From f06a3b82e7f97f12f1f70e07f5a09b854755b8a1 Mon Sep 17 00:00:00 2001 From: Danny Ryan Date: Mon, 11 Mar 2019 14:38:10 -0600 Subject: [PATCH] cache current and previous justified root in state --- specs/core/0_beacon-chain.md | 17 +++++++++++------ 1 file changed, 11 insertions(+), 6 deletions(-) diff --git a/specs/core/0_beacon-chain.md b/specs/core/0_beacon-chain.md index ceca50962..0a86db3f9 100644 --- a/specs/core/0_beacon-chain.md +++ b/specs/core/0_beacon-chain.md @@ -613,6 +613,8 @@ The types are defined topologically to aid in facilitating an executable version 'current_epoch_attestations': [PendingAttestation], 'previous_justified_epoch': 'uint64', 'justified_epoch': 'uint64', + 'previous_justified_root': 'bytes32', + 'justified_root': 'bytes32', 'justification_bitfield': 'uint64', 'finalized_epoch': 'uint64', @@ -1546,6 +1548,8 @@ def get_genesis_beacon_state(genesis_validator_deposits: List[Deposit], current_epoch_attestations=[], previous_justified_epoch=GENESIS_EPOCH, justified_epoch=GENESIS_EPOCH, + previous_justified_root=ZERO_HASH, + justified_root=ZERO_HASH, justification_bitfield=0, finalized_epoch=GENESIS_EPOCH, @@ -1830,7 +1834,9 @@ def update_justification_and_finalization(state: BeaconState) -> None: # Rotate justified epochs state.previous_justified_epoch = state.justified_epoch + state.previous_justified_root = state.justified_root state.justified_epoch = new_justified_epoch + state.justified_root = get_block_root(state, get_epoch_start_slot(new_justified_epoch)) ``` #### Crosslinks @@ -2374,16 +2380,15 @@ def process_attestation(state: BeaconState, attestation: Attestation) -> None: assert state.slot <= attestation.data.slot + SLOTS_PER_EPOCH # Can't submit attestations too quickly assert attestation.data.slot + MIN_ATTESTATION_INCLUSION_DELAY <= state.slot - # Verify that the justified epoch is correct, case 1: current epoch attestations + # Verify that the justified epoch/root is correct if slot_to_epoch(attestation.data.slot) >= get_current_epoch(state): + # Case 1: current epoch attestations assert attestation.data.justified_epoch == state.justified_epoch - # Case 2: previous epoch attestations + assert attestation.data.justified_block_root == state.justified_root else: + # Case 2: previous epoch attestations assert attestation.data.justified_epoch == state.previous_justified_epoch - # Check that the justified block root is correct - assert attestation.data.justified_block_root == get_block_root( - state, get_epoch_start_slot(attestation.data.justified_epoch) - ) + assert attestation.data.justified_block_root == state.previous_justified_root # Check that the crosslink data is valid acceptable_crosslink_data = { # Case 1: Latest crosslink matches the one in the state