Use finalized state for validator custody instead of head state. (#15243)

* `finalizedState` ==> `FinalizedState`.
We'll need it in an other package later.

* `setTargetValidatorsCustodyRequirement`: Use finalized state instead of head state.

* Fix James's comment.

.bazelrc

@@ -22,7 +22,6 @@ coverage --define=coverage_enabled=1
 build --workspace_status_command=./hack/workspace_status.sh
 
 build --define blst_disabled=false
-build --compilation_mode=opt
 run --define blst_disabled=false
 
 build:blst_disabled --define blst_disabled=true

CHANGELOG.md

@@ -4,6 +4,64 @@ All notable changes to this project will be documented in this file.
 
 The format is based on Keep a Changelog, and this project adheres to Semantic Versioning.
 
+## [v6.0.0](https://github.com/prysmaticlabs/prysm/compare/v5.3.2...v6.0.0) - 2025-04-21
+
+This release introduces Mainnet support for the upcoming Electra + Prague (Pectra) fork. The fork is scheduled for mainnet epoch 364032 (May 7, 2025, 10:05:11 UTC). You MUST update Prysm Beacon Node, Prysm Validator Client, and your execution layer client to the Pectra ready release prior to the fork to stay on the correct chain.
+
+Besides Pectra, we have more light client API support, cleanups, and a few bugfixes. Please review the changelog below and update your client as soon as practical before May 7.
+
+This release is **mandatory** for all operators before May 7.
+
+### Added
+
+- Implemented validator identities Beacon API endpoint. [[PR]](https://github.com/prysmaticlabs/prysm/pull/15086)
+- Add SSZ support to light client updates by range API. [[PR]](https://github.com/prysmaticlabs/prysm/pull/15082)
+- Add light client ssz types to the spec test. [[PR]](https://github.com/prysmaticlabs/prysm/pull/15097)
+- Added the ability for execution requests to be tested in e2e with electra. [[PR]](https://github.com/prysmaticlabs/prysm/pull/14971)
+- Add warning messages for gas limit ranges that might be problematic. Low gas limits (≤10% of default) may cause transactions to fail, while high gas limits (>150% of default) could lead to block propagation issues. [[PR]](https://github.com/prysmaticlabs/prysm/pull/15078)
+- Add light client store object to the beacon node object. [[PR]](https://github.com/prysmaticlabs/prysm/pull/15120)
+- prysmctl option in wrapper script to generate devnet ssz. [[PR]](https://github.com/prysmaticlabs/prysm/pull/15145)
+- Add support for Electra fork epoch. [[PR]](https://github.com/prysmaticlabs/prysm/pull/15132)
+
+### Changed
+
+- The validator client will no longer use the full list of committee values but instead use the committee length and validator committee index. [[PR]](https://github.com/prysmaticlabs/prysm/pull/15039)
+- Remove the header `Content-Disposition` from the `httputil.WriteSSZ` function. No `filename` parameter is needed anymore. [[PR]](https://github.com/prysmaticlabs/prysm/pull/15092)
+- Sort attestations in proposer block by reward. [[PR]](https://github.com/prysmaticlabs/prysm/pull/15093)
+- More efficient query method for stategen to retrieve blocks between a given state and the replay target block. This avoids attempting to look up blocks that are not needed for head replay queries, which may be missing due to a previous rollback bug. [[PR]](https://github.com/prysmaticlabs/prysm/pull/15063)
+- removed old web3signer metrics in favor for a universal one. [[PR]](https://github.com/prysmaticlabs/prysm/pull/14920)
+- Deprecated everything related with the gRPC API. [[PR]](https://github.com/prysmaticlabs/prysm/pull/14944)
+- Migrate Prysm repo to Offchain Labs organization ahead of Pectra upgrade v6. [[PR]](https://github.com/prysmaticlabs/prysm/pull/15140)
+
+### Deprecated
+
+- deprecates and removes usage of the `--trace` flag and`--cpuprofile` flag in favor of just using `--pprof`. [[PR]](https://github.com/prysmaticlabs/prysm/pull/15083)
+
+### Removed
+
+- Remove /eth/v1/beacon/states/head/committees call when getting duties. [[PR]](https://github.com/prysmaticlabs/prysm/pull/15039)
+- Removed unused hack scripts. [[PR]](https://github.com/prysmaticlabs/prysm/pull/15157)
+- Remove `disable-committee-aware-packing` flag. [[PR]](https://github.com/prysmaticlabs/prysm/pull/15162)
+- Remove deprecated flags for the major release. [[PR]](https://github.com/prysmaticlabs/prysm/pull/15165)
+- Removed Beacon API endpoints which have been deprecated at the Deneb fork. [[PR]](https://github.com/prysmaticlabs/prysm/pull/15166)
+
+### Fixed
+
+- The `--rpc` flag will now properly enable the keymanager APIs without web. The `--web` will enable both validator api endpoints and web. [[PR]](https://github.com/prysmaticlabs/prysm/pull/15080)
+- Use latest state to pack attestation. [[PR]](https://github.com/prysmaticlabs/prysm/pull/15113)
+- Clean up dangling block index entries for blocks that were previously deleted by incomplete cleanup code. [[PR]](https://github.com/prysmaticlabs/prysm/pull/15040)
+- Fixed to use io stream instead of stream read. [[PR]](https://github.com/prysmaticlabs/prysm/pull/15089)
+- When using a DV, send all aggregations for a slot and committee. [[PR]](https://github.com/prysmaticlabs/prysm/pull/15110)
+- Fixed a bug in consolidation request processing. [[PR]](https://github.com/prysmaticlabs/prysm/pull/15122)
+- Fix State Getter for pending withdrawal balance. [[PR]](https://github.com/prysmaticlabs/prysm/pull/15123)
+- Fixed a bug in checking for attestation lengths in our block. [[PR]](https://github.com/prysmaticlabs/prysm/pull/15134)
+- Fix Committee Index Check For Aggregates. [[PR]](https://github.com/prysmaticlabs/prysm/pull/15146)
+- Fix filtering by committee index post-Electra in `ListAttestationsV2`. [[PR]](https://github.com/prysmaticlabs/prysm/pull/15148)
+- Peers giving invalid data in range syncing are now downscored. [[PR]](https://github.com/prysmaticlabs/prysm/pull/15149)
+- Adding fork guard to attestation api endpoints so that it doesn't accidentally include wrong attestation types in the pool. [[PR]](https://github.com/prysmaticlabs/prysm/pull/15161)
+- fixed underflow with balances in leaking edge case with expected withdrawals. [[PR]](https://github.com/prysmaticlabs/prysm/pull/15191)
+- Attribute block and blob issues to correct peers during range syncing. [[PR]](https://github.com/prysmaticlabs/prysm/pull/15173)
+
 ## [v5.3.2](https://github.com/prysmaticlabs/prysm/compare/v5.3.1...v5.3.2) - 2025-03-25
 
 This release introduces support for the `Hoodi` testnet.
@@ -3255,4 +3313,4 @@ There are no security updates in this release.
 
 # Older than v2.0.0
 
-For changelog history for releases older than v2.0.0, please refer to https://github.com/prysmaticlabs/prysm/releases
+For changelog history for releases older than v2.0.0, please refer to https://github.com/prysmaticlabs/prysm/releases

api/server/structs/endpoints_beacon.go

@@ -263,6 +263,13 @@ type ChainHead struct {
 	OptimisticStatus           bool   `json:"optimistic_status"`
 }
 
+type GetPendingConsolidationsResponse struct {
+	Version             string                  `json:"version"`
+	ExecutionOptimistic bool                    `json:"execution_optimistic"`
+	Finalized           bool                    `json:"finalized"`
+	Data                []*PendingConsolidation `json:"data"`
+}
+
 type GetPendingDepositsResponse struct {
 	Version             string            `json:"version"`
 	ExecutionOptimistic bool              `json:"execution_optimistic"`

beacon-chain/blockchain/execution_engine.go

@@ -184,13 +184,17 @@ func (s *Service) notifyForkchoiceUpdate(ctx context.Context, arg *fcuConfig) (*
 	return payloadID, nil
 }
 
