1 files changed, 25 insertions, 23 deletions

diff --git a/les/peer.go b/les/peer.go
index bcd91cd83..edf3c7c85 100644
--- a/les/peer.go
+++ b/les/peer.go
@@ -111,7 +111,7 @@ type peer struct {
 	fcServer       *flowcontrol.ServerNode // nil if the peer is client only
 	fcParams       flowcontrol.ServerParams
 	fcCosts        requestCostTable
-	balanceTracker *balanceTracker // set by clientPool.connect, used and removed by ProtocolManager.handle
+	balanceTracker *balanceTracker // set by clientPool.connect, used and removed by serverHandler.
 
 	trusted                 bool
 	onlyAnnounce            bool
@@ -291,6 +291,11 @@ func (p *peer) updateCapacity(cap uint64) {
 	p.queueSend(func() { p.SendAnnounce(announceData{Update: kvList}) })
 }
 
+func (p *peer) responseID() uint64 {
+	p.responseCount += 1
+	return p.responseCount
+}
+
 func sendRequest(w p2p.MsgWriter, msgcode, reqID, cost uint64, data interface{}) error {
 	type req struct {
 		ReqID uint64
@@ -373,6 +378,7 @@ func (p *peer) HasBlock(hash common.Hash, number uint64, hasState bool) bool {
 	}
 	hasBlock := p.hasBlock
 	p.lock.RUnlock()
+
 	return head >= number && number >= since && (recent == 0 || number+recent+4 > head) && hasBlock != nil && hasBlock(hash, number, hasState)
 }
 
@@ -571,6 +577,8 @@ func (p *peer) Handshake(td *big.Int, head common.Hash, headNum uint64, genesis
 	defer p.lock.Unlock()
 
 	var send keyValueList
+
+	// Add some basic handshake fields
 	send = send.add("protocolVersion", uint64(p.version))
 	send = send.add("networkId", p.network)
 	send = send.add("headTd", td)
@@ -578,7 +586,8 @@ func (p *peer) Handshake(td *big.Int, head common.Hash, headNum uint64, genesis
 	send = send.add("headNum", headNum)
 	send = send.add("genesisHash", genesis)
 	if server != nil {
-		if !server.onlyAnnounce {
+		// Add some information which services server can offer.
+		if !server.config.UltraLightOnlyAnnounce {
 			send = send.add("serveHeaders", nil)
 			send = send.add("serveChainSince", uint64(0))
 			send = send.add("serveStateSince", uint64(0))
@@ -594,25 +603,28 @@ func (p *peer) Handshake(td *big.Int, head common.Hash, headNum uint64, genesis
 		}
 		send = send.add("flowControl/BL", server.defParams.BufLimit)
 		send = send.add("flowControl/MRR", server.defParams.MinRecharge)
+
 		var costList RequestCostList
-		if server.costTracker != nil {
-			costList = server.costTracker.makeCostList(server.costTracker.globalFactor())
+		if server.costTracker.testCostList != nil {
+			costList = server.costTracker.testCostList
 		} else {
-			costList = testCostList(server.testCost)
+			costList = server.costTracker.makeCostList(server.costTracker.globalFactor())
 		}
 		send = send.add("flowControl/MRC", costList)
 		p.fcCosts = costList.decode(ProtocolLengths[uint(p.version)])
 		p.fcParams = server.defParams
 
-		if server.protocolManager != nil && server.protocolManager.reg != nil && server.protocolManager.reg.isRunning() {
-			cp, height := server.protocolManager.reg.stableCheckpoint()
+		// Add advertised checkpoint and register block height which
+		// client can verify the checkpoint validity.
+		if server.oracle != nil && server.oracle.isRunning() {
+			cp, height := server.oracle.stableCheckpoint()
 			if cp != nil {
 				send = send.add("checkpoint/value", cp)
 				send = send.add("checkpoint/registerHeight", height)
 			}
 		}
 	} else {
-		//on client node
+		// Add some client-specific handshake fields
 		p.announceType = announceTypeSimple
 		if p.trusted {
 			p.announceType = announceTypeSigned
@@ -663,17 +675,12 @@ func (p *peer) Handshake(td *big.Int, head common.Hash, headNum uint64, genesis
 	}
 
 	if server != nil {
-		// until we have a proper peer connectivity API, allow LES connection to other servers
-		/*if recv.get("serveStateSince", nil) == nil {
-			return errResp(ErrUselessPeer, "wanted client, got server")
-		}*/
 		if recv.get("announceType", &p.announceType) != nil {
-			//set default announceType on server side
+			// set default announceType on server side
 			p.announceType = announceTypeSimple
 		}
 		p.fcClient = flowcontrol.NewClientNode(server.fcManager, server.defParams)
 	} else {
-		//mark OnlyAnnounce server if "serveHeaders", "serveChainSince", "serveStateSince" or "txRelay" fields don't exist
 		if recv.get("serveChainSince", &p.chainSince) != nil {
 			p.onlyAnnounce = true
 		}
@@ -730,15 +737,10 @@ func (p *peer) updateFlowControl(update keyValueMap) {
 	if p.fcServer == nil {
 		return
 	}
-	params := p.fcParams
-	updateParams := false
-	if update.get("flowControl/BL", &params.BufLimit) == nil {
-		updateParams = true
-	}
-	if update.get("flowControl/MRR", &params.MinRecharge) == nil {
-		updateParams = true
-	}
-	if updateParams {
+	// If any of the flow control params is nil, refuse to update.
+	var params flowcontrol.ServerParams
+	if update.get("flowControl/BL", &params.BufLimit) == nil && update.get("flowControl/MRR", &params.MinRecharge) == nil {
+		// todo can light client set a minimal acceptable flow control params?
 		p.fcParams = params
 		p.fcServer.UpdateParams(params)
 	}