plugeth/les/lespay/server/clientdb.go

251 lines
7.2 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 server
import (
"bytes"
"encoding/binary"
"time"
"github.com/ethereum/go-ethereum/common"
"github.com/ethereum/go-ethereum/common/mclock"
"github.com/ethereum/go-ethereum/ethdb"
"github.com/ethereum/go-ethereum/les/utils"
"github.com/ethereum/go-ethereum/log"
"github.com/ethereum/go-ethereum/p2p/enode"
"github.com/ethereum/go-ethereum/rlp"
lru "github.com/hashicorp/golang-lru"
)
const (
balanceCacheLimit = 8192 // the maximum number of cached items in service token balance queue
// nodeDBVersion is the version identifier of the node data in db
//
// Changelog:
// Version 0 => 1
// * Replace `lastTotal` with `meta` in positive balance: version 0=>1
//
// Version 1 => 2
// * Positive Balance and negative balance is changed:
// * Cumulative time is replaced with expiration
nodeDBVersion = 2
// dbCleanupCycle is the cycle of db for useless data cleanup
dbCleanupCycle = time.Hour
)
var (
positiveBalancePrefix = []byte("pb:") // dbVersion(uint16 big endian) + positiveBalancePrefix + id -> balance
negativeBalancePrefix = []byte("nb:") // dbVersion(uint16 big endian) + negativeBalancePrefix + ip -> balance
expirationKey = []byte("expiration:") // dbVersion(uint16 big endian) + expirationKey -> posExp, negExp
)
type nodeDB struct {
db ethdb.KeyValueStore
cache *lru.Cache
auxbuf []byte // 37-byte auxiliary buffer for key encoding
verbuf [2]byte // 2-byte auxiliary buffer for db version
evictCallBack func(mclock.AbsTime, bool, utils.ExpiredValue) bool // Callback to determine whether the balance can be evicted.
clock mclock.Clock
closeCh chan struct{}
cleanupHook func() // Test hook used for testing
}
func newNodeDB(db ethdb.KeyValueStore, clock mclock.Clock) *nodeDB {
cache, _ := lru.New(balanceCacheLimit)
ndb := &nodeDB{
db: db,
cache: cache,
auxbuf: make([]byte, 37),
clock: clock,
closeCh: make(chan struct{}),
}
binary.BigEndian.PutUint16(ndb.verbuf[:], uint16(nodeDBVersion))
go ndb.expirer()
return ndb
}
func (db *nodeDB) close() {
close(db.closeCh)
}
func (db *nodeDB) getPrefix(neg bool) []byte {
prefix := positiveBalancePrefix
if neg {
prefix = negativeBalancePrefix
}
return append(db.verbuf[:], prefix...)
}
func (db *nodeDB) key(id []byte, neg bool) []byte {
prefix := positiveBalancePrefix
if neg {
prefix = negativeBalancePrefix
}
if len(prefix)+len(db.verbuf)+len(id) > len(db.auxbuf) {
db.auxbuf = append(db.auxbuf, make([]byte, len(prefix)+len(db.verbuf)+len(id)-len(db.auxbuf))...)
}
copy(db.auxbuf[:len(db.verbuf)], db.verbuf[:])
copy(db.auxbuf[len(db.verbuf):len(db.verbuf)+len(prefix)], prefix)
copy(db.auxbuf[len(prefix)+len(db.verbuf):len(prefix)+len(db.verbuf)+len(id)], id)
return db.auxbuf[:len(prefix)+len(db.verbuf)+len(id)]
}
func (db *nodeDB) getExpiration() (utils.Fixed64, utils.Fixed64) {
blob, err := db.db.Get(append(db.verbuf[:], expirationKey...))
