plugeth/les/server.go
b00ris 769657060e les: implement ultralight client (#16904)
For more information about this light client mode, read
https://hackmd.io/s/HJy7jjZpm
2019-01-24 12:18:26 +01:00

404 lines
10 KiB
Go

// Copyright 2016 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 les implements the Light Ethereum Subprotocol.
package les
import (
"crypto/ecdsa"
"encoding/binary"
"math"
"sync"
"github.com/ethereum/go-ethereum/common"
"github.com/ethereum/go-ethereum/core"
"github.com/ethereum/go-ethereum/core/rawdb"
"github.com/ethereum/go-ethereum/core/types"
"github.com/ethereum/go-ethereum/eth"
"github.com/ethereum/go-ethereum/ethdb"
"github.com/ethereum/go-ethereum/les/flowcontrol"
"github.com/ethereum/go-ethereum/light"
"github.com/ethereum/go-ethereum/log"
"github.com/ethereum/go-ethereum/p2p"
"github.com/ethereum/go-ethereum/p2p/discv5"
"github.com/ethereum/go-ethereum/params"
"github.com/ethereum/go-ethereum/rlp"
)
type LesServer struct {
lesCommons
fcManager *flowcontrol.ClientManager // nil if our node is client only
fcCostStats *requestCostStats
defParams *flowcontrol.ServerParams
lesTopics []discv5.Topic
privateKey *ecdsa.PrivateKey
quitSync chan struct{}
onlyAnnounce bool
}
func NewLesServer(eth *eth.Ethereum, config *eth.Config) (*LesServer, error) {
quitSync := make(chan struct{})
pm, err := NewProtocolManager(
eth.BlockChain().Config(),
light.DefaultServerIndexerConfig,
false,
config.NetworkId,
eth.EventMux(),
eth.Engine(),
newPeerSet(),
eth.BlockChain(),
eth.TxPool(),
eth.ChainDb(),
nil,
nil,
nil,
quitSync,
new(sync.WaitGroup),
config.ULC)
if err != nil {
return nil, err
}
lesTopics := make([]discv5.Topic, len(AdvertiseProtocolVersions))
for i, pv := range AdvertiseProtocolVersions {
lesTopics[i] = lesTopic(eth.BlockChain().Genesis().Hash(), pv)
}
srv := &LesServer{
lesCommons: lesCommons{
config: config,
chainDb: eth.ChainDb(),
iConfig: light.DefaultServerIndexerConfig,
chtIndexer: light.NewChtIndexer(eth.ChainDb(), nil, params.CHTFrequencyServer, params.HelperTrieProcessConfirmations),
bloomTrieIndexer: light.NewBloomTrieIndexer(eth.ChainDb(), nil, params.BloomBitsBlocks, params.BloomTrieFrequency),
protocolManager: pm,
},
quitSync: quitSync,
lesTopics: lesTopics,
onlyAnnounce: config.OnlyAnnounce,
}
logger := log.New()
chtV1SectionCount, _, _ := srv.chtIndexer.Sections() // indexer still uses LES/1 4k section size for backwards server compatibility
chtV2SectionCount := chtV1SectionCount / (params.CHTFrequencyClient / params.CHTFrequencyServer)
if chtV2SectionCount != 0 {
// convert to LES/2 section
chtLastSection := chtV2SectionCount - 1
// convert last LES/2 section index back to LES/1 index for chtIndexer.SectionHead
chtLastSectionV1 := (chtLastSection+1)*(params.CHTFrequencyClient/params.CHTFrequencyServer) - 1
chtSectionHead := srv.chtIndexer.SectionHead(chtLastSectionV1)
chtRoot := light.GetChtRoot(pm.chainDb, chtLastSectionV1, chtSectionHead)
logger.Info("Loaded CHT", "section", chtLastSection, "head", chtSectionHead, "root", chtRoot)
}
bloomTrieSectionCount, _, _ := srv.bloomTrieIndexer.Sections()
if bloomTrieSectionCount != 0 {
