les: split handshake

les, core: introduce forkid for les4

les: update peer unit test

les: check peer version in handler

les: fix linter

les: address comments

Author: rjl493456442

core/forkid/forkid.go

@@ -27,7 +27,7 @@ import (
 	"strings"
 
 	"github.com/ethereum/go-ethereum/common"
-	"github.com/ethereum/go-ethereum/core"
+	"github.com/ethereum/go-ethereum/core/types"
 	"github.com/ethereum/go-ethereum/log"
 	"github.com/ethereum/go-ethereum/params"
 )
@@ -44,6 +44,18 @@ var (
 	ErrLocalIncompatibleOrStale = errors.New("local incompatible or needs update")
 )
 
+// Blockchain defines all necessary method to build a forkID.
+type Blockchain interface {
+	// Config retrieves the chain's fork configuration.
+	Config() *params.ChainConfig
+
+	// Genesis retrieves the chain's genesis block.
+	Genesis() *types.Block
+
+	// CurrentHeader retrieves the current head header of the canonical chain.
+	CurrentHeader() *types.Header
+}
+
 // ID is a fork identifier as defined by EIP-2124.
 type ID struct {
 	Hash [4]byte // CRC32 checksum of the genesis block and passed fork block numbers
@@ -54,7 +66,7 @@ type ID struct {
 type Filter func(id ID) error
 
 // NewID calculates the Ethereum fork ID from the chain config and head.
-func NewID(chain *core.BlockChain) ID {
+func NewID(chain Blockchain) ID {
 	return newID(
 		chain.Config(),
 		chain.Genesis().Hash(),
@@ -85,7 +97,7 @@ func newID(config *params.ChainConfig, genesis common.Hash, head uint64) ID {
 
 // NewFilter creates a filter that returns if a fork ID should be rejected or not
 // based on the local chain's status.
-func NewFilter(chain *core.BlockChain) Filter {
+func NewFilter(chain Blockchain) Filter {
 	return newFilter(
 		chain.Config(),
 		chain.Genesis().Hash(),

les/client_handler.go

@@ -23,6 +23,7 @@ import (
 
 	"github.com/ethereum/go-ethereum/common"
 	"github.com/ethereum/go-ethereum/common/mclock"
+	"github.com/ethereum/go-ethereum/core/forkid"
 	"github.com/ethereum/go-ethereum/core/types"
 	"github.com/ethereum/go-ethereum/eth/downloader"
 	"github.com/ethereum/go-ethereum/light"
@@ -35,6 +36,7 @@ import (
 // responses.
 type clientHandler struct {
 	ulc        *ulc
+	forkFilter forkid.Filter
 	checkpoint *params.TrustedCheckpoint
 	fetcher    *lightFetcher
 	downloader *downloader.Downloader
@@ -47,6 +49,7 @@ type clientHandler struct {
 
 func newClientHandler(ulcServers []string, ulcFraction int, checkpoint *params.TrustedCheckpoint, backend *LightEthereum) *clientHandler {
 	handler := &clientHandler{
+		forkFilter: forkid.NewFilter(backend.blockchain),
 		checkpoint: checkpoint,
 		backend:    backend,
 		closeCh:    make(chan struct{}),
@@ -107,7 +110,7 @@ func (h *clientHandler) handle(p *peer) error {
 		number = head.Number.Uint64()
 		td     = h.backend.blockchain.GetTd(hash, number)
 	)
-	if err := p.Handshake(td, hash, number, h.backend.blockchain.Genesis().Hash(), nil); err != nil {
+	if err := p.handshakeWithServer(td, hash, number, h.backend.blockchain.Genesis().Hash(), forkid.NewID(h.backend.blockchain), h.forkFilter); err != nil {
 		p.Log().Debug("Light Ethereum handshake failed", "err", err)
 		return err
 	}
@@ -159,8 +162,8 @@ func (h *clientHandler) handleMsg(p *peer) error {
 	var deliverMsg *Msg
 
 	// Handle the message depending on its contents
-	switch msg.Code {
-	case AnnounceMsg:
+	switch {
+	case msg.Code == AnnounceMsg:
 		p.Log().Trace("Received announce message")
 		var req announceData
 		if err := msg.Decode(&req); err != nil {
@@ -189,7 +192,7 @@ func (h *clientHandler) handleMsg(p *peer) error {
 			p.Log().Trace("Announce message content", "number", req.Number, "hash", req.Hash, "td", req.Td, "reorg", req.ReorgDepth)
 			h.fetcher.announce(p, &req)
 		}
-	case BlockHeadersMsg:
+	case msg.Code == BlockHeadersMsg:
 		p.Log().Trace("Received block header response message")
 		var resp struct {
 			ReqID, BV uint64
@@ -206,7 +209,7 @@ func (h *clientHandler) handleMsg(p *peer) error {
 				log.Debug("Failed to deliver headers", "err", err)
 			}
 		}
-	case BlockBodiesMsg:
+	case msg.Code == BlockBodiesMsg:
 		p.Log().Trace("Received block bodies response")
 		var resp struct {
 			ReqID, BV uint64
@@ -221,7 +224,7 @@ func (h *clientHandler) handleMsg(p *peer) error {
 			ReqID:   resp.ReqID,
 			Obj:     resp.Data,
 		}
-	case CodeMsg:
+	case msg.Code == CodeMsg:
 		p.Log().Trace("Received code response")
 		var resp struct {
 			ReqID, BV uint64
@@ -236,7 +239,7 @@ func (h *clientHandler) handleMsg(p *peer) error {
 			ReqID:   resp.ReqID,
 			Obj:     resp.Data,
 		}
-	case ReceiptsMsg:
+	case msg.Code == ReceiptsMsg:
 		p.Log().Trace("Received receipts response")
 		var resp struct {
 			ReqID, BV uint64
@@ -251,7 +254,7 @@ func (h *clientHandler) handleMsg(p *peer) error {
 			ReqID:   resp.ReqID,
 			Obj:     resp.Receipts,
 		}
-	case ProofsV2Msg:
+	case msg.Code == ProofsV2Msg:
 		p.Log().Trace("Received les/2 proofs response")
 		var resp struct {
 			ReqID, BV uint64
@@ -266,7 +269,7 @@ func (h *clientHandler) handleMsg(p *peer) error {
 			ReqID:   resp.ReqID,
 			Obj:     resp.Data,
 		}
-	case HelperTrieProofsMsg:
+	case msg.Code == HelperTrieProofsMsg:
 		p.Log().Trace("Received helper trie proof response")
 		var resp struct {
 			ReqID, BV uint64
@@ -281,7 +284,7 @@ func (h *clientHandler) handleMsg(p *peer) error {
 			ReqID:   resp.ReqID,
 			Obj:     resp.Data,
 		}
-	case TxStatusMsg:
+	case msg.Code == TxStatusMsg:
 		p.Log().Trace("Received tx status response")
 		var resp struct {
 			ReqID, BV uint64
@@ -296,11 +299,11 @@ func (h *clientHandler) handleMsg(p *peer) error {
 			ReqID:   resp.ReqID,
 			Obj:     resp.Status,
 		}
-	case StopMsg:
+	case msg.Code == StopMsg && p.version >= lpv3:
 		p.freezeServer(true)
 		h.backend.retriever.frozen(p)
 		p.Log().Debug("Service stopped")
-	case ResumeMsg:
+	case msg.Code == ResumeMsg && p.version >= lpv3:
 		var bv uint64
 		if err := msg.Decode(&bv); err != nil {
 			return errResp(ErrDecode, "msg %v: %v", msg, err)