beacon/light: various small changes

beacon/light/api/light_api.go

@@ -131,15 +131,15 @@ func (api *BeaconLightApi) GetBestUpdatesAndCommittees(firstPeriod, count uint64
 //
 // See data structure definition here:
 // https://github.com/ethereum/consensus-specs/blob/dev/specs/altair/light-client/sync-protocol.md#lightclientoptimisticupdate
-func (api *BeaconLightApi) GetOptimisticHeadUpdate() (types.SignedHead, error) {
+func (api *BeaconLightApi) GetOptimisticHeadUpdate() (types.SignedHeader, error) {
 	resp, err := api.httpGet("/eth/v1/beacon/light_client/optimistic_update")
 	if err != nil {
-		return types.SignedHead{}, err
+		return types.SignedHeader{}, err
 	}
 	return decodeOptimisticHeadUpdate(resp)
 }
 
-func decodeOptimisticHeadUpdate(enc []byte) (types.SignedHead, error) {
+func decodeOptimisticHeadUpdate(enc []byte) (types.SignedHeader, error) {
 	var data struct {
 		Data struct {
 			Header        types.JsonBeaconHeader `json:"attested_header"`
@@ -148,22 +148,22 @@ func decodeOptimisticHeadUpdate(enc []byte) (types.SignedHead, error) {
 		} `json:"data"`
 	}
 	if err := json.Unmarshal(enc, &data); err != nil {
-		return types.SignedHead{}, err
+		return types.SignedHeader{}, err
 	}
 	if data.Data.Header.Beacon.StateRoot == (common.Hash{}) {
 		// workaround for different event encoding format in Lodestar
 		if err := json.Unmarshal(enc, &data.Data); err != nil {
-			return types.SignedHead{}, err
+			return types.SignedHeader{}, err
 		}
 	}
 
 	if len(data.Data.Aggregate.BitMask) != params.SyncCommitteeBitmaskSize {
-		return types.SignedHead{}, errors.New("invalid sync_committee_bits length")
+		return types.SignedHeader{}, errors.New("invalid sync_committee_bits length")
 	}
 	if len(data.Data.Aggregate.Signature) != params.BlsSignatureSize {
-		return types.SignedHead{}, errors.New("invalid sync_committee_signature length")
+		return types.SignedHeader{}, errors.New("invalid sync_committee_signature length")
 	}
-	return types.SignedHead{
+	return types.SignedHeader{
 		Header:        data.Data.Header.Beacon,
 		SyncAggregate: data.Data.Aggregate,
 		SignatureSlot: uint64(data.Data.SignatureSlot),
@@ -309,7 +309,7 @@ func decodeHeadEvent(enc []byte) (uint64, common.Hash, error) {
 // head updates and calls the specified callback functions when they are received.
 // The callbacks are also called for the current head and optimistic head at startup.
 // They are never called concurrently.
-func (api *BeaconLightApi) StartHeadListener(headFn func(slot uint64, blockRoot common.Hash), signedFn func(head types.SignedHead), errFn func(err error)) func() {
+func (api *BeaconLightApi) StartHeadListener(headFn func(slot uint64, blockRoot common.Hash), signedFn func(head types.SignedHeader), errFn func(err error)) func() {
 	closeCh := make(chan struct{})   // initiate closing the stream
 	closedCh := make(chan struct{})  // stream closed (or failed to create)
 	stoppedCh := make(chan struct{}) // sync loop stopped

beacon/light/api/sync_server.go

@@ -39,7 +39,7 @@ func NewSyncServer(api *BeaconLightApi) *SyncServer {
 	return &SyncServer{api: api}
 }
 
-func (s *SyncServer) SubscribeHeads(newHead func(uint64, common.Hash), newSignedHead func(signedHead types.SignedHead)) {
+func (s *SyncServer) SubscribeHeads(newHead func(uint64, common.Hash), newSignedHead func(signedHead types.SignedHeader)) {
 	s.unsubscribe = s.api.StartHeadListener(newHead, newSignedHead, func(err error) {
 		log.Warn("Head event stream error", "err", err)
 	})

beacon/light/committee_chain.go

@@ -421,22 +421,22 @@ func (s *CommitteeChain) getSyncCommittee(period uint64) syncCommittee {
 	return nil
 }
 
