Merge branch 'develop' of https://github.com/prysmaticlabs/geth-sharding into hackSync

* Fix Bugs

* Remove log

beacon-chain/blockchain/BUILD.bazel

@@ -12,6 +12,7 @@ go_library(
         "forkchoice_update_execution.go",
         "head.go",
         "head_sync_committee_info.go",
+        "holeskyhack.go",
         "init_sync_process_block.go",
         "log.go",
         "merge_ascii_art.go",

beacon-chain/blockchain/holeskyhack.go

@@ -0,0 +1,21 @@
+package blockchain
+
+import (
+	"encoding/hex"
+
+	"github.com/pkg/errors"
+)
+
+var errHoleskyForbiddenRoot = errors.New("refusing to process forbidden holesky block")
+
+// hack to prevent bad holesky block importation
+var badHoleskyRoot [32]byte
+
+func init() {
+	hexStr := "2db899881ed8546476d0b92c6aa9110bea9a4cd0dbeb5519eb0ea69575f1f359"
+	bytes, err := hex.DecodeString(hexStr)
+	if err != nil {
+		panic(err)
+	}
+	badHoleskyRoot = [32]byte(bytes)
+}

beacon-chain/blockchain/process_block.go

@@ -173,6 +173,9 @@ func (s *Service) onBlockBatch(ctx context.Context, blks []consensusblocks.ROBlo
 	var set *bls.SignatureBatch
 	boundaries := make(map[[32]byte]state.BeaconState)
 	for i, b := range blks {
+		if b.Root() == badHoleskyRoot {
+			return errHoleskyForbiddenRoot
+		}
 		v, h, err := getStateVersionAndPayload(preState)
 		if err != nil {
 			return err

beacon-chain/blockchain/receive_block.go

@@ -64,6 +64,11 @@ type SlashingReceiver interface {
 func (s *Service) ReceiveBlock(ctx context.Context, block interfaces.ReadOnlySignedBeaconBlock, blockRoot [32]byte, avs das.AvailabilityStore) error {
 	ctx, span := trace.StartSpan(ctx, "blockChain.ReceiveBlock")
 	defer span.End()
+
+	if blockRoot == badHoleskyRoot {
+		return errHoleskyForbiddenRoot
+	}
+
 	// Return early if the block has been synced
 	if s.InForkchoice(blockRoot) {
 		log.WithField("blockRoot", fmt.Sprintf("%#x", blockRoot)).Debug("Ignoring already synced block")

beacon-chain/blockchain/service.go

@@ -39,6 +39,7 @@ import (
 	ethpb "github.com/prysmaticlabs/prysm/v5/proto/prysm/v1alpha1"
 	prysmTime "github.com/prysmaticlabs/prysm/v5/time"
 	"github.com/prysmaticlabs/prysm/v5/time/slots"
+	"github.com/sirupsen/logrus"
 )
 
 // Service represents a service that handles the internal
@@ -316,33 +317,40 @@ func (s *Service) originRootFromSavedState(ctx context.Context) ([32]byte, error
 	return genesisBlkRoot, nil
 }
 
-// initializeHeadFromDB uses the finalized checkpoint and head block found in the database to set the current head.
+// initializeHeadFromDB uses the finalized checkpoint and head block root from forkchoice to set the current head.
 // Note that this may block until stategen replays blocks between the finalized and head blocks
 // if the head sync flag was specified and the gap between the finalized and head blocks is at least 128 epochs long.
-func (s *Service) initializeHeadFromDB(ctx context.Context, finalizedState state.BeaconState) error {
+func (s *Service) initializeHead(ctx context.Context, st state.BeaconState) error {
 	cp := s.FinalizedCheckpt()
-	fRoot := [32]byte(cp.Root)
+	fRoot := s.ensureRootNotZeros([32]byte(cp.Root))
-	finalizedRoot := s.ensureRootNotZeros(fRoot)
+	if st == nil || st.IsNil() {
-
-	if finalizedState == nil || finalizedState.IsNil() {
 		return errors.New("finalized state can't be nil")
 	}
 
