add methods to decrypt return data from router

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

diff --git a/CryptLib/Random/Source/MicroTime.php b/CryptLib/Random/Source/MicroTime.php
new file mode 100644 (file)
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+++ b/CryptLib/Random/Source/MicroTime.php
@@ -0,0 +1,91 @@
+<?php
+/**
+ * The Microtime Random Number Source
+ *
+ * This uses the current micro-second (looped several times) for a **very** weak
+ * random number source.  This is only useful when combined with several other
+ * stronger sources
+ *
+ * PHP version 5.3
+ *
+ * @category   PHPCryptLib
+ * @package    Random
+ * @subpackage Source
+ * @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\Source;
+
+use CryptLib\Core\Strength;
+
+/**
+ * The Microtime Random Number Source
+ *
+ * This uses the current micro-second (looped several times) for a **very** weak
+ * random number source.  This is only useful when combined with several other
+ * stronger sources
+ *
+ * @category   PHPCryptLib
+ * @package    Random
+ * @subpackage Source
+ * @author     Anthony Ferrara <ircmaxell@ircmaxell.com>
+ * @codeCoverageIgnore
+ */
+class MicroTime implements \CryptLib\Random\Source {
+
+    private $state = null;
+
+    /**
+     * Return an instance of Strength indicating the strength of the source
+     *
+     * @return Strength An instance of one of the strength classes
+     */
+    public static function getStrength() {
+        return new Strength(Strength::VERYLOW);
+    }
+
+    public function __construct() {
+        $state = '';
+        if (function_exists('posix_times')) {
+            $state .= serialize(posix_times());
+        }
+        $state      .= getmypid() . memory_get_usage();
+        $state      .= serialize($_ENV);
+        $this->state = hash('sha512', $state, true);
+    }
+
+    /**
+     * Generate a random string of the specified size
+     *
+     * @param int $size The size of the requested random string
+     *
+     * @return string A string of the requested size
+     */
+    public function generate($size) {
+        $result      = '';
+        $seed        = microtime() . memory_get_usage();
+        $this->state = hash('sha512', $this->state . $seed, true);
+        /**
+         * Make the generated randomness a bit better by forcing a GC run which
+         * should complete in a indeterminate amount of time, hence improving
+         * the strength of the randomness a bit. It's still not crypto-safe,
+         * but at least it's more difficult to predict.
+         */
+        gc_collect_cycles();
+        for ($i = 0; $i < $size; $i += 8) {
+            $seed        = $this->state . microtime() . pack('N', $i);
+            $this->state = hash('sha512', $seed, true);
+            /**
+             * We only use the first 8 bytes here to prevent exposing the state
+             * in its entirety, which could potentially expose other random 
+             * generations in the future (in the same process)...
+             */
+            $result .= substr($this->state, 0, 8);
+        }
+        return substr($result, 0, $size);
+    }
+
+}