Fix eip4844 state transition functions

specs/eip4844/beacon-chain.md

@@ -125,7 +125,10 @@ def tx_peek_blob_versioned_hashes(opaque_tx: Transaction) -> Sequence[VersionedH
     message_offset = 1 + uint32.decode_bytes(opaque_tx[1:5])
     # field offset: 32 + 8 + 32 + 32 + 8 + 4 + 32 + 4 + 4 = 156
     blob_versioned_hashes_offset = uint32.decode_bytes(opaque_tx[(message_offset + 156):(message_offset + 160)])
-    return [VersionedHash(opaque_tx[x:(x + 32)]) for x in range(blob_versioned_hashes_offset, len(opaque_tx), 32)]
+    return [
+        VersionedHash(opaque_tx[x:(x + 32)])
+        for x in range(message_offset + blob_versioned_hashes_offset, len(opaque_tx), 32)
+    ]
 ```
 
 #### `verify_kzgs_against_transactions`

specs/eip4844/polynomial-commitments.md

@@ -93,7 +93,7 @@ def lincomb(points: Sequence[KZGCommitment], scalars: Sequence[BLSFieldElement])
     r = bls.Z1
     for x, a in zip(points, scalars):
         r = bls.add(r, bls.multiply(x, a))
-    return r
+    return KZGCommitment(kzg.G1_to_bytes48(r))
 ```
 