-func firePayloadAttributesEvent(_ context.Context, f event.SubscriberSender, nextSlot primitives.Slot) {
+func (s *Service) firePayloadAttributesEvent(f event.SubscriberSender, block interfaces.ReadOnlySignedBeaconBlock, root [32]byte, nextSlot primitives.Slot) {
+	// If we're syncing a block in the past and init-sync is still running, we shouldn't fire this event.
+	if !s.cfg.SyncChecker.Synced() {
+		return
+	}
 	// the fcu args have differing amounts of completeness based on the code path,
 	// and there is work we only want to do if a client is actually listening to the events beacon api endpoint.
 	// temporary solution: just fire a blank event and fill in the details in the api handler.
 	f.Send(&feed.Event{
 		Type: statefeed.PayloadAttributes,
-		Data: payloadattribute.EventData{ProposalSlot: nextSlot},
+		Data: payloadattribute.EventData{HeadBlock: block, HeadRoot: root, ProposalSlot: nextSlot},
 	})
 }
 

beacon-chain/blockchain/forkchoice_update_execution.go

@@ -102,7 +102,7 @@ func (s *Service) forkchoiceUpdateWithExecution(ctx context.Context, args *fcuCo
 		log.WithError(err).Error("could not save head")
 	}
 
-	go firePayloadAttributesEvent(ctx, s.cfg.StateNotifier.StateFeed(), s.CurrentSlot()+1)
+	go s.firePayloadAttributesEvent(s.cfg.StateNotifier.StateFeed(), args.headBlock, args.headRoot, s.CurrentSlot()+1)
 
 	// Only need to prune attestations from pool if the head has changed.
 	s.pruneAttsFromPool(s.ctx, args.headState, args.headBlock)

beacon-chain/blockchain/kzg/BUILD.bazel

@@ -7,7 +7,7 @@ go_library(
         "trusted_setup.go",
         "validation.go",
     ],
-    embedsrcs = ["trusted_setup.json"],
+    embedsrcs = ["trusted_setup_4096.json"],
     importpath = "github.com/OffchainLabs/prysm/v6/beacon-chain/blockchain/kzg",
     visibility = ["//visibility:public"],
     deps = [

beacon-chain/blockchain/kzg/kzg.go

@@ -31,25 +31,31 @@ type Bytes48 = ckzg4844.Bytes48
 // Bytes32 is a 32-byte array.
 type Bytes32 = ckzg4844.Bytes32
 
-// CellsAndProofs represents the Cells and Proofs corresponding to
-// a single blob.
+// CellsAndProofs represents the Cells and Proofs corresponding to a single blob.
 type CellsAndProofs struct {
 	Cells  []Cell
 	Proofs []Proof
 }
 
+// BlobToKZGCommitment computes a KZG commitment from a given blob.
 func BlobToKZGCommitment(blob *Blob) (Commitment, error) {
-	kzgBlob := kzg4844.Blob(*blob)
-	comm, err := kzg4844.BlobToCommitment(&kzgBlob)
+	var kzgBlob kzg4844.Blob
+	copy(kzgBlob[:], blob[:])
+
+	commitment, err := kzg4844.BlobToCommitment(&kzgBlob)
 	if err != nil {
 		return Commitment{}, err
 	}
-	return Commitment(comm), nil
+
+	return Commitment(commitment), nil
 }
 
+// ComputeCells computes the (extended) cells from a given blob.
 func ComputeCells(blob *Blob) ([]Cell, error) {
-	ckzgBlob := (*ckzg4844.Blob)(blob)
-	ckzgCells, err := ckzg4844.ComputeCells(ckzgBlob)
+	var ckzgBlob ckzg4844.Blob
+	copy(ckzgBlob[:], blob[:])
+
+	ckzgCells, err := ckzg4844.ComputeCells(&ckzgBlob)
 	if err != nil {
 		return nil, errors.Wrap(err, "compute cells")
 	}
@@ -58,11 +64,15 @@ func ComputeCells(blob *Blob) ([]Cell, error) {
 	for i := range ckzgCells {
 		cells[i] = Cell(ckzgCells[i])
 	}
+
 	return cells, nil
 }
 
+// ComputeBlobKZGProof computes the blob KZG proof from a given blob and its commitment.
 func ComputeBlobKZGProof(blob *Blob, commitment Commitment) (Proof, error) {
-	kzgBlob := kzg4844.Blob(*blob)
+	var kzgBlob kzg4844.Blob
+	copy(kzgBlob[:], blob[:])
+
 	proof, err := kzg4844.ComputeBlobProof(&kzgBlob, kzg4844.Commitment(commitment))
 	if err != nil {
 		return [48]byte{}, err
@@ -70,9 +80,12 @@ func ComputeBlobKZGProof(blob *Blob, commitment Commitment) (Proof, error) {
 	return Proof(proof), nil
 }
 
+// ComputeCellsAndKZGProofs computes the cells and cells KZG proofs from a given blob.
 func ComputeCellsAndKZGProofs(blob *Blob) (CellsAndProofs, error) {
-	ckzgBlob := (*ckzg4844.Blob)(blob)
-	ckzgCells, ckzgProofs, err := ckzg4844.ComputeCellsAndKZGProofs(ckzgBlob)
+	var ckzgBlob ckzg4844.Blob
+	copy(ckzgBlob[:], blob[:])
+
+	ckzgCells, ckzgProofs, err := ckzg4844.ComputeCellsAndKZGProofs(&ckzgBlob)
 	if err != nil {
 		return CellsAndProofs{}, err
 	}
@@ -80,9 +93,12 @@ func ComputeCellsAndKZGProofs(blob *Blob) (CellsAndProofs, error) {
 	return makeCellsAndProofs(ckzgCells[:], ckzgProofs[:])
 }
 
+// VerifyCellKZGProofBatch verifies the KZG proofs for a given slice of commitments, cells indices, cells and proofs.
+// Note: It is way more efficient to call once this function with big slices than calling it multiple times with small slices.
 func VerifyCellKZGProofBatch(commitmentsBytes []Bytes48, cellIndices []uint64, cells []Cell, proofsBytes []Bytes48) (bool, error) {
 	// Convert `Cell` type to `ckzg4844.Cell`
 	ckzgCells := make([]ckzg4844.Cell, len(cells))
+
 	for i := range cells {
 		ckzgCells[i] = ckzg4844.Cell(cells[i])
 	}
@@ -90,6 +106,7 @@ func VerifyCellKZGProofBatch(commitmentsBytes []Bytes48, cellIndices []uint64, c
 	return ckzg4844.VerifyCellKZGProofBatch(commitmentsBytes, cellIndices, ckzgCells, proofsBytes)
 }
 
+// RecoverCellsAndKZGProofs recovers the complete cells and KZG proofs from a given set of cell indices and partial cells.
 func RecoverCellsAndKZGProofs(cellIndices []uint64, partialCells []Cell) (CellsAndProofs, error) {
 	// Convert `Cell` type to `ckzg4844.Cell`
 	ckzgPartialCells := make([]ckzg4844.Cell, len(partialCells))
@@ -105,14 +122,15 @@ func RecoverCellsAndKZGProofs(cellIndices []uint64, partialCells []Cell) (CellsA
 	return makeCellsAndProofs(ckzgCells[:], ckzgProofs[:])
 }
 
-// Convert cells/proofs to the CellsAndProofs type defined in this package.
+// makeCellsAndProofs converts cells/proofs to the CellsAndProofs type defined in this package.
 func makeCellsAndProofs(ckzgCells []ckzg4844.Cell, ckzgProofs []ckzg4844.KZGProof) (CellsAndProofs, error) {
 	if len(ckzgCells) != len(ckzgProofs) {
 		return CellsAndProofs{}, errors.New("different number of cells/proofs")
 	}
 