bloomTrieLastSection := bloomTrieSectionCount - 1
bloomTrieSectionHead := srv.bloomTrieIndexer.SectionHead(bloomTrieLastSection)
bloomTrieRoot := light.GetBloomTrieRoot(pm.chainDb, bloomTrieLastSection, bloomTrieSectionHead)
logger.Info("Loaded bloom trie", "section", bloomTrieLastSection, "head", bloomTrieSectionHead, "root", bloomTrieRoot)
}
srv.chtIndexer.Start(eth.BlockChain())
pm.server = srv
srv.defParams = &flowcontrol.ServerParams{
BufLimit: 300000000,
MinRecharge: 50000,
}
srv.fcManager = flowcontrol.NewClientManager(uint64(config.LightServ), 10, 1000000000)
srv.fcCostStats = newCostStats(eth.ChainDb())
return srv, nil
}
func (s *LesServer) Protocols() []p2p.Protocol {
return s.makeProtocols(ServerProtocolVersions)
}
// Start starts the LES server
func (s *LesServer) Start(srvr *p2p.Server) {
s.protocolManager.Start(s.config.LightPeers)
if srvr.DiscV5 != nil {
for _, topic := range s.lesTopics {
topic := topic
go func() {
logger := log.New("topic", topic)
logger.Info("Starting topic registration")
defer logger.Info("Terminated topic registration")
srvr.DiscV5.RegisterTopic(topic, s.quitSync)
}()
}
}
s.privateKey = srvr.PrivateKey
s.protocolManager.blockLoop()
}
func (s *LesServer) SetBloomBitsIndexer(bloomIndexer *core.ChainIndexer) {
bloomIndexer.AddChildIndexer(s.bloomTrieIndexer)
}
// Stop stops the LES service
func (s *LesServer) Stop() {
s.chtIndexer.Close()
// bloom trie indexer is closed by parent bloombits indexer
s.fcCostStats.store()
s.fcManager.Stop()
go func() {
<-s.protocolManager.noMorePeers
}()
s.protocolManager.Stop()
}
type requestCosts struct {
baseCost, reqCost uint64
}
type requestCostTable map[uint64]*requestCosts
type RequestCostList []struct {
MsgCode, BaseCost, ReqCost uint64
}
func (list RequestCostList) decode() requestCostTable {
table := make(requestCostTable)
for _, e := range list {
table[e.MsgCode] = &requestCosts{
baseCost: e.BaseCost,
reqCost: e.ReqCost,
}
}
return table
}
type linReg struct {
sumX, sumY, sumXX, sumXY float64
cnt uint64
}
const linRegMaxCnt = 100000
func (l *linReg) add(x, y float64) {
if l.cnt >= linRegMaxCnt {
sub := float64(l.cnt+1-linRegMaxCnt) / linRegMaxCnt
l.sumX -= l.sumX * sub
l.sumY -= l.sumY * sub
l.sumXX -= l.sumXX * sub
l.sumXY -= l.sumXY * sub
l.cnt = linRegMaxCnt - 1
}
l.cnt++
l.sumX += x
l.sumY += y
l.sumXX += x * x
l.sumXY += x * y
}
func (l *linReg) calc() (b, m float64) {
if l.cnt == 0 {
return 0, 0
}
cnt := float64(l.cnt)
d := cnt*l.sumXX - l.sumX*l.sumX
if d < 0.001 {
return l.sumY / cnt, 0
}
m = (cnt*l.sumXY - l.sumX*l.sumY) / d
b = (l.sumY / cnt) - (m * l.sumX / cnt)
return b, m
}
func (l *linReg) toBytes() []byte {
var arr [40]byte
binary.BigEndian.PutUint64(arr[0:8], math.Float64bits(l.sumX))
binary.BigEndian.PutUint64(arr[8:16], math.Float64bits(l.sumY))
binary.BigEndian.PutUint64(arr[16:24], math.Float64bits(l.sumXX))
binary.BigEndian.PutUint64(arr[24:32], math.Float64bits(l.sumXY))
binary.BigEndian.PutUint64(arr[32:40], l.cnt)
return arr[:]
}
func linRegFromBytes(data []byte) *linReg {
if len(data) != 40 {
return nil
}
l := &linReg{}
l.sumX = math.Float64frombits(binary.BigEndian.Uint64(data[0:8]))