 #### `matrix_lincomb`

specs/eip4844/validator.md

@@ -185,7 +185,7 @@ blobs_sidecar = BlobsSidecar(
 And then signed:
 
 ```
-domain = get_domain(state, DOMAIN_BLOBS_SIDECAR, blobs_sidecar.beacon_block_slot / SLOTS_PER_EPOCH)
+domain = get_domain(state, DOMAIN_BLOBS_SIDECAR, blobs_sidecar.beacon_block_slot // SLOTS_PER_EPOCH)
 signing_root = compute_signing_root(blobs_sidecar, domain)
 signature = bls.Sign(privkey, signing_root)
 signed_blobs_sidecar = SignedBlobsSidecar(message=blobs_sidecar, signature=signature)

tests/core/pyspec/eth2spec/test/eip4844/sanity/test_blocks.py

@@ -0,0 +1,28 @@
+from eth2spec.test.helpers.state import (
+    state_transition_and_sign_block
+)
+from eth2spec.test.helpers.block import (
+    build_empty_block_for_next_slot
+)
+from eth2spec.test.context import (
+    spec_state_test,
+    with_eip4844_and_later,
+)
+from eth2spec.test.helpers.sharding import (
+    get_sample_opaque_tx,
+)
+
+
+@with_eip4844_and_later
+@spec_state_test
+def test_simple_blobs(spec, state):
+    yield 'pre', state
+
+    block = build_empty_block_for_next_slot(spec, state)
+    opaque_tx, _, blob_kzgs = get_sample_opaque_tx(spec)
+    block.body.blob_kzgs = blob_kzgs
+    block.body.execution_payload.transactions = [opaque_tx]
+    signed_block = state_transition_and_sign_block(spec, state, block)
+
+    yield 'blocks', [signed_block]
+    yield 'post', state

tests/core/pyspec/eth2spec/test/eip4844/unittests/test_kzg.py

@@ -1,27 +1,21 @@
 
-import random
 from eth2spec.test.helpers.constants import (
     EIP4844,
     MINIMAL,
 )
+from eth2spec.test.helpers.sharding import (
+    create_blob,
+)
 from eth2spec.test.context import (
     with_phases,
     spec_state_test,
     with_presets,
 )
 
 
-def _create_blob(spec):
-    rng = random.Random(5566)
-    return spec.Blob([
-        rng.randint(0, spec.BLS_MODULUS - 1)
-        for _ in range(spec.FIELD_ELEMENTS_PER_BLOB)
-    ])
-
-
 @with_phases([EIP4844])
 @spec_state_test
 @with_presets([MINIMAL])
 def test_blob_to_kzg(spec, state):
-    blob = _create_blob(spec)
+    blob = create_blob(spec)
     spec.blob_to_kzg(blob)

tests/core/pyspec/eth2spec/test/helpers/sharding.py

@@ -0,0 +1,81 @@
+import random
+from eth2spec.utils.ssz.ssz_typing import (
+    Container,
+    Bytes20, Bytes32,
+    ByteList,
+    List,
+    Union,
+    boolean,
+    uint256, uint64,
+)
+from eth2spec.utils.ssz.ssz_impl import serialize
+
+
+#
+# Containers from EIP-4844
+#
+MAX_CALLDATA_SIZE = 2**24
+MAX_VERSIONED_HASHES_LIST_SIZE = 2**24
+MAX_ACCESS_LIST_STORAGE_KEYS = 2**24
+MAX_ACCESS_LIST_SIZE = 2**24
+
+
+class AccessTuple(Container):
+    address: Bytes20  # Address = Bytes20
+    storage_keys: List[Bytes32, MAX_ACCESS_LIST_STORAGE_KEYS]
+
+
+class ECDSASignature(Container):
+    y_parity: boolean
+    r: uint256
+    s: uint256
+
+
+class BlobTransaction(Container):
+    chain_id: uint256
+    nonce: uint64
+    priority_fee_per_gas: uint256
+    max_basefee_per_gas: uint256
+    gas: uint64
+    to: Union[None, Bytes20]  # Address = Bytes20
+    value: uint256
+    data: ByteList[MAX_CALLDATA_SIZE]
+    access_list: List[AccessTuple, MAX_ACCESS_LIST_SIZE]
+    blob_versioned_hashes: List[Bytes32, MAX_VERSIONED_HASHES_LIST_SIZE]
+
+
+class SignedBlobTransaction(Container):
+    message: BlobTransaction
+    signature: ECDSASignature
+
+
+def create_blob(spec, rng=None):
+    if rng is None:
+        rng = random.Random(5566)
+
+    return spec.Blob([
+        rng.randint(0, spec.BLS_MODULUS - 1)
+        for _ in range(spec.FIELD_ELEMENTS_PER_BLOB)
+    ])
+
+
+def get_sample_opaque_tx(spec, blob_count=1, rng=None):
+    blobs = []
+    blob_kzgs = []
+    blob_versioned_hashes = []
+    for _ in range(blob_count):
+        blob = create_blob(spec, rng)
+        blob_kzg = spec.KZGCommitment(spec.blob_to_kzg(blob))
+        blob_versioned_hash = spec.kzg_to_versioned_hash(blob_kzg)
+        blobs.append(blob)
+        blob_kzgs.append(blob_kzg)
+        blob_versioned_hashes.append(blob_versioned_hash)
+
+    signed_blob_tx = SignedBlobTransaction(
+        message=BlobTransaction(
+            blob_versioned_hashes=blob_versioned_hashes,
+        )
+    )
+    serialized_tx = serialize(signed_blob_tx)
+    opaque_tx = spec.uint_to_bytes(spec.BLOB_TX_TYPE) + serialized_tx
+    return opaque_tx, blobs, blob_kzgs

tests/core/pyspec/eth2spec/utils/kzg.py

@@ -1,5 +1,4 @@
 # Ref: https://github.com/ethereum/research/blob/8f084630528ba33d92b2bc05edf5338dd193c6f1/trusted_setup/trusted_setup.py
-
 from py_ecc.optimized_bls12_381 import (  # noqa: F401
     G1,
     G2,
@@ -11,6 +10,9 @@
     multiply,
     neg,
 )
+from py_ecc.bls.g2_primitives import (  # noqa: F401
+    G1_to_pubkey as G1_to_bytes48,
+)
 
 
 PRIMITIVE_ROOT_OF_UNITY = 7