def check_q2c(module_path):
try:
module = import_module(module_path)
signature = module.forge_signature()
except Exception as e:
error('Exception forging a signature with {}', module_path)
traceback.print_exc()
return False
if not isinstance(signature, ServerResponse):
error('Signature should be a ServerResponse but is a {}',
type(signature))
return False
try:
if not ATM().verify_server_approval(signature):
error('Verification does not pass with signature from {}',
module_path)
except Exception as e:
error('Exception while running the verification on response from {}',
module_path)
traceback.print_exc()
return False
return True
def extract_PIN(encrypted_PIN): atm = ATM() all_pin_combinations = itertools.product([i for i in range(10)], repeat=4) for i in range(10**4): temp_combination_arr = all_pin_combinations.next() temp_combination_str = "".join(str(digit) for digit in temp_combination_arr) temp_combination_int = int(temp_combination_str) if atm.rsa_pin.encrypt(temp_combination_int,None)[0] == encrypted_PIN: return int(temp_combination_int)
def extract_PIN(encrypted_PIN):
"""Extracts the original PIN string from an encrypted PIN."""
# Return an integer.
#raise NotImplementedError()
atm_try = ATM()
for i in range(0, 11000):
pin = getattr(atm_try, 'encrypt_PIN')
if pin(i) == encrypted_PIN:
return i
return -1
def extract_PIN(encrypted_PIN):
"""Extracts the original PIN string from an encrypted PIN."""
# Return an integer.
# Brute force all the options
atm = ATM()
for pin in xrange(1000, 10000):
msg = atm.encrypt_PIN(pin)
if msg == encrypted_PIN:
return pin
def extract_PIN(encrypted_PIN):
"""Extracts the original PIN string from an encrypted PIN."""
# Return an integer.
original_PIN = None
possible_PIN_codes = create_all_possible_PIN()
atm = ATM()
for p in possible_PIN_codes:
int_PIN = convert_digits_array_to_int(p)
current_encrypted_PIN = atm.encrypt_PIN(int_PIN)
if current_encrypted_PIN == encrypted_PIN:
original_PIN = int_PIN
break
return original_PIN
def extract_credit_card(encrypted_credit_card):
"""Extracts a credit card number string from its ciphertext."""
# Return an integer.
#raise NotImplementedError()
atm_try = ATM()
credit_num = getattr(atm_try, 'encrypt_credit_card')
pin = int(round(encrypted_credit_card**(1.0 / 3)))
pinT = pin**3
encr_credit_num = credit_num(pin)
if (pinT == encrypted_credit_card
) and encr_credit_num == encrypted_credit_card:
real_creadit_card = pin
return real_creadit_card
def extract_credit_card(encrypted_credit_card):
"""Extracts a credit card number string from its ciphertext."""
# Return an integer.
# This solution is correct only for small e
import math
atm = ATM()
card_key = atm.rsa_card
n = card_key.n
e = card_key.e
return int(
math.ceil((10**(math.log(encrypted_credit_card, 10) / e)))
) # This is never an int, so need to take or floor or ceiling value. ceiling was decided
def check_q2b(module_path):
return check_extraction(module_path, 'extract_credit_card', 'credit card',
123456789,
ATM().encrypt_credit_card, (int, long))
def check_q2a(module_path):
return check_extraction(module_path, 'extract_PIN', 'PIN', 1234,
ATM().encrypt_PIN, (int, long))
def forge_signature():
atm_try = ATM()
number = getattr(atm_try, 'encrypt_number')
approval = atm_try.CODE_APPROVAL
rsa_card = atm_try.rsa_card
return ServerResponse(approval, number(rsa_card, approval))
def extract_PIN(encrypted_PIN):
item = ATM()
for i in range(10000):
if (item.encrypt_PIN(i) == encrypted_PIN):
return i