def main():
with open("6.txt", "r") as f:
ciphertext_b64 = f.read().replace("\n", "")
ciphertext = base64_to_bytearray(ciphertext_b64)
key = break_repeating_key_xor(ciphertext)
print("challenge 1.6 key is: %s" % bytearray(key))
message = encrypt_repeating_key(ciphertext, key)
def main():
test_aes_ecb()
with open("7.txt", "r") as f: ciphertext_b64 = f.read().replace("\n", "")
ciphertext_bt = base64_to_bytearray(ciphertext_b64)
key = string_to_bytearray("YELLOW SUBMARINE")
message = decrypt_aes_128_ecb(ciphertext_bt, key)
assert b"I'm back and I'm ringin' the bell" in message
print("challenge 1.7 completed.")
def cbc_encryption_oracle():
messages_encrypted = []
for message in messages:
message_to_encrypt = base64_to_bytearray(message)
message_to_encrypt_padded = pad_to_mod_16(message_to_encrypt)
ciphertext = encrypt_aes_cbc(message_to_encrypt_padded, ORACLE_KEY, ORACLE_IV)
messages_encrypted.append(ciphertext)
return messages_encrypted
def main():
plaintext_b64 = "VGhhdCdzIHdoeSBJIGZvdW5kIHlvdSBkb24ndCBwbGF5IGFyb3VuZCB3aXRoIHRoZSBGdW5reSBDb2xkIE1lZGluYQ=="
plaintext = str(base64_to_bytearray(plaintext_b64))
ciphertext = ORACLE_KEY.encrypt(plaintext)
found_plaintext = attack_parity_oracle(ciphertext, ORACLE_KEY.e, ORACLE_KEY.N)
if found_plaintext == plaintext:
print("challenge 5.46 completed.")
else:
print("challenge 5.46 failed.")
def main():
test_aes_ctr()
ciphertext_b64 = 'L77na/nrFsKvynd6HzOoG7GHTLXsTVu9qvY/2syLXzhPweyyMTJULu/6/kXX0KSvoOLSFQ=='
ciphertext_bt = base64_to_bytearray(ciphertext_b64)
key = string_to_bytearray("YELLOW SUBMARINE")
nonce = bytearray([0] * 8)
message = decrypt_aes_ctr(ciphertext_bt, key, nonce)
#print message
assert b"VIP Let's kick it" in message
print("challenge 3.18 completed.")
def main():
test_aes_cbc()
with open("10.txt", "r") as f:
ciphertext_b64 = f.read().replace("\n", "")
ciphertext_bt = base64_to_bytearray(ciphertext_b64)
key = string_to_bytearray("YELLOW SUBMARINE")
iv = bytearray([0] * 16)
message = decrypt_aes_cbc(ciphertext_bt, key, iv)
assert b"I'm back and I'm ringin' the bell" in message
print("challenge 2.10 completed.")
from aes_ecb_mode import encrypt_aes_128_ecb
from pkcs7_padding import pad_to_mod_16
from ecb_cbc_detection_oracle import detection_oracle
import byte_at_a_time_ecb_decryption_simple as byte_at_a_time_simple
from utils import chunks_of_bytearray
from itertools import groupby
oracle_key = crypto_random_bytes(16)
secret_b64_string = '''
Um9sbGluJyBpbiBteSA1LjAKV2l0aCBteSByYWctdG9wIGRvd24gc28gbXkg
aGFpciBjYW4gYmxvdwpUaGUgZ2lybGllcyBvbiBzdGFuZGJ5IHdhdmluZyBq
dXN0IHRvIHNheSBoaQpEaWQgeW91IHN0b3A/IE5vLCBJIGp1c3QgZHJvdmUg
YnkK
'''
secret = base64_to_bytearray(secret_b64_string)
padding = crypto_random_bytes(random_integer(1, 30))
def encryption_oracle_ecb(plaintext):
to_encrypt = pad_to_mod_16(padding + plaintext + secret)
return encrypt_aes_128_ecb(to_encrypt, oracle_key)
def _check_magic_blocks_number(magic, ct, block_size):
blocks = chunks_of_bytearray(ct, block_size)
repeating_blocks_grouped = [list(j) for i, j in groupby(blocks)]
repeating_blocks_sizes = [len(i) for i in repeating_blocks_grouped]
# padding is multiple of block_size
if magic in repeating_blocks_sizes:
for xor_cipher in xor_ciphers:
score, message, key = break_xor_cipher(xor_cipher,
alpha_and_printable_heuristic)
key_used.append(key)
return key_used
BLOCK_SIZE = 16
KEY = crypto_random_bytes(BLOCK_SIZE)
NONCE = bytearray([0] * 8)
with open('20.txt', 'r') as f:
lines = f.readlines()
messages_b64 = [line.replace("\n", "") for line in lines]
messages = [base64_to_bytearray(i) for i in messages_b64]
ciphertexts = [encrypt_aes_ctr(i, KEY, NONCE) for i in messages]
key_stream_length = max([len(i) for i in ciphertexts])
key_stream = [0] * key_stream_length
def main():
key_stream = break_ctr(ciphertexts)
messages_decrypted = [xor_diff_lengths(key_stream, i) for i in ciphertexts]
# for ix, m in enumerate(messages_decrypted):
# print(ix, m)
message_corrected = b"You think you're ruffer, then suffer the consequences"