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Direktori : /home/lightco1/upgrade.lightco.com.au/libraries/fof30/Encrypt/AesAdapter/ |
Current File : /home/lightco1/upgrade.lightco.com.au/libraries/fof30/Encrypt/AesAdapter/AbstractAdapter.php |
<?php /** * @package FOF * @copyright 2010-2017 Nicholas K. Dionysopoulos / Akeeba Ltd * @license GNU GPL version 2 or later */ namespace FOF30\Encrypt\AesAdapter; // Protect from unauthorized access defined('_JEXEC') or die(); /** * Abstract AES encryption class */ abstract class AbstractAdapter { /** * Trims or zero-pads a key / IV * * @param string $key The key or IV to treat * @param int $size The block size of the currently used algorithm * * @return null|string Null if $key is null, treated string of $size byte length otherwise */ public function resizeKey($key, $size) { if (empty($key)) { return null; } $keyLength = strlen($key); if (function_exists('mb_strlen')) { $keyLength = mb_strlen($key, 'ASCII'); } if ($keyLength == $size) { return $key; } if ($keyLength > $size) { if (function_exists('mb_substr')) { return mb_substr($key, 0, $size, 'ASCII'); } return substr($key, 0, $size); } return $key . str_repeat("\0", ($size - $keyLength)); } /** * Returns null bytes to append to the string so that it's zero padded to the specified block size * * @param string $string The binary string which will be zero padded * @param int $blockSize The block size * * @return string The zero bytes to append to the string to zero pad it to $blockSize */ protected function getZeroPadding($string, $blockSize) { $stringSize = strlen($string); if (function_exists('mb_strlen')) { $stringSize = mb_strlen($string, 'ASCII'); } if ($stringSize == $blockSize) { return ''; } if ($stringSize < $blockSize) { return str_repeat("\0", $blockSize - $stringSize); } $paddingBytes = $stringSize % $blockSize; return str_repeat("\0", $blockSize - $paddingBytes); } }