MRBS 1.12.2 等保2.0二级整改完整提交

包含：登录失败锁定、90天密码有效期、30分钟会话超时、
强制改密、登录审计日志、屏幕水印、企业背景图、
备案信息固定底部、favicon、登录页JS修复等全部改动

web/lib/Defuse/Crypto/DerivedKeys.php

@@ -0,0 +1,50 @@
+<?php
+
+namespace Defuse\Crypto;
+
+/**
+ * Class DerivedKeys
+ * @package Defuse\Crypto
+ */
+final class DerivedKeys
+{
+    /**
+     * @var string
+     */
+    private $akey = '';
+
+    /**
+     * @var string
+     */
+    private $ekey = '';
+
+    /**
+     * Returns the authentication key.
+     * @return string
+     */
+    public function getAuthenticationKey()
+    {
+        return $this->akey;
+    }
+
+    /**
+     * Returns the encryption key.
+     * @return string
+     */
+    public function getEncryptionKey()
+    {
+        return $this->ekey;
+    }
+
+    /**
+     * Constructor for DerivedKeys.
+     *
+     * @param string $akey
+     * @param string $ekey
+     */
+    public function __construct($akey, $ekey)
+    {
+        $this->akey = $akey;
+        $this->ekey = $ekey;
+    }
+}