l.sumY = math.Float64frombits(binary.BigEndian.Uint64(data[8:16]))
l.sumXX = math.Float64frombits(binary.BigEndian.Uint64(data[16:24]))
l.sumXY = math.Float64frombits(binary.BigEndian.Uint64(data[24:32]))
l.cnt = binary.BigEndian.Uint64(data[32:40])
return l
}
type requestCostStats struct {
lock sync.RWMutex
db ethdb.Database
stats map[uint64]*linReg
}
type requestCostStatsRlp []struct {
MsgCode uint64
Data []byte
}
var rcStatsKey = []byte("_requestCostStats")
func newCostStats(db ethdb.Database) *requestCostStats {
stats := make(map[uint64]*linReg)
for _, code := range reqList {
stats[code] = &linReg{cnt: 100}
}
if db != nil {
data, err := db.Get(rcStatsKey)
var statsRlp requestCostStatsRlp
if err == nil {
err = rlp.DecodeBytes(data, &statsRlp)
}
if err == nil {
for _, r := range statsRlp {
if stats[r.MsgCode] != nil {
if l := linRegFromBytes(r.Data); l != nil {
stats[r.MsgCode] = l
}
}
}
}
}
return &requestCostStats{
db: db,
stats: stats,
}
}
func (s *requestCostStats) store() {
s.lock.Lock()
defer s.lock.Unlock()
statsRlp := make(requestCostStatsRlp, len(reqList))
for i, code := range reqList {
statsRlp[i].MsgCode = code
statsRlp[i].Data = s.stats[code].toBytes()
}
if data, err := rlp.EncodeToBytes(statsRlp); err == nil {
s.db.Put(rcStatsKey, data)
}
}
func (s *requestCostStats) getCurrentList() RequestCostList {
s.lock.Lock()
defer s.lock.Unlock()
list := make(RequestCostList, len(reqList))
for idx, code := range reqList {
b, m := s.stats[code].calc()
if m < 0 {
b += m
m = 0
}
if b < 0 {
b = 0
}
list[idx].MsgCode = code
list[idx].BaseCost = uint64(b * 2)
list[idx].ReqCost = uint64(m * 2)
}
return list
}
func (s *requestCostStats) update(msgCode, reqCnt, cost uint64) {
s.lock.Lock()
defer s.lock.Unlock()
c, ok := s.stats[msgCode]
if !ok || reqCnt == 0 {
return
}
c.add(float64(reqCnt), float64(cost))
}
func (pm *ProtocolManager) blockLoop() {
pm.wg.Add(1)
headCh := make(chan core.ChainHeadEvent, 10)
headSub := pm.blockchain.SubscribeChainHeadEvent(headCh)
go func() {
var lastHead *types.Header
lastBroadcastTd := common.Big0
for {
select {
case ev := <-headCh:
peers := pm.peers.AllPeers()
if len(peers) > 0 {
header := ev.Block.Header()
hash := header.Hash()
number := header.Number.Uint64()
td := rawdb.ReadTd(pm.chainDb, hash, number)
if td != nil && td.Cmp(lastBroadcastTd) > 0 {
var reorg uint64
if lastHead != nil {
reorg = lastHead.Number.Uint64() - rawdb.FindCommonAncestor(pm.chainDb, header, lastHead).Number.Uint64()
}
lastHead = header
lastBroadcastTd = td
log.Debug("Announcing block to peers", "number", number, "hash", hash, "td", td, "reorg", reorg)
announce := announceData{Hash: hash, Number: number, Td: td, ReorgDepth: reorg}
var (
signed bool
signedAnnounce announceData
)
for _, p := range peers {
switch p.announceType {
case announceTypeSimple:
select {
case p.announceChn <- announce:
default:
pm.removePeer(p.id)
}
case announceTypeSigned:
if !signed {
signedAnnounce = announce
signedAnnounce.sign(pm.server.privateKey)
signed = true
}
select {
case p.announceChn <- signedAnnounce:
default:
pm.removePeer(p.id)
}
}
}
}
}
case <-pm.quitSync:
headSub.Unsubscribe()
pm.wg.Done()
return
}
}
}()
}