-	finalizedBlock, err := s.getBlock(ctx, finalizedRoot)
+	s.cfg.ForkChoiceStore.RLock()
+	root := s.cfg.ForkChoiceStore.HighestReceivedBlockRoot()
+	s.cfg.ForkChoiceStore.RUnlock()
+	blk, err := s.cfg.BeaconDB.Block(ctx, root)
 	if err != nil {
-		return errors.Wrap(err, "could not get finalized block")
+		return errors.Wrap(err, "could not get head block")
 	}
-	if err := s.setHead(&head{
+	if root != fRoot {
-		finalizedRoot,
+		st, err = s.cfg.StateGen.StateByRoot(ctx, root)
-		finalizedBlock,
+		if err != nil {
-		finalizedState,
+			return errors.Wrap(err, "could not get head state")
-		finalizedBlock.Block().Slot(),
+		}
+	}
+	log.WithFields(logrus.Fields{
+		"root": fmt.Sprintf("%#x", root),
+		"slot": blk.Block().Slot(),
+	}).Info("Initialized head block from DB")
+	return errors.Wrap(s.setHead(&head{
+		root,
+		blk,
+		st,
+		blk.Block().Slot(),
 		false,
-	}); err != nil {
+	}), "could not set head")
-		return errors.Wrap(err, "could not set head")
-	}
-
-	return nil
 }
 
 func (s *Service) startFromExecutionChain() error {

beacon-chain/blockchain/setup_forchoice.go

@@ -2,28 +2,131 @@ package blockchain
 
 import (
 	"bytes"
+	"context"
+	"fmt"
 
 	"github.com/pkg/errors"
 	forkchoicetypes "github.com/prysmaticlabs/prysm/v5/beacon-chain/forkchoice/types"
 	"github.com/prysmaticlabs/prysm/v5/beacon-chain/state"
 	"github.com/prysmaticlabs/prysm/v5/config/features"
 	"github.com/prysmaticlabs/prysm/v5/consensus-types/blocks"
+	"github.com/prysmaticlabs/prysm/v5/consensus-types/interfaces"
 	"github.com/prysmaticlabs/prysm/v5/encoding/bytesutil"
+	"github.com/prysmaticlabs/prysm/v5/time/slots"
 )
 
 func (s *Service) setupForkchoice(st state.BeaconState) error {
 	if err := s.setupForkchoiceCheckpoints(); err != nil {
 		return errors.Wrap(err, "could not set up forkchoice checkpoints")
 	}
-	if err := s.setupForkchoiceRoot(st); err != nil {
+	if err := s.setupForkchoiceTree(st); err != nil {
 		return errors.Wrap(err, "could not set up forkchoice root")
 	}
-	if err := s.initializeHeadFromDB(s.ctx, st); err != nil {
+	if err := s.initializeHead(s.ctx, st); err != nil {
 		return errors.Wrap(err, "could not initialize head from db")
 	}
 	return nil
 }
 
