Fix dataclass serialization to CBOR

fido2/client.py

@@ -47,10 +47,10 @@
 )
 from .cose import ES256
 from .rpid import verify_rp_id
-from .utils import sha256, _DataClassMapping
+from .utils import sha256
 from enum import IntEnum, unique
 from urllib.parse import urlparse
-from dataclasses import replace, asdict
+from dataclasses import replace
 from threading import Timer, Event
 from typing import (
     Type,
@@ -69,17 +69,6 @@
 logger = logging.getLogger(__name__)
 
 
-def _as_cbor(data):
-    if data is None:
-        return None
-    if isinstance(data, Sequence):
-        return [_as_cbor(d) for d in data]
-    if isinstance(data, _DataClassMapping):
-        # Remove empty values and do not serialize value
-        return {k: v for k, v in asdict(data).items() if v is not None}  # type: ignore
-    return data
-
-
 class ClientError(Exception):
     @unique
     class ERR(IntEnum):
@@ -814,10 +803,10 @@ def make_credential(
         try:
             return self._backend.do_make_credential(
                 client_data,
-                _as_cbor(rp),
-                _as_cbor(options.user),
-                _as_cbor(options.pub_key_cred_params),
-                _as_cbor(options.exclude_credentials),
+                rp,
+                options.user,
+                options.pub_key_cred_params,
+                options.exclude_credentials,
                 options.extensions,
                 selection.require_resident_key,
                 selection.user_verification,
@@ -859,7 +848,7 @@ def get_assertion(
             return self._backend.do_get_assertion(
                 client_data,
                 options.rp_id,
-                _as_cbor(options.allow_credentials),
+                options.allow_credentials,
                 options.extensions,
                 options.user_verification,
                 event,

fido2/ctap2/base.py

@@ -35,23 +35,37 @@
 from ..webauthn import AuthenticatorData, Aaguid
 
 from enum import IntEnum, unique
-from dataclasses import dataclass, field, fields, Field
+from dataclasses import dataclass, field, fields, Field, asdict
 from threading import Event
-from typing import Mapping, Dict, Any, List, Optional, Callable
+from typing import Mapping, Dict, Any, List, Optional, Callable, Sequence
 import struct
 import logging
 
 logger = logging.getLogger(__name__)
 
 
+def _as_cbor(data):
+    if data is None:
+        return None
+    # Avoid handling bytes | str as Sequence
+    if isinstance(data, (bytes, str)):
+        return data
+    if isinstance(data, Sequence):
+        return [_as_cbor(d) for d in data]
+    if isinstance(data, _DataClassMapping):
+        # Remove empty values and do not serialize value
+        return {k: v for k, v in asdict(data).items() if v is not None}  # type: ignore
+    return data
+
+
 def args(*params) -> Dict[int, Any]:
     """Constructs a dict from a list of arguments for sending a CBOR command.
     None elements will be omitted.
 
     :param params: Arguments, in order, to add to the command.
     :return: The input parameters as a dict.
     """
-    return dict((i, v) for i, v in enumerate(params, 1) if v is not None)
+    return dict((i, _as_cbor(v)) for i, v in enumerate(params, 1) if v is not None)
 
 
 class _CborDataObject(_DataClassMapping[int]):

tests/test_client.py

@@ -40,6 +40,9 @@
     PublicKeyCredentialCreationOptions,
     AttestationObject,
     CollectedClientData,
+    PublicKeyCredentialUserEntity,
+    PublicKeyCredentialRpEntity,
+    PublicKeyCredentialParameters,
 )
 
 
@@ -146,9 +149,9 @@ def test_make_credential_ctap2(self, PatchedCtap2):
 
         ctap2.make_credential.assert_called_with(
             response.client_data.hash,
-            rp,
-            user,
-            [{"type": "public-key", "alg": -7}],
+            PublicKeyCredentialRpEntity(**rp),
+            PublicKeyCredentialUserEntity(**user),
+            [PublicKeyCredentialParameters(**{"type": "public-key", "alg": -7})],
             None,
             None,
             None,