Coverage for /pythoncovmergedfiles/medio/medio/usr/local/lib/python3.8/site-packages/nacl/bindings/crypto_shorthash.py: 50%

1# Copyright 2016 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 nacl.exceptions as exc 

17from nacl._sodium import ffi, lib 

18from nacl.exceptions import ensure 

19 

20 

21has_crypto_shorthash_siphashx24 = bool( 

22 lib.PYNACL_HAS_CRYPTO_SHORTHASH_SIPHASHX24 

23) 

24 

25BYTES: int = lib.crypto_shorthash_siphash24_bytes() 

26KEYBYTES: int = lib.crypto_shorthash_siphash24_keybytes() 

27 

28XBYTES = 0 

29XKEYBYTES = 0 

30 

31if has_crypto_shorthash_siphashx24: 

32 XBYTES = lib.crypto_shorthash_siphashx24_bytes() 

33 XKEYBYTES = lib.crypto_shorthash_siphashx24_keybytes() 

34 

35 

36def crypto_shorthash_siphash24(data: bytes, key: bytes) -> bytes: 

37 """Compute a fast, cryptographic quality, keyed hash of the input data 

38 

39 :param data: 

40 :type data: bytes 

41 :param key: len(key) must be equal to 

42 :py:data:`.KEYBYTES` (16) 

43 :type key: bytes 

44 """ 

45 if len(key) != KEYBYTES: 

46 raise exc.ValueError( 

47 "Key length must be exactly {} bytes".format(KEYBYTES) 

48 ) 

49 digest = ffi.new("unsigned char[]", BYTES) 

50 rc = lib.crypto_shorthash_siphash24(digest, data, len(data), key) 

51 

52 ensure(rc == 0, raising=exc.RuntimeError) 

53 return ffi.buffer(digest, BYTES)[:] 

54 

55 

56def crypto_shorthash_siphashx24(data: bytes, key: bytes) -> bytes: 

57 """Compute a fast, cryptographic quality, keyed hash of the input data 

58 

59 :param data: 

60 :type data: bytes 

61 :param key: len(key) must be equal to 

62 :py:data:`.XKEYBYTES` (16) 

63 :type key: bytes 

64 :raises nacl.exceptions.UnavailableError: If called when using a 

65 minimal build of libsodium. 

66 """ 

67 ensure( 

68 has_crypto_shorthash_siphashx24, 

69 "Not available in minimal build", 

70 raising=exc.UnavailableError, 

71 ) 

72 

73 if len(key) != XKEYBYTES: 

74 raise exc.ValueError( 

75 "Key length must be exactly {} bytes".format(XKEYBYTES) 

76 ) 

77 digest = ffi.new("unsigned char[]", XBYTES) 

78 rc = lib.crypto_shorthash_siphashx24(digest, data, len(data), key) 

79 

80 ensure(rc == 0, raising=exc.RuntimeError) 

81 return ffi.buffer(digest, XBYTES)[:]