les: fix crasher in NodeInfo when running as server (#17419)

* les: fix crasher in NodeInfo when running as server

The ProtocolManager computes CHT and Bloom trie roots by asking the
indexers for their current head. It tried to get the indexers from
LesOdr, but no LesOdr instance is created in server mode.

Attempt to fix this by moving the indexers, protocol creation and
NodeInfo to a new lesCommons struct which is embedded into both server
and client.

All this setup code should really be cleaned up, but this is just a
hotfix so we have to do that some other time.

* les: fix commons protocol maker

1 files changed, 27 insertions, 101 deletions

diff --git a/les/handler.go b/les/handler.go
index ccb4a8844..ca40eaabf 100644
--- a/les/handler.go
+++ b/les/handler.go
@@ -20,7 +20,6 @@ package les
 import (
 	"encoding/binary"
 	"encoding/json"
-	"errors"
 	"fmt"
 	"math/big"
 	"net"
@@ -40,7 +39,6 @@ import (
 	"github.com/ethereum/go-ethereum/light"
 	"github.com/ethereum/go-ethereum/log"
 	"github.com/ethereum/go-ethereum/p2p"
-	"github.com/ethereum/go-ethereum/p2p/discover"
 	"github.com/ethereum/go-ethereum/p2p/discv5"
 	"github.com/ethereum/go-ethereum/params"
 	"github.com/ethereum/go-ethereum/rlp"
@@ -65,10 +63,6 @@ const (
 	disableClientRemovePeer = false
 )
 
-// errIncompatibleConfig is returned if the requested protocols and configs are
-// not compatible (low protocol version restrictions and high requirements).
-var errIncompatibleConfig = errors.New("incompatible configuration")
-
 func errResp(code errCode, format string, v ...interface{}) error {
 	return fmt.Errorf("%v - %v", code, fmt.Sprintf(format, v...))
 }
@@ -115,8 +109,6 @@ type ProtocolManager struct {
 	peers      *peerSet
 	maxPeers   int
 
-	SubProtocols []p2p.Protocol
-
 	eventMux *event.TypeMux
 
 	// channels for fetcher, syncer, txsyncLoop
@@ -131,7 +123,7 @@ type ProtocolManager struct {
 
 // NewProtocolManager returns a new ethereum sub protocol manager. The Ethereum sub protocol manages peers capable
 // with the ethereum network.
-func NewProtocolManager(chainConfig *params.ChainConfig, lightSync bool, protocolVersions []uint, networkId uint64, mux *event.TypeMux, engine consensus.Engine, peers *peerSet, blockchain BlockChain, txpool txPool, chainDb ethdb.Database, odr *LesOdr, txrelay *LesTxRelay, serverPool *serverPool, quitSync chan struct{}, wg *sync.WaitGroup) (*ProtocolManager, error) {
+func NewProtocolManager(chainConfig *params.ChainConfig, lightSync bool, networkId uint64, mux *event.TypeMux, engine consensus.Engine, peers *peerSet, blockchain BlockChain, txpool txPool, chainDb ethdb.Database, odr *LesOdr, txrelay *LesTxRelay, serverPool *serverPool, quitSync chan struct{}, wg *sync.WaitGroup) (*ProtocolManager, error) {
 	// Create the protocol manager with the base fields
 	manager := &ProtocolManager{
 		lightSync:   lightSync,
@@ -155,54 +147,6 @@ func NewProtocolManager(chainConfig *params.ChainConfig, lightSync bool, protoco
 		manager.reqDist = odr.retriever.dist
 	}
 
-	// Initiate a sub-protocol for every implemented version we can handle
-	manager.SubProtocols = make([]p2p.Protocol, 0, len(protocolVersions))
-	for _, version := range protocolVersions {
-		// Compatible, initialize the sub-protocol
-		version := version // Closure for the run
-		manager.SubProtocols = append(manager.SubProtocols, p2p.Protocol{
-			Name:    "les",
-			Version: version,
-			Length:  ProtocolLengths[version],
-			Run: func(p *p2p.Peer, rw p2p.MsgReadWriter) error {
-				var entry *poolEntry
-				peer := manager.newPeer(int(version), networkId, p, rw)
-				if manager.serverPool != nil {
-					addr := p.RemoteAddr().(*net.TCPAddr)
-					entry = manager.serverPool.connect(peer, addr.IP, uint16(addr.Port))
-				}
-				peer.poolEntry = entry
-				select {
-				case manager.newPeerCh <- peer:
-					manager.wg.Add(1)
-					defer manager.wg.Done()
-					err := manager.handle(peer)
-					if entry != nil {
-						manager.serverPool.disconnect(entry)
-					}
-					return err
-				case <-manager.quitSync:
-					if entry != nil {
-						manager.serverPool.disconnect(entry)
-					}
-					return p2p.DiscQuitting
-				}
-			},
-			NodeInfo: func() interface{} {
-				return manager.NodeInfo()
-			},
-			PeerInfo: func(id discover.NodeID) interface{} {
-				if p := manager.peers.Peer(fmt.Sprintf("%x", id[:8])); p != nil {
-					return p.Info()
-				}
-				return nil
-			},
-		})
-	}
-	if len(manager.SubProtocols) == 0 {
-		return nil, errIncompatibleConfig
-	}
-
 	removePeer := manager.removePeer
 	if disableClientRemovePeer {
 		removePeer = func(id string) {}
@@ -262,6 +206,32 @@ func (pm *ProtocolManager) Stop() {
 	log.Info("Light Ethereum protocol stopped")
 }
 