+func (s *Service) startupHeadRoot() [32]byte {
+	headStr := features.Get().ForceHead
+	cp := s.FinalizedCheckpt()
+	fRoot := s.ensureRootNotZeros([32]byte(cp.Root))
+	if headStr == "" {
+		return fRoot
+	}
+	if headStr == "head" {
+		root, err := s.cfg.BeaconDB.HeadBlockRoot()
+		if err != nil {
+			log.WithError(err).Error("could not get head block root, starting with finalized block as head")
+			return fRoot
+		}
+		log.Infof("Using Head root of %#x", root)
+		return root
+	}
+	root, err := bytesutil.DecodeHexWithLength(headStr, 32)
+	if err != nil {
+		log.WithError(err).Error("could not parse head root, starting with finalized block as head")
+		return fRoot
+	}
+	return [32]byte(root)
+}
+
+func (s *Service) setupForkchoiceTree(st state.BeaconState) error {
+	headRoot := s.startupHeadRoot()
+	cp := s.FinalizedCheckpt()
+	fRoot := s.ensureRootNotZeros([32]byte(cp.Root))
+	if err := s.setupForkchoiceRoot(st); err != nil {
+		return errors.Wrap(err, "could not set up forkchoice root")
+	}
+	fBlk, err := s.cfg.BeaconDB.Block(s.ctx, fRoot)
+	if err != nil {
+		return errors.Wrap(err, "could not get finalized block")
+	}
+	if err := s.setHead(&head{
+		fRoot,
+		fBlk,
+		st,
+		fBlk.Block().Slot(),
+		false,
+	}); err != nil {
+		return errors.Wrap(err, "could not set head")
+	}
+
+	if headRoot == fRoot {
+		return nil
+	}
+	blk, err := s.cfg.BeaconDB.Block(s.ctx, headRoot)
+	if err != nil {
+		log.WithError(err).Error("could not get head block, starting with finalized block as head")
+		return nil
+	}
+	if slots.ToEpoch(blk.Block().Slot()) < cp.Epoch {
+		log.WithField("headRoot", fmt.Sprintf("%#x", headRoot)).Error("head block is older than finalized block, starting with finalized block as head")
+		return nil
+	}
+	chain, err := s.buildForkchoiceChain(s.ctx, blk)
+	if err != nil {
+		log.WithError(err).Error("could not build forkchoice chain, starting with finalized block as head")
+		return nil
+	}
+	s.cfg.ForkChoiceStore.Lock()
+	defer s.cfg.ForkChoiceStore.Unlock()
+	return s.cfg.ForkChoiceStore.InsertChain(s.ctx, chain)
+}
+
+func (s *Service) buildForkchoiceChain(ctx context.Context, head interfaces.ReadOnlySignedBeaconBlock) ([]*forkchoicetypes.BlockAndCheckpoints, error) {
+	chain := []*forkchoicetypes.BlockAndCheckpoints{}
+	cp := s.FinalizedCheckpt()
+	fRoot := s.ensureRootNotZeros([32]byte(cp.Root))
+	jp := s.CurrentJustifiedCheckpt()
+	root, err := head.Block().HashTreeRoot()
+	if err != nil {
+		return nil, errors.Wrap(err, "could not get head block root")
+	}
+	for {
+		roblock, err := blocks.NewROBlockWithRoot(head, root)
+		if err != nil {
+			return nil, err
+		}
+		// This chain sets the justified checkpoint for every block, including some that are older than jp.
+		// This should be however safe for forkchoice at startup.
+		chain = append(chain, &forkchoicetypes.BlockAndCheckpoints{Block: roblock, JustifiedCheckpoint: jp, FinalizedCheckpoint: cp})
+		root = head.Block().ParentRoot()
+		if root == fRoot {
+			break
+		}
+		head, err = s.cfg.BeaconDB.Block(s.ctx, root)
+		if err != nil {
+			return nil, errors.Wrap(err, "could not get block")
+		}
+		if slots.ToEpoch(head.Block().Slot()) < cp.Epoch {
+			return nil, errors.New("head block is not a descendant of the finalized checkpoint")
+		}
+	}
+	return chain, nil
+}
+
 func (s *Service) setupForkchoiceRoot(st state.BeaconState) error {
 	cp := s.FinalizedCheckpt()
 	fRoot := s.ensureRootNotZeros([32]byte(cp.Root))

beacon-chain/db/iface/interface.go

@@ -110,6 +110,7 @@ type HeadAccessDatabase interface {
 
 	// Block related methods.
 	HeadBlock(ctx context.Context) (interfaces.ReadOnlySignedBeaconBlock, error)
+	HeadBlockRoot() ([32]byte, error)
 	SaveHeadBlockRoot(ctx context.Context, blockRoot [32]byte) error
 
 	// Genesis operations.

beacon-chain/db/kv/blocks.go

@@ -70,6 +70,21 @@ func (s *Store) OriginCheckpointBlockRoot(ctx context.Context) ([32]byte, error)
 	return root, err
 }
 
+// HeadBlockRoot returns the latest canonical block root in the Ethereum Beacon Chain.
+func (s *Store) HeadBlockRoot() ([32]byte, error) {
+	var root [32]byte
+	err := s.db.View(func(tx *bolt.Tx) error {
+		bkt := tx.Bucket(blocksBucket)
+		headRoot := bkt.Get(headBlockRootKey)
+		if headRoot == nil {
+			return errors.New("no head block root found")
+		}
+		copy(root[:], headRoot)
+		return nil
+	})
+	return root, err
+}
+
 // HeadBlock returns the latest canonical block in the Ethereum Beacon Chain.
 func (s *Store) HeadBlock(ctx context.Context) (interfaces.ReadOnlySignedBeaconBlock, error) {
 	ctx, span := trace.StartSpan(ctx, "BeaconDB.HeadBlock")
@@ -214,7 +229,8 @@ func (s *Store) DeleteBlock(ctx context.Context, root [32]byte) error {
 	defer span.End()
 
 	if err := s.DeleteState(ctx, root); err != nil {
-		return err
+		// TODO: Find out why invalid states are in the db
+		log.WithError(err).Error("Could not delete state")
 	}
 
 	if err := s.deleteStateSummary(root); err != nil {

beacon-chain/forkchoice/doubly-linked-tree/store.go

@@ -252,6 +252,13 @@ func (s *Store) tips() ([][32]byte, []primitives.Slot) {
 	return roots, slots
 }
 
