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<?php

/*

        [Discuz!] (C)2001-2007 Comsenz Inc.         This is NOT a freeware, use is subject to license terms

        $Id: global.func.php 13426 2008-04-15 03:37:02Z heyond $

*/

if(!defined('IN_DISCUZ')) {

        exit('Access Denied'); }

/**

* 加密或者解密用户信息 * @param $string - 加密或解密的串 * @param $operation - 加密还是解密 * @param 密钥 * @return 返回字符串 * $ckey_length 随机密钥长度 取值 0-32; * 加入随机密钥，可以令密文无任何规律，即便是原文和密钥完全相同，加密结果也会每次不同，增大破解难度。 * 取值越大，密文变动规律越大，密文变化 = 16 的 $ckey_length 次方 * 当此值为 0 时，则不产生随机密钥 */

function authcode($string, $operation = 'DECODE', $key = '', $expiry = 0) {

        $ckey_length = 4;

        $key = md5($key ? $key : $GLOBALS['discuz_auth_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));         }

}

/**

* 清理cookie */ function clearcookies() {         global $discuz_uid, $discuz_user, $discuz_pw, $discuz_secques, $adminid, $credits;         dsetcookie('sid', '', -86400 * 365);         dsetcookie('auth', '', -86400 * 365);         dsetcookie('visitedfid', '', -86400 * 365);         dsetcookie('onlinedetail', '', -86400 * 365, 0);         dsetcookie('loginuser', '', -86400 * 365);         dsetcookie('activationauth', '', -86400 * 365);

        $discuz_uid = $adminid = $credits = 0;

        $discuz_user = $discuz_pw = $discuz_secques = ''; }

/**

* 检查积分下限 * @param $creditsarray - 积分数组 * @param $coef - 积分 */ function checklowerlimit($creditsarray, $coef = 1) {         if(is_array($creditsarray)) {                 global $extcredits, $id;                 foreach($creditsarray as $id => $addcredits) {                         $addcredits = $addcredits * $coef;                         if($addcredits < 0 && ($GLOBALS['extcredits'.$id] < $extcredits[$id]['lowerlimit'] || (($GLOBALS['extcredits'.$id] + $addcredits) < $extcredits[$id]['lowerlimit']))) {                                 if($coef == 1) {                                         showmessage('credits_policy_lowerlimit');                                 } else {                                         showmessage('credits_policy_num_lowerlimit');                                 }                         }                 }         } }

/**

* 密码检测 * * @param string $md5 * @param string $verified * @param string $salt * @return *         0= Failed *         1= MD5 with salt, 2= Dual MD5, 3= Normal Md5 4= MD5-16 */

function checkmd5($md5, $verified, $salt = '') {

        if(md5($md5.$salt) == $verified) {                 $result = !empty($salt) ? 1 : 2;         } elseif(empty($salt)) {                 $result = $md5 == $verified ? 3 : ((strlen($verified) == 16 && substr($md5, 8, 16) == $verified) ? 4 : 0);         } else {                 $result = 0;         }         return $result; }

/**

* 检查模板源文件是否更新 * 当编译文件不存时强制重新编译 * 当 tplrefresh = 1 时检查文件 * 当 tplrefresh > 1 时，则根据 tplrefresh 取余，无余时则检查更新 * */ function checktplrefresh($maintpl, $subtpl, $timecompare, $templateid, $tpldir) {         global $tplrefresh;         if(empty($timecompare) || $tplrefresh == 1 || ($tplrefresh > 1 && !($GLOBALS['timestamp'] % $tplrefresh))) {                 if(empty($timecompare) || @filemtime($subtpl) > $timecompare) {                         require_once DISCUZ_ROOT.'./include/template.func.php';                         parse_template($maintpl, $templateid, $tpldir);                         return TRUE;                 }         }         return         FALSE; } ?>