nimbus-eth1/fluffy/network/beacon/beacon_chain_historical_sum...

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1.9 KiB
Nim

# fluffy
# Copyright (c) 2023-2024 Status Research & Development GmbH
# Licensed and distributed under either of
# * MIT license (license terms in the root directory or at https://opensource.org/licenses/MIT).
# * Apache v2 license (license terms in the root directory or at https://www.apache.org/licenses/LICENSE-2.0).
# at your option. This file may not be copied, modified, or distributed except according to those terms.
#
# Example of how the beacon state historical_summaries field could be provided
# with a Merkle proof that can be verified against the right beacon state root.
# These historical_summaries with their proof could for example be provided over
# the network and verified on the receivers end.
#
{.push raises: [].}
import stew/results, beacon_chain/spec/forks, beacon_chain/spec/datatypes/capella
export results
type
HistoricalSummaries* = HashList[HistoricalSummary, Limit HISTORICAL_ROOTS_LIMIT]
HistoricalSummariesProof* = array[5, Digest]
HistoricalSummariesWithProof* = object
finalized_slot*: Slot
historical_summaries*: HistoricalSummaries
proof*: HistoricalSummariesProof
func buildProof*(
state: ForkedHashedBeaconState
): Result[HistoricalSummariesProof, string] =
let gIndex = GeneralizedIndex(59) # 31 + 28 = 59
var proof: HistoricalSummariesProof
withState(state):
?forkyState.data.build_proof(gIndex, proof)
ok(proof)
func verifyProof*(
historical_summaries: HistoricalSummaries,
proof: HistoricalSummariesProof,
stateRoot: Digest,
): bool =
let
gIndex = GeneralizedIndex(59)
leave = hash_tree_root(historical_summaries)
verify_merkle_multiproof(@[leave], proof, @[gIndex], stateRoot)
func verifyProof*(
summariesWithProof: HistoricalSummariesWithProof, stateRoot: Digest
): bool =
verifyProof(
summariesWithProof.historical_summaries, summariesWithProof.proof, stateRoot
)