Files
go-ethereum/eth/protocols/eth/handler.go
Péter Szilágyi e3430ac7df eth: check snap satelliteness, delegate drop to eth (#22235)
* eth: check snap satelliteness, delegate drop to eth

* eth: better handle eth/snap satellite relation, merge reg/unreg paths
2021-02-02 10:44:36 +02:00

513 lines
17 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 (
"encoding/json"
"fmt"
"math/big"
"github.com/ethereum/go-ethereum/common"
"github.com/ethereum/go-ethereum/core"
"github.com/ethereum/go-ethereum/core/types"
"github.com/ethereum/go-ethereum/log"
"github.com/ethereum/go-ethereum/p2p"
"github.com/ethereum/go-ethereum/p2p/enode"
"github.com/ethereum/go-ethereum/p2p/enr"
"github.com/ethereum/go-ethereum/params"
"github.com/ethereum/go-ethereum/rlp"
"github.com/ethereum/go-ethereum/trie"
)
const (
// softResponseLimit is the target maximum size of replies to data retrievals.
softResponseLimit = 2 * 1024 * 1024
// estHeaderSize is the approximate size of an RLP encoded block header.
estHeaderSize = 500
// maxHeadersServe is the maximum number of block headers to serve. This number
// is there to limit the number of disk lookups.
maxHeadersServe = 1024
// maxBodiesServe is the maximum number of block bodies to serve. This number
// is mostly there to limit the number of disk lookups. With 24KB block sizes
// nowadays, the practical limit will always be softResponseLimit.
maxBodiesServe = 1024
// maxNodeDataServe is the maximum number of state trie nodes to serve. This
// number is there to limit the number of disk lookups.
maxNodeDataServe = 1024
// maxReceiptsServe is the maximum number of block receipts to serve. This
// number is mostly there to limit the number of disk lookups. With block
// containing 200+ transactions nowadays, the practical limit will always
// be softResponseLimit.
maxReceiptsServe = 1024
)
// Handler is a callback to invoke from an outside runner after the boilerplate
// exchanges have passed.
type Handler func(peer *Peer) error
// Backend defines the data retrieval methods to serve remote requests and the
// callback methods to invoke on remote deliveries.
type Backend interface {
// Chain retrieves the blockchain object to serve data.
Chain() *core.BlockChain
// StateBloom retrieves the bloom filter - if any - for state trie nodes.
StateBloom() *trie.SyncBloom
// TxPool retrieves the transaction pool object to serve data.
TxPool() TxPool
// AcceptTxs retrieves whether transaction processing is enabled on the node
// or if inbound transactions should simply be dropped.
AcceptTxs() bool
// RunPeer is invoked when a peer joins on the `eth` protocol. The handler
// should do any peer maintenance work, handshakes and validations. If all
// is passed, control should be given back to the `handler` to process the
// inbound messages going forward.
RunPeer(peer *Peer, handler Handler) error
// PeerInfo retrieves all known `eth` information about a peer.
PeerInfo(id enode.ID) interface{}
// Handle is a callback to be invoked when a data packet is received from
// the remote peer. Only packets not consumed by the protocol handler will
// be forwarded to the backend.
Handle(peer *Peer, packet Packet) error
}
// TxPool defines the methods needed by the protocol handler to serve transactions.
type TxPool interface {
// Get retrieves the the transaction from the local txpool with the given hash.
Get(hash common.Hash) *types.Transaction
}
// MakeProtocols constructs the P2P protocol definitions for `eth`.
func MakeProtocols(backend Backend, network uint64, dnsdisc enode.Iterator) []p2p.Protocol {
protocols := make([]p2p.Protocol, len(ProtocolVersions))
for i, version := range ProtocolVersions {
version := version // Closure
protocols[i] = p2p.Protocol{
Name: ProtocolName,
Version: version,
Length: protocolLengths[version],
Run: func(p *p2p.Peer, rw p2p.MsgReadWriter) error {
peer := NewPeer(version, p, rw, backend.TxPool())
defer peer.Close()
return backend.RunPeer(peer, func(peer *Peer) error {
return Handle(backend, peer)
})
},
NodeInfo: func() interface{} {
return nodeInfo(backend.Chain(), network)
},
PeerInfo: func(id enode.ID) interface{} {
return backend.PeerInfo(id)
},
Attributes: []enr.Entry{currentENREntry(backend.Chain())},
DialCandidates: dnsdisc,
}
}
return protocols
}
// NodeInfo represents a short summary of the `eth` sub-protocol metadata
// known about the host peer.
