les: switch to new discv5 (#21940)

This PR enables running the new discv5 protocol in both LES client
and server mode. In client mode it mixes discv5 and dnsdisc iterators
(if both are enabled) and filters incoming ENRs for "les" tag and fork ID.
The old p2p/discv5 package and all references to it are removed.

Co-authored-by: Felix Lange <fjl@twurst.com>

les/server.go

@@ -29,7 +29,6 @@ import (
 	"github.com/ethereum/go-ethereum/log"
 	"github.com/ethereum/go-ethereum/node"
 	"github.com/ethereum/go-ethereum/p2p"
-	"github.com/ethereum/go-ethereum/p2p/discv5"
 	"github.com/ethereum/go-ethereum/p2p/enode"
 	"github.com/ethereum/go-ethereum/p2p/enr"
 	"github.com/ethereum/go-ethereum/p2p/nodestate"
@@ -58,7 +57,6 @@ type LesServer struct {
 	archiveMode bool // Flag whether the ethereum node runs in archive mode.
 	handler     *serverHandler
 	broadcaster *broadcaster
-	lesTopics   []discv5.Topic
 	privateKey  *ecdsa.PrivateKey
 
 	// Flow control and capacity management
@@ -77,11 +75,6 @@ type LesServer struct {
 
 func NewLesServer(node *node.Node, e *eth.Ethereum, config *eth.Config) (*LesServer, error) {
 	ns := nodestate.NewNodeStateMachine(nil, nil, mclock.System{}, serverSetup)
-	// Collect les protocol version information supported by local node.
-	lesTopics := make([]discv5.Topic, len(AdvertiseProtocolVersions))
-	for i, pv := range AdvertiseProtocolVersions {
-		lesTopics[i] = lesTopic(e.BlockChain().Genesis().Hash(), pv)
-	}
 	// Calculate the number of threads used to service the light client
 	// requests based on the user-specified value.
 	threads := config.LightServ * 4 / 100
@@ -103,7 +96,6 @@ func NewLesServer(node *node.Node, e *eth.Ethereum, config *eth.Config) (*LesSer
 		ns:           ns,
 		archiveMode:  e.ArchiveMode(),
 		broadcaster:  newBroadcaster(ns),
-		lesTopics:    lesTopics,
 		fcManager:    flowcontrol.NewClientManager(nil, &mclock.System{}),
 		servingQueue: newServingQueue(int64(time.Millisecond*10), float64(config.LightServ)/100),
 		threadsBusy:  config.LightServ/100 + 1,
@@ -203,19 +195,6 @@ func (s *LesServer) Start() error {
 	s.wg.Add(1)
 	go s.capacityManagement()
 
-	if s.p2pSrv.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")
-
-				s.p2pSrv.DiscV5.RegisterTopic(topic, s.closeCh)
-			}()
-		}
-	}
-
 	return nil
 }