+func (f *ForkChoice) HighestReceivedBlockRoot() [32]byte {
+	if f.store.highestReceivedNode == nil {
+		return [32]byte{}
+	}
+	return f.store.highestReceivedNode.root
+}
+
 // HighestReceivedBlockSlot returns the highest slot received by the forkchoice
 func (f *ForkChoice) HighestReceivedBlockSlot() primitives.Slot {
 	if f.store.highestReceivedNode == nil {

beacon-chain/forkchoice/interfaces.go

@@ -65,6 +65,7 @@ type FastGetter interface {
 	FinalizedPayloadBlockHash() [32]byte
 	HasNode([32]byte) bool
 	HighestReceivedBlockSlot() primitives.Slot
+	HighestReceivedBlockRoot() [32]byte
 	HighestReceivedBlockDelay() primitives.Slot
 	IsCanonical(root [32]byte) bool
 	IsOptimistic(root [32]byte) (bool, error)

beacon-chain/forkchoice/ro.go

@@ -114,6 +114,13 @@ func (ro *ROForkChoice) HighestReceivedBlockSlot() primitives.Slot {
 	return ro.getter.HighestReceivedBlockSlot()
 }
 
+// HighestReceivedBlockRoot delegates to the underlying forkchoice call, under a lock.
+func (ro *ROForkChoice) HighestReceivedBlockRoot() [32]byte {
+	ro.l.RLock()
+	defer ro.l.RUnlock()
+	return ro.getter.HighestReceivedBlockRoot()
+}
+
 // HighestReceivedBlockDelay delegates to the underlying forkchoice call, under a lock.
 func (ro *ROForkChoice) HighestReceivedBlockDelay() primitives.Slot {
 	ro.l.RLock()

beacon-chain/forkchoice/ro_test.go

@@ -29,6 +29,7 @@ const (
 	unrealizedJustifiedPayloadBlockHashCalled
 	nodeCountCalled
 	highestReceivedBlockSlotCalled
+	highestReceivedBlockRootCalled
 	highestReceivedBlockDelayCalled
 	receivedBlocksLastEpochCalled
 	weightCalled
@@ -252,6 +253,11 @@ func (ro *mockROForkchoice) HighestReceivedBlockSlot() primitives.Slot {
 	return 0
 }
 
+func (ro *mockROForkchoice) HighestReceivedBlockRoot() [32]byte {
+	ro.calls = append(ro.calls, highestReceivedBlockRootCalled)
+	return [32]byte{}
+}
+
 func (ro *mockROForkchoice) HighestReceivedBlockDelay() primitives.Slot {
 	ro.calls = append(ro.calls, highestReceivedBlockDelayCalled)
 	return 0

beacon-chain/operations/attestations/kv/unaggregated.go

@@ -9,6 +9,7 @@ import (
 	ethpb "github.com/prysmaticlabs/prysm/v5/proto/prysm/v1alpha1"
 	"github.com/prysmaticlabs/prysm/v5/proto/prysm/v1alpha1/attestation"
 	"github.com/prysmaticlabs/prysm/v5/runtime/version"
+	log "github.com/sirupsen/logrus"
 )
 
 // SaveUnaggregatedAttestation saves an unaggregated attestation in cache.
@@ -60,7 +61,8 @@ func (c *AttCaches) UnaggregatedAttestations() ([]ethpb.Att, error) {
 	for _, att := range unAggregatedAtts {
 		seen, err := c.hasSeenBit(att)
 		if err != nil {
-			return nil, err
+			log.WithError(err).Debug("Could not check if attestations bits have been seen")
+			continue
 		}
 		if !seen {
 			atts = append(atts, att.Clone())
@@ -163,7 +165,13 @@ func (c *AttCaches) DeleteSeenUnaggregatedAttestations() (int, error) {
 		if att == nil || att.IsNil() || att.IsAggregated() {
 			continue
 		}
-		if seen, err := c.hasSeenBit(att); err == nil && seen {
+		seen, err := c.hasSeenBit(att)
+		if err != nil {
+			log.WithError(err).Debug("Could not check if attestations bits have been seen")
+			delete(c.unAggregatedAtt, r)
+			count++
+		}
+		if seen {
 			delete(c.unAggregatedAtt, r)
 			count++
 		}