-// VerifySignedHead returns true if the given signed head has a valid signature
+// VerifySignedHeader returns true if the given signed head has a valid signature
 // according to the local committee chain. The caller should ensure that the
 // committees advertised by the same source where the signed head came from are
 // synced before verifying the signature.
 // The age of the header is also returned (the time elapsed since the beginning
 // of the given slot, according to the local system clock). If enforceTime is
 // true then negative age (future) headers are rejected.
-func (s *CommitteeChain) VerifySignedHead(head types.SignedHead) (bool, time.Duration) {
+func (s *CommitteeChain) VerifySignedHeader(head types.SignedHeader) (bool, time.Duration) {
 	s.lock.RLock()
 	defer s.lock.RUnlock()
 
-	return s.verifySignedHead(head)
+	return s.verifySignedHeader(head)
 }
 
 // (rlock required)
-func (s *CommitteeChain) verifySignedHead(head types.SignedHead) (bool, time.Duration) {
+func (s *CommitteeChain) verifySignedHeader(head types.SignedHeader) (bool, time.Duration) {
 	var (
 		slotTime = int64(time.Second) * int64(s.genesisData.GenesisTime+head.Header.Slot*12)
 		age      = time.Duration(s.unixNano() - slotTime)
@@ -460,7 +460,7 @@ func (s *CommitteeChain) verifyUpdate(update *types.LightClientUpdate) bool {
 	// verification. Though in reality SignatureSlot is always bigger than update.Header.Slot,
 	// setting them as equal here enforces the rule that they have to be in the same sync
 	// period in order for the light client update proof to be meaningful.
-	ok, age := s.verifySignedHead(types.SignedHead{Header: update.Header, SyncAggregate: update.SyncAggregate, SignatureSlot: update.Header.Slot})
+	ok, age := s.verifySignedHeader(update.SignedHeader)
 	if age < 0 {
 		log.Warn("Future committee update received", "age", age)
 	}

beacon/light/committee_chain_test.go

@@ -287,21 +287,21 @@ func (c *committeeChainTest) insertUpdate(tc *testCommitteeChain, period uint64,
 	}
 }
 
-func (c *committeeChainTest) verifySignedHead(tc *testCommitteeChain, period float64, expOk bool) {
+func (c *committeeChainTest) verifySignedHeader(tc *testCommitteeChain, period float64, expOk bool) {
 	signedHead := tc.makeTestSignedHead(types.Header{Slot: uint64(period * float64(params.SyncPeriodLength))}, 400)
-	if ok, _ := c.chain.VerifySignedHead(signedHead); ok != expOk {
+	if ok, _ := c.chain.VerifySignedHeader(signedHead); ok != expOk {
-		c.t.Errorf("Incorrect output from VerifySignedHead at period %f (expected %v, got %v)", period, expOk, ok)
+		c.t.Errorf("Incorrect output from VerifySignedHeader at period %f (expected %v, got %v)", period, expOk, ok)
 	}
 }
 
 func (c *committeeChainTest) verifyRange(tc *testCommitteeChain, begin, end uint64) {
 	if begin > 0 {
-		c.verifySignedHead(tc, float64(begin)-0.5, false)
+		c.verifySignedHeader(tc, float64(begin)-0.5, false)
 	}
 	for period := begin; period <= end; period++ {
-		c.verifySignedHead(tc, float64(period)+0.5, true)
+		c.verifySignedHeader(tc, float64(period)+0.5, true)
 	}
-	c.verifySignedHead(tc, float64(end)+1.5, false)
+	c.verifySignedHeader(tc, float64(end)+1.5, false)
 }
 
 func newTestGenesis() GenesisData {
@@ -378,9 +378,9 @@ type testCommitteeChain struct {
 	genesisData GenesisData
 }
 
