add methods to decrypt return data from router

[GitHub/Stricted/speedport-hybrid-php-api.git] / CryptLib / Random / AbstractMixer.php

diff --git a/CryptLib/Random/AbstractMixer.php b/CryptLib/Random/AbstractMixer.php
new file mode 100644 (file)
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+++ b/CryptLib/Random/AbstractMixer.php
@@ -0,0 +1,115 @@
+<?php
+/**
+ * An abstract mixer to implement a common mixing strategy
+ *
+ * PHP version 5.3
+ *
+ * @category  PHPCryptLib
+ * @package   Random
+ * @author    Anthony Ferrara <ircmaxell@ircmaxell.com>
+ * @copyright 2011 The Authors
+ * @license    http://www.opensource.org/licenses/mit-license.html  MIT License
+ * @version   Build @@version@@
+ */
+
+namespace CryptLib\Random;
+
+/**
+ * An abstract mixer to implement a common mixing strategy
+ *
+ * @see      http://tools.ietf.org/html/rfc4086#section-5.2
+ * @category PHPCryptLib
+ * @package  Random
+ * @author   Anthony Ferrara <ircmaxell@ircmaxell.com>
+ */
+abstract class AbstractMixer implements \CryptLib\Random\Mixer {
+
+    /**
+     * Get the block size (the size of the individual blocks used for the mixing)
+     * 
+     * @return int The block size
+     */
+    abstract protected function getPartSize();
+
+    /**
+     * Mix 2 parts together using one method
+     *
+     * @param string $part1 The first part to mix
+     * @param string $part2 The second part to mix
+     * 
+     * @return string The mixed data
+     */
+    abstract protected function mixParts1($part1, $part2);
+
+    /**
+     * Mix 2 parts together using another different method
+     *
+     * @param string $part1 The first part to mix
+     * @param string $part2 The second part to mix
+     * 
+     * @return string The mixed data
+     */
+    abstract protected function mixParts2($part1, $part2);
+
+    /**
+     * Mix the provided array of strings into a single output of the same size
+     *
+     * All elements of the array should be the same size.
+     *
+     * @param array $parts The parts to be mixed
+     *
+     * @return string The mixed result
+     */
+    public function mix(array $parts) {
+        if (empty($parts)) {
+            return '';
+        }
+        $len        = strlen($parts[0]);
+        $parts      = $this->normalizeParts($parts);
+        $stringSize = count($parts[0]);
+        $partsSize  = count($parts);
+        $result     = '';
+        $offset     = 0;
+        for ($i = 0; $i < $stringSize; $i++) {
+            $stub = $parts[$offset][$i];
+            for ($j = 1; $j < $partsSize; $j++) {
+                $newKey = $parts[($j + $offset) % $partsSize][$i];
+                //Alternately mix the output for each source
+                if ($j % 2 == 1) {
+                    $stub ^= $this->mixParts1($stub, $newKey);
+                } else {
+                    $stub ^= $this->mixParts2($stub, $newKey);
+                }
+            }
+            $result .= $stub;
+            $offset  = ($offset + 1) % $partsSize;
+        }
+        return substr($result, 0, $len);
+    }
+
+    /**
+     * Normalize the part array and split it block part size.  
+     * 
+     * This will make all parts the same length and a multiple
+     * of the part size
+     *
+     * @param array $parts The parts to normalize
+     * 
+     * @return array The normalized and split parts
+     */
+    protected function normalizeParts(array $parts) {
+        $blockSize = $this->getPartSize();
+        $callback  = function($value) {
+            return strlen($value);
+        };
+        $maxSize = max(array_map($callback, $parts));
+        if ($maxSize % $blockSize != 0) {
+            $maxSize += $blockSize - ($maxSize % $blockSize);
+        }
+        foreach ($parts as &$part) {
+            $part = str_pad($part, $maxSize, chr(0));
+            $part = str_split($part, $blockSize);
+        }
+        return $parts;
+    }
+}