if err != nil || len(blob) != 16 {
return 0, 0
}
return utils.Fixed64(binary.BigEndian.Uint64(blob[:8])), utils.Fixed64(binary.BigEndian.Uint64(blob[8:16]))
}
func (db *nodeDB) setExpiration(pos, neg utils.Fixed64) {
var buff [16]byte
binary.BigEndian.PutUint64(buff[:8], uint64(pos))
binary.BigEndian.PutUint64(buff[8:16], uint64(neg))
db.db.Put(append(db.verbuf[:], expirationKey...), buff[:16])
}
func (db *nodeDB) getOrNewBalance(id []byte, neg bool) utils.ExpiredValue {
key := db.key(id, neg)
item, exist := db.cache.Get(string(key))
if exist {
return item.(utils.ExpiredValue)
}
var b utils.ExpiredValue
enc, err := db.db.Get(key)
if err != nil || len(enc) == 0 {
return b
}
if err := rlp.DecodeBytes(enc, &b); err != nil {
log.Crit("Failed to decode positive balance", "err", err)
}
db.cache.Add(string(key), b)
return b
}
func (db *nodeDB) setBalance(id []byte, neg bool, b utils.ExpiredValue) {
key := db.key(id, neg)
enc, err := rlp.EncodeToBytes(&(b))
if err != nil {
log.Crit("Failed to encode positive balance", "err", err)
}
db.db.Put(key, enc)
db.cache.Add(string(key), b)
}
func (db *nodeDB) delBalance(id []byte, neg bool) {
key := db.key(id, neg)
db.db.Delete(key)
db.cache.Remove(string(key))
}
// getPosBalanceIDs returns a lexicographically ordered list of IDs of accounts
// with a positive balance
func (db *nodeDB) getPosBalanceIDs(start, stop enode.ID, maxCount int) (result []enode.ID) {
if maxCount <= 0 {
return
}
prefix := db.getPrefix(false)
keylen := len(prefix) + len(enode.ID{})
it := db.db.NewIterator(prefix, start.Bytes())
defer it.Release()
for it.Next() {
var id enode.ID
if len(it.Key()) != keylen {
return
}
copy(id[:], it.Key()[keylen-len(id):])
if bytes.Compare(id.Bytes(), stop.Bytes()) >= 0 {
return
}
result = append(result, id)
if len(result) == maxCount {
return
}
}
return
}
// forEachBalance iterates all balances and passes values to callback.
func (db *nodeDB) forEachBalance(neg bool, callback func(id enode.ID, balance utils.ExpiredValue) bool) {
prefix := db.getPrefix(neg)
keylen := len(prefix) + len(enode.ID{})
it := db.db.NewIterator(prefix, nil)
defer it.Release()
for it.Next() {
var id enode.ID
if len(it.Key()) != keylen {
return
}
copy(id[:], it.Key()[keylen-len(id):])
var b utils.ExpiredValue
if err := rlp.DecodeBytes(it.Value(), &b); err != nil {
continue
}
if !callback(id, b) {
return
}
}
}
func (db *nodeDB) expirer() {
for {
select {
case <-db.clock.After(dbCleanupCycle):
db.expireNodes()
case <-db.closeCh:
return
}
}
}
// expireNodes iterates the whole node db and checks whether the
// token balances can be deleted.
func (db *nodeDB) expireNodes() {
var (
visited int
deleted int
start = time.Now()
)
for _, neg := range []bool{false, true} {
iter := db.db.NewIterator(db.getPrefix(neg), nil)
for iter.Next() {
visited++
var balance utils.ExpiredValue
if err := rlp.DecodeBytes(iter.Value(), &balance); err != nil {
log.Crit("Failed to decode negative balance", "err", err)
}
if db.evictCallBack != nil && db.evictCallBack(db.clock.Now(), neg, balance) {
deleted++
db.db.Delete(iter.Key())
}
}
}
// Invoke testing hook if it's not nil.
if db.cleanupHook != nil {
db.cleanupHook()
}
log.Debug("Expire nodes", "visited", visited, "deleted", deleted, "elapsed", common.PrettyDuration(time.Since(start)))
}