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-rw-r--r--youtube_dl/aes.py43
1 files changed, 38 insertions, 5 deletions
diff --git a/youtube_dl/aes.py b/youtube_dl/aes.py
index c5bb3c4ef..a94a41079 100644
--- a/youtube_dl/aes.py
+++ b/youtube_dl/aes.py
@@ -1,13 +1,25 @@
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
+def pkcs7_padding(data):
+ """
+ PKCS#7 padding
+
+ @param {int[]} data cleartext
+ @returns {int[]} padding data
+ """
+
+ remaining_length = BLOCK_SIZE_BYTES - len(data) % BLOCK_SIZE_BYTES
+ return data + [remaining_length] * remaining_length
+
+
def aes_ctr_decrypt(data, key, counter):
"""
Decrypt with aes in counter mode
@@ -76,8 +88,7 @@ def aes_cbc_encrypt(data, key, iv):
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
+ block = pkcs7_padding(block)
mixed_block = xor(block, previous_cipher_block)
encrypted_block = aes_encrypt(mixed_block, expanded_key)
@@ -88,6 +99,28 @@ def aes_cbc_encrypt(data, key, iv):
return encrypted_data
+def aes_ecb_encrypt(data, key):
+ """
+ Encrypt with aes in ECB mode. Using PKCS#7 padding
+
+ @param {int[]} data cleartext
+ @param {int[]} key 16/24/32-Byte cipher key
+ @returns {int[]} encrypted data
+ """
+ expanded_key = key_expansion(key)
+ block_count = int(ceil(float(len(data)) / BLOCK_SIZE_BYTES))
+
+ encrypted_data = []
+ for i in range(block_count):
+ block = data[i * BLOCK_SIZE_BYTES: (i + 1) * BLOCK_SIZE_BYTES]
+ block = pkcs7_padding(block)
+
+ encrypted_block = aes_encrypt(block, expanded_key)
+ encrypted_data += encrypted_block
+
+ return encrypted_data
+
+
def key_expansion(data):
"""
Generate key schedule
@@ -180,7 +213,7 @@ def aes_decrypt_text(data, password, key_size_bytes):
"""
NONCE_LENGTH_BYTES = 8
- data = bytes_to_intlist(base64.b64decode(data.encode('utf-8')))
+ 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))
@@ -303,7 +336,7 @@ def xor(data1, data2):
def rijndael_mul(a, b):
- if(a == 0 or b == 0):
+ if (a == 0 or b == 0):
return 0
return RIJNDAEL_EXP_TABLE[(RIJNDAEL_LOG_TABLE[a] + RIJNDAEL_LOG_TABLE[b]) % 0xFF]