les: add protocol version 3 for Stop/Resume messages

les/peer.go

@@ -144,6 +144,13 @@ func (p *peer) rejectUpdate(size uint64) bool {
 // region. The client is also notified about being frozen/unfrozen with a Stop/Resume
 // message.
 func (p *peer) freezeClient() {
+	if p.version < lpv3 {
+		// if Stop/Resume is not supported then just drop the peer after setting
+		// its frozen status permanently
+		atomic.StoreUint32(&p.frozen, 1)
+		p.Peer.Disconnect(p2p.DiscUselessPeer)
+		return
+	}
 	if atomic.SwapUint32(&p.frozen, 1) == 0 {
 		go func() {
 			p.SendStop()

les/protocol.go

@@ -32,17 +32,18 @@ import (
 // Constants to match up protocol versions and messages
 const (
 	lpv2 = 2
+	lpv3 = 3
 )
 
 // Supported versions of the les protocol (first is primary)
 var (
-	ClientProtocolVersions    = []uint{lpv2}
-	ServerProtocolVersions    = []uint{lpv2}
+	ClientProtocolVersions    = []uint{lpv2, lpv3}
+	ServerProtocolVersions    = []uint{lpv2, lpv3}
 	AdvertiseProtocolVersions = []uint{lpv2} // clients are searching for the first advertised protocol in the list
 )
 
 // Number of implemented message corresponding to different protocol versions.
-var ProtocolLengths = map[uint]uint64{lpv2: 24}
+var ProtocolLengths = map[uint]uint64{lpv2: 22, lpv3: 24}
 
 const (
 	NetworkId          = 1
@@ -70,8 +71,9 @@ const (
 	SendTxV2Msg            = 0x13
 	GetTxStatusMsg         = 0x14
 	TxStatusMsg            = 0x15
-	StopMsg                = 0x16
-	ResumeMsg              = 0x17
+	// Protocol messages introduced in LPV3
+	StopMsg   = 0x16
+	ResumeMsg = 0x17
 )
 
 type requestInfo struct {