fido2: Apply flake8 lints

Makefile

@@ -6,7 +6,14 @@ PYTHON3=python3
 PYTHON3_VENV=venv/bin/python3
 
 # whitelist of directories for flake8
-FLAKE8_DIRS=pynitrokey/cli/fido2.py pynitrokey/cli/nk3 pynitrokey/cli/nkfido2.py pynitrokey/cli/nkpk.py pynitrokey/cli/trussed
+FLAKE8_DIRS=\
+	pynitrokey/cli/fido2.py \
+	pynitrokey/cli/nk3 \
+	pynitrokey/cli/nkfido2.py \
+	pynitrokey/cli/nkpk.py \
+	pynitrokey/cli/trussed \
+	pynitrokey/fido2/__init__.py \
+	pynitrokey/fido2/client.py
 
 all: init
 

pynitrokey/fido2/__init__.py

@@ -1,10 +1,10 @@
 import time
-from typing import Any, Callable, List, Optional, Union
+from typing import List, Optional, Union
 
 import usb
-from fido2.hid import CtapHidDevice, open_device
+from fido2.hid import CtapHidDevice
 
-from pynitrokey.exceptions import NonUniqueDeviceError, NoSoloFoundError
+from pynitrokey.exceptions import NoSoloFoundError
 
 # from pynitrokey.fido2 import hmac_secret
 from pynitrokey.fido2.client import NKFido2Client

pynitrokey/fido2/client.py

@@ -8,40 +8,23 @@
 # copied, modified, or distributed except according to those terms.
 
 import base64
-import binascii
-import hashlib
 import json
-import secrets
 import struct
 import sys
 import tempfile
 import time
-from typing import Any, Callable, List, Optional, Tuple, Union
+from typing import Optional, Tuple, Union
 
-from fido2.client import Fido2Client
-from fido2.cose import ES256, EdDSA
 from fido2.ctap import CtapError
 from fido2.ctap1 import Ctap1
 from fido2.ctap2.base import Ctap2
-from fido2.ctap2.pin import ClientPin
 from fido2.hid import CTAPHID, CtapHidDevice, open_device
-from fido2.webauthn import (
-    AuthenticatorSelectionCriteria,
-    PublicKeyCredentialCreationOptions,
-    PublicKeyCredentialParameters,
-    PublicKeyCredentialRpEntity,
-    PublicKeyCredentialType,
-    PublicKeyCredentialUserEntity,
-    ResidentKeyRequirement,
-    UserVerificationRequirement,
-)
 from intelhex import IntelHex
 
 import pynitrokey.exceptions
-import pynitrokey.fido2 as nkfido2
 from pynitrokey import helpers
 from pynitrokey.fido2.commands import SoloBootloader, SoloExtension
-from pynitrokey.helpers import local_critical, local_print
+from pynitrokey.helpers import local_critical
 
 
 class NKFido2Client:
@@ -104,7 +87,7 @@ def find_device(
 
         try:
             self.ctap2: Optional[Ctap2] = Ctap2(self.dev)
-        except CtapError as e:
+        except CtapError:
             self.ctap2 = None
 
         if self.exchange == self.exchange_hid:
@@ -253,7 +236,7 @@ def is_bootloader(self) -> bool:
                 pass
             else:
                 raise (e)
-        except Exception as e:
+        except Exception:
             # exception during bootloader version check, assume no bootloader
             # local_print("could not get bootloader version")
             pass
@@ -273,7 +256,7 @@ def enter_st_dfu(self) -> None:
         else:
             self.send_only_hid(SoloBootloader.HIDCommandEnterSTBoot, b"")
 
-    def program_file(self, name: str) -> bytes:
+    def program_file(self, name: str) -> bytes:  # noqa: C901
         def parseField(f: str) -> bytes:
             return base64.b64decode(helpers.from_websafe(f).encode())
 
@@ -308,7 +291,7 @@ def isCorrectVersion(current: Tuple[int, int, int], target: str) -> bool:
             if "versions" in firmware_file_data:
                 current = (0, 0, 0)
                 try:
-                    current = self.bootloader_version()
+                    current = self.bootloader_version()  # noqa: F841
                 except CtapError as e:
                     if e.code == CtapError.ERR.INVALID_COMMAND:
                         pass