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<?php |
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namespace PragmaRX\Firewall\Support; |
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use Carbon\Carbon; |
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use PragmaRX\Firewall\Events\AttackDetected; |
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use PragmaRX\Firewall\Firewall; |
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use PragmaRX\Firewall\Repositories\Cache\Cache; |
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use PragmaRX\Support\Config; |
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class AttackBlocker |
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{ |
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use ServiceInstances; |
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/** |
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* The request record. |
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* |
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* @var array |
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*/ |
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protected $record = [ |
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'ip' => null, |
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'country' => null, |
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]; |
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/** |
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* The ip address. |
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* |
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* @var string |
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*/ |
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protected $ipAddress; |
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/** |
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* The cache key. |
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* |
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* @var string |
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*/ |
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protected $key; |
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/** |
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* The max request count. |
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* |
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* @var int |
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*/ |
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protected $maxRequestCount; |
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/** |
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* The max request count. |
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* |
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* @var int |
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*/ |
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protected $maxSeconds; |
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/** |
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* The firewall instance. |
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* |
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* @var Firewall |
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*/ |
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protected $firewall; |
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/** |
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* The country. |
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* |
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* @var string |
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*/ |
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protected $country; |
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/** |
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* The enabled items. |
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* |
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* @var \Illuminate\Support\Collection |
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*/ |
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protected $enabledItems; |
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/** |
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* AttackBlocker constructor. |
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*/ |
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72 |
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public function __construct() |
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{ |
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72 |
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$this->loadConfig(); |
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} |
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/** |
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* Blacklist the IP address. |
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* |
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* @param $record |
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* |
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* @return bool |
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*/ |
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protected function blacklist($record) |
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{ |
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6 |
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if ($record['isBlacklisted']) { |
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2 |
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return false; |
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} |
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6 |
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$blacklistUnknown = $this->config()->get("attack_blocker.action.{$record['type']}.blacklist_unknown"); |
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$blackWhitelisted = $this->config()->get("attack_blocker.action.{$record['type']}.blacklist_whitelisted"); |
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if ($blacklistUnknown || $blackWhitelisted) { |
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$record['isBlacklisted'] = true; |
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$ipAddress = $record['type'] == 'country' ? 'country:'.$record['country_code'] : $record['ipAddress']; |
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$this->firewall->blacklist($ipAddress, $blackWhitelisted); |
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$this->save($record); |
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return true; |
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} |
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return false; |
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} |
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/** |
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* Check for expiration. |
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* |
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* @return void |
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*/ |
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protected function checkExpiration() |
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{ |
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$this->enabledItems->each(function ($index, $type) { |
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if (($this->now()->diffInSeconds($this->record[$type]['lastRequestAt'])) <= ($this->getMaxSecondsForType($type))) { |
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return $this->record; |
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} |
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return $this->record[$type] = $this->getEmptyRecord($this->record[$type]['key'], $type); |
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}); |
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} |
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/** |
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* Get an empty record. |
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* |
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* @return array |
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*/ |
