plugeth/les/catalyst/api.go

190 lines
7.1 KiB
Go

// Copyright 2022 The go-ethereum Authors
// This file is part of the go-ethereum library.
//
// The go-ethereum library is free software: you can redistribute it and/or modify
// it under the terms of the GNU Lesser General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// The go-ethereum library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU Lesser General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public License
// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
// Package catalyst implements the temporary eth1/eth2 RPC integration.
package catalyst
import (
"errors"
"fmt"
"github.com/ethereum/go-ethereum/common"
"github.com/ethereum/go-ethereum/core/beacon"
"github.com/ethereum/go-ethereum/les"
"github.com/ethereum/go-ethereum/log"
"github.com/ethereum/go-ethereum/node"
"github.com/ethereum/go-ethereum/rpc"
)
// Register adds catalyst APIs to the light client.
func Register(stack *node.Node, backend *les.LightEthereum) error {
log.Warn("Catalyst mode enabled", "protocol", "les")
stack.RegisterAPIs([]rpc.API{
{
Namespace: "engine",
Version: "1.0",
Service: NewConsensusAPI(backend),
Public: true,
Authenticated: true,
},
})
return nil
}
type ConsensusAPI struct {
les *les.LightEthereum
}
// NewConsensusAPI creates a new consensus api for the given backend.
// The underlying blockchain needs to have a valid terminal total difficulty set.
func NewConsensusAPI(les *les.LightEthereum) *ConsensusAPI {
if les.BlockChain().Config().TerminalTotalDifficulty == nil {
panic("Catalyst started without valid total difficulty")
}
return &ConsensusAPI{les: les}
}
// ForkchoiceUpdatedV1 has several responsibilities:
// If the method is called with an empty head block:
// we return success, which can be used to check if the catalyst mode is enabled
// If the total difficulty was not reached:
// we return INVALID
// If the finalizedBlockHash is set:
// we check if we have the finalizedBlockHash in our db, if not we start a sync
// We try to set our blockchain to the headBlock
// If there are payloadAttributes:
// we return an error since block creation is not supported in les mode
func (api *ConsensusAPI) ForkchoiceUpdatedV1(heads beacon.ForkchoiceStateV1, payloadAttributes *beacon.PayloadAttributesV1) (beacon.ForkChoiceResponse, error) {
if heads.HeadBlockHash == (common.Hash{}) {
log.Warn("Forkchoice requested update to zero hash")
return beacon.STATUS_INVALID, nil // TODO(karalabe): Why does someone send us this?
}
if err := api.checkTerminalTotalDifficulty(heads.HeadBlockHash); err != nil {
if header := api.les.BlockChain().GetHeaderByHash(heads.HeadBlockHash); header == nil {
// TODO (MariusVanDerWijden) trigger sync
return beacon.STATUS_SYNCING, nil
}
return beacon.STATUS_INVALID, err
}
// If the finalized block is set, check if it is in our blockchain
if heads.FinalizedBlockHash != (common.Hash{}) {
if header := api.les.BlockChain().GetHeaderByHash(heads.FinalizedBlockHash); header == nil {
// TODO (MariusVanDerWijden) trigger sync
return beacon.STATUS_SYNCING, nil
}
}
// SetHead
if err := api.setCanonical(heads.HeadBlockHash); err != nil {
return beacon.STATUS_INVALID, err
}
if payloadAttributes != nil {
return beacon.STATUS_INVALID, errors.New("not supported")
}
return api.validForkChoiceResponse(), nil
}
// GetPayloadV1 returns a cached payload by id. It's not supported in les mode.
func (api *ConsensusAPI) GetPayloadV1(payloadID beacon.PayloadID) (*beacon.ExecutableDataV1, error) {
return nil, beacon.GenericServerError.With(errors.New("not supported in light client mode"))
}
// ExecutePayloadV1 creates an Eth1 block, inserts it in the chain, and returns the status of the chain.
func (api *ConsensusAPI) ExecutePayloadV1(params beacon.ExecutableDataV1) (beacon.PayloadStatusV1, error) {
block, err := beacon.ExecutableDataToBlock(params)
if err != nil {
return api.invalid(), err
}
if !api.les.BlockChain().HasHeader(block.ParentHash(), block.NumberU64()-1) {
/*
TODO (MariusVanDerWijden) reenable once sync is merged
if err := api.eth.Downloader().BeaconSync(api.eth.SyncMode(), block.Header()); err != nil {
return SYNCING, err
}
*/
// TODO (MariusVanDerWijden) we should return nil here not empty hash
return beacon.PayloadStatusV1{Status: beacon.SYNCING, LatestValidHash: nil}, nil
}
parent := api.les.BlockChain().GetHeaderByHash(params.ParentHash)
if parent == nil {
return api.invalid(), fmt.Errorf("could not find parent %x", params.ParentHash)
}
td := api.les.BlockChain().GetTd(parent.Hash(), block.NumberU64()-1)
ttd := api.les.BlockChain().Config().TerminalTotalDifficulty
if td.Cmp(ttd) < 0 {
return api.invalid(), fmt.Errorf("can not execute payload on top of block with low td got: %v threshold %v", td, ttd)
}
if err = api.les.BlockChain().InsertHeader(block.Header()); err != nil {
return api.invalid(), err
}
if merger := api.les.Merger(); !merger.TDDReached() {
merger.ReachTTD()
}
hash := block.Hash()
return beacon.PayloadStatusV1{Status: beacon.VALID, LatestValidHash: &hash}, nil
}
func (api *ConsensusAPI) validForkChoiceResponse() beacon.ForkChoiceResponse {
currentHash := api.les.BlockChain().CurrentHeader().Hash()
return beacon.ForkChoiceResponse{
PayloadStatus: beacon.PayloadStatusV1{Status: beacon.VALID, LatestValidHash: &currentHash},
}
}
// invalid returns a response "INVALID" with the latest valid hash set to the current head.
func (api *ConsensusAPI) invalid() beacon.PayloadStatusV1 {
currentHash := api.les.BlockChain().CurrentHeader().Hash()
return beacon.PayloadStatusV1{Status: beacon.INVALID, LatestValidHash: &currentHash}
}
func (api *ConsensusAPI) checkTerminalTotalDifficulty(head common.Hash) error {
// shortcut if we entered PoS already
if api.les.Merger().PoSFinalized() {
return nil
}
// make sure the parent has enough terminal total difficulty
header := api.les.BlockChain().GetHeaderByHash(head)
if header == nil {
return errors.New("unknown header")
}
td := api.les.BlockChain().GetTd(header.Hash(), header.Number.Uint64())
if td != nil && td.Cmp(api.les.BlockChain().Config().TerminalTotalDifficulty) < 0 {
return errors.New("invalid ttd")
}
return nil
}
// setCanonical is called to perform a force choice.
func (api *ConsensusAPI) setCanonical(newHead common.Hash) error {
log.Info("Setting head", "head", newHead)
headHeader := api.les.BlockChain().CurrentHeader()
if headHeader.Hash() == newHead {
return nil
}
newHeadHeader := api.les.BlockChain().GetHeaderByHash(newHead)
if newHeadHeader == nil {
return errors.New("unknown header")
}
if err := api.les.BlockChain().SetCanonical(newHeadHeader); err != nil {
return err
}
// Trigger the transition if it's the first `NewHead` event.
if merger := api.les.Merger(); !merger.PoSFinalized() {
merger.FinalizePoS()
}
return nil
}