hash.py

import re
import socket
import subprocess

s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
s.connect(("ctfchallenges.ritsec.club", 8080))

data = s.recv(1024)
if data == "":
    exit(1)

files = data.decode().split('\n')[-2]
hash = s.recv(1024).decode()

print("Received:", files, '\n', hash)

start = len("However... We have a theory that the passwords might come from ")
filenames = re.split(', | or ', files[start:])
print(filenames)

def crack(hash):
    with open("hash.txt", 'w') as fd:
        fd.write(hash)

    for file in filenames:
        print("trying file", file)
        print(subprocess.run(["john", "--wordlist=" + file, "hash.txt"]))
        john = subprocess.Popen(["john", "--show", "hash.txt"], stdout=subprocess.PIPE)
        stdout, _ = john.communicate()                                                       
        if '0 password hashes cracked' not in stdout.decode():                               
            pw = stdout[2:].split(b'\n')[0]                                                  
            print("success:", pw)                                                            
            s.sendall(pw + b'\n')                                                            
            return                                                                           
        else:                                                                                
            print("failure:", stdout)                                                        
    print("all files failed :(")                                                             
    s.close()                                                                                
    exit(1)                                                                                  
                                                                                             
                                                                                             
while 1:                                                                                     
    crack(hash)                                                                              
    hash = s.recv(1024)
    if not hash:
        break
    print(hash)

print("Connection closed.")
s.close()