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protected function getEmptyRecord($key, $type) |
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{ |
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return $this->makeRecord($key, $type); |
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} |
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/** |
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* Get a timestamp for the time the cache should expire. |
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* |
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* @param $type |
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* |
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* @return \Carbon\Carbon |
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*/ |
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protected function getExpirationTimestamp($type) |
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{ |
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return $this->now()->addSeconds($this->getMaxSecondsForType($type)); |
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} |
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/** |
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* Search geo localization by ip. |
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* |
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* @param $ipAddress |
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* |
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* @return array|null |
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*/ |
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protected function getGeo($ipAddress) |
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{ |
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return $this->firewall->getGeoIp()->searchAddr($ipAddress); |
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} |
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/** |
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* Get max request count from config. |
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* |
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* @param string $type |
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* |
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* @return int |
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*/ |
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protected function getMaxRequestCountForType($type = 'ip') |
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{ |
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return !is_null($this->maxRequestCount) |
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? $this->maxRequestCount |
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: ($this->maxRequestCount = $this->config()->get("attack_blocker.allowed_frequency.{$type}.requests")); |
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} |
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/** |
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* Get max seconds from config. |
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* |
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* @param $type |
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* |
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* @return int |
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*/ |
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protected function getMaxSecondsForType($type) |
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{ |
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return !is_null($this->maxSeconds) |
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? $this->maxSeconds |
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: ($this->maxSeconds = $this->config()->get("attack_blocker.allowed_frequency.{$type}.seconds")); |
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} |
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/** |
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* Get the response configuration. |
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* |
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* @return array |
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*/ |
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protected function getResponseConfig() |
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{ |
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return $this->config()->get('attack_blocker.response'); |
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} |
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/** |
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* Increment request count. |
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* |
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* @return void |
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*/ |
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protected function increment() |
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{ |
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$this->enabledItems->each(function ($index, $type) { |
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$this->save($type, ['requestCount' => $this->record[$type]['requestCount'] + 1]); |
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}); |
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} |
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/** |
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* Check if this is an attack. |
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* |
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* @return bool |
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*/ |
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protected function isAttack() |
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{ |
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return $this->enabledItems->filter(function ($index, $type) { |
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if (!$this->isWhitelisted($type) && $this->record[$type]['requestCount'] > $this->getMaxRequestCountForType($type)) { |
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$this->takeAction($this->record[$type]); |
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return true; |
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} |
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7 |
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})->count() > 0; |
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} |
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/** |
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* Check for attacks. |
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* |
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* @param $ipAddress |
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* |
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* @return bool |
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*/ |
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public function isBeingAttacked($ipAddress) |
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{ |
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8 |
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if (!$this->isEnabled()) { |
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1 |
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return false; |
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} |
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7 |
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$this->loadRecord($ipAddress); |
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return $this->isAttack(); |
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} |
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/** |
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* Get enabled state. |
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* |
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* @return bool |
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*/ |
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8 |
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protected function isEnabled() |
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{ |
