Coverage for ledger/hsm2dongle_cmds/powhsm_attestation.py: 100%

1# The MIT License (MIT) 

2# 

3# Copyright (c) 2021 RSK Labs Ltd 

4# 

5# Permission is hereby granted, free of charge, to any person obtaining a copy of 

6# this software and associated documentation files (the "Software"), to deal in 

7# the Software without restriction, including without limitation the rights to 

8# use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies 

9# of the Software, and to permit persons to whom the Software is furnished to do 

10# so, subject to the following conditions: 

11# 

12# The above copyright notice and this permission notice shall be included in all 

13# copies or substantial portions of the Software. 

14# 

15# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 

16# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 

17# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE 

18# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER 

19# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, 

20# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE 

21# SOFTWARE. 

22 

23from enum import IntEnum 

24from .command import HSM2DongleCommand 

25 

26 

27class Op(IntEnum): 

28 OP_GET = 0x01 

29 OP_GET_MESSAGE = 0x02 

30 OP_APP_HASH = 0x03 

31 OP_GET_ENVELOPE = 0x04 

32 

33 

34LEGACY_HEADER = b"HSM:SIGNER:" 

35 

36 

37# Implements the powhsm attestation protocol against a 

38# running powhsm 

39class PowHsmAttestation(HSM2DongleCommand): 

40 Command = 0x50 

41 

42 def run(self, ud_value_hex): 

43 # Retrieve attestation signature 

44 signature = self.send(Op.OP_GET, 

45 bytes.fromhex(ud_value_hex))[self.Offset.DATA:] 

46 

47 # Retrieve message and envelope 

48 bufs = {} 

49 brk = False 

50 msgoffset = 1 # For legacy behavior handling 

51 for (op, name) in \ 

52 [(Op.OP_GET_MESSAGE, "message"), (Op.OP_GET_ENVELOPE, "envelope")]: 

53 # Legacy behavior handling 

54 if brk: 

55 bufs["envelope"] = bufs["message"] 

56 break 

57 bufs[name] = b'' 

58 more = True 

59 page = 0 

60 while more: 

61 result = self.send(op, bytes([page])) 

62 more = result[self.Offset.DATA] == 1 

63 # Legacy behavior handling 

64 if name == "message" and \ 

65 result[self.Offset.DATA:self.Offset.DATA+len(LEGACY_HEADER)] == \ 

66 LEGACY_HEADER: 

67 msgoffset = 0 

68 more = False 

69 brk = True 

70 bufs[name] += result[self.Offset.DATA+msgoffset:] 

71 page += 1 

72 

73 # Get signer hash 

74 signer_hash = self.send(Op.OP_APP_HASH)[self.Offset.DATA:] 

75 

76 return { 

77 "app_hash": signer_hash.hex(), 

78 "envelope": bufs["envelope"].hex(), 

79 "message": bufs["message"].hex(), 

80 "signature": signature.hex(), 

81 }