+// runPeer is the p2p protocol run function for the given version.
+func (pm *ProtocolManager) runPeer(version uint, p *p2p.Peer, rw p2p.MsgReadWriter) error {
+	var entry *poolEntry
+	peer := pm.newPeer(int(version), pm.networkId, p, rw)
+	if pm.serverPool != nil {
+		addr := p.RemoteAddr().(*net.TCPAddr)
+		entry = pm.serverPool.connect(peer, addr.IP, uint16(addr.Port))
+	}
+	peer.poolEntry = entry
+	select {
+	case pm.newPeerCh <- peer:
+		pm.wg.Add(1)
+		defer pm.wg.Done()
+		err := pm.handle(peer)
+		if entry != nil {
+			pm.serverPool.disconnect(entry)
+		}
+		return err
+	case <-pm.quitSync:
+		if entry != nil {
+			pm.serverPool.disconnect(entry)
+		}
+		return p2p.DiscQuitting
+	}
+}
+
 func (pm *ProtocolManager) newPeer(pv int, nv uint64, p *p2p.Peer, rw p2p.MsgReadWriter) *peer {
 	return newPeer(pv, nv, p, newMeteredMsgWriter(rw))
 }
@@ -1203,50 +1173,6 @@ func (pm *ProtocolManager) txStatus(hashes []common.Hash) []txStatus {
 	return stats
 }
 
-// NodeInfo represents a short summary of the Ethereum sub-protocol metadata
-// known about the host peer.
-type NodeInfo struct {
-	Network    uint64                  `json:"network"`    // Ethereum network ID (1=Frontier, 2=Morden, Ropsten=3, Rinkeby=4)
-	Difficulty *big.Int                `json:"difficulty"` // Total difficulty of the host's blockchain
-	Genesis    common.Hash             `json:"genesis"`    // SHA3 hash of the host's genesis block
-	Config     *params.ChainConfig     `json:"config"`     // Chain configuration for the fork rules
-	Head       common.Hash             `json:"head"`       // SHA3 hash of the host's best owned block
-	CHT        light.TrustedCheckpoint `json:"cht"`        // Trused CHT checkpoint for fast catchup
-}
-
-// NodeInfo retrieves some protocol metadata about the running host node.
-func (self *ProtocolManager) NodeInfo() *NodeInfo {
-	head := self.blockchain.CurrentHeader()
-	hash := head.Hash()
-
-	var cht light.TrustedCheckpoint
-
-	sections, _, sectionHead := self.odr.ChtIndexer().Sections()
-	sections2, _, sectionHead2 := self.odr.BloomTrieIndexer().Sections()
-	if sections2 < sections {
-		sections = sections2
-		sectionHead = sectionHead2
-	}
-	if sections > 0 {
-		sectionIndex := sections - 1
-		cht = light.TrustedCheckpoint{
-			SectionIdx:  sectionIndex,
-			SectionHead: sectionHead,
-			CHTRoot:     light.GetChtRoot(self.chainDb, sectionIndex, sectionHead),
-			BloomRoot:   light.GetBloomTrieRoot(self.chainDb, sectionIndex, sectionHead),
-		}
-	}
-
-	return &NodeInfo{
-		Network:    self.networkId,
-		Difficulty: self.blockchain.GetTd(hash, head.Number.Uint64()),
-		Genesis:    self.blockchain.Genesis().Hash(),
-		Config:     self.blockchain.Config(),
-		Head:       hash,
-		CHT:        cht,
-	}
-}
-
 // downloaderPeerNotify implements peerSetNotify
 type downloaderPeerNotify ProtocolManager