-	var cells []Cell
-	var proofs []Proof
+	cells := make([]Cell, 0, len(ckzgCells))
+	proofs := make([]Proof, 0, len(ckzgProofs))
+
 	for i := range ckzgCells {
 		cells = append(cells, Cell(ckzgCells[i]))
 		proofs = append(proofs, Proof(ckzgProofs[i]))

beacon-chain/blockchain/kzg/trusted_setup.go

@@ -11,7 +11,8 @@ import (
 )
 
 var (
-	//go:embed trusted_setup.json
+	// https://github.com/ethereum/consensus-specs/blob/dev/presets/mainnet/trusted_setups/trusted_setup_4096.json
+	//go:embed trusted_setup_4096.json
 	embeddedTrustedSetup []byte // 1.2Mb
 	kzgContext           *GoKZG.Context
 	kzgLoaded            bool
@@ -29,9 +30,11 @@ func Start() error {
 	if err != nil {
 		return errors.Wrap(err, "could not parse trusted setup JSON")
 	}
+
 	kzgContext, err = GoKZG.NewContext4096(&GoKZG.JSONTrustedSetup{
 		SetupG2:         trustedSetup.G2Monomial[:],
-		SetupG1Lagrange: trustedSetup.G1Lagrange})
+		SetupG1Lagrange: trustedSetup.G1Lagrange,
+	})
 	if err != nil {
 		return errors.Wrap(err, "could not initialize go-kzg context")
 	}
@@ -41,26 +44,30 @@ func Start() error {
 	for i, g1 := range &trustedSetup.G1Monomial {
 		copy(g1MonomialBytes[i*(len(g1)-2)/2:], hexutil.MustDecode(g1))
 	}
+
 	// Length of a G1 point, converted from hex to binary.
 	g1LagrangeBytes := make([]byte, len(trustedSetup.G1Lagrange)*(len(trustedSetup.G1Lagrange[0])-2)/2)
 	for i, g1 := range &trustedSetup.G1Lagrange {
 		copy(g1LagrangeBytes[i*(len(g1)-2)/2:], hexutil.MustDecode(g1))
 	}
+
 	// Length of a G2 point, converted from hex to binary.
 	g2MonomialBytes := make([]byte, len(trustedSetup.G2Monomial)*(len(trustedSetup.G2Monomial[0])-2)/2)
 	for i, g2 := range &trustedSetup.G2Monomial {
 		copy(g2MonomialBytes[i*(len(g2)-2)/2:], hexutil.MustDecode(g2))
 	}
-	if !kzgLoaded {
-		// TODO: Provide a configuration option for this.
-		var precompute uint = 8
 
-		// Free the current trusted setup before running this method. CKZG
-		// panics if the same setup is run multiple times.
+	if !kzgLoaded {
+		const precompute uint = 8
+
+		kzgLoaded = true
+
+		// Free the current trusted setup before running this method.
+		// CKZG panics if the same setup is run multiple times.
 		if err = CKZG.LoadTrustedSetup(g1MonomialBytes, g1LagrangeBytes, g2MonomialBytes, precompute); err != nil {
 			return errors.Wrap(err, "load trust setup")
 		}
 	}
-	kzgLoaded = true
+
 	return nil
 }

beacon-chain/blockchain/mock_test.go

@@ -20,6 +20,7 @@ func testServiceOptsWithDB(t *testing.T) []Option {
 		WithForkChoiceStore(fcs),
 		WithClockSynchronizer(cs),
 		WithStateNotifier(&mock.MockStateNotifier{RecordEvents: true}),
+		WithSyncChecker(&mock.MockSyncChecker{}),
 	}
 }
 

beacon-chain/blockchain/process_block.go

@@ -924,9 +924,13 @@ func (s *Service) lateBlockTasks(ctx context.Context) {
 	attribute := s.getPayloadAttribute(ctx, headState, s.CurrentSlot()+1, headRoot[:])
 	// return early if we are not proposing next slot
 	if attribute.IsEmpty() {
+		headBlock, err := s.headBlock()
+		if err != nil {
+			log.WithError(err).WithField("head_root", headRoot).Error("unable to retrieve head block to fire payload attributes event")
+		}
 		// notifyForkchoiceUpdate fires the payload attribute event. But in this case, we won't
 		// call notifyForkchoiceUpdate, so the event is fired here.
-		go firePayloadAttributesEvent(ctx, s.cfg.StateNotifier.StateFeed(), s.CurrentSlot()+1)
+		go s.firePayloadAttributesEvent(s.cfg.StateNotifier.StateFeed(), headBlock, headRoot, s.CurrentSlot()+1)
 		return
 	}
 

beacon-chain/blockchain/process_block_helpers.go

@@ -103,15 +103,29 @@ func (s *Service) sendStateFeedOnBlock(cfg *postBlockProcessConfig) {
 		log.WithError(err).Debug("Could not check if block is optimistic")
 		optimistic = true
 	}
+	currEpoch := slots.ToEpoch(s.CurrentSlot())
+	currDependenRoot, err := s.cfg.ForkChoiceStore.DependentRoot(currEpoch)
+	if err != nil {
+		log.WithError(err).Debug("Could not get dependent root")
+	}
+	prevDependentRoot := [32]byte{}
+	if currEpoch > 0 {
+		prevDependentRoot, err = s.cfg.ForkChoiceStore.DependentRoot(currEpoch - 1)
+		if err != nil {
+			log.WithError(err).Debug("Could not get previous dependent root")
+		}
+	}
 	// Send notification of the processed block to the state feed.
 	s.cfg.StateNotifier.StateFeed().Send(&feed.Event{
 		Type: statefeed.BlockProcessed,
 		Data: &statefeed.BlockProcessedData{
-			Slot:        cfg.roblock.Block().Slot(),
-			BlockRoot:   cfg.roblock.Root(),
-			SignedBlock: cfg.roblock,
-			Verified:    true,
-			Optimistic:  optimistic,
+			Slot:              cfg.roblock.Block().Slot(),
+			BlockRoot:         cfg.roblock.Root(),
+			SignedBlock:       cfg.roblock,
+			CurrDependentRoot: currDependenRoot,
+			PrevDependentRoot: prevDependentRoot,
+			Verified:          true,
+			Optimistic:        optimistic,
 		},
 	})
 }

beacon-chain/blockchain/testing/mock.go

@@ -53,6 +53,7 @@ type ChainService struct {
 	InitSyncBlockRoots          map[[32]byte]bool
 	DB                          db.Database
 	State                       state.BeaconState
+	HeadStateErr                error
 	Block                       interfaces.ReadOnlySignedBeaconBlock
 	VerifyBlkDescendantErr      error
 	stateNotifier               statefeed.Notifier
@@ -365,6 +366,9 @@ func (s *ChainService) HeadState(context.Context) (state.BeaconState, error) {
 
 // HeadStateReadOnly mocks HeadStateReadOnly method in chain service.
 func (s *ChainService) HeadStateReadOnly(context.Context) (state.ReadOnlyBeaconState, error) {
+	if s.HeadStateErr != nil {
+		return nil, s.HeadStateErr
+	}
 	return s.State, nil
 }
 
@@ -727,3 +731,14 @@ func (*ChainService) ReceiveDataColumns(_ []blocks.VerifiedRODataColumn) error {
 func (c *ChainService) TargetRootForEpoch(_ [32]byte, _ primitives.Epoch) ([32]byte, error) {
 	return c.TargetRoot, nil
 }
+
+// MockSyncChecker is a mock implementation of blockchain.Checker.
+// We can't make an assertion here that this is true because that would create a circular dependency.
+type MockSyncChecker struct {
+	synced bool
+}
+
+// Synced satisfies the blockchain.Checker interface.
+func (m *MockSyncChecker) Synced() bool {
+	return m.synced
+}

beacon-chain/core/blocks/proposer_slashing.go

@@ -16,6 +16,9 @@ import (
 	"google.golang.org/protobuf/proto"
 )
 
+// ErrCouldNotVerifyBlockHeader is returned when a block header's signature cannot be verified.
+var ErrCouldNotVerifyBlockHeader = errors.New("could not verify beacon block header")
+
 type slashValidatorFunc func(
 	ctx context.Context,
 	st state.BeaconState,
@@ -114,7 +117,7 @@ func VerifyProposerSlashing(
 	for _, header := range headers {
 		if err := signing.ComputeDomainVerifySigningRoot(beaconState, pIdx, slots.ToEpoch(hSlot),
 			header.Header, params.BeaconConfig().DomainBeaconProposer, header.Signature); err != nil {
-			return errors.Wrap(err, "could not verify beacon block header")
+			return errors.Wrap(ErrCouldNotVerifyBlockHeader, err.Error())
 		}
 	}
 	return nil

beacon-chain/core/feed/block/events.go

@@ -11,6 +11,8 @@ const (
 
 // ReceivedBlockData is the data sent with ReceivedBlock events.
 type ReceivedBlockData struct {
-	SignedBlock  interfaces.ReadOnlySignedBeaconBlock
-	IsOptimistic bool
+	SignedBlock       interfaces.ReadOnlySignedBeaconBlock
+	CurrDependentRoot [32]byte
+	PrevDependentRoot [32]byte
+	IsOptimistic      bool
 }

beacon-chain/core/feed/state/events.go

@@ -43,6 +43,10 @@ type BlockProcessedData struct {
 	BlockRoot [32]byte
 	// SignedBlock is the physical processed block.
 	SignedBlock interfaces.ReadOnlySignedBeaconBlock
+	// CurrDependentRoot is the current dependent root
+	CurrDependentRoot [32]byte
+	// PrevDependentRoot is the previous dependent root
+	PrevDependentRoot [32]byte
 	// Verified is true if the block's BLS contents have been verified.
 	Verified bool
 	// Optimistic is true if the block is optimistic.