-func (tc *testCommitteeChain) makeTestSignedHead(header types.Header, signerCount int) types.SignedHead {
+func (tc *testCommitteeChain) makeTestSignedHead(header types.Header, signerCount int) types.SignedHeader {
 	bitmask := makeBitmask(signerCount)
-	return types.SignedHead{
+	return types.SignedHeader{
 		Header: header,
 		SyncAggregate: types.SyncAggregate{
 			BitMask:   bitmask,

beacon/light/head_validator.go

@@ -38,10 +38,10 @@ func NewHeadValidator(committeeChain *CommitteeChain) *HeadValidator {
 type headSub struct {
 	minSignerCount int
 	nextSlot       uint64
-	callbacks      []func(types.SignedHead)
+	callbacks      []func(types.SignedHeader)
 }
 
-func (h *HeadValidator) Subscribe(minSignerCount int, callback func(types.SignedHead)) {
+func (h *HeadValidator) Subscribe(minSignerCount int, callback func(types.SignedHeader)) {
 	h.lock.Lock()
 	defer h.lock.Unlock()
 
@@ -60,15 +60,15 @@ func (h *HeadValidator) Subscribe(minSignerCount int, callback func(types.Signed
 	copy(h.subs[insertAt+1:], h.subs[insertAt:len(h.subs)-1])
 	h.subs[insertAt] = &headSub{
 		minSignerCount: minSignerCount,
-		callbacks:      []func(types.SignedHead){callback},
+		callbacks:      []func(types.SignedHeader){callback},
 	}
 }
 
-func (h *HeadValidator) Add(head types.SignedHead) error {
+func (h *HeadValidator) Add(head types.SignedHeader) error {
 	h.lock.Lock()
 	defer h.lock.Unlock()
 
-	sigOk, age := h.committeeChain.VerifySignedHead(head)
+	sigOk, age := h.committeeChain.VerifySignedHeader(head)
 	if age < 0 {
 		log.Warn("Future signed head received", "age", age)
 	}
@@ -79,7 +79,7 @@ func (h *HeadValidator) Add(head types.SignedHead) error {
 		return errors.New("invalid header signature")
 	}
 
-	signerCount := head.SignerCount()
+	signerCount := head.SyncAggregate.SignerCount()
 	for _, sub := range h.subs {
 		if sub.minSignerCount > signerCount {
 			break

beacon/light/request/head_tracker.go

@@ -33,7 +33,7 @@ import (
 // the trusted engine API while head BLS signatures are validated later as they
 // appear, in order to be passed on to other clients.
 type HeadTracker struct {
-	newSignedHead func(server *Server, signedHead types.SignedHead)
+	newSignedHead func(server *Server, signedHead types.SignedHeader)
 
 	validatedLock        sync.RWMutex
 	validatedHead        types.Header
@@ -54,7 +54,7 @@ type serverHeadInfo struct {
 
 // NewHeadTracker creates a new HeadTracker. The newSignedHead head callback is
 // called whenever a signed head is received from any of the connected servers.
-func NewHeadTracker(newSignedHead func(server *Server, signedHead types.SignedHead)) *HeadTracker {
+func NewHeadTracker(newSignedHead func(server *Server, signedHead types.SignedHeader)) *HeadTracker {
 	return &HeadTracker{
 		serverHeads:   make(map[*Server]common.Hash),
 		headInfo:      make(map[common.Hash]serverHeadInfo),
@@ -101,7 +101,7 @@ func (s *HeadTracker) registerServer(server *Server) {
 		server.setHead(slot, blockRoot)
 		s.setServerHead(server, blockRoot)
 		server.scheduler.triggerServer(server)
-	}, func(signedHead types.SignedHead) {
+	}, func(signedHead types.SignedHeader) {
 		s.newSignedHead(server, signedHead)
 	})
 }

beacon/light/request/scheduler.go

@@ -86,7 +86,7 @@ type Scheduler struct {
 
 	triggerCh          chan struct{} // restarts waiting sync loop
 	testWaitCh         chan struct{} // accepts sends when sync loop is waiting
-	testTimerCh        chan bool     // sends true when simulated timer is processed; false when stopped
+	testTimerResults   []bool        // true is appended when simulated timer is processed; false when stopped
 	triggerLock        sync.Mutex
 	waiting, triggered bool
 	trModules          map[Module]struct{}

beacon/light/request/scheduler_test.go

@@ -28,13 +28,13 @@ import (
 
 type testRequestServer struct {
 	newHead       func(uint64, common.Hash)
-	newSignedHead func(types.SignedHead)
+	newSignedHead func(types.SignedHeader)
 	clock         *mclock.Simulated
 	delayUntil    mclock.AbsTime
 	failed        bool
 }
 