beacon-chain/rpc/prysm/v1alpha1/validator/proposer_attestations.go

@@ -39,13 +39,6 @@ func (vs *Server) packAttestations(ctx context.Context, latestState state.Beacon
 	} else {
 		atts = vs.AttPool.AggregatedAttestations()
 		atts = vs.validateAndDeleteAttsInPool(ctx, latestState, atts)
-
-		uAtts, err := vs.AttPool.UnaggregatedAttestations()
-		if err != nil {
-			return nil, errors.Wrap(err, "could not get unaggregated attestations")
-		}
-		uAtts = vs.validateAndDeleteAttsInPool(ctx, latestState, uAtts)
-		atts = append(atts, uAtts...)
 	}
 
 	// Checking the state's version here will give the wrong result if the last slot of Deneb is missed.

beacon-chain/sync/initial-sync/BUILD.bazel

@@ -38,6 +38,7 @@ go_library(
         "//consensus-types/primitives:go_default_library",
         "//container/leaky-bucket:go_default_library",
         "//crypto/rand:go_default_library",
+        "//encoding/bytesutil:go_default_library",
         "//math:go_default_library",
         "//monitoring/tracing/trace:go_default_library",
         "//proto/prysm/v1alpha1:go_default_library",

beacon-chain/sync/initial-sync/blocks_fetcher.go

@@ -2,6 +2,7 @@ package initialsync
 
 import (
 	"context"
+	"encoding/hex"
 	"fmt"
 	"sort"
 	"strings"
@@ -24,6 +25,7 @@ import (
 	"github.com/prysmaticlabs/prysm/v5/consensus-types/primitives"
 	leakybucket "github.com/prysmaticlabs/prysm/v5/container/leaky-bucket"
 	"github.com/prysmaticlabs/prysm/v5/crypto/rand"
+	"github.com/prysmaticlabs/prysm/v5/encoding/bytesutil"
 	"github.com/prysmaticlabs/prysm/v5/math"
 	"github.com/prysmaticlabs/prysm/v5/monitoring/tracing/trace"
 	p2ppb "github.com/prysmaticlabs/prysm/v5/proto/prysm/v1alpha1"
@@ -67,6 +69,8 @@ var (
 // Period to calculate expected limit for a single peer.
 var blockLimiterPeriod = 30 * time.Second
 
+type isBannedBlock func(root [32]byte) bool
+
 // blocksFetcherConfig is a config to setup the block fetcher.
 type blocksFetcherConfig struct {
 	clock                    *startup.Clock
@@ -101,6 +105,7 @@ type blocksFetcher struct {
 	capacityWeight  float64       // how remaining capacity affects peer selection
 	mode            syncMode      // allows to use fetcher in different sync scenarios
 	quit            chan struct{} // termination notifier
+	isBannedBlock   isBannedBlock
 }
 
 // peerLock restricts fetcher actions on per peer basis. Currently, used for rate limiting.
@@ -126,6 +131,13 @@ type fetchRequestResponse struct {
 	err   error
 }
 
+// set in init()
+var holeskyBadRoot [32]byte
+
+func isHoleskyBannedBlock(root [32]byte) bool {
+	return root == holeskyBadRoot
+}
+
 // newBlocksFetcher creates ready to use fetcher.
 func newBlocksFetcher(ctx context.Context, cfg *blocksFetcherConfig) *blocksFetcher {
 	blockBatchLimit := maxBatchLimit()
@@ -160,6 +172,7 @@ func newBlocksFetcher(ctx context.Context, cfg *blocksFetcherConfig) *blocksFetc
 		capacityWeight:  capacityWeight,
 		mode:            cfg.mode,
 		quit:            make(chan struct{}),
+		isBannedBlock:   isHoleskyBannedBlock,
 	}
 }
 