beacon-chain/core/fulu/upgrade.go

@@ -11,7 +11,7 @@ import (
 )
 
 // UpgradeToFulu updates inputs a generic state to return the version Fulu state.
-// https://github.com/ethereum/consensus-specs/blob/dev/specs/fulu/fork.md#upgrading-the-state
+// https://github.com/ethereum/consensus-specs/blob/v1.5.0-beta.5/specs/fulu/fork.md#upgrading-the-state
 func UpgradeToFulu(beaconState state.BeaconState) (state.BeaconState, error) {
 	currentSyncCommittee, err := beaconState.CurrentSyncCommittee()
 	if err != nil {
@@ -69,7 +69,7 @@ func UpgradeToFulu(beaconState state.BeaconState) (state.BeaconState, error) {
 	if err != nil {
 		return nil, err
 	}
-	depostiRequestsStartIndex, err := beaconState.DepositRequestsStartIndex()
+	depositRequestsStartIndex, err := beaconState.DepositRequestsStartIndex()
 	if err != nil {
 		return nil, err
 	}
@@ -158,7 +158,7 @@ func UpgradeToFulu(beaconState state.BeaconState) (state.BeaconState, error) {
 		NextWithdrawalValidatorIndex: vi,
 		HistoricalSummaries:          summaries,
 
-		DepositRequestsStartIndex:     depostiRequestsStartIndex,
+		DepositRequestsStartIndex:     depositRequestsStartIndex,
 		DepositBalanceToConsume:       depositBalanceToConsume,
 		ExitBalanceToConsume:          exitBalanceToConsume,
 		EarliestExitEpoch:             earliestExitEpoch,

beacon-chain/core/peerdas/BUILD.bazel

@@ -10,6 +10,7 @@ go_library(
         "peer_sampling.go",
         "reconstruction.go",
         "util.go",
+        "validator.go",
     ],
     importpath = "github.com/OffchainLabs/prysm/v6/beacon-chain/core/peerdas",
     visibility = ["//visibility:public"],
@@ -47,6 +48,7 @@ go_test(
         "peer_sampling_test.go",
         "reconstruction_test.go",
         "utils_test.go",
+        "validator_test.go",
     ],
     deps = [
         ":go_default_library",

beacon-chain/core/peerdas/das_core.go

@@ -7,12 +7,10 @@ import (
 	"time"
 
 	"github.com/OffchainLabs/prysm/v6/beacon-chain/blockchain/kzg"
-	beaconState "github.com/OffchainLabs/prysm/v6/beacon-chain/state"
 	fieldparams "github.com/OffchainLabs/prysm/v6/config/fieldparams"
 	"github.com/OffchainLabs/prysm/v6/config/params"
 	"github.com/OffchainLabs/prysm/v6/consensus-types/blocks"
 	"github.com/OffchainLabs/prysm/v6/consensus-types/interfaces"
-	"github.com/OffchainLabs/prysm/v6/consensus-types/primitives"
 	"github.com/OffchainLabs/prysm/v6/crypto/hash"
 	"github.com/OffchainLabs/prysm/v6/encoding/bytesutil"
 	ethpb "github.com/OffchainLabs/prysm/v6/proto/prysm/v1alpha1"
@@ -23,6 +21,7 @@ import (
 
 var (
 	// Custom errors
+	ErrCustodyGroupTooLarge           = errors.New("custody group too large")
 	errCustodyGroupCountTooLarge      = errors.New("custody group count too large")
 	errWrongComputedCustodyGroupCount = errors.New("wrong computed custody group count, should never happen")
 
@@ -38,7 +37,7 @@ const (
 )
 
 // CustodyGroups computes the custody groups the node should participate in for custody.
-// https://github.com/ethereum/consensus-specs/blob/v1.5.0-alpha.10/specs/fulu/das-core.md#get_custody_groups
+// https://github.com/ethereum/consensus-specs/blob/v1.5.0-beta.5/specs/fulu/das-core.md#get_custody_groups
 func CustodyGroups(nodeId enode.ID, custodyGroupCount uint64) (map[uint64]bool, error) {
 	numberOfCustodyGroup := params.BeaconConfig().NumberOfCustodyGroups
 
@@ -81,7 +80,7 @@ func CustodyGroups(nodeId enode.ID, custodyGroupCount uint64) (map[uint64]bool,
 }
 
 // ComputeColumnsForCustodyGroup computes the columns for a given custody group.
-// https://github.com/ethereum/consensus-specs/blob/v1.5.0-alpha.10/specs/fulu/das-core.md#compute_columns_for_custody_group
+// https://github.com/ethereum/consensus-specs/blob/v1.5.0-beta.5/specs/fulu/das-core.md#compute_columns_for_custody_group
 func ComputeColumnsForCustodyGroup(custodyGroup uint64) ([]uint64, error) {
 	beaconConfig := params.BeaconConfig()
 	numberOfCustodyGroup := beaconConfig.NumberOfCustodyGroups
@@ -176,67 +175,6 @@ func DataColumnSidecars(signedBlock interfaces.ReadOnlySignedBeaconBlock, cellsA
 	return sidecars, nil
 }
 
-// CustodyGroupSamplingSize returns the number of custody groups the node should sample from.
-// https://github.com/ethereum/consensus-specs/blob/v1.5.0-alpha.10/specs/fulu/das-core.md#custody-sampling
-func (custodyInfo *CustodyInfo) CustodyGroupSamplingSize(ct CustodyType) uint64 {
-	custodyGroupCount := custodyInfo.TargetGroupCount.Get()
-
-	if ct == Actual {
-		custodyGroupCount = custodyInfo.ActualGroupCount()
-	}
-
-	samplesPerSlot := params.BeaconConfig().SamplesPerSlot
-	return max(samplesPerSlot, custodyGroupCount)
-}
-
-// CustodyColumns computes the custody columns from the custody groups.
-func CustodyColumns(custodyGroups map[uint64]bool) (map[uint64]bool, error) {
-	numberOfCustodyGroups := params.BeaconConfig().NumberOfCustodyGroups
-
-	custodyGroupCount := len(custodyGroups)
-
-	// Compute the columns for each custody group.
-	columns := make(map[uint64]bool, custodyGroupCount)
-	for group := range custodyGroups {
-		if group >= numberOfCustodyGroups {
-			return nil, errCustodyGroupCountTooLarge
-		}
-
-		groupColumns, err := ComputeColumnsForCustodyGroup(group)
-		if err != nil {
-			return nil, errors.Wrap(err, "compute columns for custody group")
-		}
-
-		for _, column := range groupColumns {
-			columns[column] = true
-		}
-	}
-
-	return columns, nil
-}
-
-// ValidatorsCustodyRequirement returns the number of custody groups regarding the validator indices attached to the beacon node.
-// https://github.com/ethereum/consensus-specs/blob/dev/specs/fulu/das-core.md#validator-custody
-func ValidatorsCustodyRequirement(state beaconState.ReadOnlyBeaconState, validatorsIndex map[primitives.ValidatorIndex]bool) (uint64, error) {
-	totalNodeBalance := uint64(0)
-	for index := range validatorsIndex {
-		balance, err := state.BalanceAtIndex(index)
-		if err != nil {
-			return 0, errors.Wrapf(err, "balance at index for validator index %v", index)
-		}
-
-		totalNodeBalance += balance
-	}
-
-	beaconConfig := params.BeaconConfig()
-	numberOfCustodyGroup := beaconConfig.NumberOfCustodyGroups
-	validatorCustodyRequirement := beaconConfig.ValidatorCustodyRequirement
-	balancePerAdditionalCustodyGroup := beaconConfig.BalancePerAdditionalCustodyGroup
-
-	count := totalNodeBalance / balancePerAdditionalCustodyGroup
-	return min(max(count, validatorCustodyRequirement), numberOfCustodyGroup), nil
-}
-
 // Blobs extract blobs from `dataColumnsSidecar`.
 // This can be seen as the reciprocal function of DataColumnSidecars.
 // `dataColumnsSidecar` needs to contain the datacolumns corresponding to the non-extended matrix,
@@ -344,6 +282,45 @@ func Blobs(indices map[uint64]bool, dataColumnsSidecar []*ethpb.DataColumnSideca
 	return verifiedROBlobs, nil
 }
 