-func (s *testRequestServer) SubscribeHeads(newHead func(uint64, common.Hash), newSignedHead func(types.SignedHead)) {
+func (s *testRequestServer) SubscribeHeads(newHead func(uint64, common.Hash), newSignedHead func(types.SignedHeader)) {
 	s.newHead, s.newSignedHead = newHead, newSignedHead
 }
 
@@ -89,7 +89,7 @@ func newSchedulerTest(t *testing.T, clock *mclock.Simulated, serverCount, trigge
 	st := &schedulerTest{
 		t:         t,
 		clock:     clock,
-		scheduler: NewScheduler(NewHeadTracker(func(*Server, types.SignedHead) {}), clock),
+		scheduler: NewScheduler(NewHeadTracker(func(*Server, types.SignedHeader) {}), clock),
 		modules:   make([]*testModule, len(moduleTriggers)),
 		triggers:  make([]*ModuleTrigger, triggerCount),
 		processCh: make(chan testProcess),
@@ -219,7 +219,7 @@ func (r *testRequest) returned() {
 
 func TestServerTrigger(t *testing.T) {
 	st := newSchedulerTest(t, &mclock.Simulated{}, 3, 2, [][]int{{0}, {}})
-	st.scheduler.testTimerCh = make(chan bool)
+	st.scheduler.testTimerResults = []bool{}
 	req := &testRequest{}
 	req.reqLock.Trigger = st.triggers[0]
 
@@ -251,9 +251,13 @@ func TestServerTrigger(t *testing.T) {
 	}
 
 	expectTimerFinished := func(exp bool) {
-		if processed := <-st.scheduler.testTimerCh; processed != exp {
+		if len(st.scheduler.testTimerResults) == 0 {
-			t.Fatalf("Invalid simulated timer result (got processed == %v, expected %v)", processed, exp)
+			t.Fatalf("No timer results found (expected %v)", exp)
 		}
+		if st.scheduler.testTimerResults[0] != exp {
+			t.Fatalf("Invalid simulated timer result (got finished == %v, expected %v)", st.scheduler.testTimerResults[0], exp)
+		}
+		st.scheduler.testTimerResults = st.scheduler.testTimerResults[1:]
 	}
 
 	st.servers[2].delayUntil = mclock.AbsTime(time.Second * 5)

beacon/light/request/server.go

@@ -29,7 +29,7 @@ import (
 // RequestServer is a general server interface that can be extended by modules
 // with specific request types.
 type RequestServer interface {
-	SubscribeHeads(newHead func(uint64, common.Hash), newSignedHead func(types.SignedHead))
+	SubscribeHeads(newHead func(uint64, common.Hash), newSignedHead func(types.SignedHeader))
 	UnsubscribeHeads()
 	DelayUntil() mclock.AbsTime // no requests should be sent before this
 	Fail(string)                // report server failure
@@ -49,10 +49,10 @@ type Server struct {
 	moduleData map[Module]*interface{}
 
