logData['flag_multi_session'] = $ipDetail['flag_multi_session']; |
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if (get_session()->get('id') !== $ipDetail['session']) { |
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// Is is possible because of direct access by the same user many times. |
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// Or they don't have session cookie set. |
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$logData['flag_multi_session']++; |
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$isFlagged = true; |
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} |
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// Ban this IP if they reached the limit. |
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if ($logData['flag_multi_session'] > $this->properties['limit_unusual_behavior']['session']) { |
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$this->action( |
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kernel::ACTION_TEMPORARILY_DENY, |
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kernel::REASON_TOO_MANY_SESSIONS |
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); |
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$isReject = true; |
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} |
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} |
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329
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|
|
} |
|
330
|
|
|
|
|
331
|
|
|
|
|
332
|
|
|
return [ |
|
333
|
|
|
'is_flagged' => $isFlagged, |
|
334
|
|
|
'is_reject' => $isReject, |
|
335
|
|
|
'log_data' => $logData, |
|
336
|
|
|
]; |
|
337
|
|
|
} |
|
338
|
|
|
|
|
339
|
|
|
/** |
|
340
|
|
|
* Filter - Cookie |
|
341
|
|
|
* |
|
342
|
|
|
* @param array $logData IP data from Shieldon log table. |
|
343
|
|
|
* @param array $ipData The IP log data. |
|
344
|
|
|
* @param bool $isFlagged Is flagged as unusual behavior or not. |
|
345
|
|
|
* |
|
346
|
|
|
* @return array |
|
347
|
|
|
*/ |
|
348
|
|
|
protected function filterCookie(array $logData, array $ipDetail, bool $isFlagged): array |
|
349
|
|
|
{ |
|
350
|
|
|
$isReject = false; |
|
351
|
|
|
|
|
352
|
|
|
// Let's checking cookie created by javascript.. |
|
353
|
|
|
if ($this->filterStatus['cookie']) { |
|
354
|
|
|
|
|
355
|
|
|
// Get values from data table. We will count it and save it back to data table. |
|
356
|
|
|
$logData['flag_js_cookie'] = $ipDetail['flag_js_cookie']; |
|
357
|
|
|
$logData['pageviews_cookie'] = $ipDetail['pageviews_cookie']; |
|
358
|
|
|
|
|
359
|
|
|
$c = $this->properties['cookie_name']; |
|
360
|
|
|
|
|
361
|
|
|
$jsCookie = get_request()->getCookieParams()[$c] ?? 0; |
|
362
|
|
|
|
|
363
|
|
|
// Checking if a cookie is created by JavaScript. |
|
364
|
|
|
if (!empty($jsCookie)) { |
|
365
|
|
|
if ($jsCookie == '1') { |
|
366
|
|
|
$logData['pageviews_cookie']++; |
|
367
|
|
|
|
|
368
|
|
|
} else { |
|
369
|
|
|
// Flag it if the value is not 1. |
|
370
|
|
|
$logData['flag_js_cookie']++; |
|
371
|
|
|
$isFlagged = true; |
|
372
|
|
|
} |
|
373
|
|
|
} else { |
|
374
|
|
|
// If we cannot find the cookie, flag it. |
|
375
|
|
|
$logData['flag_js_cookie']++; |
|
376
|
|
|
$isFlagged = true; |
|
377
|
|
|
} |
|
378
|
|
|
|
|
379
|
|
|
if ($logData['flag_js_cookie'] > $this->properties['limit_unusual_behavior']['cookie']) { |
|
380
|
|
