Encode credentials as a protocol buffer message

This permits to decode a credential of a different version without failing.

src/ctap/storage.rs

@@ -16,9 +16,9 @@ use crate::crypto::rng256::Rng256;
 use crate::ctap::data_formats::PublicKeyCredentialSource;
 use crate::ctap::status_code::Ctap2StatusCode;
 use crate::ctap::PIN_AUTH_LENGTH;
+use alloc::collections::BTreeMap;
 use alloc::string::String;
 use alloc::vec::Vec;
-use core::convert::TryInto;
 use ctap2::embedded_flash::{self, StoreConfig, StoreEntry, StoreError, StoreIndex};
 
 #[cfg(any(test, feature = "ram_storage"))]
@@ -420,8 +420,7 @@ impl From<StoreError> for Ctap2StatusCode {
 }
 
 fn deserialize_credential(data: &[u8]) -> Option<PublicKeyCredentialSource> {
-    let cbor = cbor::read(data).ok()?;
-    cbor.try_into().ok()
+    PublicKeyCredentialSource::parse_cbor(cbor::read(data).ok()?)
 }
 
 fn serialize_credential(credential: PublicKeyCredentialSource) -> Result<Vec<u8>, Ctap2StatusCode> {
@@ -454,6 +453,7 @@ mod test {
             user_handle,
             other_ui: None,
             cred_random: None,
+            unknown_fields: BTreeMap::new(),
         }
     }
 
@@ -623,6 +623,7 @@ mod test {
             user_handle: vec![0x00],
             other_ui: None,
             cred_random: None,
+            unknown_fields: BTreeMap::new(),
         };
         assert_eq!(found_credential, Some(expected_credential));
     }