-__all__ = ['aes_encrypt', 'key_expansion', 'aes_ctr_decrypt', 'aes_cbc_decrypt', 'aes_decrypt_text']
+from __future__ import unicode_literals
-import base64
from math import ceil
+from .compat import compat_b64decode
from .utils import bytes_to_intlist, intlist_to_bytes
BLOCK_SIZE_BYTES = 16
decrypted_data = []
for i in range(block_count):
counter_block = counter.next_value()
- block = data[i *BLOCK_SIZE_BYTES: (i +1) *BLOCK_SIZE_BYTES]
- block += [0] *(BLOCK_SIZE_BYTES - len(block))
+ block = data[i * BLOCK_SIZE_BYTES: (i + 1) * BLOCK_SIZE_BYTES]
+ block += [0] * (BLOCK_SIZE_BYTES - len(block))
cipher_counter_block = aes_encrypt(counter_block, expanded_key)
decrypted_data += xor(block, cipher_counter_block)
decrypted_data = []
previous_cipher_block = iv
for i in range(block_count):
- block = data[i *BLOCK_SIZE_BYTES: (i +1) *BLOCK_SIZE_BYTES]
- block += [0] *(BLOCK_SIZE_BYTES - len(block))
+ block = data[i * BLOCK_SIZE_BYTES: (i + 1) * BLOCK_SIZE_BYTES]
+ block += [0] * (BLOCK_SIZE_BYTES - len(block))
decrypted_block = aes_decrypt(block, expanded_key)
decrypted_data += xor(decrypted_block, previous_cipher_block)
return decrypted_data
+def aes_cbc_encrypt(data, key, iv):
+ """
+ Encrypt with aes in CBC mode. Using PKCS#7 padding
+
+ @param {int[]} data cleartext
+ @param {int[]} key 16/24/32-Byte cipher key
+ @param {int[]} iv 16-Byte IV
+ @returns {int[]} encrypted data
+ """
+ expanded_key = key_expansion(key)
+ block_count = int(ceil(float(len(data)) / BLOCK_SIZE_BYTES))
+
+ encrypted_data = []
+ previous_cipher_block = iv
+ for i in range(block_count):
+ block = data[i * BLOCK_SIZE_BYTES: (i + 1) * BLOCK_SIZE_BYTES]
+ remaining_length = BLOCK_SIZE_BYTES - len(block)
+ block += [remaining_length] * remaining_length
+ mixed_block = xor(block, previous_cipher_block)
+
+ encrypted_block = aes_encrypt(mixed_block, expanded_key)
+ encrypted_data += encrypted_block
+
+ previous_cipher_block = encrypted_block
+
+ return encrypted_data
+
+
def key_expansion(data):
"""
Generate key schedule
temp = data[-4:]
temp = key_schedule_core(temp, rcon_iteration)
rcon_iteration += 1
- data += xor(temp, data[-key_size_bytes: 4 -key_size_bytes])
+ data += xor(temp, data[-key_size_bytes: 4 - key_size_bytes])
for _ in range(3):
temp = data[-4:]
- data += xor(temp, data[-key_size_bytes: 4 -key_size_bytes])
+ data += xor(temp, data[-key_size_bytes: 4 - key_size_bytes])
if key_size_bytes == 32:
temp = data[-4:]
temp = sub_bytes(temp)
- data += xor(temp, data[-key_size_bytes: 4 -key_size_bytes])
+ data += xor(temp, data[-key_size_bytes: 4 - key_size_bytes])
- for _ in range(3 if key_size_bytes == 32 else 2 if key_size_bytes == 24 else 0):
+ for _ in range(3 if key_size_bytes == 32 else 2 if key_size_bytes == 24 else 0):
temp = data[-4:]
- data += xor(temp, data[-key_size_bytes: 4 -key_size_bytes])
+ data += xor(temp, data[-key_size_bytes: 4 - key_size_bytes])
data = data[:expanded_key_size_bytes]
return data
rounds = len(expanded_key) // BLOCK_SIZE_BYTES - 1
data = xor(data, expanded_key[:BLOCK_SIZE_BYTES])
- for i in range(1, rounds +1):
+ for i in range(1, rounds + 1):
data = sub_bytes(data)
data = shift_rows(data)
if i != rounds:
data = mix_columns(data)
- data = xor(data, expanded_key[i *BLOCK_SIZE_BYTES: (i +1) *BLOCK_SIZE_BYTES])
+ data = xor(data, expanded_key[i * BLOCK_SIZE_BYTES: (i + 1) * BLOCK_SIZE_BYTES])
return data
rounds = len(expanded_key) // BLOCK_SIZE_BYTES - 1
for i in range(rounds, 0, -1):
- data = xor(data, expanded_key[i *BLOCK_SIZE_BYTES: (i +1) *BLOCK_SIZE_BYTES])
+ data = xor(data, expanded_key[i * BLOCK_SIZE_BYTES: (i + 1) * BLOCK_SIZE_BYTES])
if i != rounds:
data = mix_columns_inv(data)
data = shift_rows_inv(data)
"""
NONCE_LENGTH_BYTES = 8
- data = bytes_to_intlist(base64.b64decode(data))
+ data = bytes_to_intlist(compat_b64decode(data))
password = bytes_to_intlist(password.encode('utf-8'))
- key = password[:key_size_bytes] + [0] *(key_size_bytes - len(password))
+ key = password[:key_size_bytes] + [0] * (key_size_bytes - len(password))
key = aes_encrypt(key[:BLOCK_SIZE_BYTES], key_expansion(key)) * (key_size_bytes // BLOCK_SIZE_BYTES)
nonce = data[:NONCE_LENGTH_BYTES]
cipher = data[NONCE_LENGTH_BYTES:]
- class Counter:
- __value = nonce + [0] *(BLOCK_SIZE_BYTES - NONCE_LENGTH_BYTES)
+ class Counter(object):
+ __value = nonce + [0] * (BLOCK_SIZE_BYTES - NONCE_LENGTH_BYTES)
def next_value(self):
temp = self.__value
return plaintext
+
RCON = (0x8d, 0x01, 0x02, 0x04, 0x08, 0x10, 0x20, 0x40, 0x80, 0x1b, 0x36)
SBOX = (0x63, 0x7C, 0x77, 0x7B, 0xF2, 0x6B, 0x6F, 0xC5, 0x30, 0x01, 0x67, 0x2B, 0xFE, 0xD7, 0xAB, 0x76,
0xCA, 0x82, 0xC9, 0x7D, 0xFA, 0x59, 0x47, 0xF0, 0xAD, 0xD4, 0xA2, 0xAF, 0x9C, 0xA4, 0x72, 0xC0,
def xor(data1, data2):
- return [x^y for x, y in zip(data1, data2)]
+ return [x ^ y for x, y in zip(data1, data2)]
def rijndael_mul(a, b):
def mix_columns(data, matrix=MIX_COLUMN_MATRIX):
data_mixed = []
for i in range(4):
- column = data[i *4: (i +1) *4]
+ column = data[i * 4: (i + 1) * 4]
data_mixed += mix_column(column, matrix)
return data_mixed
def inc(data):
data = data[:] # copy
- for i in range(len(data) -1, -1, -1):
+ for i in range(len(data) - 1, -1, -1):
if data[i] == 255:
data[i] = 0
else:
data[i] = data[i] + 1
break
return data
+
+
+__all__ = ['aes_encrypt', 'key_expansion', 'aes_ctr_decrypt', 'aes_cbc_decrypt', 'aes_decrypt_text']
projects / youtube-dl / blobdiff