One script solve all crackme2000 in defcon ctf quals 2017

crackme2000_solver.py

#!/usr/bin/env python2

import os, sys
import string
import subprocess

prefix = 'enlightenment'  # change this to solve other crackme2000 challenges

def bf(bp):
    flag = ''
    while True:
        for i in string.printable:
            p = subprocess.Popen(bp, stdin=subprocess.PIPE, stdout=subprocess.PIPE, stderr=subprocess.PIPE)
            stdout, stderr = p.communicate(flag + i)
            exit_code = p.returncode
            print repr(flag), i, exit_code
            if exit_code != len(flag)+1 or stderr:
                flag += i
                print 'found', i
                print 'flag', repr(flag)
                if exit_code == 0:
                    return flag
                break
        else:
            raise Exception('flag not found')
        if flag.endswith('00000000000000') or len(flag) > 64:
            raise Exception('error flag: %s' % bp)
    return flag

# bf(prefix + '_dist/fe6582d661a0a5dcfd63d6fc8e3302b97b0341df166978dffd022a0bc9f24d86')
# sys.exit()

def handle(x):
    print 'handling', x
    i = x
    if os.path.exists('ans/%s' % i): return
    flag = bf(prefix + '_dist/%s' % i)
    with open('ans/%s' % i, 'wb') as f:
        f.write(flag)

def worker():
    while True:
        item = q.get()
        if not item:
            return
        thread = Thread(target=handle, args=(item,))
        thread.start()
        thread.join(30)
        # handle(item)
        q.task_done()

from queue import Queue
from threading import Thread

q = Queue()
for i in range(4):
     t = Thread(target=worker)
     t.daemon = True
     t.start()

targets =  filter(lambda x:len(x) == 64, os.listdir(prefix + '_dist'))
for item in targets:
    q.put(item)

q.join()       # block until all tasks are done