type NodeInfo struct {
Network uint64 `json:"network"` // Ethereum network ID (1=Frontier, 2=Morden, Ropsten=3, Rinkeby=4)
Difficulty *big.Int `json:"difficulty"` // Total difficulty of the host's blockchain
Genesis common.Hash `json:"genesis"` // SHA3 hash of the host's genesis block
Config *params.ChainConfig `json:"config"` // Chain configuration for the fork rules
Head common.Hash `json:"head"` // Hex hash of the host's best owned block
}
// nodeInfo retrieves some `eth` protocol metadata about the running host node.
func nodeInfo(chain *core.BlockChain, network uint64) *NodeInfo {
head := chain.CurrentBlock()
return &NodeInfo{
Network: network,
Difficulty: chain.GetTd(head.Hash(), head.NumberU64()),
Genesis: chain.Genesis().Hash(),
Config: chain.Config(),
Head: head.Hash(),
}
}
// Handle is invoked whenever an `eth` connection is made that successfully passes
// the protocol handshake. This method will keep processing messages until the
// connection is torn down.
func Handle(backend Backend, peer *Peer) error {
for {
if err := handleMessage(backend, peer); err != nil {
peer.Log().Debug("Message handling failed in `eth`", "err", err)
return err
}
}
}
// handleMessage is invoked whenever an inbound message is received from a remote
// peer. The remote connection is torn down upon returning any error.
func handleMessage(backend Backend, peer *Peer) error {
// Read the next message from the remote peer, and ensure it's fully consumed
msg, err := peer.rw.ReadMsg()
if err != nil {
return err
}
if msg.Size > maxMessageSize {
return fmt.Errorf("%w: %v > %v", errMsgTooLarge, msg.Size, maxMessageSize)
}
defer msg.Discard()
// Handle the message depending on its contents
switch {
case msg.Code == StatusMsg:
// Status messages should never arrive after the handshake
return fmt.Errorf("%w: uncontrolled status message", errExtraStatusMsg)
// Block header query, collect the requested headers and reply
case msg.Code == GetBlockHeadersMsg:
// Decode the complex header query
var query GetBlockHeadersPacket
if err := msg.Decode(&query); err != nil {
return fmt.Errorf("%w: message %v: %v", errDecode, msg, err)
}
hashMode := query.Origin.Hash != (common.Hash{})
first := true
maxNonCanonical := uint64(100)
// Gather headers until the fetch or network limits is reached
var (
bytes common.StorageSize
headers []*types.Header
unknown bool
lookups int
)
for !unknown && len(headers) < int(query.Amount) && bytes < softResponseLimit &&
len(headers) < maxHeadersServe && lookups < 2*maxHeadersServe {
lookups++
// Retrieve the next header satisfying the query
var origin *types.Header
if hashMode {
if first {
first = false
origin = backend.Chain().GetHeaderByHash(query.Origin.Hash)
if origin != nil {
query.Origin.Number = origin.Number.Uint64()
}
} else {
origin = backend.Chain().GetHeader(query.Origin.Hash, query.Origin.Number)
}
} else {
origin = backend.Chain().GetHeaderByNumber(query.Origin.Number)
}
if origin == nil {
break
}
headers = append(headers, origin)
bytes += estHeaderSize
// Advance to the next header of the query
switch {
case hashMode && query.Reverse:
// Hash based traversal towards the genesis block
ancestor := query.Skip + 1
if ancestor == 0 {
unknown = true
} else {
query.Origin.Hash, query.Origin.Number = backend.Chain().GetAncestor(query.Origin.Hash, query.Origin.Number, ancestor, &maxNonCanonical)
unknown = (query.Origin.Hash == common.Hash{})
}
case hashMode && !query.Reverse:
// Hash based traversal towards the leaf block
var (
current = origin.Number.Uint64()
next = current + query.Skip + 1
)
if next <= current {
infos, _ := json.MarshalIndent(peer.Peer.Info(), "", " ")
peer.Log().Warn("GetBlockHeaders skip overflow attack", "current", current, "skip", query.Skip, "next", next, "attacker", infos)
unknown = true
} else {
if header := backend.Chain().GetHeaderByNumber(next); header != nil {
nextHash := header.Hash()
