复制代码 代码如下:
<?php
$id = "//www.rzxsoft.cn";
$token = encrypt($id, "E", "jb51");
echo "加密:".encrypt($id, "E", "jb51");
echo "<br />";
echo "解密：".encrypt($token, "D", "jb51");
/*********************************************************************
函数名称:encrypt
函数作用:加密解密字符串
使用方法:
加密 :encrypt("str","E","qingdou");
解密 :encrypt("被加密过的字符串","D","qingdou");
参数说明:
$string :需要加密解密的字符串
$operation:判断是加密还是解密:E:加密 D:解密
$key :加密的钥匙(密匙);
*********************************************************************/
function encrypt($string,$operation,$key="")
{
$src = array("/","+","=");
$dist = array("_a","_b","_c");
if($operation=="D"){$string = str_replace($dist,$src,$string);}
$key=md5($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
{
$rdate = str_replace("=","",base64_encode($result));
$rdate = str_replace($src,$dist,$rdate);
return $rdate;
}
}
?>