 	lock         sync.Mutex
-	sent         map[uint64]chan struct{} // closed when returned; nil when timed out
+	timeouts     map[uint64]mclock.Timer // stopped when request has returned; nil when timed out
 	timeoutCount int
 	delayUntil   mclock.AbsTime
-	delayTimer   mclock.ChanTimer // if non-nil then expires at delayUntil
+	delayTimer   mclock.Timer // if non-nil then expires at delayUntil
 	needTrigger  bool
 	lastReqId    uint64
 	stopCh       chan struct{}
@@ -64,7 +64,7 @@ func (s *Scheduler) newServer(server RequestServer) *Server {
 		RequestServer: server,
 		scheduler:     s,
 		moduleData:    make(map[Module]*interface{}),
-		sent:          make(map[uint64]chan struct{}),
+		timeouts:      make(map[uint64]mclock.Timer),
 		stopCh:        make(chan struct{}),
 	}
 }
@@ -113,32 +113,23 @@ func (s *Server) isDelayed() bool {
 	if delayUntil == s.delayUntil {
 		return s.delayTimer != nil
 	}
-	s.delayUntil = delayUntil
 	if s.delayTimer != nil {
-		if s.delayTimer.Stop() {
+		// Note: is stopping the timer is unsuccessful then the resulting AfterFunc
-			if s.scheduler.testTimerCh != nil {
+		// call will just do nothing
-				s.scheduler.testTimerCh <- false // simulated timer stopped
+		s.stopTimer(s.delayTimer)
-			}
-		} else {
 		s.delayTimer = nil
 	}
-	}
+	s.delayUntil = delayUntil
 	delay := time.Duration(delayUntil - s.scheduler.clock.Now())
 	if delay <= 0 {
-		s.delayTimer = nil
 		return false
 	}
-	if s.delayTimer == nil {
+	s.delayTimer = s.scheduler.clock.AfterFunc(delay, func() {
-		s.delayTimer = s.scheduler.clock.NewTimer(delay)
+		if s.scheduler.testTimerResults != nil {
-	} else {
+			s.scheduler.testTimerResults = append(s.scheduler.testTimerResults, true) // simulated timer finished
-		s.delayTimer.Reset(delay)
 		}
-	timer := s.delayTimer
-	go func() {
-		select {
-		case <-timer.C():
 		s.lock.Lock()
-			if s.delayTimer == timer {
+		if s.delayTimer != nil && s.delayUntil == delayUntil { // do nothing if there is a new timer now
 			s.delayTimer = nil
 			if s.needTrigger && s.timeoutCount == 0 {
 				s.needTrigger = false
@@ -146,15 +137,7 @@ func (s *Server) isDelayed() bool {
 			}
 		}
 		s.lock.Unlock()
-			if s.scheduler.testTimerCh != nil {
+	})
-				s.scheduler.testTimerCh <- true // simulated timer processed
-			}
-		case <-s.stopCh:
-			if timer.Stop() && s.scheduler.testTimerCh != nil {
-				s.scheduler.testTimerCh <- false // simulated timer stopped
-			}
-		}
-	}()
 	return true
 }
 
@@ -166,44 +149,36 @@ func (s *Server) sendRequest(timeoutTrigger *ModuleTrigger) uint64 {
 
 	s.lastReqId++
 	reqId := s.lastReqId
-	returnCh := make(chan struct{})
+	s.timeouts[reqId] = s.scheduler.clock.AfterFunc(softRequestTimeout, func() {
-	s.sent[reqId] = returnCh
+		if s.scheduler.testTimerResults != nil {
-	timer := s.scheduler.clock.NewTimer(softRequestTimeout)
+			s.scheduler.testTimerResults = append(s.scheduler.testTimerResults, true) // simulated timer finished
-	go func() {
-		select {
-		case <-timer.C():
-			s.lock.Lock()
-			if _, ok := s.sent[reqId]; ok {
-				s.sent[reqId] = nil
-				s.timeoutCount++
 		}
-			s.lock.Unlock()
+		s.lock.Lock()
+		if s.timeouts[reqId] != nil {
+			s.timeouts[reqId] = nil
+			s.timeoutCount++
 			if timeoutTrigger != nil {
 				timeoutTrigger.Trigger()
 			}
-			if s.scheduler.testTimerCh != nil {
-				s.scheduler.testTimerCh <- true // simulated timer processed
 		}
-		case <-returnCh:
+		s.lock.Unlock()
-			if timer.Stop() && s.scheduler.testTimerCh != nil {
+	})
-				s.scheduler.testTimerCh <- false // simulated timer stopped
-			}
-		case <-s.stopCh:
-			if timer.Stop() && s.scheduler.testTimerCh != nil {
-				s.scheduler.testTimerCh <- false // simulated timer stopped
-			}
-		}
-	}()
 	return reqId
 }
 
