add methods to decrypt return data from router

[GitHub/Stricted/speedport-hybrid-php-api.git] / CryptLib / Encryption / PackingMode / PKCS7.php

diff --git a/CryptLib/Encryption/PackingMode/PKCS7.php b/CryptLib/Encryption/PackingMode/PKCS7.php
new file mode 100644 (file)
index 0000000..603e4fb
--- /dev/null
+++ b/CryptLib/Encryption/PackingMode/PKCS7.php
@@ -0,0 +1,62 @@
+<?php
+/**
+ * A packing mode implementation for PKCS7 padding
+ *
+ * PHP version 5.3
+ *
+ * @see        http://tools.ietf.org/html/rfc2315
+ * @category   PHPCryptLib
+ * @package    Encryption
+ * @subpackage PackingMode
+ * @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\Encryption\PackingMode;
+
+/**
+ * A packing mode implementation for PKCS7 padding
+ *
+ * PHP version 5.3
+ *
+ * @see        http://tools.ietf.org/html/rfc2315
+ * @category   PHPCryptLib
+ * @package    Encryption
+ * @subpackage PackingMode
+ * @author     Anthony Ferrara <ircmaxell@ircmaxell.com>
+ */
+class PKCS7 implements \CryptLib\Encryption\PackingMode {
+
+    /**
+     * Pad the string to the specified size
+     *
+     * @param string $string    The string to pad
+     * @param int    $blockSize The size to pad to
+     *
+     * @return string The padded string
+     */
+    public function pad($string, $blockSize = 32) {
+        $pad = $blockSize - (strlen($string) % $blockSize);
+        return $string . str_repeat(chr($pad), $pad);
+    }
+
+    /**
+     * Strip the padding from the supplied string
+     *
+     * @param string $string The string to trim
+     *
+     * @return string The unpadded string
+     */
+    public function strip($string) {
+        $end  = substr($string, -1);
+        $last = ord($end);
+        $len  = strlen($string) - $last;
+        if (substr($string, $len) == str_repeat($end, $last)) {
+            return substr($string, 0, $len);
+        }
+        return false;
+    }
+
+}