<?php  
function encryptDecrypt($key, $string, $decrypt){   
    if($decrypt){   
        $decrypted = rtrim(mcrypt_decrypt(MCRYPT_RIJNDAEL_256, md5($key), base64_decode($string), MCRYPT_MODE_CBC, md5(md5($key))), "12");   
        return $decrypted;   
    }else{   
        $encrypted = base64_encode(mcrypt_encrypt(MCRYPT_RIJNDAEL_256, md5($key), $string, MCRYPT_MODE_CBC, md5(md5($key))));   
        return $encrypted;   
    }   
}   

//加密:"z0JAx4qMwcF+db5TNbp/xwdUM84snRsXvvpXuaCa4Bk="  
echo encryptDecrypt(\'password\', \'Helloweba欢迎您\',0);   
//解密:"Helloweba欢迎您"  
echo encryptDecrypt(\'password\', \'z0JAx4qMwcF+db5TNbp/xwdUM84snRsXvvpXuaCa4Bk=\',1);  
?>  

<?php  
//加密函数  
function lock_url($txt,$key=\'liiu\'){  
    $chars = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789-=+";  
    $nh = rand(0,64);  
    $ch = $chars[$nh];  
    $mdKey = md5($key.$ch);  
    $mdKey = substr($mdKey,$nh%8, $nh%8+7);  
    $txt = base64_encode($txt);  
    $tmp = \'\';  
    $i=0;$j=0;$k = 0;  
    for ($i=0; $i<strlen($txt); $i++) {  
        $k = $k == strlen($mdKey) ? 0 : $k;  
        $j = ($nh+strpos($chars,$txt[$i])+ord($mdKey[$k++]))%64;  
        $tmp .= $chars[$j];  
    }  
    return urlencode($ch.$tmp);  
}  
//解密函数  
function unlock_url($txt,$key=\'liiu\'){  
    $txt = urldecode($txt);  
    $chars = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789-=+";  
    $ch = $txt[0];  
    $nh = strpos($chars,$ch);  
    $mdKey = md5($key.$ch);  
    $mdKey = substr($mdKey,$nh%8, $nh%8+7);  
    $txt = substr($txt,1);  
    $tmp = \'\';  
    $i=0;$j=0; $k = 0;  
    for ($i=0; $i<strlen($txt); $i++) {  
        $k = $k == strlen($mdKey) ? 0 : $k;  
        $j = strpos($chars,$txt[$i])-$nh - ord($mdKey[$k++]);  
        while ($j<0) $j+=64;  
        $tmp .= $chars[$j];  
    }  
    return base64_decode($tmp);  
}  
?>  

<?php  
//改进后的算法  
//加密函数  
function lock_url($txt,$key=\'str\'){  
    $txt = $txt.$key;  
    $chars = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789-=+";  
    $nh = rand(0,64);  
    $ch = $chars[$nh];  
    $mdKey = md5($key.$ch);  
    $mdKey = substr($mdKey,$nh%8, $nh%8+7);  
    $txt = base64_encode($txt);  
    $tmp = \'\';  
    $i=0;$j=0;$k = 0;  
    for ($i=0; $i<strlen($txt); $i++) {  
        $k = $k == strlen($mdKey) ? 0 : $k;  
        $j = ($nh+strpos($chars,$txt[$i])+ord($mdKey[$k++]))%64;  
        $tmp .= $chars[$j];  
    }  
    return urlencode(base64_encode($ch.$tmp));  
}  
//解密函数  
function unlock_url($txt,$key=\'str\'){  
    $txt = base64_decode(urldecode($txt));  
    $chars = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789-=+";  
    $ch = $txt[0];  
    $nh = strpos($chars,$ch);  
    $mdKey = md5($key.$ch);  
    $mdKey = substr($mdKey,$nh%8, $nh%8+7);  
    $txt = substr($txt,1);  
    $tmp = \'\';  
    $i=0;$j=0; $k = 0;  
    for ($i=0; $i<strlen($txt); $i++) {  
        $k = $k == strlen($mdKey) ? 0 : $k;  
        $j = strpos($chars,$txt[$i])-$nh - ord($mdKey[$k++]);  
        while ($j<0) $j+=64;  
        $tmp .= $chars[$j];  
    }  
    return trim(base64_decode($tmp),$key);  
}  

?> 

<?php  

function passport_encrypt($txt, $key = \'liiu\') {   
    srand((double)microtime() * 1000000);   
    $encrypt_key = md5(rand(0, 32000));   
    $ctr = 0;   
    $tmp = \'\';   
    for($i = 0;$i < strlen($txt); $i++) {   
    $ctr = $ctr == strlen($encrypt_key) ? 0 : $ctr;   
    $tmp .= $encrypt_key[$ctr].($txt[$i] ^ $encrypt_key[$ctr++]);   
    }   
    return urlencode(base64_encode(passport_key($tmp, $key)));   
}   

function passport_decrypt($txt, $key = \'liiu\') {   
    $txt = passport_key(base64_decode(urldecode($txt)), $key);   
    $tmp = \'\';   
    for($i = 0;$i < strlen($txt); $i++) {   
    $md5 = $txt[$i];   
    $tmp .= $txt[++$i] ^ $md5;   
    }   
    return $tmp;   
}   

function passport_key($txt, $encrypt_key) {   
    $encrypt_key = md5($encrypt_key);   
    $ctr = 0;   
    $tmp = \'\';   
    for($i = 0; $i < strlen($txt); $i++) {   
    $ctr = $ctr == strlen($encrypt_key) ? 0 : $ctr;   
    $tmp .= $txt[$i] ^ $encrypt_key[$ctr++];   
    }   
    return $tmp;   
}   


