fix: review feedback

Signed-off-by: Chris Gianelloni <wolf31o2@blinklabs.io>

Author: wolf31o2

ledger/common/certs.go

@@ -413,26 +413,46 @@ type LeiosKey struct {
 	PossessionProof []byte `json:"possessionProof"`
 }
 
-func (k *LeiosKey) UnmarshalCBOR(data []byte) error {
-	type tmpLeiosKey LeiosKey
-	var tmp tmpLeiosKey
-	if _, err := cbor.Decode(data, &tmp); err != nil {
-		return err
-	}
-	if len(tmp.PublicKey) != LeiosBlsPublicKeySize {
+func (k LeiosKey) validate() error {
+	if len(k.PublicKey) != LeiosBlsPublicKeySize {
 		return fmt.Errorf(
 			"invalid Leios BLS public key length: expected %d, got %d",
 			LeiosBlsPublicKeySize,
-			len(tmp.PublicKey),
+			len(k.PublicKey),
 		)
 	}
-	if len(tmp.PossessionProof) != LeiosBlsPossessionProofSize {
+	if len(k.PossessionProof) != LeiosBlsPossessionProofSize {
 		return fmt.Errorf(
 			"invalid Leios BLS possession proof length: expected %d, got %d",
 			LeiosBlsPossessionProofSize,
-			len(tmp.PossessionProof),
+			len(k.PossessionProof),
 		)
 	}
+	return nil
+}
+
+func (k *LeiosKey) UnmarshalCBOR(data []byte) error {
+	type tmpLeiosKey LeiosKey
+	var tmp tmpLeiosKey
+	if _, err := cbor.Decode(data, &tmp); err != nil {
+		return err
+	}
+	if err := LeiosKey(tmp).validate(); err != nil {
+		return err
+	}
+	*k = LeiosKey(tmp)
+	return nil
+}
+
+func (k *LeiosKey) UnmarshalJSON(data []byte) error {
+	type tmpLeiosKey LeiosKey
+	var tmp tmpLeiosKey
+	if err := json.Unmarshal(data, &tmp); err != nil {
+		return err
+	}
+	if err := LeiosKey(tmp).validate(); err != nil {
+		return err
+	}
 	*k = LeiosKey(tmp)
 	return nil
 }
@@ -766,6 +786,9 @@ func (c *PoolRegistrationCertificate) UnmarshalCBOR(cborData []byte) error {
 	return nil
 }
 
+// NOTE: UnmarshalCBOR caches the original CBOR bytes, and MarshalCBOR returns
+// those bytes for both 10- and 11-field variants. Call SetCbor(nil) before
+// marshaling mutated fields.
 func (c PoolRegistrationCertificate) MarshalCBOR() ([]byte, error) {
 	if cborData := c.Cbor(); cborData != nil {
 		return cborData, nil

ledger/common/certs_test.go

@@ -299,6 +299,17 @@ func TestLeiosKeyRejectsInvalidLengths(t *testing.T) {
 			var decoded LeiosKey
 			_, err = cbor.Decode(encoded, &decoded)
 			require.Error(t, err)
+
+			encoded, err = json.Marshal(struct {
+				PublicKey       []byte `json:"publicKey"`
+				PossessionProof []byte `json:"possessionProof"`
+			}{
+				PublicKey:       test.key,
+				PossessionProof: test.proof,
+			})
+			require.NoError(t, err)
+			err = json.Unmarshal(encoded, &decoded)
+			require.Error(t, err)
 		})
 	}
 }