Add TODOs from code review

reference/reference.py

@@ -107,6 +107,7 @@ def chilldkg_finalize(
 # TODO Make this a subroutine of chilldkg_finalize, which should output the backup.
 # The backup must be written to permanent storage before using the dkg_output,
 # so it should be coupled with dkg_finalize.
+# TODO Fix Any type
 def chilldkg_backup(state2: ChillDKGStateR2, cert: bytes) -> Any:
     eta = state2[1]
     return (eta, cert)
@@ -127,6 +128,8 @@ async def chilldkg(
     chan.send(eq_round1)
     cert = await chan.receive()
     dkg_output = chilldkg_finalize(state2, cert)
+    # TODO We should probably not just return None here but raise instead.
+    # Raising a specific exception is also better for testing.
     if dkg_output is None:
         return None
 

reference/secp256k1ref/ecdh.py

@@ -4,6 +4,7 @@
 
 
 def ecdh_raw(seckey: bytes, pubkey: bytes):
+    """TODO"""
     x = Scalar.from_bytes(seckey)
     assert x != 0
     Y = GE.from_bytes_compressed(pubkey)
@@ -13,5 +14,6 @@ def ecdh_raw(seckey: bytes, pubkey: bytes):
 
 
 def ecdh_libsecp256k1(seckey: bytes, pubkey: bytes):
+    """TODO"""
     Z = ecdh_raw(seckey, pubkey)
     return hashlib.sha256(Z.to_bytes_compressed().digest())

reference/secp256k1ref/secp256k1.py

@@ -170,6 +170,7 @@ def sqrt(self):
 
 
 class Scalar(APrimeFE):
+    """TODO Docstring"""
     SIZE = 0xFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFEBAAEDCE6AF48A03BBFD25E8CD0364141
 
 

reference/simplpedpop.py

@@ -144,17 +144,16 @@ def signer_pre_finalize(
     for i in range(n):
         if i == idx:
             # No need to check our own pop.
-            # TODO Should we include a simple bytes comparison as defense-in-depth?
             continue
         if coms_to_secrets[i].infinity:
-            # TODO This branch can go away once we add real serializations.
-            # If the serialized pubkey is infinity, pop_verify will simply fail.
             raise InvalidContributionError(i, "Participant sent invalid commitment")
-        else:
-            if not pop_verify(pops[i], coms_to_secrets[i].to_bytes_xonly(), i):
-                raise InvalidContributionError(
-                    i, "Participant sent invalid proof-of-knowledge"
-                )
+        # This can be optimized: We serialize the coms_to_secrets[i] here, but
+        # pop_verify/schnorr_veriy will need to deserialize it again, which
+        # involves computing a square root to obtain the y coordinate.
+        if not pop_verify(pops[i], coms_to_secrets[i].to_bytes_xonly(), i):
+            raise InvalidContributionError(
+                i, "Participant sent invalid proof-of-knowledge"
+            )
     vss_commitment = assemble_sum_vss_commitment(
         coms_to_secrets, coms_to_nonconst_terms, t, n
     )

reference/util.py

@@ -13,6 +13,8 @@ def kdf(seed: bytes, tag: str, extra_input: bytes = b"") -> bytes:
     return tagged_hash_bip_dkg(tag + "KDF ", seed + extra_input)
 
 
+# TODO Document in all functions what exceptions they can raise
+
 class InvalidContributionError(Exception):
     def __init__(self, signer, error):
         self.signer = signer