build tree

pysetup/spec_builders/deneb.py

@@ -28,11 +28,9 @@ def retrieve_blobs_and_proofs(beacon_block_root: Root) -> Tuple[Sequence[Blob],
 
 def compute_commitment_inclusion_proof(
     body: BeaconBlockBody,
-    blob_kzg_commitments: Sequence[KZGCommitment],
-    index: int
-) -> List[Bytes32, KZG_COMMITMENT_INCLUSION_PROOF_DEPTH]:
-    # pylint: disable=unused-argument
-    return []
+    index: GeneralizedIndex
+) -> Sequence[Bytes32]:
+    return build_proof(body.get_backing(), index)
 '''
 
     @classmethod

specs/deneb/beacon-chain.md

@@ -187,6 +187,19 @@ def kzg_commitment_to_versioned_hash(kzg_commitment: KZGCommitment) -> Versioned
     return VERSIONED_HASH_VERSION_KZG + hash(kzg_commitment)[1:]
 ```
 
+#### `is_valid_merkle_path`
+
+```python
+def is_valid_merkle_path(leaf: Bytes32, branch: Sequence[Bytes32], gindex: int, root: Root) -> bool:
+    value = leaf
+    for i in range(len(branch)):
+        if (gindex >> i) & 1 == 0:
+            value = hash(branch[i] + value)
+        else:
+            value = hash(value + branch[i])
+    return value == root
+```
+
 ### Beacon state accessors
 
 #### Modified `get_attestation_participation_flag_indices`

specs/deneb/p2p-interface.md

@@ -51,7 +51,7 @@ The specification of these changes continues in the same format as the network s
 | `MAX_REQUEST_BLOB_SIDECARS`              | `MAX_REQUEST_BLOCKS_DENEB * MAX_BLOBS_PER_BLOCK` | Maximum number of blob sidecars in a single request  |
 | `MIN_EPOCHS_FOR_BLOB_SIDECARS_REQUESTS`  | `2**12` (= 4096 epochs, ~18 days) | The minimum epoch range over which a node must serve blob sidecars  |
 | `BLOB_SIDECAR_SUBNET_COUNT`              | `6`                               | The number of blob sidecar subnets used in the gossipsub protocol.  |
-| `BLOB_KZG_COMMITMENTS_GINDEX`            | `4 ** 2 + 11` (= 27)              | `blob_kzg_commitments` field gindex on `BeaconBlockBody` container  |
+| `BLOB_KZG_COMMITMENTS_GINDEX`            | `get_generalized_index(BeaconBlockBody, 'blob_kzg_commitments')`  (= 27) | `blob_kzg_commitments` field gindex on `BeaconBlockBody` container  |
 | `KZG_COMMITMENT_INCLUSION_PROOF_DEPTH`   | `floorlog2(BLOB_KZG_COMMITMENTS_GINDEX) + 1 + ceillog2(MAX_BLOB_COMMITMENTS_PER_BLOCK)  # noqa: E501` | Merkle proof for `blob_kzg_commitments` list item |
 
 ### Containers
@@ -86,29 +86,14 @@ class BlobIdentifier(Container):
 
 ```python
 def verify_blob_sidecar_inclusion_proof(blob_sidecar: BlobSidecar) -> bool:
-    commitment_item_gindex = MAX_BLOB_COMMITMENTS_PER_BLOCK + blob_sidecar.index
-    gindex = BLOB_KZG_COMMITMENTS_GINDEX + commitment_item_gindex << floorlog2(BLOB_KZG_COMMITMENTS_GINDEX)
     return is_valid_merkle_path(
         leaf=blob_sidecar.kzg_commitment.hash_tree_root(),
         branch=blob_sidecar.commitment_inclusion_proof,
-        gindex=gindex,
+        gindex=get_generalized_index(BeaconBlockBody, 'blob_kzg_commitments', blob_sidecar.index),
         root=blob_sidecar.signed_block_header.message.body_root,
     )
 ```
 
-#### `is_valid_merkle_path`
-
-```python
-def is_valid_merkle_path(leaf: Bytes32, branch: Sequence[Bytes32], gindex: int, root: Root) -> bool:
-    value = leaf
-    for i in range(len(branch)):
-        if (gindex >> i) & 1 == 0:
-            value = hash(branch[i] + value)
-        else:
-            value = hash(value + branch[i])
-    return value == root
-```
-
 ### The gossip domain: gossipsub
 
 Some gossip meshes are upgraded in the fork of Deneb to support upgraded types.

specs/deneb/validator.md

@@ -165,8 +165,7 @@ def get_blob_sidecars(signed_block: SignedBeaconBlock,
             kzg_proof=blob_kzg_proofs[index],
             commitment_inclusion_proof=compute_commitment_inclusion_proof(
                 block.body,
-                block.body.blob_kzg_commitments[index],
-                index,
+                get_generalized_index(BeaconBlockBody, 'blob_kzg_commitments', index),
             ),
             signed_block_header=signed_block_header,
         )

tests/core/pyspec/eth2spec/test/deneb/unittests/validator/test_validator.py

@@ -34,7 +34,6 @@ def get_blob_sidecars(spec, signed_block, blobs, blob_kzg_proofs):
             commitment_inclusion_proof=compute_commitment_inclusion_proof(
                 spec,
                 signed_block.message.body,
-                signed_block.message.body.blob_kzg_commitments[index],
                 index,
             ),
             signed_block_header=signed_block_header,
@@ -43,10 +42,9 @@ def get_blob_sidecars(spec, signed_block, blobs, blob_kzg_proofs):
     ]
 
 
-def compute_commitment_inclusion_proof(spec, body, kzg_commitment, index):
-    gindex = (spec.BeaconBlockBody / 'blob_kzg_commitments' / index).gindex()
-    raise Exception('todo, does remerkleable expose an API to compute proofs?')
-    return gindex
+def compute_commitment_inclusion_proof(spec, body, index):
+    gindex = spec.get_generalized_index(spec.BeaconBlockBody, 'blob_kzg_commitments', index)
+    return spec.build_proof(body, gindex)
 
 
 @with_deneb_and_later