+// CustodyGroupSamplingSize returns the number of custody groups the node should sample from.
+// https://github.com/ethereum/consensus-specs/blob/v1.5.0-beta.5/specs/fulu/das-core.md#custody-sampling
+func (custodyInfo *CustodyInfo) CustodyGroupSamplingSize(ct CustodyType) uint64 {
+	custodyGroupCount := custodyInfo.TargetGroupCount.Get()
+
+	if ct == Actual {
+		custodyGroupCount = custodyInfo.ActualGroupCount()
+	}
+
+	samplesPerSlot := params.BeaconConfig().SamplesPerSlot
+	return max(samplesPerSlot, custodyGroupCount)
+}
+
+// CustodyColumns computes the custody columns from the custody groups.
+func CustodyColumns(custodyGroups map[uint64]bool) (map[uint64]bool, error) {
+	numberOfCustodyGroups := params.BeaconConfig().NumberOfCustodyGroups
+
+	custodyGroupCount := len(custodyGroups)
+
+	// Compute the columns for each custody group.
+	columns := make(map[uint64]bool, custodyGroupCount)
+	for group := range custodyGroups {
+		if group >= numberOfCustodyGroups {
+			return nil, ErrCustodyGroupTooLarge
+		}
+
+		groupColumns, err := ComputeColumnsForCustodyGroup(group)
+		if err != nil {
+			return nil, errors.Wrap(err, "compute columns for custody group")
+		}
+
+		for _, column := range groupColumns {
+			columns[column] = true
+		}
+	}
+
+	return columns, nil
+}
+
 // populateAndFilterIndices returns a sorted slices of indices, setting all indices if none are provided,
 // and filtering out indices higher than the blob count.
 func populateAndFilterIndices(indices map[uint64]bool, blobCount uint64) []uint64 {

beacon-chain/core/peerdas/das_core_test.go

@@ -5,16 +5,19 @@ import (
 
 	"github.com/OffchainLabs/prysm/v6/beacon-chain/blockchain/kzg"
 	"github.com/OffchainLabs/prysm/v6/beacon-chain/core/peerdas"
-	state_native "github.com/OffchainLabs/prysm/v6/beacon-chain/state/state-native"
 	fieldparams "github.com/OffchainLabs/prysm/v6/config/fieldparams"
 	"github.com/OffchainLabs/prysm/v6/consensus-types/blocks"
-	"github.com/OffchainLabs/prysm/v6/consensus-types/primitives"
 	ethpb "github.com/OffchainLabs/prysm/v6/proto/prysm/v1alpha1"
 	"github.com/OffchainLabs/prysm/v6/testing/require"
 	"github.com/OffchainLabs/prysm/v6/testing/util"
 	"github.com/pkg/errors"
 )
 
+// ---------------------------------------------------------------
+// ( CustodyGroups is unit tested in spec tests.                 )
+// ( ComputeColumnsForCustodyGroup is unit tested in spec tests. )
+// ---------------------------------------------------------------
+
 func TestDataColumnSidecars(t *testing.T) {
 	var expected []*ethpb.DataColumnSidecar = nil
 	actual, err := peerdas.DataColumnSidecars(nil, []kzg.CellsAndProofs{})
@@ -151,46 +154,6 @@ func TestDataColumnsSidecarsBlobsRoundtrip(t *testing.T) {
 	require.DeepSSZEqual(t, verifiedROBlobs, roundtripBlobs)
 }
 
-func TestValidatorsCustodyRequirement(t *testing.T) {
-	testCases := []struct {
-		name     string
-		count    uint64
-		expected uint64
-	}{
-		{name: "0 validators", count: 0, expected: 8},
-		{name: "1 validator", count: 1, expected: 8},
-		{name: "8 validators", count: 8, expected: 8},
-		{name: "9 validators", count: 9, expected: 9},
-		{name: "100 validators", count: 100, expected: 100},
-		{name: "128 validators", count: 128, expected: 128},
-		{name: "129 validators", count: 129, expected: 128},
-		{name: "1000 validators", count: 1000, expected: 128},
-	}
-
-	const balance = uint64(32_000_000_000)
-
-	for _, tc := range testCases {
-		t.Run(tc.name, func(t *testing.T) {
-			balances := make([]uint64, 0, tc.count)
-			for range tc.count {
-				balances = append(balances, balance)
-			}
-
-			validatorsIndex := make(map[primitives.ValidatorIndex]bool)
-			for i := range tc.count {
-				validatorsIndex[primitives.ValidatorIndex(i)] = true
-			}
-
-			beaconState, err := state_native.InitializeFromProtoFulu(&ethpb.BeaconStateElectra{Balances: balances})
-			require.NoError(t, err)
-
-			actual, err := peerdas.ValidatorsCustodyRequirement(beaconState, validatorsIndex)
-			require.NoError(t, err)
-			require.Equal(t, tc.expected, actual)
-		})
-	}
-}
-
 func TestCustodyGroupSamplingSize(t *testing.T) {
 	testCases := []struct {
 		name                         string
@@ -246,3 +209,22 @@ func TestCustodyGroupSamplingSize(t *testing.T) {
 		})
 	}
 }
+
+func TestCustodyColumns(t *testing.T) {
+	t.Run("group too large", func(t *testing.T) {
+		_, err := peerdas.CustodyColumns(map[uint64]bool{1_000_000: true})
+		require.ErrorIs(t, err, peerdas.ErrCustodyGroupTooLarge)
+	})
+
+	t.Run("nominal", func(t *testing.T) {
+		input := map[uint64]bool{1: true, 2: true}
+		expected := map[uint64]bool{1: true, 2: true}
+
+		actual, err := peerdas.CustodyColumns(input)
+		require.NoError(t, err)
+		require.Equal(t, len(expected), len(actual))
+		for i := range actual {
+			require.Equal(t, expected[i], actual[i])
+		}
+	})
+}

beacon-chain/core/peerdas/info.go

@@ -103,6 +103,61 @@ func Info(nodeID enode.ID, custodyGroupCount uint64) (*info, bool, error) {
 	return result, false, nil
 }
 
+// ActualGroupCount returns the actual custody group count.
+func (custodyInfo *CustodyInfo) ActualGroupCount() uint64 {
+	return min(custodyInfo.TargetGroupCount.Get(), custodyInfo.ToAdvertiseGroupCount.Get())
+}
+
+// CustodyGroupCount returns the number of groups we should participate in for custody.
+func (tcgc *targetCustodyGroupCount) Get() uint64 {
+	// If subscribed to all subnets, return the number of custody groups.
+	if flags.Get().SubscribeAllDataSubnetsubnets {
+		return params.BeaconConfig().NumberOfCustodyGroups
+	}
+
+	tcgc.mut.RLock()
+	defer tcgc.mut.RUnlock()
+
+	// If no validators are tracked, return the default custody requirement.
+	if tcgc.validatorsCustodyRequirement == 0 {
+		return params.BeaconConfig().CustodyRequirement
+	}
+
+	// Return the validators custody requirement.
+	return tcgc.validatorsCustodyRequirement
+}
+
+// setValidatorsCustodyRequirement sets the validators custody requirement.
+func (tcgc *targetCustodyGroupCount) SetValidatorsCustodyRequirement(value uint64) {
+	tcgc.mut.Lock()
+	defer tcgc.mut.Unlock()
+
+	tcgc.validatorsCustodyRequirement = value
+}
+
+// Get returns the to advertise custody group count.
+func (tacgc *toAdverstiseCustodyGroupCount) Get() uint64 {
+	// If subscribed to all subnets, return the number of custody groups.
+	if flags.Get().SubscribeAllDataSubnetsubnets {
+		return params.BeaconConfig().NumberOfCustodyGroups
+	}
+
+	custodyRequirement := params.BeaconConfig().CustodyRequirement
+
+	tacgc.mut.RLock()
+	defer tacgc.mut.RUnlock()
+
+	return max(tacgc.value, custodyRequirement)
+}
+
+// Set sets the to advertise custody group count.
+func (tacgc *toAdverstiseCustodyGroupCount) Set(value uint64) {
+	tacgc.mut.Lock()
+	defer tacgc.mut.Unlock()
+
+	tacgc.value = value
+}
+
 // createInfoCacheIfNeeded creates a new cache if it doesn't exist.
 func createInfoCacheIfNeeded() error {
 	nodeInfoCacheMut.Lock()
@@ -129,58 +184,3 @@ func computeInfoCacheKey(nodeID enode.ID, custodyGroupCount uint64) [nodeInfoCac
 
