X-Git-Url: http://git.osdn.net/view?p=bytom%2Fvapor.git;a=blobdiff_plain;f=netsync%2Fconsensusmgr%2Fblock_fetcher.go;h=6e28330e37b7c1af92361a2c31bbd3ca250f8af0;hp=3c92b38b545f86783a2ca96c6567af15f8152686;hb=1337be95f74a1d2a1a7316737efde413f29bcb2f;hpb=54373c1a3efe0e373ec1605840a4363e4b246c46

diff --git a/netsync/consensusmgr/block_fetcher.go b/netsync/consensusmgr/block_fetcher.go
index 3c92b38b..6e28330e 100644
--- a/netsync/consensusmgr/block_fetcher.go
+++ b/netsync/consensusmgr/block_fetcher.go
@@ -1,45 +1,44 @@
 package consensusmgr
 
 import (
-	"github.com/sirupsen/logrus"
+	log "github.com/sirupsen/logrus"
 	"gopkg.in/karalabe/cookiejar.v2/collections/prque"
 
-	"github.com/vapor/netsync/peers"
-	"github.com/vapor/p2p/security"
-	"github.com/vapor/protocol/bc"
+	"github.com/bytom/vapor/p2p/security"
+	"github.com/bytom/vapor/protocol/bc"
 )
 
 const (
 	maxBlockDistance = 64
-	maxMsgSetSize    = 128
 	newBlockChSize   = 64
+	msgLimit         = 128 // peer message number limit
 )
 
 // blockFetcher is responsible for accumulating block announcements from various peers
 // and scheduling them for retrieval.
 type blockFetcher struct {
 	chain Chain
-	peers *peers.PeerSet
+	peers Peers
 
 	newBlockCh chan *blockMsg
-	queue      *prque.Prque
-	msgSet     map[bc.Hash]*blockMsg
+	queue      *prque.Prque          // block import priority queue
+	msgSet     map[bc.Hash]*blockMsg // already queued blocks
+	msgCounter map[string]int        // per peer msg counter to prevent DOS
 }
 
 //NewBlockFetcher creates a block fetcher to retrieve blocks of the new propose.
-func newBlockFetcher(chain Chain, peers *peers.PeerSet) *blockFetcher {
-	f := &blockFetcher{
+func newBlockFetcher(chain Chain, peers Peers) *blockFetcher {
+	return &blockFetcher{
 		chain:      chain,
 		peers:      peers,
 		newBlockCh: make(chan *blockMsg, newBlockChSize),
 		queue:      prque.New(),
 		msgSet:     make(map[bc.Hash]*blockMsg),
+		msgCounter: make(map[string]int),
 	}
-	go f.blockProcessor()
-	return f
 }
 
-func (f *blockFetcher) blockProcessor() {
+func (f *blockFetcher) blockProcessorLoop() {
 	for {
 		for !f.queue.Empty() {
 			msg := f.queue.PopItem().(*blockMsg)
@@ -50,14 +49,25 @@ func (f *blockFetcher) blockProcessor() {
 
 			f.insert(msg)
 			delete(f.msgSet, msg.block.Hash())
+			f.msgCounter[msg.peerID]--
+			if f.msgCounter[msg.peerID] <= 0 {
+				delete(f.msgCounter, msg.peerID)
+			}
 		}
-		f.add(<-f.newBlockCh)
+		f.add(<-f.newBlockCh, msgLimit)
 	}
 }
 
-func (f *blockFetcher) add(msg *blockMsg) {
+func (f *blockFetcher) add(msg *blockMsg, limit int) {
+	// prevent DOS
+	count := f.msgCounter[msg.peerID] + 1
+	if count > limit {
+		log.WithFields(log.Fields{"module": logModule, "peer": msg.peerID, "limit": limit}).Warn("The number of peer messages exceeds the limit")
+		return
+	}
+
 	bestHeight := f.chain.BestBlockHeight()
-	if len(f.msgSet) > maxMsgSetSize || bestHeight > msg.block.Height || msg.block.Height-bestHeight > maxBlockDistance {
+	if bestHeight > msg.block.Height || msg.block.Height-bestHeight > maxBlockDistance {
 		return
 	}
 
@@ -65,7 +75,8 @@ func (f *blockFetcher) add(msg *blockMsg) {
 	if _, ok := f.msgSet[blockHash]; !ok {
 		f.msgSet[blockHash] = msg
 		f.queue.Push(msg, -float32(msg.block.Height))
-		logrus.WithFields(logrus.Fields{
+		f.msgCounter[msg.peerID] = count
+		log.WithFields(log.Fields{
 			"module":       logModule,
 			"block height": msg.block.Height,
 			"block hash":   blockHash.String(),
@@ -80,7 +91,6 @@ func (f *blockFetcher) insert(msg *blockMsg) {
 		if peer == nil {
 			return
 		}
-
 		f.peers.ProcessIllegal(msg.peerID, security.LevelMsgIllegal, err.Error())
 		return
 	}
@@ -91,12 +101,12 @@ func (f *blockFetcher) insert(msg *blockMsg) {
 
 	proposeMsg, err := NewBlockProposeMsg(msg.block)
 	if err != nil {
-		logrus.WithFields(logrus.Fields{"module": logModule, "err": err}).Error("failed on create BlockProposeMsg")
+		log.WithFields(log.Fields{"module": logModule, "err": err}).Error("failed on create BlockProposeMsg")
 		return
 	}
 
 	if err := f.peers.BroadcastMsg(NewBroadcastMsg(proposeMsg, consensusChannel)); err != nil {
-		logrus.WithFields(logrus.Fields{"module": logModule, "err": err}).Error("failed on broadcast proposed block")
+		log.WithFields(log.Fields{"module": logModule, "err": err}).Error("failed on broadcast proposed block")
 		return
 	}
 }