@@ -357,6 +370,13 @@ func (f *blocksFetcher) fetchBlocksFromPeer(
 			log.WithField("peer", p).WithError(err).Debug("invalid BeaconBlocksByRange response")
 			continue
 		}
+		if f.isBannedBlock != nil {
+			for _, b := range robs {
+				if f.isBannedBlock(b.Block.Root()) {
+					return nil, p, prysmsync.ErrInvalidFetchedData
+				}
+			}
+		}
 		return robs, p, err
 	}
 	return nil, "", errNoPeersAvailable
@@ -727,3 +747,11 @@ func dedupPeers(peers []peer.ID) []peer.ID {
 	}
 	return newPeerList
 }
+
+func init() {
+	bytes, err := hex.DecodeString("2db899881ed8546476d0b92c6aa9110bea9a4cd0dbeb5519eb0ea69575f1f359")
+	if err != nil {
+		panic(err)
+	}
+	holeskyBadRoot = bytesutil.ToBytes32(bytes)
+}

beacon-chain/sync/initial-sync/round_robin.go

@@ -125,6 +125,7 @@ func (s *Service) syncToNonFinalizedEpoch(ctx context.Context, genesis time.Time
 	if err != nil {
 		return err
 	}
+
 	for data := range queue.fetchedData {
 		s.processFetchedDataRegSync(ctx, genesis, s.cfg.Chain.HeadSlot(), data)
 	}
@@ -169,6 +170,7 @@ func (s *Service) processFetchedDataRegSync(
 		"firstSlot":        data.bwb[0].Block.Block().Slot(),
 		"firstUnprocessed": bwb[0].Block.Block().Slot(),
 	}
+
 	for _, b := range bwb {
 		if err := avs.Persist(s.clock.CurrentSlot(), b.Blobs...); err != nil {
 			log.WithError(err).WithFields(batchFields).WithFields(syncFields(b.Block)).Warn("Batch failure due to BlobSidecar issues")

beacon-chain/sync/service.go

@@ -6,6 +6,7 @@ package sync
 
 import (
 	"context"
+	"encoding/hex"
 	"sync"
 	"time"
 
@@ -49,6 +50,9 @@ import (
 	"github.com/prysmaticlabs/prysm/v5/time/slots"
 )
 
+// hack to prevent bad holesky block importation
+var badHoleskyRoot [32]byte
+
 var _ runtime.Service = (*Service)(nil)
 
 const (
@@ -383,3 +387,13 @@ type Checker interface {
 	Status() error
 	Resync() error
 }
+
+func init() {
+	hexStr := "2db899881ed8546476d0b92c6aa9110bea9a4cd0dbeb5519eb0ea69575f1f359"
+	bytes, err := hex.DecodeString(hexStr)
+	if err != nil {
+		log.WithError(err).Error("Could not decode hex string")
+		return
+	}
+	badHoleskyRoot = [32]byte(bytes)
+}

beacon-chain/sync/validate_beacon_blocks.go

@@ -399,6 +399,9 @@ func (s *Service) setSeenBlockIndexSlot(slot primitives.Slot, proposerIdx primit
 
 // Returns true if the block is marked as a bad block.
 func (s *Service) hasBadBlock(root [32]byte) bool {
+	if root == badHoleskyRoot {
+		return true
+	}
 	s.badBlockLock.RLock()
 	defer s.badBlockLock.RUnlock()
 	_, seen := s.badBlockCache.Get(string(root[:]))

changelog/potuz_sync_from_head.md

@@ -0,0 +1,3 @@
+### Added
+
+- Added a feature flag to sync from an arbitrary beacon block root at startup. 

config/features/config.go

@@ -86,6 +86,9 @@ type Flags struct {
 
 	// AggregateIntervals specifies the time durations at which we aggregate attestations preparing for forkchoice.
 	AggregateIntervals [3]time.Duration
+
+	// Feature related flags (alignment forced in the end)
+	ForceHead string // ForceHead forces the head block to be a specific block root, the last head block, or the last finalized block.
 }
 
 var featureConfig *Flags
@@ -268,6 +271,10 @@ func ConfigureBeaconChain(ctx *cli.Context) error {
 		logEnabled(enableExperimentalAttestationPool)
 		cfg.EnableExperimentalAttestationPool = true
 	}
+	if ctx.IsSet(forceHeadFlag.Name) {
+		logEnabled(forceHeadFlag)
+		cfg.ForceHead = ctx.String(forceHeadFlag.Name)
+	}
 
 	cfg.AggregateIntervals = [3]time.Duration{aggregateFirstInterval.Value, aggregateSecondInterval.Value, aggregateThirdInterval.Value}
 	Init(cfg)

config/features/flags.go

@@ -174,6 +174,12 @@ var (
 		Name:  "enable-experimental-attestation-pool",
 		Usage: "Enables an experimental attestation pool design.",
 	}
+	// forceHeadFlag is a flag to force the head of the beacon chain to a specific block.
+	forceHeadFlag = &cli.StringFlag{
+		Name: "sync-from",
+		Usage: "Forces the head of the beacon chain to a specific block root. Values can be 'head' or a block root." +
+			" The block root has to be known to the beacon node and correspond to a block newer than the current finalized checkpoint.",
+	}
 )
 