+func (s *Server) stopTimer(timer mclock.Timer) {
+	if timer.Stop() && s.scheduler.testTimerResults != nil {
+		s.scheduler.testTimerResults = append(s.scheduler.testTimerResults, false) // simulated timer stopped
+	}
+}
+
 // hasTimedOut returns true if the given request has timed out.
 func (s *Server) hasTimedOut(reqId uint64) bool {
 	s.lock.Lock()
 	defer s.lock.Unlock()
 
-	ch, ok := s.sent[reqId]
+	timer, ok := s.timeouts[reqId]
-	return ok && ch == nil
+	return ok && timer == nil
 }
 
 // returned stops the timeout timer and removes the entry associated with the
@@ -213,9 +188,9 @@ func (s *Server) returned(reqId uint64) {
 	s.lock.Lock()
 	defer s.lock.Unlock()
 
-	if ch, ok := s.sent[reqId]; ok {
+	if timer, ok := s.timeouts[reqId]; ok {
-		if ch != nil {
+		if timer != nil {
-			close(ch)
+			s.stopTimer(timer)
 		} else {
 			s.timeoutCount--
 			if s.needTrigger && s.timeoutCount == 0 && !s.isDelayed() {
@@ -223,11 +198,18 @@ func (s *Server) returned(reqId uint64) {
 				s.scheduler.triggerServer(s)
 			}
 		}
-		delete(s.sent, reqId)
+		delete(s.timeouts, reqId)
 	}
 }
 
 // stop stops all goroutines associated with the server.
 func (s *Server) stop() {
-	close(s.stopCh)
+	for _, timer := range s.timeouts {
+		if timer != nil {
+			s.stopTimer(timer)
+		}
+	}
+	if s.delayTimer != nil {
+		s.stopTimer(s.delayTimer)
+	}
 }

beacon/light/sync/head_updater.go

@@ -31,7 +31,7 @@ type HeadUpdater struct {
 	chain          *light.CommitteeChain
 	lock           sync.Mutex
 	nextSyncPeriod uint64
-	queuedHeads    map[*request.Server][]types.SignedHead
+	queuedHeads    map[*request.Server][]types.SignedHeader
 }
 
 func NewHeadUpdater(headValidator *light.HeadValidator, chain *light.CommitteeChain) *HeadUpdater {
@@ -39,7 +39,7 @@ func NewHeadUpdater(headValidator *light.HeadValidator, chain *light.CommitteeCh
 		headValidator:  headValidator,
 		chain:          chain,
 		nextSyncPeriod: math.MaxUint64,
-		queuedHeads:    make(map[*request.Server][]types.SignedHead),
+		queuedHeads:    make(map[*request.Server][]types.SignedHeader),
 	}
 	return s
 }
@@ -49,7 +49,7 @@ func (s *HeadUpdater) SetupModuleTriggers(trigger func(id string, subscribe bool
 	trigger("newUpdate", true)
 }
 
-func (s *HeadUpdater) NewSignedHead(server *request.Server, signedHead types.SignedHead) {
+func (s *HeadUpdater) NewSignedHead(server *request.Server, signedHead types.SignedHeader) {
 	nextPeriod, ok := s.chain.NextSyncPeriod()
 	if !ok || signedHead.Header.SyncPeriod() > nextPeriod {
 		s.lock.Lock()

beacon/light/types/committee.go

@@ -30,6 +30,7 @@ import (
 
 const SerializedCommitteeSize = (params.SyncCommitteeSize + 1) * params.BlsPubkeySize
 
+// SerializedCommittee is the serialized version of a sync committee
 type SerializedCommittee [SerializedCommitteeSize]byte
 
 // jsonSyncCommittee is the JSON representation of a sync committee
@@ -137,6 +138,8 @@ type SyncCommittee struct {
 	aggregate *bls.Pubkey
 }
 