|
|
|
381
|
|
|
// Ban this IP if they reached the limit. |
|
382
|
|
|
$this->action( |
|
383
|
|
|
kernel::ACTION_TEMPORARILY_DENY, |
|
384
|
|
|
kernel::REASON_EMPTY_JS_COOKIE |
|
385
|
|
|
); |
|
386
|
|
|
$isReject = true; |
|
387
|
|
|
} |
|
388
|
|
|
|
|
389
|
|
|
// Remove JS cookie and reset. |
|
390
|
|
|
if ($logData['pageviews_cookie'] > $this->properties['limit_unusual_behavior']['cookie']) { |
|
391
|
|
|
$logData['pageviews_cookie'] = 0; // Reset to 0. |
|
392
|
|
|
$logData['flag_js_cookie'] = 0; |
|
393
|
|
|
unset_superglobal($c, 'cookie'); |
|
394
|
|
|
} |
|
395
|
|
|
} |
|
396
|
|
|
|
|
397
|
|
|
return [ |
|
398
|
|
|
'is_flagged' => $isFlagged, |
|
399
|
|
|
'is_reject' => $isReject, |
|
400
|
|
|
'log_data' => $logData, |
|
401
|
|
|
]; |
|
402
|
|
|
} |
|
403
|
|
|
|
|
404
|
|
|
/** |
|
405
|
|
|
* Filter - Frequency |
|
406
|
|
|
* |
|
407
|
|
|
* @param array $logData IP data from Shieldon log table. |
|
408
|
|
|
* @param array $ipData The IP log data. |
|
409
|
|
|
* @param bool $isFlagged Is flagged as unusual behavior or not. |
|
410
|
|
|
* |
|
411
|
|
|
* @return array |
|
412
|
|
|
*/ |
|
413
|
|
|
protected function filterFrequency(array $logData, array $ipDetail, bool $isFlagged): array |
|
414
|
|
|
{ |
|
415
|
|
|
$isReject = false; |
|
416
|
|
|
|
|
417
|
|
|
if ($this->filterStatus['frequency']) { |
|
418
|
|
|
$timeSecond = []; |
|
419
|
|
|
$timeSecond['s'] = 1; |
|
420
|
|
|
$timeSecond['m'] = 60; |
|
421
|
|
|
$timeSecond['h'] = 3600; |
|
422
|
|
|
$timeSecond['d'] = 86400; |
|
423
|
|
|
|
|
424
|
|
|
foreach (array_keys($this->properties['time_unit_quota']) as $unit) { |
|
425
|
|
|
|
|
426
|
|
|
if (($logData['last_time'] - $ipDetail['first_time_' . $unit]) >= ($timeSecond[$unit] + 1)) { |
|
427
|
|
|
|
|
428
|
|
|
// For example: |
|
429
|
|
|
// (1) minutely: now > first_time_m about 61, (2) hourly: now > first_time_h about 3601, |
|
430
|
|
|
// Let's prepare to rest the the pageview count. |
|
431
|
|
|
$this->filterResetStatus[$unit] = true; |
|
432
|
|
|
|
|
433
|
|
|
} else { |
|
434
|
|
|
|
|
435
|
|
|
// If an user's pageview count is more than the time period limit |
|
436
|
|
|
// He or she will get banned. |
|
437
|
|
|
if ($logData['pageviews_' . $unit] > $this->properties['time_unit_quota'][$unit]) { |
|
438
|
|
|
|
|
439
|
|
|
$actionReason = [ |
|
440
|
|
|
's' => kernel::REASON_REACHED_LIMIT_SECOND, |
|
441
|
|
|
'm' => kernel::REASON_REACHED_LIMIT_MINUTE, |
|
442
|
|
|
'h' => kernel::REASON_REACHED_LIMIT_HOUR, |
|
443
|
|
|
'd' => kernel::REASON_REACHED_LIMIT_DAY, |
|
444
|
|
|
]; |
|
445
|
|
|
|
|
446
|
|
|
$this->action( |
|
447
|
|
|
kernel::ACTION_TEMPORARILY_DENY, |
|
448
|
|
|
$actionReason[$unit] |
|
449
|
|
|
); |
|
450
|
|
|
|
|
451
|
|
|
$isReject = true; |
|
452
|
|
|
} |
|
453
|
|
|
} |
|
454
|
|
|
} |
|
455
|
|
|
|
|
456
|
|
|
foreach ($this->filterResetStatus as $unit => $status) { |
|
457
|
|
|
// Reset the pageview check for specfic time unit. |
|
458
|
|
|
if ($status) { |
|
459
|
|
|
$logData['first_time_' . $unit] = $logData['last_time']; |
|
460
|
|
|
$logData['pageviews_' . $unit] = 0; |
|
461
|
|
|
} |
|
462
|
|
|
} |
|
463
|
|
|
} |
|
464
|
|
|
|
|
465
|
|
|
return [ |
|
466
|
|
|
'is_flagged' => $isFlagged, |
|
467
|
|
|
'is_reject' => $isReject, |
|
468
|
|
|
'log_data' => $logData, |
|
469
|
|
|
]; |
|
470
|
|
|
} |
|
471
|
|
|
} |
|
472
|
|
|
|