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return count($this->enabledItems) > 0; |
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} |
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/** |
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* Is the current user whitelisted? |
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* |
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* @param $type |
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* |
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* @return bool |
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*/ |
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7 |
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private function isWhitelisted($type) |
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{ |
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7 |
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return $this->firewall->whichList($this->record[$type]['ipAddress']) == 'whitelist' && |
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7 |
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$this->config()->get("attack_blocker.action.{$this->record[$type]['type']}.blacklist_whitelisted"); |
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} |
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/** |
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* Load the configuration. |
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* |
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* @return void |
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*/ |
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private function loadConfig() |
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{ |
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72 |
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$this->enabledItems = collect($this->config()->get('attack_blocker.enabled'))->filter(function ($item) { |
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72 |
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return $item === true; |
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72 |
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}); |
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72 |
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} |
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284
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/** |
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* Load a record. |
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* |
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* @param $ipAddress |
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* |
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* @return void |
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*/ |
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7 |
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protected function loadRecord($ipAddress) |
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{ |
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7 |
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$this->ipAddress = $ipAddress; |
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7 |
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$this->loadRecordItems(); |
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297
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7 |
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$this->checkExpiration(); |
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7 |
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$this->increment(); |
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7 |
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} |
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302
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/** |
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303
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* Load all record items. |
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* |
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* @return void |
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*/ |
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protected function loadRecordItems() |
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308
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{ |
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7 |
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$this->enabledItems->each(function ($index, $type) { |
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7 |
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if (is_null($this->record[$type] = $this->cache()->get($key = $this->makeKeyForType($type, $this->ipAddress)))) { |
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7 |
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$this->record[$type] = $this->getEmptyRecord($key, $type); |
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} |
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7 |
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}); |
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7 |
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} |
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315
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316
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/** |
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317
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* Write to the log. |
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318
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* |
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319
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* @param $string |
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320
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* |
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321
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* @return void |
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322
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*/ |
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323
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7 |
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protected function log($string) |
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324
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{ |
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325
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7 |
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$this->firewall->log($string); |
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7 |
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} |
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327
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328
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/** |
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329
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* Send attack the the log. |
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330
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* |
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331
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* @param $record |
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332
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* |
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333
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* @return void |
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334
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*/ |
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335
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6 |
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protected function logAttack($record) |
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336
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{ |
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337
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6 |
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$this->log("Attacker detected - IP: {$record['ipAddress']} - Request count: {$record['requestCount']}"); |
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338