 // devModeFlags holds list of flags that are set when development mode is on.
@@ -230,6 +236,7 @@ var BeaconChainFlags = combinedFlags([]cli.Flag{
 	DisableCommitteeAwarePacking,
 	EnableDiscoveryReboot,
 	enableExperimentalAttestationPool,
+	forceHeadFlag,
 }, deprecatedBeaconFlags, deprecatedFlags, upcomingDeprecation)
 
 func combinedFlags(flags ...[]cli.Flag) []cli.Flag {

config/params/testnet_holesky_config.go

@@ -7,15 +7,10 @@ func UseHoleskyNetworkConfig() {
 	cfg := BeaconNetworkConfig().Copy()
 	cfg.ContractDeploymentBlock = 0
 	cfg.BootstrapNodes = []string{
-		// EF
+		"enr:-Oa4QOuWj-_JX6iJWjdS_67qQkkVoomo3YztvdOLVF4lVwc3NzFR3D8y-8CmGjmQA16DJBOZWwbc3XMOw_w_ScU6-qCCAgSHYXR0bmV0c4gAAAMAAAAAAIZjbGllbnTYikxpZ2h0aG91c2WMNy4wLjAtYmV0YS4whGV0aDKQAZ4hrQYBcAD__________4JpZIJ2NIJpcISyE90mhHF1aWOCfLuJc2VjcDI1NmsxoQK-fTVglh3wyHIcyauubuyvLeFmn6QpUwog7Aio2OSucYhzeW5jbmV0cwCDdGNwgny6g3VkcIJ8ug",
-		"enr:-Ku4QFo-9q73SspYI8cac_4kTX7yF800VXqJW4Lj3HkIkb5CMqFLxciNHePmMt4XdJzHvhrCC5ADI4D_GkAsxGJRLnQBh2F0dG5ldHOIAAAAAAAAAACEZXRoMpAhnTT-AQFwAP__________gmlkgnY0gmlwhLKAiOmJc2VjcDI1NmsxoQORcM6e19T1T9gi7jxEZjk_sjVLGFscUNqAY9obgZaxbIN1ZHCCIyk",
+		"enr:-PW4QAOnzqnCuwuNNrUEXebSD3MFMOe-9NApsb8UkAQK-MquYtUhj35Ksz4EWcmdB0Cmj43bGBJJEpt9fYMAg1vOHXobh2F0dG5ldHOIAAAYAAAAAACGY2xpZW502IpMaWdodGhvdXNljDcuMC4wLWJldGEuMIRldGgykAGeIa0GAXAA__________-CaWSCdjSCaXCEff1tSYRxdWljgiMphXF1aWM2giMpiXNlY3AyNTZrMaECUiAFSBathSIPGhDHbZjQS5gTqaPcRkAe4HECCk-vt6KIc3luY25ldHMPg3RjcIIjKIR0Y3A2giMog3VkcIIjKA",
-		"enr:-Ku4QPG7F72mbKx3gEQEx07wpYYusGDh-ni6SNkLvOS-hhN-BxIggN7tKlmalb0L5JPoAfqD-akTZ-gX06hFeBEz4WoBh2F0dG5ldHOIAAAAAAAAAACEZXRoMpAhnTT-AQFwAP__________gmlkgnY0gmlwhJK-DYCJc2VjcDI1NmsxoQKLVXFOhp2uX6jeT0DvvDpPcU8FWMjQdR4wMuORMhpX24N1ZHCCIyk",
+		"enr:-QESuEA2tFgFDu5LX9T6j1_bayowdRzrtdQcjwmTq_zOVjwe1WQOsM7-Q4qRcgc7AjpAQOcdb2F3wyPDBkbP-vxW2dLgXYdhdHRuZXRziAADAAAAAAAAhmNsaWVudNiKTGlnaHRob3VzZYw3LjAuMC1iZXRhLjCEZXRoMpABniGtBgFwAP__________gmlkgnY0gmlwhIe1ME2DaXA2kCoBBPkwgDCeAAAAAAAAAAKEcXVpY4IjKYVxdWljNoIjg4lzZWNwMjU2azGhA4oHjOmlWOfLizFFIQSI_dzn4rzvDvMG8h7zmxhmOVzXiHN5bmNuZXRzD4N0Y3CCIyiEdGNwNoIjgoN1ZHCCIyiEdWRwNoIjgg",
