php !function_exists(T7FC56270E7A70FA81A5935B72EACBE29))代码解密

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)。