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@fuwwy
Created Aug 5, 2022
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StudSec CTF Token Challenge Cracker
import logging # Have to use logging to print inside signals
import time
import fcntl
import os
import signal
from randcrack import RandCrack
import sys
dirname = "/tmp/"
filename = "py-log1376543.txt"
rc = RandCrack()
is_ready = False
queue = []
def handler():
last_line = read_file()[-1]
logging.info(f"New passwd change: {last_line}")
if is_ready:
logging.info(f'Next code prediction: {"".join(rc.predict_choice("0123456789abcdef") for _ in range(10)).upper()}')
else:
queue.append(last_line)
def main():
global is_ready
start_file_listener(filename, handler)
lines = read_file()
randints = lines[1:701]
codes = lines[704:]
start_timer("Seeding with 624 initial ints...")
for _ in range(624):
rc.submit(int(randints.pop(0)));
start_timer(f"Feeding the last {len(randints)} ints...")
while len(randints) > 0:
real = int(randints.pop(0))
pred = rc.predict_randint(0, 4294967294)
if not real == pred:
sys.exit(f"Something went wrong while feeding ints. Real = {real}, Pred = {pred}")
total_len = len(codes)
logging.info(f"Feeding all the {total_len} previous codes.")
start_timer(f"This will take a while, go grab some coffee... (Approx {2500 * total_len / 1e+6} sec)")
while len(codes) > 0:
prg = (total_len - len(codes)) / total_len * 100
if (prg > 0 and prg % 5 == 0):
logging.info(str(round(prg)) + '%...')
for _ in range(10):
#rc.predict_choice('0123456789abcdef')
rc.predict_randbelow(16)
codes.pop(0)
handle_queue()
reset_timer()
logging.info(f'Next code prediction: {"".join(rc.predict_choice("0123456789abcdef") for _ in range(10)).upper()}')
is_ready = True
def handle_queue():
while len(queue) > 0:
for _ in range(10):
rc.predict_choice('0123456789abcdef')
queue.pop(0)
if len(queue) > 0:
handle_queue()
#for pos in range(0, 700):
# starting = randints[int(pos)]
# rc = RandCrack()
# for pos2 in range(int(pos), min(int(pos)+624, 700)):
# rc.submit(int(randints[pos2]));
# if rc.predict_randint(0, 4294967294) == randints[min(int(pos)+625, 699)]:
# print("Pog?")
# else:
# print("F")
def read_file():
with open(dirname + filename, "r") as f:
return f.readlines()
prevLastModifiedTime = 0
def start_file_listener(filename, handler):
def check_changes(*_):
global prevLastModifiedTime
lastModifiedTime = os.stat(filename).st_mtime
if lastModifiedTime != prevLastModifiedTime:
prevLastModifiedTime = lastModifiedTime
handler()
signal.signal(signal.SIGIO, check_changes)
fd = os.open(dirname, os.O_RDONLY)
fcntl.fcntl(fd, fcntl.F_SETSIG, 0)
fcntl.fcntl(fd, fcntl.F_NOTIFY, fcntl.DN_MODIFY | fcntl.DN_CREATE | fcntl.DN_MULTISHOT)
start_time = 0
def start_timer(line):
global start_time
if (start_time > 0):
reset_timer()
start_time = time.time()
if line:
logging.info(line)
def reset_timer():
global start_time
logging.info("Took {}ms.".format(round((time.time() - start_time) * 1000)))
start_time = 0
logging.basicConfig(level=logging.NOTSET, format='%(message)s')
main()
while True:
time.sleep(10000)
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