+// VerifySignature returns true if the given sync aggregate is a valid signature
+// or the given hash
 func (sc *SyncCommittee) VerifySignature(signingRoot common.Hash, aggregate *SyncAggregate) bool {
 	var (
 		sig         bls.Signature
@@ -195,6 +198,7 @@ func (s *SyncAggregate) UnmarshalJSON(input []byte) error {
 	return nil
 }
 
+// SignerCount returns the number of signers in the aggregate signature
 func (s *SyncAggregate) SignerCount() int {
 	var count int
 	for _, v := range s.BitMask {

beacon/light/types/forks.go

@@ -32,6 +32,8 @@ import (
 	"github.com/minio/sha256-simd"
 )
 
+const syncCommitteeDomain = 7
+
 // Fork describes a single beacon chain fork and also stores the calculated
 // signature domain used after this fork.
 type Fork struct {
@@ -79,7 +81,7 @@ func computeDomain(forkVersion []byte, genesisValidatorsRoot common.Hash) merkle
 	hasher.Write(forkVersion32[:])
 	hasher.Write(genesisValidatorsRoot[:])
 	hasher.Sum(forkDataRoot[:0])
-	domain[0] = 7
+	domain[0] = syncCommitteeDomain
 	copy(domain[4:], forkDataRoot[:28])
 	return domain
 }

beacon/light/types/header.go

@@ -108,53 +108,13 @@ func PeriodOfSlot(slot uint64) uint64 {
 	return slot >> params.Log2SyncPeriodLength
 }
 
-// HeaderWithoutState stores beacon header fields except the state root which can
+// SignedHeader represents a beacon header signed by a sync committee
-// be reconstructed from a partial beacon state proof stored alongside the header
-type HeaderWithoutState struct {
-	Slot                 uint64
-	ProposerIndex        uint64
-	ParentRoot, BodyRoot common.Hash
-}
-
-// Hash calculates the block root of the header
-func (bh *HeaderWithoutState) Hash(stateRoot common.Hash) common.Hash {
-	return bh.Proof(stateRoot).RootHash()
-}
-
-// Proof returns a MultiProof of the header
-func (bh *HeaderWithoutState) Proof(stateRoot common.Hash) merkle.MultiProof {
-	var values [8]merkle.Value // values corresponding to indices 8 to 15 of the beacon header tree
-	binary.LittleEndian.PutUint64(values[params.BhiSlot-8][:8], bh.Slot)
-	binary.LittleEndian.PutUint64(values[params.BhiProposerIndex-8][:8], bh.ProposerIndex)
-	values[params.BhiParentRoot-8] = merkle.Value(bh.ParentRoot)
-	values[params.BhiStateRoot-8] = merkle.Value(stateRoot)
-	values[params.BhiBodyRoot-8] = merkle.Value(bh.BodyRoot)
-	return merkle.MultiProof{Format: headerFormat, Values: values[:]}
-}
-
-// FullHeader reconstructs a full Header from a HeaderWithoutState and a state root
-func (bh *HeaderWithoutState) FullHeader(stateRoot common.Hash) Header {
-	return Header{
-		Slot:          bh.Slot,
-		ProposerIndex: bh.ProposerIndex,
-		ParentRoot:    bh.ParentRoot,
-		StateRoot:     stateRoot,
-		BodyRoot:      bh.BodyRoot,
-	}
-}
-
-// SignedHead represents a beacon header signed by a sync committee
 //
 // Note: this structure is created from either an optimistic update or an instant update:
 //  https://github.com/ethereum/consensus-specs/blob/dev/specs/altair/light-client/sync-protocol.md#lightclientoptimisticupdate
 //  https://github.com/zsfelfoldi/beacon-APIs/blob/instant_update/apis/beacon/light_client/instant_update.yaml
-type SignedHead struct {
+type SignedHeader struct {
 	Header        Header        // signed beacon header
 	SyncAggregate SyncAggregate // sync committee signature aggregate
 	SignatureSlot uint64        // slot in which the signature has been created (newer than Header.Slot, determines the signing sync committee)
 }
-
-// SignerCount returns the number of individual signers in the signature aggregate
-func (s *SignedHead) SignerCount() int {
-	return s.SyncAggregate.SignerCount()
-}

beacon/light/types/protocol.go

@@ -26,8 +26,6 @@ import (
 	"github.com/ethereum/go-ethereum/log"
 )
 