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6 |
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} |
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339
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340
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/** |
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341
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* Get the current date time. |
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342
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* |
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343
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* @return Carbon |
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344
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*/ |
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345
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7 |
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private function now() |
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346
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{ |
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347
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7 |
|
Carbon::setTestNow(); |
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348
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349
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7 |
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return Carbon::now(); |
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350
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} |
|
351
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352
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|
/** |
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353
|
|
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* Make a response. |
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354
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* |
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355
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* @return null|\Illuminate\Http\Response |
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356
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|
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*/ |
|
357
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3 |
|
public function responseToAttack() |
|
358
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|
|
{ |
|
359
|
3 |
|
if ($this->isAttack()) { |
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360
|
2 |
|
return (new Responder())->respond($this->getResponseConfig(), $this->record); |
|
361
|
|
|
} |
|
362
|
2 |
|
} |
|
363
|
|
|
|
|
364
|
|
|
/** |
|
365
|
|
|
* Make a hashed key. |
|
366
|
|
|
* |
|
367
|
|
|
* @param $field |
|
368
|
|
|
* |
|
369
|
|
|
* @return string |
|
370
|
|
|
*/ |
|
371
|
7 |
|
public function makeHashedKey($field) |
|
372
|
|
|
{ |
|
373
|
7 |
|
return hash( |
|
374
|
7 |
|
'sha256', |
|
375
|
7 |
|
$this->config()->get('attack_blocker.cache_key_prefix').'-'.$field |
|
376
|
|
|
); |
|
377
|
|
|
} |
|
378
|
|
|
|
|
379
|
|
|
/** |
|
380
|
|
|
* Make the cache key to record countries. |
|
381
|
|
|
* |
|
382
|
|
|
* @param $ipAddress |
|
383
|
|
|
* |
|
384
|
|
|
* @return string|null |
|
385
|
|
|
*/ |
|
386
|
7 |
|
protected function makeKeyForType($type, $ipAddress) |
|
387
|
|
|
{ |
|
388
|
7 |
|
if ($type == 'country') { |
|
389
|
6 |
|
$geo = $this->getGeo($ipAddress); |
|
390
|
|
|
|
|
391
|
6 |
|
if (is_null($geo)) { |
|
392
|
3 |
|
$this->log("No GeoIp info for {$ipAddress}, is it installed?"); |
|
393
|
|
|
} |
|
394
|
|
|
|
|
395
|
6 |
|
if (!is_null($geo) && $this->country = $geo['country_code']) { |
|
396
|
3 |
|
return $this->makeHashedKey($this->country); |
|
397
|
|
|
} |
|
398
|
|
|
|
|
399
|
3 |
|
unset($this->enabledItems['country']); |
|
400
|
|
|
|
|
401
|
3 |
|
return; |
|
402
|
|
|
} |
|
403
|
|
|
|
|
404
|
7 |
|
return $this->makeHashedKey($this->ipAddress = $ipAddress); |
|
405
|
|
|
} |
|
406
|
|
|
|
|
407
|
|
|
/** |
|
408
|
|
|
* Make a record. |
|
409
|
|
|
* |
|
410
|
|
|
* @param $key |
|
411
|
|
|
* @param $type |
|
412
|
|
|
* |
|
413
|
|
|
* @return array |
|
414
|
|
|
*/ |
|
415
|
7 |
|
protected function makeRecord($key, $type) |
|
416
|
|
|
{ |
|
417
|
7 |
|
$geo = $this->getGeo($this->ipAddress); |
|
418
|
|
|
|
|
419
|
|
|
return [ |
|
420
|
7 |
|
'type' => $type, |
|
421
|
|
|
|
|
422
|
7 |
|
'key' => $key, |
|
423
|
|
|
|
|
424
|
7 |
|
'ipAddress' => $this->ipAddress, |
|
425
|
|
|
|
|
426
|
7 |
|
'requestCount' => 0, |
|
427
|
|
|
|
|
428
|
7 |
|
'firstRequestAt' => $this->now(), |
|
429
|
|
|
|
|
430
|
7 |
|
'lastRequestAt' => $this->now(), |
|
431
|
|
|
|
|
432
|
|
|
'isBlacklisted' => false, |
|
433
|
|
|
|
|
434
|
|
|
'wasNotified' => false, |
|
435
|
|
|
|
|
436
|
7 |
|
'userAgent' => request()->server('HTTP_USER_AGENT'), |
|
437
|
|
|
|
|
438
|
7 |
|
'server' => request()->server(), |
|
439
|
|
|
|
|
440
|
7 |
|
'geoIp' => $geo, |
|
441
|
|
|
|
|
442
|
7 |
|
'country_name' => $geo ? $geo['country_name'] : null, |
|
443
|
|
|
|
|
444
|
7 |
|
'country_code' => $geo ? $geo['country_code'] : null, |
|
445
|
|
|
|
|
446
|
7 |
|
'host' => gethostbyaddr($this->ipAddress), |
|
447
|
|
|
]; |
|
448
|
|
|
} |
|
449
|
|
|
|
|
450
|
|
|
/** |
|
451
|
|
|
* Send notifications. |
|
452
|
|
|
* |
|
453
|
|
|
* @param $record |
|
454
|
|
|
* |
|
455
|
|
|
* @return void |
|
456
|
|
|
*/ |
|
457
|
6 |
|
protected function notify($record) |
|
458
|
|
|
{ |
|
459
|
6 |
|
if (!$record['wasNotified'] && $this->config()->get('notifications.enabled')) { |
|
460
|
5 |
|
$this->save($record['type'], ['wasNotified' => true]); |
|
461
|
|
|
|
|
462
|
5 |
|
collect($this->config()->get('notifications.channels'))->filter(function ($value, $channel) use ($record) { |
|
463
|
|
|
try { |
|
464
|
5 |
|
event(new AttackDetected($record, $channel)); |
|
465
|
|
|
} catch (\Exception $exception) { |
|
466
|
|
|
info($exception); |
|
467
|
|
|
} |
|
468
|
5 |
|
}); |
|
469
|
|
|
} |
|
470
|
6 |
|
} |
|
471
|
|
|
|
|
472
|
|
|
/** |
|
473
|
|
|
* Renew first request timestamp, to keep the offender blocked. |
|
474
|
|
|
* |
|
475
|
|
|
* @param $record |
|
476
|
|
|
* |
|
477
|
|
|
* @return void |
|
478
|
|
|
*/ |
|
479
|
6 |
|
protected function renew($record) |
|
480
|
|
|
{ |
|
481
|
6 |
|
$this->save($record['type'], ['lastRequestAt' => $this->now()]); |
|
482
|
6 |
|
} |
|
483
|
|
|
|
|
484
|
|
|
/** |
|
485
|
|
|
* Set firewall. |
|
486
|
|
|
* |
|
487
|
|
|
* @param Firewall $firewall |
|
488
|
|
|
* |
|
489
|
|
|
* @return void |
|
490
|
|
|
*/ |
|
491
|
72 |
|
public function setFirewall($firewall) |
|
492
|
|
|
{ |
|
493
|
72 |
|
$this->firewall = $firewall; |
|
494
|
72 |
|
} |
|
495
|
|
|
|
|
496
|
|
|
/** |
|
497
|
|
|
* Store record on cache. |
|
498
|
|
|
* |
|
499
|
|
|
* @param $type |
|
500
|
|
|
* @param array $items |
|
501
|
|
|
* |
|
502
|
|
|
* @return array |
|
503
|
|
|
*/ |
|
504
|
7 |
|
protected function save($type, $items = []) |
|
505
|
|
|
{ |
|
506
|
7 |
|
if (is_array($type)) { |
|
507
|
4 |
|
$items = $type; |
|
508
|
|
|
|
|
509
|
4 |
|
$type = $type['type']; |
|
510
|
|
|
} |
|
511
|
|
|
|
|
512
|
7 |
|
$this->record[$type] = array_merge($this->record[$type], $items); |
|
513
|
|
|
|
|
514
|
7 |
|
$this->cache()->put($this->record[$type]['key'], $this->record[$type], $this->getExpirationTimestamp($type)); |
|
|
|
|
|
|
515
|
|
|
|
|
516
|
7 |
|
return $this->record[$type]; |
|
517
|
|
|
} |
|
518
|
|
|
|
|
519
|
|
|
/** |
|
520
|
|
|
* Take the necessary action to keep the offender blocked. |
|
521
|
|
|
* |
|
522
|
|
|
* @return void |
|
523
|
|
|
*/ |
|
524
|
6 |
|
protected function takeAction($record) |
|
525
|
|
|
{ |
|
526
|
6 |
|
$this->renew($record); |
|
527
|
|
|
|
|
528
|
6 |
|
$this->blacklist($record); |
|
529
|
|
|
|
|
530
|
6 |
|
$this->notify($record); |
|
531
|
|
|
|
|
532
|
6 |
|
$this->logAttack($record); |
|
533
|
6 |
|
} |
|
534
|
|
|
} |
|
535
|
|
|
|
It seems like the type of the argument is not accepted by the function/method which you are calling.
In some cases, in particular if PHP’s automatic type-juggling kicks in this might be fine. In other cases, however this might be a bug.
We suggest to add an explicit type cast like in the following example: