3.2 KiB
3.2 KiB
Deneb Light Client -- Sync Protocol
Notice: This document is a work-in-progress for researchers and implementers.
Table of contents
Introduction
This upgrade updates light client data to include the Deneb changes to the ExecutionPayload structure. It extends the Capella Light Client specifications. The fork document explains how to upgrade existing Capella based deployments to Deneb.
Additional documents describes the impact of the upgrade on certain roles:
Helper functions
Modified get_lc_execution_root
def get_lc_execution_root(header: LightClientHeader) -> Root:
epoch = compute_epoch_at_slot(header.beacon.slot)
# [New in Deneb]
if epoch >= DENEB_FORK_EPOCH:
return hash_tree_root(header.execution)
# [Modified in Deneb]
if epoch >= CAPELLA_FORK_EPOCH:
execution_header = capella.ExecutionPayloadHeader(
parent_hash=header.execution.parent_hash,
fee_recipient=header.execution.fee_recipient,
state_root=header.execution.state_root,
receipts_root=header.execution.receipts_root,
logs_bloom=header.execution.logs_bloom,
prev_randao=header.execution.prev_randao,
block_number=header.execution.block_number,
gas_limit=header.execution.gas_limit,
gas_used=header.execution.gas_used,
timestamp=header.execution.timestamp,
extra_data=header.execution.extra_data,
base_fee_per_gas=header.execution.base_fee_per_gas,
block_hash=header.execution.block_hash,
transactions_root=header.execution.transactions_root,
withdrawals_root=header.execution.withdrawals_root,
)
return hash_tree_root(execution_header)
return Root()
Modified is_valid_light_client_header
def is_valid_light_client_header(header: LightClientHeader) -> bool:
epoch = compute_epoch_at_slot(header.beacon.slot)
# [New in Deneb:EIP4844]
if epoch < DENEB_FORK_EPOCH:
if header.execution.data_gas_used != uint64(0) or header.execution.excess_data_gas != uint64(0):
return False
if epoch < CAPELLA_FORK_EPOCH:
return (
header.execution == ExecutionPayloadHeader()
and header.execution_branch == [Bytes32() for _ in range(floorlog2(EXECUTION_PAYLOAD_INDEX))]
)
return is_valid_merkle_branch(
leaf=get_lc_execution_root(header),
branch=header.execution_branch,
depth=floorlog2(EXECUTION_PAYLOAD_INDEX),
index=get_subtree_index(EXECUTION_PAYLOAD_INDEX),
root=header.beacon.body_root,
)