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<?php |
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/** |
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* @copyright Copyright (c) 2017 Matthias Held <[email protected]> |
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* @author Matthias Held <[email protected]> |
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* @license GNU AGPL version 3 or any later version |
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* |
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* This program is free software: you can redistribute it and/or modify |
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* it under the terms of the GNU Affero General Public License as |
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* published by the Free Software Foundation, either version 3 of the |
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* License, or (at your option) any later version. |
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* |
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* This program is distributed in the hope that it will be useful, |
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* but WITHOUT ANY WARRANTY; without even the implied warranty of |
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
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* GNU Affero General Public License for more details. |
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* |
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* You should have received a copy of the GNU Affero General Public License |
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* along with this program. If not, see <https://www.gnu.org/licenses/>. |
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*/ |
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namespace OCA\RansomwareDetection\Entropy; |
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use OCP\ILogger; |
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class Entropy |
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{ |
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/** @var ILogger */ |
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private $logger; |
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/** |
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* @param IConfig $config |
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*/ |
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public function __construct( |
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ILogger $logger |
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) { |
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$this->logger = $logger; |
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} |
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/** |
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* Calculates the entropy of data. |
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* |
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* @param string $data |
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* |
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* @return float |
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*/ |
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public function calculateEntropy($data) |
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{ |
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$entropy = 0; |
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$size = strlen($data); |
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foreach (count_chars($data, 1) as $value) { |
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$p = $value / $size; |
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$entropy -= $p * log($p) / log(2); |
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} |
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return $entropy; |
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} |
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/** |
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* Calculates the standard deviation of a continoues series by passing |
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* the current number of values used to calculate the standard deviation |
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* the sum of all these values and the mean of all these values. |
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* |
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* @param float $step current value |
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* @param float $sum sum of all values |
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* @param float $mean mean of all values |
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* |
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* @return float |
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*/ |
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public function calculateStandardDeviationOfSeries($step, $sum, $mean) { |
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return sqrt((1 / $step) * $sum - pow($mean, 2)); |
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} |
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/** |
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* Calculates the mean of a continoues series by passing the old mean |
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* the new value and the number of values used to calculate the mean |
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* including the new one. |
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* |
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* @param float $oldMean |
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* @param float $value |
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* @param float $step |
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* |
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* @param float |
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*/ |
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public function calculateMeanOfSeries($oldMean, $value, $step) { |
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$mean = 0; |
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if ($step === 1) { |
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$mean = (($step - 1) / $step) + ($value / $step); |
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} else { |
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$mean = $oldMean * (($step - 1) / $step) + ($value / $step); |
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} |
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return $mean; |
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} |
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} |
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undo-ransomware /
ransomware_detection
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The issue could also be caused by a filter entry in the build configuration. If the path has been excluded in your configuration, e.g.
excluded_paths: ["lib/*"], you can move it to the dependency path list as follows:For further information see https://scrutinizer-ci.com/docs/tools/php/php-scrutinizer/#list-dependency-paths