 	return key
 }
-
-// setValidatorsCustodyRequirement sets the validators custody requirement.
-func (tcgc *targetCustodyGroupCount) SetValidatorsCustodyRequirement(value uint64) {
-	tcgc.mut.Lock()
-	defer tcgc.mut.Unlock()
-
-	tcgc.validatorsCustodyRequirement = value
-}
-
-// CustodyGroupCount returns the number of groups we should participate in for custody.
-func (tcgc *targetCustodyGroupCount) Get() uint64 {
-	// If subscribed to all subnets, return the number of custody groups.
-	if flags.Get().SubscribeToAllSubnets {
-		return params.BeaconConfig().NumberOfCustodyGroups
-	}
-
-	tcgc.mut.RLock()
-	defer tcgc.mut.RUnlock()
-
-	// If no validators are tracked, return the default custody requirement.
-	if tcgc.validatorsCustodyRequirement == 0 {
-		return params.BeaconConfig().CustodyRequirement
-	}
-
-	// Return the validators custody requirement.
-	return tcgc.validatorsCustodyRequirement
-}
-
-// Set sets the to advertise custody group count.
-func (tacgc *toAdverstiseCustodyGroupCount) Set(value uint64) {
-	tacgc.mut.Lock()
-	defer tacgc.mut.Unlock()
-
-	tacgc.value = value
-}
-
-// Get returns the to advertise custody group count.
-func (tacgc *toAdverstiseCustodyGroupCount) Get() uint64 {
-	// If subscribed to all subnets, return the number of custody groups.
-	if flags.Get().SubscribeToAllSubnets {
-		return params.BeaconConfig().NumberOfCustodyGroups
-	}
-
-	custodyRequirement := params.BeaconConfig().CustodyRequirement
-
-	tacgc.mut.RLock()
-	defer tacgc.mut.RUnlock()
-
-	return max(tacgc.value, custodyRequirement)
-}
-
-// ActualGroupCount returns the actual custody group count.
-func (custodyInfo *CustodyInfo) ActualGroupCount() uint64 {
-	return min(custodyInfo.TargetGroupCount.Get(), custodyInfo.ToAdvertiseGroupCount.Get())
-}

beacon-chain/core/peerdas/info_test.go

@@ -30,25 +30,25 @@ func TestInfo(t *testing.T) {
 func TestTargetCustodyGroupCount(t *testing.T) {
 	testCases := []struct {
 		name                         string
-		subscribeToAllSubnets        bool
+		subscribeToAllColumns        bool
 		validatorsCustodyRequirement uint64
 		expected                     uint64
 	}{
 		{
 			name:                         "subscribed to all subnets",
-			subscribeToAllSubnets:        true,
+			subscribeToAllColumns:        true,
 			validatorsCustodyRequirement: 100,
 			expected:                     128,
 		},
 		{
 			name:                         "no validators attached",
-			subscribeToAllSubnets:        false,
+			subscribeToAllColumns:        false,
 			validatorsCustodyRequirement: 0,
 			expected:                     4,
 		},
 		{
 			name:                         "some validators attached",
-			subscribeToAllSubnets:        false,
+			subscribeToAllColumns:        false,
 			validatorsCustodyRequirement: 100,
 			expected:                     100,
 		},
@@ -57,10 +57,10 @@ func TestTargetCustodyGroupCount(t *testing.T) {
 	for _, tc := range testCases {
 		t.Run(tc.name, func(t *testing.T) {
 			// Subscribe to all subnets if needed.
-			if tc.subscribeToAllSubnets {
+			if tc.subscribeToAllColumns {
 				resetFlags := flags.Get()
 				gFlags := new(flags.GlobalFlags)
-				gFlags.SubscribeToAllSubnets = true
+				gFlags.SubscribeAllDataSubnetsubnets = true
 				flags.Init(gFlags)
 				defer flags.Init(resetFlags)
 			}
@@ -82,25 +82,25 @@ func TestTargetCustodyGroupCount(t *testing.T) {
 func TestToAdvertiseCustodyGroupCount(t *testing.T) {
 	testCases := []struct {
 		name                         string
-		subscribeToAllSubnets        bool
+		subscribeToAllColumns        bool
 		toAdvertiseCustodyGroupCount uint64
 		expected                     uint64
 	}{
 		{
 			name:                         "subscribed to all subnets",
-			subscribeToAllSubnets:        true,
+			subscribeToAllColumns:        true,
 			toAdvertiseCustodyGroupCount: 100,
 			expected:                     128,
 		},
 		{
 			name:                         "higher than custody requirement",
-			subscribeToAllSubnets:        false,
+			subscribeToAllColumns:        false,
 			toAdvertiseCustodyGroupCount: 100,
 			expected:                     100,
 		},
 		{
 			name:                         "lower than custody requirement",
-			subscribeToAllSubnets:        false,
+			subscribeToAllColumns:        false,
 			toAdvertiseCustodyGroupCount: 1,
 			expected:                     4,
 		},
@@ -109,10 +109,10 @@ func TestToAdvertiseCustodyGroupCount(t *testing.T) {
 	for _, tc := range testCases {
 		t.Run(tc.name, func(t *testing.T) {
 			// Subscribe to all subnets if needed.
-			if tc.subscribeToAllSubnets {
+			if tc.subscribeToAllColumns {
 				resetFlags := flags.Get()
 				gFlags := new(flags.GlobalFlags)
-				gFlags.SubscribeToAllSubnets = true
+				gFlags.SubscribeAllDataSubnetsubnets = true
 				flags.Init(gFlags)
 				defer flags.Init(resetFlags)
 			}

beacon-chain/core/peerdas/p2p_interface.go

@@ -27,13 +27,13 @@ var (
 	ErrCannotLoadCustodyGroupCount = errors.New("cannot load the custody group count from peer")
 )
 
-// https://github.com/ethereum/consensus-specs/blob/v1.5.0-alpha.10/specs/fulu/p2p-interface.md#the-discovery-domain-discv5
+// https://github.com/ethereum/consensus-specs/blob/v1.5.0-beta.5/specs/fulu/p2p-interface.md#custody-group-count
 type Cgc uint64
 
 func (Cgc) ENRKey() string { return CustodyGroupCountEnrKey }
 
 // VerifyDataColumnSidecar verifies if the data column sidecar is valid.
-// https://github.com/ethereum/consensus-specs/blob/dev/specs/fulu/p2p-interface.md#verify_data_column_sidecar
+// https://github.com/ethereum/consensus-specs/blob/v1.5.0-beta.5/specs/fulu/p2p-interface.md#verify_data_column_sidecar
 func VerifyDataColumnSidecar(sidecar blocks.RODataColumn) error {
 	// The sidecar index must be within the valid range.
 	numberOfColumns := params.BeaconConfig().NumberOfColumns
@@ -60,7 +60,7 @@ func VerifyDataColumnSidecar(sidecar blocks.RODataColumn) error {
 // while we are verifying all the KZG proofs from multiple sidecars in a batch.
 // This is done to improve performance since the internal KZG library is way more
 // efficient when verifying in batch.
-// https://github.com/ethereum/consensus-specs/blob/dev/specs/fulu/p2p-interface.md#verify_data_column_sidecar_kzg_proofs
+// https://github.com/ethereum/consensus-specs/blob/v1.5.0-beta.5/specs/fulu/p2p-interface.md#verify_data_column_sidecar_kzg_proofs
 func VerifyDataColumnsSidecarKZGProofs(sidecars []blocks.RODataColumn) error {
 	// Compute the total count.
 	count := 0
@@ -96,7 +96,7 @@ func VerifyDataColumnsSidecarKZGProofs(sidecars []blocks.RODataColumn) error {
 }
 
 // VerifyDataColumnSidecarInclusionProof verifies if the given KZG commitments included in the given beacon block.
-// https://github.com/ethereum/consensus-specs/blob/dev/specs/fulu/p2p-interface.md#verify_data_column_sidecar_inclusion_proof
+// https://github.com/ethereum/consensus-specs/blob/v1.5.0-beta.5/specs/fulu/p2p-interface.md#verify_data_column_sidecar_inclusion_proof
 func VerifyDataColumnSidecarInclusionProof(sidecar blocks.RODataColumn) error {
 	if sidecar.SignedBlockHeader == nil || sidecar.SignedBlockHeader.Header == nil {
 		return ErrNilBlockHeader
@@ -128,7 +128,7 @@ func VerifyDataColumnSidecarInclusionProof(sidecar blocks.RODataColumn) error {
 }
 
