Discuz! X，防止uc_server(UCenter)被随意访问

Discuz! X的uc_server是可以随意访问的，这样并不利于安全性。下面这个方法可以增强安全性。

功能说明：uc_server/admin.php是ucenter默认的后台地址，正常情况下可以直接访问，为了防止某些恶意访问的情况，可以修改以下内容进行安全性能提升。

适用版本：Discuz!x1-x3.4适用情况：ucenter在论坛根目录下

修改后效果：未登录Discuz论坛或不在指定的管理组，打开uc_server/admin.php提示404

具体实施方案：

打开uc_server/model/admin.php

找到：

$this->cookie_status = isset($_COOKIE['sid']) ? 1 : 0;

下面加入以下代码：

if(!$this->cookie_status){
                        include UC_ROOT.'../config/config_global.php';
                        $cookiepre = $_config['cookie']['cookiepre'].substr(md5($_config['cookie']['cookiepath'].'|'.$_config['cookie']['cookiedomain']), 0, 4).'_';
                        $auth = addslashes($_COOKIE[$cookiepre.'auth']);
                        if(empty($_config['cookie']['saltkey'])) {
                                $_config['cookie']['saltkey'] = addslashes($_COOKIE[$cookiepre.'saltkey']);
                        }
                        $authkey = md5($_config['security']['authkey'].$_config['cookie']['saltkey']);
                        $auth = daddslashes(explode("\t", $this->dauthcode($auth, 'DECODE',$authkey)));
                        list($discuz_pw, $discuz_uid) = empty($auth) || count($auth) < 2 ? array('', '') : $auth;
                        $discuz_uid = intval($discuz_uid);
                        $groupid = $this->db->result_first("SELECT groupid FROM ".$_config['db'][1]['tablepre']."common_member WHERE uid='$discuz_uid'");
                        if(!in_array($groupid,array('1','2'))){
                                 header("HTTP/1.1 404 Not Found");header("Status: 404 Not Found");exit;
                        }
                }

这里增加用户组：

array('1','2')

找到：

function __construct() {
                $this->adminbase();
        }

下面加入以下代码：

function dauthcode($string, $operation = 'DECODE', $key = '', $expiry = 0) {
                $ckey_length = 4;
                $key = md5($key );
                $keya = md5(substr($key, 0, 16));
                $keyb = md5(substr($key, 16, 16));
                $keyc = $ckey_length ? ($operation == 'DECODE' ? substr($string, 0, $ckey_length): substr(md5(microtime()), -$ckey_length)) : '';

                $cryptkey = $keya.md5($keya.$keyc);
                $key_length = strlen($cryptkey);

                $string = $operation == 'DECODE' ? base64_decode(substr($string, $ckey_length)) : sprintf('%010d', $expiry ? $expiry + time() : 0).substr(md5($string.$keyb), 0, 16).$string;
                $string_length = strlen($string);

                $result = '';
                $box = range(0, 255);

                $rndkey = array();
                for($i = 0; $i <= 255; $i++) {
                        $rndkey[$i] = ord($cryptkey[$i % $key_length]);
                }

                for($j = $i = 0; $i < 256; $i++) {
                        $j = ($j + $box[$i] + $rndkey[$i]) % 256;
                        $tmp = $box[$i];
                        $box[$i] = $box[$j];
                        $box[$j] = $tmp;
                }

                for($a = $j = $i = 0; $i < $string_length; $i++) {
                        $a = ($a + 1) % 256;
                        $j = ($j + $box[$a]) % 256;
                        $tmp = $box[$a];
                        $box[$a] = $box[$j];
                        $box[$j] = $tmp;
                        $result .= chr(ord($string[$i]) ^ ($box[($box[$a] + $box[$j]) % 256]));
                }

                if($operation == 'DECODE') {
                        if((substr($result, 0, 10) == 0 || substr($result, 0, 10) - time() > 0) && substr($result, 10, 16) == substr(md5(substr($result, 26).$keyb), 0, 16)) {
                                return substr($result, 26);
                        } else {
                                return '';
                        }
                } else {
                        return $keyc.str_replace('=', '', base64_encode($result));
                }

        }