def test_number_bits_changed_M():
aes = AES.AES(key)
ciphertext = aes.encrypt_block(message)
modifiedbits = [0] * 128
for i in range(128):
modifiedMessage = int_to_bytes(bytes_to_int(message) ^ (1 << i), 16)
ci = aes.encrypt_block(modifiedMessage)
modifiedbits[count_modified_bits(ciphertext, ci)] += 1
print(modifiedbits)
def test_no_MixColumns():
aes = AESMixColumns.AES(key)
ciphertext = aes.encrypt_block(message)
for i in range(4):
ci = aes.encrypt_block(
int_to_bytes(bytes_to_int(message) ^ (1 << i * 32), 16))
print("Original ciphertext:")
print_block(ciphertext)
print("1 bit modified:")
print_block(ci)
print()
def decryptSet(preMasterKeys, coreNum):
print("set", coreNum, "contains", len(preMasterKeys), "preMasterKeys")
cipher = open("2019_09_25_17_02_22_joan.marc.pastor.puerta_trasera.enc",
'rb').read()
for preKey in preMasterKeys:
preKeyInBytes = int_to_bytes(preKey, 16)
hashkey = bytes_to_int(hashlib.sha256(preKeyInBytes).digest())
KEY = int_to_bytes(hashkey >> 128, 16)
IV = int_to_bytes(hashkey & 0xFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF,
16) # 32x F
aes = AES.new(KEY, AES.MODE_CBC, IV)
paddedMessage = aes.decrypt(cipher)
try:
message = unpad(paddedMessage, AES.block_size,
style='pkcs7') #Rises error if wrong format
print("possible preMasterKey: ", hex(preKey))
open('out/' + hex(preKey).replace("0x", "") + '.mp4',
'wb').write(message)
except:
pass
print("Core", coreNum, "finished")
def test_no_ByteSub():
aes = AESByteSub.AES(key)
ciphertext = aes.encrypt_block(message)
compleixPropietat = True
for i in range(128):
for j in range(128):
ci = aes.encrypt_block(
int_to_bytes(bytes_to_int(message) ^ (1 << i), 16))
cj = aes.encrypt_block(
int_to_bytes(bytes_to_int(message) ^ (1 << j), 16))
cij = aes.encrypt_block(
int_to_bytes(
bytes_to_int(message) ^ ((1 << i) ^ (1 << j)), 16))
if (bytes_to_int(ciphertext) !=
bytes_to_int(ci) ^ bytes_to_int(cj) ^ bytes_to_int(cij)):
compleixPropietat = False
if (compleixPropietat):
print("La propietat C = Ci XOR Cj XOR Cij per a tot i, j es compleix.")
else:
print(
"La propietat C = Ci XOR Cj XOR Cij per a tot i, j no es compleix."
)
def test_position_of_bits_changed_M():
aes = AES.AES(key)
c = aes.encrypt_block(message)
modifiedbits = [0] * 128
sum = 0
for i in range(128):
modifiedMessage = int_to_bytes(bytes_to_int(message) ^ (1 << i), 16)
ci = aes.encrypt_block(modifiedMessage)
for j in range(128):
bitc = (bytes_to_int(c) >> j) % 2
bitci = (bytes_to_int(ci) >> j) % 2
if (bitc != bitci):
modifiedbits[j] += 1
sum += 1
print(modifiedbits)
print("mean = ", sum / 128)