-		"enr:-LK4QPxe-mDiSOtEB_Y82ozvxn9aQM07Ui8A-vQHNgYGMMthfsfOabaaTHhhJHFCBQQVRjBww_A5bM1rf8MlkJU_l68Eh2F0dG5ldHOIAADAAAAAAACEZXRoMpBpt9l0BAFwAAABAAAAAAAAgmlkgnY0gmlwhLKAiOmJc2VjcDI1NmsxoQJu6T9pclPObAzEVQ53DpVQqjadmVxdTLL-J3h9NFoCeIN0Y3CCIyiDdWRwgiMo",
+		"enr:-KG4QCvyykb0pA1T-EZJUPkl2P1PKYk8-4El8TqwWdKwtoI6NtIBGMJVDgGZKVy2eMszI0_ermORtQ340lj1dTHzGVVPhGV0aDKQAZ4hrQYBcAD__________4JpZIJ2NIJpcIQ5gNI3iXNlY3AyNTZrMaEDMQYffETNbuGwVzWEJSgCpA50LTxHUWU1A0TDfleEa5mDdGNwgjvFg3VkcII7xQ",
-		"enr:-Ly4QGbOw4xNel5EhmDsJJ-QhC9XycWtsetnWoZ0uRy381GHdHsNHJiCwDTOkb3S1Ade0SFQkWJX_pgb3g8Jfh93rvMBh2F0dG5ldHOIAAAAAAAAAACEZXRoMpBpt9l0BAFwAAABAAAAAAAAgmlkgnY0gmlwhJK-DYCJc2VjcDI1NmsxoQOxKv9sv3zKF8GDewgFGGHKP5HCZZpPpTrwl9eXKAWGxIhzeW5jbmV0cwCDdGNwgiMog3VkcIIjKA",
-		// Teku
-		"enr:-LS4QG0uV4qvcpJ-HFDJRGBmnlD3TJo7yc4jwK8iP7iKaTlfQ5kZvIDspLMJhk7j9KapuL9yyHaZmwTEZqr10k9XumyCEcmHYXR0bmV0c4gAAAAABgAAAIRldGgykGm32XQEAXAAAAEAAAAAAACCaWSCdjSCaXCErK4j-YlzZWNwMjU2azGhAgfWRBEJlb7gAhXIB5ePmjj2b8io0UpEenq1Kl9cxStJg3RjcIIjKIN1ZHCCIyg",
-		// Sigma Prime
-		"enr:-Le4QLoE1wFHSlGcm48a9ZESb_MRLqPPu6G0vHqu4MaUcQNDHS69tsy-zkN0K6pglyzX8m24mkb-LtBcbjAYdP1uxm4BhGV0aDKQabfZdAQBcAAAAQAAAAAAAIJpZIJ2NIJpcIQ5gR6Wg2lwNpAgAUHQBwEQAAAAAAAAADR-iXNlY3AyNTZrMaEDPMSNdcL92uNIyCsS177Z6KTXlbZakQqxv3aQcWawNXeDdWRwgiMohHVkcDaCI4I",
 	}
 	OverrideBeaconNetworkConfig(cfg)
 }

encoding/bytesutil/hex.go

@@ -22,14 +22,10 @@ func IsHex(b []byte) bool {
 // DecodeHexWithLength takes a string and a length in bytes,
 // and validates whether the string is a hex and has the correct length.
 func DecodeHexWithLength(s string, length int) ([]byte, error) {
-	bytes, err := hexutil.Decode(s)
+	if len(s) != 2*length+2 {
-	if err != nil {
-		return nil, errors.Wrap(err, fmt.Sprintf("%s is not a valid hex", s))
-	}
-	if len(bytes) != length {
 		return nil, fmt.Errorf("%s is not length %d bytes", s, length)
 	}
-	return bytes, nil
+	return hexutil.Decode(s)
 }
 
 // DecodeHexWithMaxLength takes a string and a length in bytes,