 // ComputeSubnetForDataColumnSidecar computes the subnet for a data column sidecar.
-// https://github.com/ethereum/consensus-specs/blob/dev/specs/fulu/p2p-interface.md#compute_subnet_for_data_column_sidecar
+// https://github.com/ethereum/consensus-specs/blob/v1.5.0-beta.5/specs/fulu/p2p-interface.md#compute_subnet_for_data_column_sidecar
 func ComputeSubnetForDataColumnSidecar(columnIndex uint64) uint64 {
 	dataColumnSidecarSubnetCount := params.BeaconConfig().DataColumnSidecarSubnetCount
 	return columnIndex % dataColumnSidecarSubnetCount

beacon-chain/core/peerdas/p2p_interface_test.go

@@ -16,28 +16,6 @@ import (
 	"github.com/ethereum/go-ethereum/p2p/enr"
 )
 
-func createTestSidecar(t *testing.T, index uint64, column, kzgCommitments, kzgProofs [][]byte) blocks.RODataColumn {
-	pbSignedBeaconBlock := util.NewBeaconBlockDeneb()
-	signedBeaconBlock, err := blocks.NewSignedBeaconBlock(pbSignedBeaconBlock)
-	require.NoError(t, err)
-
-	signedBlockHeader, err := signedBeaconBlock.Header()
-	require.NoError(t, err)
-
-	sidecar := &ethpb.DataColumnSidecar{
-		Index:             index,
-		Column:            column,
-		KzgCommitments:    kzgCommitments,
-		KzgProofs:         kzgProofs,
-		SignedBlockHeader: signedBlockHeader,
-	}
-
-	roSidecar, err := blocks.NewRODataColumn(sidecar)
-	require.NoError(t, err)
-
-	return roSidecar
-}
-
 func TestVerifyDataColumnSidecar(t *testing.T) {
 	t.Run("index too large", func(t *testing.T) {
 		roSidecar := createTestSidecar(t, 1_000_000, nil, nil, nil)
@@ -332,3 +310,25 @@ func TestCustodyGroupCountFromRecord(t *testing.T) {
 		require.Equal(t, expected, actual)
 	})
 }
+
+func createTestSidecar(t *testing.T, index uint64, column, kzgCommitments, kzgProofs [][]byte) blocks.RODataColumn {
+	pbSignedBeaconBlock := util.NewBeaconBlockDeneb()
+	signedBeaconBlock, err := blocks.NewSignedBeaconBlock(pbSignedBeaconBlock)
+	require.NoError(t, err)
+
+	signedBlockHeader, err := signedBeaconBlock.Header()
+	require.NoError(t, err)
+
+	sidecar := &ethpb.DataColumnSidecar{
+		Index:             index,
+		Column:            column,
+		KzgCommitments:    kzgCommitments,
+		KzgProofs:         kzgProofs,
+		SignedBlockHeader: signedBlockHeader,
+	}
+
+	roSidecar, err := blocks.NewRODataColumn(sidecar)
+	require.NoError(t, err)
+
+	return roSidecar
+}

beacon-chain/core/peerdas/peer_sampling.go

@@ -8,7 +8,7 @@ import (
 
 // ExtendedSampleCount computes, for a given number of samples per slot and allowed failures the
 // number of samples we should actually query from peers.
-// https://github.com/ethereum/consensus-specs/blob/dev/specs/fulu/peer-sampling.md#get_extended_sample_count
+// https://github.com/ethereum/consensus-specs/blob/v1.5.0-beta.5/specs/fulu/peer-sampling.md#get_extended_sample_count
 func ExtendedSampleCount(samplesPerSlot, allowedFailures uint64) uint64 {
 	// Retrieve the columns count
 	columnsCount := params.BeaconConfig().NumberOfColumns

beacon-chain/core/peerdas/validator.go

@@ -0,0 +1,30 @@
+package peerdas
+
+import (
+	beaconState "github.com/OffchainLabs/prysm/v6/beacon-chain/state"
+	"github.com/OffchainLabs/prysm/v6/config/params"
+	"github.com/OffchainLabs/prysm/v6/consensus-types/primitives"
+	"github.com/pkg/errors"
+)
+
+// ValidatorsCustodyRequirement returns the number of custody groups regarding the validator indices attached to the beacon node.
+// https://github.com/ethereum/consensus-specs/blob/v1.5.0-beta.5/specs/fulu/validator.md#validator-custody
+func ValidatorsCustodyRequirement(state beaconState.ReadOnlyBeaconState, validatorsIndex map[primitives.ValidatorIndex]bool) (uint64, error) {
+	totalNodeBalance := uint64(0)
+	for index := range validatorsIndex {
+		balance, err := state.BalanceAtIndex(index)
+		if err != nil {
+			return 0, errors.Wrapf(err, "balance at index for validator index %v", index)
+		}
+
+		totalNodeBalance += balance
+	}
+
+	beaconConfig := params.BeaconConfig()
+	numberOfCustodyGroup := beaconConfig.NumberOfCustodyGroups
+	validatorCustodyRequirement := beaconConfig.ValidatorCustodyRequirement
+	balancePerAdditionalCustodyGroup := beaconConfig.BalancePerAdditionalCustodyGroup
+
+	count := totalNodeBalance / balancePerAdditionalCustodyGroup
+	return min(max(count, validatorCustodyRequirement), numberOfCustodyGroup), nil
+}

beacon-chain/core/peerdas/validator_test.go

@@ -0,0 +1,51 @@
+package peerdas_test
+
+import (
+	"testing"
+
+	"github.com/OffchainLabs/prysm/v6/beacon-chain/core/peerdas"
+	state_native "github.com/OffchainLabs/prysm/v6/beacon-chain/state/state-native"
+	"github.com/OffchainLabs/prysm/v6/consensus-types/primitives"
+	ethpb "github.com/OffchainLabs/prysm/v6/proto/prysm/v1alpha1"
+	"github.com/OffchainLabs/prysm/v6/testing/require"
+)
+
+func TestValidatorsCustodyRequirement(t *testing.T) {
+	testCases := []struct {
+		name     string
+		count    uint64
+		expected uint64
+	}{
+		{name: "0 validators", count: 0, expected: 8},
+		{name: "1 validator", count: 1, expected: 8},
+		{name: "8 validators", count: 8, expected: 8},
+		{name: "9 validators", count: 9, expected: 9},
+		{name: "100 validators", count: 100, expected: 100},
+		{name: "128 validators", count: 128, expected: 128},
+		{name: "129 validators", count: 129, expected: 128},
+		{name: "1000 validators", count: 1000, expected: 128},
+	}
+
+	const balance = uint64(32_000_000_000)
+
+	for _, tc := range testCases {
+		t.Run(tc.name, func(t *testing.T) {
+			balances := make([]uint64, 0, tc.count)
+			for range tc.count {
+				balances = append(balances, balance)
+			}
+
+			validatorsIndex := make(map[primitives.ValidatorIndex]bool)
+			for i := range tc.count {
+				validatorsIndex[primitives.ValidatorIndex(i)] = true
+			}
+
+			beaconState, err := state_native.InitializeFromProtoFulu(&ethpb.BeaconStateElectra{Balances: balances})
+			require.NoError(t, err)
+
+			actual, err := peerdas.ValidatorsCustodyRequirement(beaconState, validatorsIndex)
+			require.NoError(t, err)
+			require.Equal(t, tc.expected, actual)
+		})
+	}
+}

beacon-chain/das/availability_columns_test.go

@@ -228,7 +228,7 @@ func TestFullCommitmentsToCheck(t *testing.T) {
 		t.Run(tc.name, func(t *testing.T) {
 			resetFlags := flags.Get()
 			gFlags := new(flags.GlobalFlags)
-			gFlags.SubscribeToAllSubnets = true
+			gFlags.SubscribeAllDataSubnetsubnets = true
 			flags.Init(gFlags)
 			defer flags.Init(resetFlags)
 

beacon-chain/execution/engine_client.go

@@ -655,8 +655,16 @@ func (s *Service) ReconstructBlobSidecars(ctx context.Context, block interfaces.
 // ReconstructDataColumnSidecars reconstructs the verified data column sidecars for a given beacon block.
 // It retrieves the KZG commitments from the block body, fetches the associated blobs and cell proofs from the EL,
 // and constructs the corresponding verified read-only data column sidecars.
-func (s *Service) ReconstructDataColumnSidecars(ctx context.Context, block interfaces.ReadOnlySignedBeaconBlock, blockRoot [32]byte) ([]blocks.VerifiedRODataColumn, error) {
-	blockBody := block.Block().Body()
+func (s *Service) ReconstructDataColumnSidecars(ctx context.Context, signedROBlock interfaces.ReadOnlySignedBeaconBlock, blockRoot [fieldparams.RootLength]byte) ([]blocks.VerifiedRODataColumn, error) {
+	block := signedROBlock.Block()
+	blockBody := block.Body()
+	blockSlot := block.Slot()
+
+	log := log.WithFields(logrus.Fields{
+		"root": fmt.Sprintf("%#x", blockRoot),
+		"slot": blockSlot,
+	})
+
 	kzgCommitments, err := blockBody.BlobKzgCommitments()
 	if err != nil {
 		return nil, wrapWithBlockRoot(err, blockRoot, "blob KZG commitments")
@@ -674,30 +682,44 @@ func (s *Service) ReconstructDataColumnSidecars(ctx context.Context, block inter
 		return nil, wrapWithBlockRoot(err, blockRoot, "get blobs V2")
 	}
 