$txt = "1";   
$key = "testkey";   
$encrypt = passport_encrypt($txt,$key);   
$decrypt = passport_decrypt($encrypt,$key);   

echo $encrypt."<br>";   
echo $decrypt."<br>";   

?>   

<?php  
//非常给力的authcode加密函数,Discuz!经典代码(带详解)  
//函数authcode($string, $operation, $key, $expiry)中的$string：字符串，明文或密文；$operation：DECODE表示解密，其它表示加密；$key：密匙；$expiry：密文有效期。  
function authcode($string, $operation = \'DECODE\', $key = \'\', $expiry = 0) {     
    // 动态密匙长度，相同的明文会生成不同密文就是依靠动态密匙     
    $ckey_length = 4;     

    // 密匙     
    $key = md5($key ? $key : $GLOBALS[\'discuz_auth_key\']);     

    // 密匙a会参与加解密     
    $keya = md5(substr($key, 0, 16));     
    // 密匙b会用来做数据完整性验证     
    $keyb = md5(substr($key, 16, 16));     
    // 密匙c用于变化生成的密文     
    $keyc = $ckey_length ? ($operation == \'DECODE\' ? substr($string, 0, $ckey_length): substr(md5(microtime()), -$ckey_length)) : \'\';     
    // 参与运算的密匙     
    $cryptkey = $keya.md5($keya.$keyc);     
    $key_length = strlen($cryptkey);     
    // 明文，前10位用来保存时间戳，解密时验证数据有效性，10到26位用来保存$keyb(密匙b)，   
    //解密时会通过这个密匙验证数据完整性     
    // 如果是解码的话，会从第$ckey_length位开始，因为密文前$ckey_length位保存 动态密匙，以保证解密正确     
    $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);     
    $rndkey = array();     
    // 产生密匙簿     
    for($i = 0; $i <= 255; $i++) {     
        $rndkey[$i] = ord($cryptkey[$i % $key_length]);     
    }     
    // 用固定的算法，打乱密匙簿，增加随机性，好像很复杂，实际上对并不会增加密文的强度     
    for($j = $i = 0; $i < 256; $i++) {     
        $j = ($j + $box[$i] + $rndkey[$i]) % 256;     
        $tmp = $box[$i];     
        $box[$i] = $box[$j];     
        $box[$j] = $tmp;     
    }     
    // 核心加解密部分     
    for($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;     
        // 从密匙簿得出密匙进行异或，再转成字符     
        $result .= chr(ord($string[$i]) ^ ($box[($box[$a] + $box[$j]) % 256]));     
    }     
    if($operation == \'DECODE\') {    
        // 验证数据有效性，请看未加密明文的格式     
        if((substr($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 {     
        // 把动态密匙保存在密文里，这也是为什么同样的明文，生产不同密文后能解密的原因     
        // 因为加密后的密文可能是一些特殊字符，复制过程可能会丢失，所以用base64编码     
        return $keyc.str_replace(\'=\', \'\', base64_encode($result));     
    }     
}   

$str = \'abcdef\';   
$key = \'www.helloweba.com\';   
echo authcode($str,\'ENCODE\',$key,0); //加密   
$str = \'56f4yER1DI2WTzWMqsfPpS9hwyoJnFP2MpC8SOhRrxO7BOk\';   
echo authcode($str,\'DECODE\',$key,0); //解密   

?> 

<?php  
//函数encrypt($string,$operation,$key)中$string：需要加密解密的字符串；$operation：判断是加密还是解密，E表示加密，D表示解密；$key：密匙。  
function encrypt($string,$operation,$key=\'\'){   
    $key=md5($key);   
    $key_length=strlen($key);   
      $string=$operation==\'D\'?base64_decode($string):substr(md5($string.$key),0,8).$string;   
    $string_length=strlen($string);   
    $rndkey=$box=array();   
    $result=\'\';   
    for($i=0;$i<=255;$i++){   
           $rndkey[$i]=ord($key[$i%$key_length]);   
        $box[$i]=$i;   
    }   
    for($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($operation==\'D\'){   
        if(substr($result,0,8)==substr(md5(substr($result,8).$key),0,8)){   
            return substr($result,8);   
        }else{   
            return\'\';   
        }   
    }else{   
        return str_replace(\'=\',\'\',base64_encode($result));   
    }   
}   

$str = \'abc\';   
$key = \'www.helloweba.com\';   
$token = encrypt($str, \'E\', $key);   
echo \'加密:\'.encrypt($str, \'E\', $key);   
echo \'解密：\'.encrypt($str, \'D\', $key);  

?>