from math import ceil
from .compat import compat_ord
-from .dependencies import Cryptodome_AES
+from .dependencies import Cryptodome
from .utils import bytes_to_intlist, intlist_to_bytes
-if Cryptodome_AES:
+if Cryptodome.AES:
def aes_cbc_decrypt_bytes(data, key, iv):
""" Decrypt bytes with AES-CBC using pycryptodome """
- return Cryptodome_AES.new(key, Cryptodome_AES.MODE_CBC, iv).decrypt(data)
+ return Cryptodome.AES.new(key, Cryptodome.AES.MODE_CBC, iv).decrypt(data)
def aes_gcm_decrypt_and_verify_bytes(data, key, tag, nonce):
""" Decrypt bytes with AES-GCM using pycryptodome """
- return Cryptodome_AES.new(key, Cryptodome_AES.MODE_GCM, nonce).decrypt_and_verify(data, tag)
+ return Cryptodome.AES.new(key, Cryptodome.AES.MODE_GCM, nonce).decrypt_and_verify(data, tag)
else:
def aes_cbc_decrypt_bytes(data, key, iv):
return intlist_to_bytes(aes_cbc_encrypt(*map(bytes_to_intlist, (data, key, iv)), **kwargs))
+BLOCK_SIZE_BYTES = 16
+
+
def unpad_pkcs7(data):
return data[:-compat_ord(data[-1])]
-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 pad_block(block, padding_mode):
def aes_ecb_encrypt(data, key, iv=None):
"""
- Encrypt with aes in ECB mode
+ Encrypt with aes in ECB mode. Using PKCS#7 padding
@param {int[]} data cleartext
@param {int[]} key 16/24/32-Byte cipher key
encrypted_data = []
for i in range(block_count):
block = data[i * BLOCK_SIZE_BYTES: (i + 1) * BLOCK_SIZE_BYTES]
- encrypted_data += aes_encrypt(block, expanded_key)
- encrypted_data = encrypted_data[:len(data)]
+ encrypted_data += aes_encrypt(pkcs7_padding(block), expanded_key)
return encrypted_data
'key_expansion',
'pad_block',
+ 'pkcs7_padding',
'unpad_pkcs7',
]