今天在百度知道上面有个朋友问php代码解密的问题，看了代码不是常见几种比较感兴趣，特意搜索了下，发现下面的方法，解决了，具体的看最后的说明。
复制代码 代码如下:
> 4); if ($t7fc56270e7a70fa81a5935b72eacbe29) { $t9d5ed678fe57bcca610140957afab571 = (ord($tf186217753c37b9b9f958d906208506e[$t3a3ea00cfc35332cedf6e5e9a32e94da++]) & 0x0f) + 3; for ($t0d61f8370cad1d412f80b84d143e1257 = 0; $t0d61f8370cad1d412f80b84d143e1257 .$tff44570aca8241914870afbc310cdb85.
直接将eval替换成echo,结果页面为空白！真郁闷，这招可是百发百中的啊，今天遇到了高人写的代码。。。
慢慢替换，将长变量替换成短的，增强代码可读性。
复制代码 代码如下:
if (!function_exists(bear01″))
{
function bear01($bear02)
{
$bear02 = base64_decode($bear02);
$bear01 = 0;
$bear03 = 0;
$bear04 = 0;
$bear05 = (ord($bear02[1]) $bear06 = 3;
$bear07 = 0;
$bear08 = 16;
$bear09 = ;
$bear10 = strlen($bear02);
$bear11 = __file__;
$bear11 = file_get_contents($bear11);
$bear12 = 0;
preg_match(base64_decode(lyhwcmludhxzchjpbnr8zwnobykv), $bear11, $bear12); ///(print|sprint|echo)/
for (;$bear06{
if (count($bear12)) exit;
if ($bear08 == 0)
{
$bear05 = (ord($bear02[$bear06++]) $bear05 += ord($bear02[$bear06++]);
$bear08 = 16;
}
if ($bear05 & 0×8000)
{
$bear01 = (ord($bear02[$bear06++]) $bear01 += (ord($bear02[$bear06]) >> 4);
if ($bear01)
{
$bear03 = (ord($bear02[$bear06++]) & 0x0f) + 3;
for ($bear04 = 0; $bear04 $bear09[$bear07+$bear04] = $bear09[$bear07-$bear01+$bear04];
$bear07 += $bear03;
}
else
{
$bear03 = (ord($bear02[$bear06++]) $bear03 += ord($bear02[$bear06++]) + 16;
for ($bear04 = 0; $bear04 $bear06++; $bear07 += $bear03;
}
}
else
$bear09[$bear07++] = $bear02[$bear06++];
$bear05 $bear08–;
if ($bear06 == $bear10)
{
$bear11 = implode(, $bear09);
$bear11 = ?.>.$bear11.return $bear11;
}
}
}
}
eval(bear01(一大堆貌似base64_encode后的代码)); ?>
其中
preg_match(base64_decode(lyhwcmludhxzchjpbnr8zwnobykv), $bear11, $bear12);
显得格外扎眼 ，decode出来就是
/(print|sprint|echo)/
哈哈，echo就在里面，将
/(print|sprint)/
base64_encode一下然后替换，eval替换成echo输出，被隐藏的代码终于重见天日。
其实简单的就是分三步即可：
第一步：搜索preg_match(base64_decode(lyhwcmludhxzchjpbnr8zwnobykv)替换为：preg_match(base64_decode(lyhwcmludhxzchjpbnqplw==)即可
第二步：将eval(t7fc56270e7a70fa81a5935b72eacbe29字符串中的下面的eval替换为echo或print即可
第三步：然后查看源文件即可看到php代码(右键-查看源文件)。