Coverage for /pythoncovmergedfiles/medio/medio/usr/local/lib/python3.8/site-packages/PyNaCl-1.6.0.dev1-py3.8-linux-x86_64.egg/nacl/utils.py: 67%

1# Copyright 2013 Donald Stufft and individual contributors 

2# 

3# Licensed under the Apache License, Version 2.0 (the "License"); 

4# you may not use this file except in compliance with the License. 

5# You may obtain a copy of the License at 

6# 

7# http://www.apache.org/licenses/LICENSE-2.0 

8# 

9# Unless required by applicable law or agreed to in writing, software 

10# distributed under the License is distributed on an "AS IS" BASIS, 

11# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 

12# See the License for the specific language governing permissions and 

13# limitations under the License. 

14 

15 

16import os 

17from typing import SupportsBytes, Type, TypeVar 

18 

19import nacl.bindings 

20from nacl import encoding 

21 

22_EncryptedMessage = TypeVar("_EncryptedMessage", bound="EncryptedMessage") 

23 

24 

25class EncryptedMessage(bytes): 

26 """ 

27 A bytes subclass that holds a messaged that has been encrypted by a 

28 :class:`SecretBox`. 

29 """ 

30 

31 _nonce: bytes 

32 _ciphertext: bytes 

33 

34 @classmethod 

35 def _from_parts( 

36 cls: Type[_EncryptedMessage], 

37 nonce: bytes, 

38 ciphertext: bytes, 

39 combined: bytes, 

40 ) -> _EncryptedMessage: 

41 obj = cls(combined) 

42 obj._nonce = nonce 

43 obj._ciphertext = ciphertext 

44 return obj 

45 

46 @property 

47 def nonce(self) -> bytes: 

48 """ 

49 The nonce used during the encryption of the :class:`EncryptedMessage`. 

50 """ 

51 return self._nonce 

52 

53 @property 

54 def ciphertext(self) -> bytes: 

55 """ 

56 The ciphertext contained within the :class:`EncryptedMessage`. 

57 """ 

58 return self._ciphertext 

59 

60 

61class StringFixer: 

62 def __str__(self: SupportsBytes) -> str: 

63 return str(self.__bytes__()) 

64 

65 

66def bytes_as_string(bytes_in: bytes) -> str: 

67 return bytes_in.decode("ascii") 

68 

69 

70def random(size: int = 32) -> bytes: 

71 return os.urandom(size) 

72 

73 

74def randombytes_deterministic( 

75 size: int, seed: bytes, encoder: encoding.Encoder = encoding.RawEncoder 

76) -> bytes: 

77 """ 

78 Returns ``size`` number of deterministically generated pseudorandom bytes 

79 from a seed 

80 

81 :param size: int 

82 :param seed: bytes 

83 :param encoder: The encoder class used to encode the produced bytes 

84 :rtype: bytes 

85 """ 

86 raw_data = nacl.bindings.randombytes_buf_deterministic(size, seed) 

87 

88 return encoder.encode(raw_data)