Coverage for aiocoap/cli/keygen.py: 22%

1# SPDX-FileCopyrightText: Christian Amsüss and the aiocoap contributors 

2# 

3# SPDX-License-Identifier: MIT 

4 

5"""A tool for creating key pairs for use in credentials 

6 

7Note that this tool operates on secrets stored in unencrypted files, protectd 

8by restrictively set file system permissions. While this is common practice 

9with many tools in the UNIX world, it might be surprising to users coming from 

10multi-factor environments.""" 

11 

12import aiocoap.meta 

13import aiocoap.defaults 

14 

15import argparse 

16from pathlib import Path 

17 

18 

19def build_parser(): 

20 p = argparse.ArgumentParser(description=__doc__) 

21 p.add_argument( 

22 "--version", action="version", version="%(prog)s " + aiocoap.meta.version 

23 ) 

24 

25 subparsers = p.add_subparsers(required=True, dest="subcommand") 

26 generate = subparsers.add_parser( 

27 "generate", 

28 help="This generates an" 

29 " EDHOC key, stores it in a key file that is only readable by the" 

30 " user, and prints the corresponding public key information in a way" 

31 " suitable for inclusion in credentials maps.", 

32 ) 

33 generate.add_argument("keyfile", help="File to store the secret key in", type=Path) 

34 generate.add_argument( 

35 "--kid", help="Hexadecimal key identifier", type=bytes.fromhex 

36 ) 

37 generate.add_argument("--subject", help="Text placed in the CCS", type=str) 

38 

39 return p 

40 

41 

42def main(): 

43 p = build_parser() 

44 

45 args = p.parse_args() 

46 

47 missmods = aiocoap.defaults.oscore_missing_modules() 

48 if missmods: 

49 p.error( 

50 f"Dependencies missing, consider installing aiocoap as \"aiocoap[oscore]\" or \"aiocoap[all]\". Missing modules: {', '.join(missmods)}" 

51 ) 

52 

53 from aiocoap import edhoc 

54 import cbor2 

55 import cbor_diag 

56 

57 if args.subcommand == "generate": 

58 try: 

59 key = edhoc.CoseKeyForEdhoc.generate(args.keyfile) 

60 except FileExistsError: 

61 raise p.error("Output file already exists") 

62 

63 public = key.as_ccs(args.kid, args.subject) 

64 print(cbor_diag.cbor2diag(cbor2.dumps(public, canonical=True), pretty=False)) 

65 else: 

66 raise RuntimeError(f"Unimplemented subcommand {args.subcommand=}") 

67 

68 

69if __name__ == "__main__": 

70 main()