?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; $istrlen($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; $istrlen($txt); $i++) { 
 $k = $k == strlen($mdKey) ? 0 : $k; 
 $j = strpos($chars,$txt[$i])-$nh - ord($mdKey[$k++]); 
 while ($j0) $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; $istrlen($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; $istrlen($txt); $i++) { 
 $k = $k == strlen($mdKey) ? 0 : $k; 
 $j = strpos($chars,$txt[$i])-$nh - ord($mdKey[$k++]); 
 while ($j0) $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=$i=0;$i256;$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); 

?>