-const MaxUpdateScoresLength = 128 // max number of advertised update scores of most recent periods
-
 // LightClientUpdate is a proof of the next sync committee root based on a header
 // signed by the sync committee of the given period. Optionally the update can
 // prove quasi-finality by the signed header referring to a previous, finalized
@@ -37,9 +35,7 @@ const MaxUpdateScoresLength = 128 // max number of advertised update scores of m
 // See data structure definition here:
 // https://github.com/ethereum/consensus-specs/blob/dev/specs/altair/light-client/sync-protocol.md#lightclientupdate
 type LightClientUpdate struct {
-	Header                  Header
+	SignedHeader
-	SyncAggregate           SyncAggregate
-	SignatureSlot           uint64
 	NextSyncCommitteeRoot   common.Hash
 	NextSyncCommitteeBranch merkle.Values
 	FinalizedHeader         Header
@@ -83,7 +79,7 @@ func (u *CommitteeUpdate) MarshalJSON() ([]byte, error) {
 			Header:                  JsonBeaconHeader{Beacon: u.Update.Header},
 			NextSyncCommittee:       u.NextSyncCommittee,
 			NextSyncCommitteeBranch: u.Update.NextSyncCommitteeBranch,
-			FinalizedHeader:         JsonBeaconHeader{Beacon: u.Update.FinalizedHeader}, //TODO should we encode it when not present?
+			FinalizedHeader:         JsonBeaconHeader{Beacon: u.Update.FinalizedHeader},
 			FinalityBranch:          u.Update.FinalityBranch,
 			SyncAggregate:           u.Update.SyncAggregate,
 			SignatureSlot:           common.Decimal(u.Update.SignatureSlot),
@@ -100,9 +96,11 @@ func (u *CommitteeUpdate) UnmarshalJSON(input []byte) error {
 	u.Version = dec.Version
 	u.NextSyncCommittee = dec.Data.NextSyncCommittee
 	u.Update = &LightClientUpdate{
+		SignedHeader: SignedHeader{
 			Header:        dec.Data.Header.Beacon,
 			SyncAggregate: dec.Data.SyncAggregate,
 			SignatureSlot: uint64(dec.Data.SignatureSlot),
+		},
 		NextSyncCommitteeRoot:   u.NextSyncCommittee.Root(),
 		NextSyncCommitteeBranch: dec.Data.NextSyncCommitteeBranch,
 		FinalizedHeader:         dec.Data.FinalizedHeader.Beacon,
@@ -196,20 +194,6 @@ type PeriodRange struct {
 	First, AfterLast uint64
 }
 
-/*func (a PeriodRange) Shared(b PeriodRange) PeriodRange {
-	if b.First > a.First {
-		a.First = b.First
-	}
-	if b.AfterLast < a.AfterLast {
-		a.AfterLast = b.AfterLast
-	}
-	return a
-}
-
-func (a PeriodRange) IsValid() bool {
-	return a.AfterLast >= a.First
-}*/
-
 func (a PeriodRange) IsEmpty() bool {
 	return a.AfterLast == a.First
 }

cmd/blsync/main.go

@@ -108,7 +108,7 @@ func blsync(ctx *cli.Context) error {
 	committeeChain.SetGenesisData(chainConfig.GenesisData)
 	headUpdater := sync.NewHeadUpdater(headValidator, committeeChain)
 	headTracker := request.NewHeadTracker(headUpdater.NewSignedHead)
-	headValidator.Subscribe(threshold, func(signedHead types.SignedHead) {
+	headValidator.Subscribe(threshold, func(signedHead types.SignedHeader) {
 		headTracker.SetValidatedHead(signedHead.Header)
 	})