plugeth/eth/handler_eth.go
Péter Szilágyi 8afbcf4713
eth: enforce announcement metadatas and drop peers violating the protocol (#28261)
* eth: enforce announcement metadatas and drop peers violating the protocol

* eth/fetcher: relax eth/68 validation a bit for flakey clients

* tests/fuzzers/txfetcher: pull in suggestion from Marius

* eth/fetcher: add tests for peer dropping

* eth/fetcher: linter linter linter linter linter
2023-10-10 11:35:51 +03:00

143 lines
5.0 KiB
Go

// Copyright 2020 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 eth
import (
"errors"
"fmt"
"math/big"
"time"
"github.com/ethereum/go-ethereum/common"
"github.com/ethereum/go-ethereum/core"
"github.com/ethereum/go-ethereum/core/types"
"github.com/ethereum/go-ethereum/eth/protocols/eth"
"github.com/ethereum/go-ethereum/p2p/enode"
)
// ethHandler implements the eth.Backend interface to handle the various network
// packets that are sent as replies or broadcasts.
type ethHandler handler
func (h *ethHandler) Chain() *core.BlockChain { return h.chain }
func (h *ethHandler) TxPool() eth.TxPool { return h.txpool }
// RunPeer is invoked when a peer joins on the `eth` protocol.
func (h *ethHandler) RunPeer(peer *eth.Peer, hand eth.Handler) error {
return (*handler)(h).runEthPeer(peer, hand)
}
// PeerInfo retrieves all known `eth` information about a peer.
func (h *ethHandler) PeerInfo(id enode.ID) interface{} {
if p := h.peers.peer(id.String()); p != nil {
return p.info()
}
return nil
}
// AcceptTxs retrieves whether transaction processing is enabled on the node
// or if inbound transactions should simply be dropped.
func (h *ethHandler) AcceptTxs() bool {
return h.synced.Load()
}
// Handle is invoked from a peer's message handler when it receives a new remote
// message that the handler couldn't consume and serve itself.
func (h *ethHandler) Handle(peer *eth.Peer, packet eth.Packet) error {
// Consume any broadcasts and announces, forwarding the rest to the downloader
switch packet := packet.(type) {
case *eth.NewBlockHashesPacket:
hashes, numbers := packet.Unpack()
return h.handleBlockAnnounces(peer, hashes, numbers)
case *eth.NewBlockPacket:
return h.handleBlockBroadcast(peer, packet.Block, packet.TD)
case *eth.NewPooledTransactionHashesPacket67:
return h.txFetcher.Notify(peer.ID(), nil, nil, *packet)
case *eth.NewPooledTransactionHashesPacket68:
return h.txFetcher.Notify(peer.ID(), packet.Types, packet.Sizes, packet.Hashes)
case *eth.TransactionsPacket:
for _, tx := range *packet {
if tx.Type() == types.BlobTxType {
return errors.New("disallowed broadcast blob transaction")
}
}
return h.txFetcher.Enqueue(peer.ID(), *packet, false)
case *eth.PooledTransactionsResponse:
return h.txFetcher.Enqueue(peer.ID(), *packet, true)
default:
return fmt.Errorf("unexpected eth packet type: %T", packet)
}
}
// handleBlockAnnounces is invoked from a peer's message handler when it transmits a
// batch of block announcements for the local node to process.
func (h *ethHandler) handleBlockAnnounces(peer *eth.Peer, hashes []common.Hash, numbers []uint64) error {
// Drop all incoming block announces from the p2p network if
// the chain already entered the pos stage and disconnect the
// remote peer.
if h.merger.PoSFinalized() {
return errors.New("disallowed block announcement")
}
// Schedule all the unknown hashes for retrieval
var (
unknownHashes = make([]common.Hash, 0, len(hashes))
unknownNumbers = make([]uint64, 0, len(numbers))
)
for i := 0; i < len(hashes); i++ {
if !h.chain.HasBlock(hashes[i], numbers[i]) {
unknownHashes = append(unknownHashes, hashes[i])
unknownNumbers = append(unknownNumbers, numbers[i])
}
}
for i := 0; i < len(unknownHashes); i++ {
h.blockFetcher.Notify(peer.ID(), unknownHashes[i], unknownNumbers[i], time.Now(), peer.RequestOneHeader, peer.RequestBodies)
}
return nil
}
// handleBlockBroadcast is invoked from a peer's message handler when it transmits a
// block broadcast for the local node to process.
func (h *ethHandler) handleBlockBroadcast(peer *eth.Peer, block *types.Block, td *big.Int) error {
// Drop all incoming block announces from the p2p network if
// the chain already entered the pos stage and disconnect the
// remote peer.
if h.merger.PoSFinalized() {
return errors.New("disallowed block broadcast")
}
// Schedule the block for import
h.blockFetcher.Enqueue(peer.ID(), block)
// Assuming the block is importable by the peer, but possibly not yet done so,
// calculate the head hash and TD that the peer truly must have.
var (
trueHead = block.ParentHash()
trueTD = new(big.Int).Sub(td, block.Difficulty())
)
// Update the peer's total difficulty if better than the previous
if _, td := peer.Head(); trueTD.Cmp(td) > 0 {
peer.SetHead(trueHead, trueTD)
h.chainSync.handlePeerEvent()
}
return nil
}