Coverage for /pythoncovmergedfiles/medio/medio/usr/local/lib/python3.11/site-packages/cryptography/hazmat/primitives/padding.py: 63%

1# This file is dual licensed under the terms of the Apache License, Version 

2# 2.0, and the BSD License. See the LICENSE file in the root of this repository 

3# for complete details. 

4 

5from __future__ import annotations 

6 

7import abc 

8 

9from cryptography import utils 

10from cryptography.hazmat.bindings._rust import ( 

11 ANSIX923PaddingContext, 

12 ANSIX923UnpaddingContext, 

13 PKCS7PaddingContext, 

14 PKCS7UnpaddingContext, 

15) 

16 

17 

18class PaddingContext(metaclass=abc.ABCMeta): 

19 @abc.abstractmethod 

20 def update(self, data: utils.Buffer) -> bytes: 

21 """ 

22 Pads the provided bytes and returns any available data as bytes. 

23 """ 

24 

25 @abc.abstractmethod 

26 def finalize(self) -> bytes: 

27 """ 

28 Finalize the padding, returns bytes. 

29 """ 

30 

31 

32def _byte_padding_check(block_size: int) -> None: 

33 if not (0 <= block_size <= 2040): 

34 raise ValueError("block_size must be in range(0, 2041).") 

35 

36 if block_size % 8 != 0: 

37 raise ValueError("block_size must be a multiple of 8.") 

38 

39 

40class PKCS7: 

41 def __init__(self, block_size: int): 

42 _byte_padding_check(block_size) 

43 self.block_size = block_size 

44 

45 def padder(self) -> PaddingContext: 

46 return PKCS7PaddingContext(self.block_size) 

47 

48 def unpadder(self) -> PaddingContext: 

49 return PKCS7UnpaddingContext(self.block_size) 

50 

51 

52PaddingContext.register(PKCS7PaddingContext) 

53PaddingContext.register(PKCS7UnpaddingContext) 

54 

55 

56class ANSIX923: 

57 def __init__(self, block_size: int): 

58 _byte_padding_check(block_size) 

59 self.block_size = block_size 

60 

61 def padder(self) -> PaddingContext: 

62 return ANSIX923PaddingContext(self.block_size) 

63 

64 def unpadder(self) -> PaddingContext: 

65 return ANSIX923UnpaddingContext(self.block_size) 

66 

67 

68PaddingContext.register(ANSIX923PaddingContext) 

69PaddingContext.register(ANSIX923UnpaddingContext)