R2con CTF 2020 - Cyber Lock Solution

main.py

#!/usr/bin/env python3

import hashlib
import string

correct_hashes = [
    "D9259A378FC0EA75C1828369059854DEF76F91CABD01B56EF548C7ABA6441D59DD2DB9E51BD70C457179A123D53138F88132B29C691A9671F6C80E41E7D682A4",
    "3F675784DABBC1330806CB4D5FE67860C25E103B75EB7B22821B2D75264B60C4D2E042A1726E1B85E3936A2A95E835E92FEFAC2C2E34A249109D98AED3962C71",
    "BD605F0A10170EC1F7610BCF696C518AAB31C235CCF47866A71C332368BFE8B7E9FE4E3907B3CD37F111B40EEFFE89287C25033A41369A3236751474AD522537",
    "B8CA8A22501EAB44AD44E6EB2F87791CA69955BFFC025988418866BDD8A1EAABA97F630A705D68B26370E49DAD9DE65AB478117C4289FFC240A8C85308D116A1",
    "0694F2776E101C72092994B2F125973CBD3A608B3BA17CF8795DDDEEDE6773E0DE8D832EAE4EE3FF8C748FD6BDBC1BF843081CC6AEEFB09B1C908AD484382884",
    "F9B4F710E8ADC5D4A32779A865396B019A630E2B1DB475F0F1656BC195ED2E0171932C9629DE5417F5C2D96FECC4B89107C9E28477513F98D5147391DF374C3C",
    "B8CA8A22501EAB44AD44E6EB2F87791CA69955BFFC025988418866BDD8A1EAABA97F630A705D68B26370E49DAD9DE65AB478117C4289FFC240A8C85308D116A1",
    "7280E46538FE2158921FA20E7A835E9F4900E8AFDA73E1D1EE03472E0B34D59AC28ABE964652B6EC8DF1B44D3F1B90A7684D470A191BB446FB2149918E69DE38",
    "F08DF5E5DFDACE8892F03B4475263D72D6999DCC499C741028935D7D167222086F5FB63C793C20BA02E56AB74E901B1E66D178206E91B469F6055E63EE824D7F",
    "9D9A2B793485D2ADF818DB5DF1D97CD1072F826845940780ECA50B623F8D931DC9533AF77DF2B811645B8B852670188A17736E8A536F672D5639EA40F2D1FC40",
    "4AC1807EC58C1BD56D177E3F409FBD0FBCDE7D97F9F8A71469FD92817BB866B4D71A0DF10EB501AF6CE4439861E46B89473555B08874CEBA33312AD3495E84F2",
    "0694F2776E101C72092994B2F125973CBD3A608B3BA17CF8795DDDEEDE6773E0DE8D832EAE4EE3FF8C748FD6BDBC1BF843081CC6AEEFB09B1C908AD484382884"
]

print("[INFO] we have", len(correct_hashes), "hashy boys")

suffix = "_3_r2con2020"
alphabet = list(string.ascii_letters)

def sha256_hash_string(string):
    """
    Return a SHA-256 hash of the given string
    """
    return hashlib.sha256(string.encode('utf-8')).hexdigest()

def sha512_hash_string(string):
    """
    Return a SHA-256 hash of the given string
    """
    return hashlib.sha512(string.encode('utf-8')).hexdigest()

solution = ""

for index, hash in enumerate(correct_hashes):

    print(f"[INFO] Solving has {index}")

    for a in alphabet:
        sha256_hash_prefix = sha256_hash_string(a)
        sha256_hash_prefix = sha256_hash_prefix.upper()

        concatinated_string = sha256_hash_prefix + suffix
        sha512_complete_hash = sha512_hash_string(concatinated_string)

        if (sha512_complete_hash.upper() == correct_hashes[index]):
            print(f"\tMatch found for {sha512_complete_hash}!")
            print(f"\tKey {index} char is {a}, key is: {sha256_hash_prefix}")

            solution += sha256_hash_prefix

# Verify the length matches 12 sha256 hashes
if len(solution) == (64*12):
    print(f"[INFO] Complete solution:\n{solution}")