expOldHash, _ := backend.Chain().GetAncestor(nextHash, next, query.Skip+1, &maxNonCanonical)
if expOldHash == query.Origin.Hash {
query.Origin.Hash, query.Origin.Number = nextHash, next
} else {
unknown = true
}
} else {
unknown = true
}
}
case query.Reverse:
// Number based traversal towards the genesis block
if query.Origin.Number >= query.Skip+1 {
query.Origin.Number -= query.Skip + 1
} else {
unknown = true
}
case !query.Reverse:
// Number based traversal towards the leaf block
query.Origin.Number += query.Skip + 1
}
}
return peer.SendBlockHeaders(headers)
case msg.Code == BlockHeadersMsg:
// A batch of headers arrived to one of our previous requests
res := new(BlockHeadersPacket)
if err := msg.Decode(res); err != nil {
return fmt.Errorf("%w: message %v: %v", errDecode, msg, err)
}
return backend.Handle(peer, res)
case msg.Code == GetBlockBodiesMsg:
// Decode the block body retrieval message
var query GetBlockBodiesPacket
if err := msg.Decode(&query); err != nil {
return fmt.Errorf("%w: message %v: %v", errDecode, msg, err)
}
// Gather blocks until the fetch or network limits is reached
var (
bytes int
bodies []rlp.RawValue
)
for lookups, hash := range query {
if bytes >= softResponseLimit || len(bodies) >= maxBodiesServe ||
lookups >= 2*maxBodiesServe {
break
}
if data := backend.Chain().GetBodyRLP(hash); len(data) != 0 {
bodies = append(bodies, data)
bytes += len(data)
}
}
return peer.SendBlockBodiesRLP(bodies)
case msg.Code == BlockBodiesMsg:
// A batch of block bodies arrived to one of our previous requests
res := new(BlockBodiesPacket)
if err := msg.Decode(res); err != nil {
return fmt.Errorf("%w: message %v: %v", errDecode, msg, err)
}
return backend.Handle(peer, res)
case msg.Code == GetNodeDataMsg:
// Decode the trie node data retrieval message
var query GetNodeDataPacket
if err := msg.Decode(&query); err != nil {
return fmt.Errorf("%w: message %v: %v", errDecode, msg, err)
}
// Gather state data until the fetch or network limits is reached
var (
bytes int
nodes [][]byte
)
for lookups, hash := range query {
if bytes >= softResponseLimit || len(nodes) >= maxNodeDataServe ||
lookups >= 2*maxNodeDataServe {
break
}
// Retrieve the requested state entry
if bloom := backend.StateBloom(); bloom != nil && !bloom.Contains(hash[:]) {
// Only lookup the trie node if there's chance that we actually have it
continue
}
entry, err := backend.Chain().TrieNode(hash)
if len(entry) == 0 || err != nil {
// Read the contract code with prefix only to save unnecessary lookups.
entry, err = backend.Chain().ContractCodeWithPrefix(hash)
}
if err == nil && len(entry) > 0 {
nodes = append(nodes, entry)
bytes += len(entry)
}
}
return peer.SendNodeData(nodes)
case msg.Code == NodeDataMsg:
// A batch of node state data arrived to one of our previous requests
res := new(NodeDataPacket)
if err := msg.Decode(res); err != nil {
return fmt.Errorf("%w: message %v: %v", errDecode, msg, err)
}
return backend.Handle(peer, res)
case msg.Code == GetReceiptsMsg:
// Decode the block receipts retrieval message
var query GetReceiptsPacket
if err := msg.Decode(&query); err != nil {
return fmt.Errorf("%w: message %v: %v", errDecode, msg, err)
}
// Gather state data until the fetch or network limits is reached
var (
bytes int
receipts []rlp.RawValue
)
for lookups, hash := range query {
if bytes >= softResponseLimit || len(receipts) >= maxReceiptsServe ||
lookups >= 2*maxReceiptsServe {
break
}
// Retrieve the requested block's receipts
results := backend.Chain().GetReceiptsByHash(hash)
if results == nil {
if header := backend.Chain().GetHeaderByHash(hash); header == nil || header.ReceiptHash != types.EmptyRootHash {
continue
}
}
// If known, encode and queue for response packet
if encoded, err := rlp.EncodeToBytes(results); err != nil {
log.Error("Failed to encode receipt", "err", err)
} else {
receipts = append(receipts, encoded)
bytes += len(encoded)
