Coverage for /pythoncovmergedfiles/medio/medio/src/acme2certifier/fuzz/jwk_signature_fuzzer.py: 47%

1###### Coverage stub 

2import atexit 

3import coverage 

4cov = coverage.coverage(data_file='.coverage', cover_pylib=True) 

5cov.start() 

6# Register an exist handler that will print coverage 

7def exit_handler(): 

8 cov.stop() 

9 cov.save() 

10atexit.register(exit_handler) 

11####### End of coverage stub 

12#!/usr/bin/python3 

13# Copyright 2026 grindsa 

14# 

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

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

17# You may obtain a copy of the License at 

18# 

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

20# 

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

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

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

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

25# limitations under the License. 

26"""Fuzz JWK thumbprint and JWS signature verification helpers.""" 

27 

28import json 

29import logging 

30import sys 

31 

32import atheris 

33 

34with atheris.instrument_imports(): 

35 from acme2certifier.acme_srv.helpers.crypto import ( 

36 jwk_thumbprint_get, 

37 signature_check, 

38 ) 

39 

40_LOGGER = logging.getLogger("fuzz") 

41_LOGGER.addHandler(logging.NullHandler()) 

42_LOGGER.setLevel(logging.CRITICAL) 

43 

44 

45def TestOneInput(data: bytes) -> None: 

46 """Fuzz jwk_thumbprint_get and signature_check.""" 

47 fdp = atheris.FuzzedDataProvider(data) 

48 as_json = fdp.ConsumeBool() 

49 key_blob = fdp.ConsumeUnicodeNoSurrogates(max(1, fdp.remaining_bytes() // 2)) 

50 message = fdp.ConsumeUnicodeNoSurrogates(fdp.remaining_bytes()) 

51 

52 # Thumbprint expects a dict; tolerate invalid JSON. 

53 try: 

54 pub_dict = json.loads(key_blob) 

55 if isinstance(pub_dict, dict): 

56 jwk_thumbprint_get(_LOGGER, pub_dict) 

57 except Exception: 

58 pass 

59 

60 # signature_check: json_=True wants a JSON string; False wants a mapping. 

61 try: 

62 if as_json: 

63 signature_check(_LOGGER, message, key_blob, json_=True) 

64 else: 

65 try: 

66 pub_key = json.loads(key_blob) 

67 except Exception: 

68 pub_key = key_blob 

69 signature_check(_LOGGER, message, pub_key, json_=False) 

70 except Exception: 

71 pass 

72 

73 

74def main() -> None: 

75 """Entrypoint for Atheris / OSS-Fuzz.""" 

76 atheris.Setup(sys.argv, TestOneInput) 

77 atheris.Fuzz() 

78 

79 

80if __name__ == "__main__": 

81 main()