tutorial-violent/crack/crack.py

66 lines
1.6 KiB
Python

import re
import sys
from passlib.hash import sha512_crypt
DEF_ROUNDS = 5000
def parse_crypt_line(cr_line: str):
p_cr_pass = cr_line.split("$", 3)
if len(p_cr_pass) < 3:
return None, None, None
_, alg, salt, passwd = p_cr_pass
return alg, salt, passwd
def brute_passwd(dict_file, cr_line):
alg, salt, passwd = parse_crypt_line(cr_line)
if not passwd:
return None
r_match = re.match(r".*rounds=(\d*)", salt)
rounds = r_match.group(1) if r_match else DEF_ROUNDS
with open(dict_file, 'r') as df:
for line in df.readlines():
open_pass = line.strip()
exp_pass = sha512_crypt.hash(open_pass, salt=salt, rounds=rounds)
if exp_pass == cr_line:
return open_pass
return None
def parse_shadow(shadow_file):
result = dict()
with open(shadow_file, 'r') as sf:
for line in sf.readlines():
p_line = line.split(":")
if len(p_line) < 2:
continue
user, cr_pass = p_line[:2]
if not all(parse_crypt_line(cr_pass)):
continue
result[user] = cr_pass
return result
def main():
if len(sys.argv) != 3:
print(f"Usage: {sys.argv[0]} <shadow_file> <dictionary>")
exit(0)
shadow = sys.argv[1]
dictionary = sys.argv[2]
shadow_data = parse_shadow(shadow)
for user, cr_pass in shadow_data.items():
found_pass = brute_passwd(dictionary, cr_pass)
if found_pass:
print(f"[+] Found password for {user}: {found_pass}")
continue
if __name__ == "__main__":
main()