}
}
return peer.SendReceiptsRLP(receipts)
case msg.Code == ReceiptsMsg:
// A batch of receipts arrived to one of our previous requests
res := new(ReceiptsPacket)
if err := msg.Decode(res); err != nil {
return fmt.Errorf("%w: message %v: %v", errDecode, msg, err)
}
return backend.Handle(peer, res)
case msg.Code == NewBlockHashesMsg:
// A batch of new block announcements just arrived
ann := new(NewBlockHashesPacket)
if err := msg.Decode(ann); err != nil {
return fmt.Errorf("%w: message %v: %v", errDecode, msg, err)
}
// Mark the hashes as present at the remote node
for _, block := range *ann {
peer.markBlock(block.Hash)
}
// Deliver them all to the backend for queuing
return backend.Handle(peer, ann)
case msg.Code == NewBlockMsg:
// Retrieve and decode the propagated block
ann := new(NewBlockPacket)
if err := msg.Decode(ann); err != nil {
return fmt.Errorf("%w: message %v: %v", errDecode, msg, err)
}
if hash := types.CalcUncleHash(ann.Block.Uncles()); hash != ann.Block.UncleHash() {
log.Warn("Propagated block has invalid uncles", "have", hash, "exp", ann.Block.UncleHash())
break // TODO(karalabe): return error eventually, but wait a few releases
}
if hash := types.DeriveSha(ann.Block.Transactions(), trie.NewStackTrie(nil)); hash != ann.Block.TxHash() {
log.Warn("Propagated block has invalid body", "have", hash, "exp", ann.Block.TxHash())
break // TODO(karalabe): return error eventually, but wait a few releases
}
if err := ann.sanityCheck(); err != nil {
return err
}
ann.Block.ReceivedAt = msg.ReceivedAt
ann.Block.ReceivedFrom = peer
// Mark the peer as owning the block
peer.markBlock(ann.Block.Hash())
return backend.Handle(peer, ann)
case msg.Code == NewPooledTransactionHashesMsg && peer.version >= ETH65:
// New transaction announcement arrived, make sure we have
// a valid and fresh chain to handle them
if !backend.AcceptTxs() {
break
}
ann := new(NewPooledTransactionHashesPacket)
if err := msg.Decode(ann); err != nil {
return fmt.Errorf("%w: message %v: %v", errDecode, msg, err)
}
// Schedule all the unknown hashes for retrieval
for _, hash := range *ann {
peer.markTransaction(hash)
}
return backend.Handle(peer, ann)
case msg.Code == GetPooledTransactionsMsg && peer.version >= ETH65:
// Decode the pooled transactions retrieval message
var query GetPooledTransactionsPacket
if err := msg.Decode(&query); err != nil {
return fmt.Errorf("%w: message %v: %v", errDecode, msg, err)
}
// Gather transactions until the fetch or network limits is reached
var (
bytes int
hashes []common.Hash
txs []rlp.RawValue
)
for _, hash := range query {
if bytes >= softResponseLimit {
break
}
// Retrieve the requested transaction, skipping if unknown to us
tx := backend.TxPool().Get(hash)
if tx == nil {
continue
}
// If known, encode and queue for response packet
if encoded, err := rlp.EncodeToBytes(tx); err != nil {
log.Error("Failed to encode transaction", "err", err)
} else {
hashes = append(hashes, hash)
txs = append(txs, encoded)
bytes += len(encoded)
}
}
return peer.SendPooledTransactionsRLP(hashes, txs)
case msg.Code == TransactionsMsg || (msg.Code == PooledTransactionsMsg && peer.version >= ETH65):
// Transactions arrived, make sure we have a valid and fresh chain to handle them
if !backend.AcceptTxs() {
break
}
// Transactions can be processed, parse all of them and deliver to the pool
var txs []*types.Transaction
if err := msg.Decode(&txs); err != nil {
return fmt.Errorf("%w: message %v: %v", errDecode, msg, err)
}
for i, tx := range txs {
// Validate and mark the remote transaction
if tx == nil {
return fmt.Errorf("%w: transaction %d is nil", errDecode, i)
}
peer.markTransaction(tx.Hash())
}
if msg.Code == PooledTransactionsMsg {
return backend.Handle(peer, (*PooledTransactionsPacket)(&txs))
}
return backend.Handle(peer, (*TransactionsPacket)(&txs))
default:
return fmt.Errorf("%w: %v", errInvalidMsgCode, msg.Code)
}
return nil
}