[WeChall] Blinded by the lighter

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Blinded by the lighter (MySQL, Exploit)

Blinded by the lighter

This challenge is the sequel to the "Blinded by the light" challenge.
Again your mission is to extract an md5 password hash out of the database.
This time your limit for this blind sql injection are 33 queries.
Also you have to accomplish this task 3 times consecutively, to prove you have solved the challenge.
You are also given the sourcecode of the vulnerable script, also as highlighted version.
To restart the challenge, you can execute a reset.
On the run to the great gig.
Thanks go out to dloser for his help in developing and testing the challenge.

Good luck!

GeSHi`ed PHP code for vuln.php

<?php
########################
### Not vuln install ###
########################
/** * Get the database object.
 * @return GDO_Database
 */
function blightDB()
{        static $db;
        if (!isset($db))
        {
                if (false === ($db = gdo_db_instance('localhost', BLIGHT2_USER, BLIGHT2_PASS, BLIGHT2_DB)))
                {                        die('Cannot connect to db!');
                }
                $db->setVerbose(false);
                $db->setLogging(false);
                $db->setEMailOnError(false);                $db->setDieOnError(false);
        }
        return $db;
}
 /**
 * Create the database table.
 * @return true|false
 */
function blightInstall(){
        $db = blightDB();
        $query =
                "CREATE TABLE IF NOT EXISTS blight (".
                "sessid INT(11) UNSIGNED PRIMARY KEY NOT NULL, ".                "password CHAR(32) CHARACTER SET ascii COLLATE ascii_general_ci NOT NULL, ".
                "attemp INT(11) UNSIGNED NOT NULL DEFAULT 0 ".
                ") ENGINE=myISAM";
        return $db->queryWrite($query);
} 
 
##################
### VULNERABLE ###
##################/**
 * The vulnerable login function.
 * @param string $password The unescaped string :O
 * @return true|false
 */function blightVuln($password)
{
        # Do not mess with other sessions!
        if ( (strpos($password, '/*') !== false) || (stripos($password, 'blight') !== false) )
        {                return false;
        }
                
        $db = blightDB();
        $sessid = GWF_Session::getSessSID();        $query = "SELECT 1 FROM (SELECT password FROM blight WHERE sessid=$sessid) b WHERE password='$password'";
        return $db->queryFirst($query) !== false;
}
 
 #####################
### Not vuln util ###
#####################
/**
 * Increase the attempt counter. * @return true|false
 */
function blightCountUp()
{
        $db = blightDB();        $sessid = GWF_Session::getSessSID();
        $query = "UPDATE blight SET attemp=attemp+1 WHERE sessid=$sessid";
        return $db->queryWrite($query);
}
 /**
 * Set the attempt counter.
 * @return true|false
 */
function blightSetAttempt($attempt){
        $db = blightDB();
        $attempt = (int)$attempt;
        $sessid = GWF_Session::getSessSID();
        $query = "UPDATE blight SET attemp=$attempt WHERE sessid=$sessid";        return $db->queryWrite($query);
}
 
/**
 * Reset counter and password. * @return true|false
 */
function blightReset($consec=true)
{
        if ($consec)        {
                # Reset consecutive success counter.
                blightFailed();
        }
                # Take a timestamp.
        GWF_Session::set('BLIGHT2_TIME_START', time());
        
        # Generate a new hash.
        $db = blightDB();        $sessid = GWF_Session::getSessSID();
        $hash = GWF_Random::randomKey(32, 'ABCDEF0123456789');
        $query = "REPLACE INTO blight VALUES($sessid, '$hash', 0)";
        return $db->queryWrite($query);
} 
/**
 * Get the attempt counter.
 * @return int
 */function blightAttemp()
{
        $db = blightDB();
        $sessid = GWF_Session::getSessSID();
        $query = "SELECT attemp FROM blight WHERE sessid=$sessid";        if (false === ($result = $db->queryFirst($query)))
        {
                return -1;
        }
        return (int)$result['attemp'];}
 
/**
 * Get the correct solution.
 * This counts as one attempt. * @return string|false
 */
function blightGetHash()
{
        blightCountUp(); # 1 attempt        
        $db = blightDB();
        $sessid = GWF_Session::getSessSID();
        $query = "SELECT password FROM blight WHERE sessid=$sessid";
        if (false === ($result = $db->queryFirst($query)))        {
                return false;
        }
        return $result['password'];
} 
/**
 * Init the challenge.
 * @return void
 */function blightInit()
{
        $attempt = blightAttemp();
        if ($attempt < 0)
        {                blightReset(false);
        }
}
 
############## NEW ###
###########
/**
 * You successfully hacked it one time.
 * But return false if you need a few more consecutive hacks to solve the chall. * @return true|false
 */
function blightSolved()
{
        $solvecount = GWF_Session::getOrDefault('BLIGHT2_CONSECUTIVE', 0);        $solvecount++;
        
        blightReset(false);
        
        if ($solvecount >= BLIGHT2_CONSEC)        {
                GWF_Session::remove('BLIGHT2_CONSECUTIVE');
                return true;
        }
                GWF_Session::set('BLIGHT2_CONSECUTIVE', $solvecount);
        return false;
}
 
/** * Reset consecutive success counter.
 * @return void
 */
function blightFailed()
{        GWF_Session::set('BLIGHT2_CONSECUTIVE', 0);
}
 
/**
 * Check if you were too slow. * @return true|false
 */
function blightTimeout()
{
        if (false === ($start = GWF_Session::getOrDefault('BLIGHT2_TIME_START', false)))        {
                return true;
        }
        else
        {                return (time() - $start) > BLIGHT2_TIME;
        }
}
?>