-	var cellsAndProofs []kzg.CellsAndProofs
+	// Return early if nothing is returned from the EL.
+	if len(blobAndProofV2s) == 0 {
+		log.Debug("No blobs returned from EL")
+		return nil, nil
+	}
+
+	// Compute all cells and proofs.
+	// Reminder: `engine_getBlobsV2` returns the (non extended) blob (64 cells),
+	// and the proofs corresponding to the extended blob (128 proofs, one per extended cell).
+	// We need to reconstruct the cells corresponding to the blob extension.
+	// https://github.com/ethereum/execution-apis/blob/main/src/engine/osaka.md#engine_getblobsv2
+	maxBlobCount := params.BeaconConfig().MaxBlobsPerBlock(blockSlot)
+	cellsAndProofs := make([]kzg.CellsAndProofs, 0, maxBlobCount)
 	for _, blobAndProof := range blobAndProofV2s {
 		if blobAndProof == nil {
-			return nil, wrapWithBlockRoot(errors.New("unable to reconstruct data column sidecars, did not get all blobs from EL"), blockRoot, "")
+			return nil, errors.Errorf("unable to reconstruct data column sidecars, did not get all blobs from EL for block %#x", blockRoot)
 		}
 
 		var blob kzg.Blob
 		copy(blob[:], blobAndProof.Blob)
+
 		cells, err := kzg.ComputeCells(&blob)
 		if err != nil {
-			return nil, wrapWithBlockRoot(err, blockRoot, "could not compute cells")
+			return nil, wrapWithBlockRoot(err, blockRoot, "compute cells")
 		}
 
-		proofs := make([]kzg.Proof, len(blobAndProof.KzgProofs))
-		for i, proof := range blobAndProof.KzgProofs {
-			proofs[i] = kzg.Proof(proof)
+		proofs := make([]kzg.Proof, 0, len(blobAndProof.KzgProofs))
+		for _, proof := range blobAndProof.KzgProofs {
+			proofs = append(proofs, kzg.Proof(proof))
 		}
+
 		cellsAndProofs = append(cellsAndProofs, kzg.CellsAndProofs{
 			Cells:  cells,
 			Proofs: proofs,
 		})
 	}
 
-	header, err := block.Header()
+	header, err := signedROBlock.Header()
 	if err != nil {
 		return nil, wrapWithBlockRoot(err, blockRoot, "could not get header")
 	}
@@ -723,10 +745,7 @@ func (s *Service) ReconstructDataColumnSidecars(ctx context.Context, block inter
 		verifiedRODataColumns[i] = blocks.NewVerifiedRODataColumn(roDataColumn)
 	}
 
-	log.WithFields(logrus.Fields{
-		"root": fmt.Sprintf("%#x", blockRoot),
-		"slot": block.Block().Slot(),
-	}).Debug("Data columns successfully reconstructed from EL")
+	log.Debug("Data columns successfully reconstructed from EL")
 
 	return verifiedRODataColumns, nil
 }

beacon-chain/execution/engine_client_test.go

@@ -2587,6 +2587,18 @@ func TestReconstructDataColumnSidecars(t *testing.T) {
 		require.ErrorContains(t, "get blobs V2 for block", err)
 	})
 
+	t.Run("nothing received", func(t *testing.T) {
+		srv := createBlobServerV2(t, 0, []bool{})
+		defer srv.Close()
+
+		rpcClient, client := setupRpcClientV2(t, srv.URL, client)
+		defer rpcClient.Close()
+
+		dataColumns, err := client.ReconstructDataColumnSidecars(ctx, sb, r)
+		require.NoError(t, err)
+		require.Equal(t, 0, len(dataColumns))
+	})
+
 	t.Run("receiving all blobs", func(t *testing.T) {
 		blobMasks := []bool{true, true, true, true, true, true}
 		srv := createBlobServerV2(t, 6, blobMasks)

beacon-chain/p2p/BUILD.bazel

@@ -59,6 +59,7 @@ go_library(
         "//config/features:go_default_library",
         "//config/fieldparams:go_default_library",
         "//config/params:go_default_library",
+        "//consensus-types/interfaces:go_default_library",
         "//consensus-types/primitives:go_default_library",
         "//consensus-types/wrapper:go_default_library",
         "//container/leaky-bucket:go_default_library",
@@ -145,6 +146,7 @@ go_test(
         "//beacon-chain/blockchain/testing:go_default_library",
         "//beacon-chain/cache:go_default_library",
         "//beacon-chain/core/helpers:go_default_library",
+        "//beacon-chain/core/light-client:go_default_library",
         "//beacon-chain/core/peerdas:go_default_library",
         "//beacon-chain/core/signing:go_default_library",
         "//beacon-chain/db/testing:go_default_library",
@@ -159,6 +161,7 @@ go_test(
         "//config/fieldparams:go_default_library",
         "//config/params:go_default_library",
         "//consensus-types/blocks:go_default_library",
+        "//consensus-types/interfaces:go_default_library",
         "//consensus-types/primitives:go_default_library",
         "//consensus-types/wrapper:go_default_library",
         "//container/leaky-bucket:go_default_library",
@@ -171,10 +174,12 @@ go_test(
         "//proto/prysm/v1alpha1:go_default_library",
         "//proto/prysm/v1alpha1/metadata:go_default_library",
         "//proto/testing:go_default_library",
+        "//runtime/version:go_default_library",
         "//testing/assert:go_default_library",
         "//testing/require:go_default_library",
         "//testing/util:go_default_library",
         "//time:go_default_library",
+        "//time/slots:go_default_library",
         "@com_github_ethereum_go_ethereum//crypto:go_default_library",
         "@com_github_ethereum_go_ethereum//p2p/discover:go_default_library",
         "@com_github_ethereum_go_ethereum//p2p/enode:go_default_library",

beacon-chain/p2p/broadcaster.go

@@ -11,9 +11,11 @@ import (
 	"github.com/OffchainLabs/prysm/v6/beacon-chain/core/helpers"
 	fieldparams "github.com/OffchainLabs/prysm/v6/config/fieldparams"
 	"github.com/OffchainLabs/prysm/v6/config/params"
+	"github.com/OffchainLabs/prysm/v6/consensus-types/interfaces"
 	"github.com/OffchainLabs/prysm/v6/crypto/hash"
 	"github.com/OffchainLabs/prysm/v6/monitoring/tracing"
 	"github.com/OffchainLabs/prysm/v6/monitoring/tracing/trace"
+	"github.com/OffchainLabs/prysm/v6/network/forks"
 	ethpb "github.com/OffchainLabs/prysm/v6/proto/prysm/v1alpha1"
 	"github.com/OffchainLabs/prysm/v6/time/slots"
 	"github.com/pkg/errors"
@@ -279,6 +281,58 @@ func (s *Service) internalBroadcastBlob(
 	}
 }
 
+func (s *Service) BroadcastLightClientOptimisticUpdate(ctx context.Context, update interfaces.LightClientOptimisticUpdate) error {
+	ctx, span := trace.StartSpan(ctx, "p2p.BroadcastLightClientOptimisticUpdate")
+	defer span.End()
+
+	if update == nil || update.IsNil() {
+		return errors.New("attempted to broadcast nil light client optimistic update")
+	}
+
+	forkDigest, err := forks.ForkDigestFromEpoch(slots.ToEpoch(update.AttestedHeader().Beacon().Slot), s.genesisValidatorsRoot)
+	if err != nil {
+		err := errors.Wrap(err, "could not retrieve fork digest")
+		tracing.AnnotateError(span, err)
+		return err
+	}
+
+	// TODO: should we check if the update is too early or too late to broadcast?
+
+	if err := s.broadcastObject(ctx, update, lcOptimisticToTopic(forkDigest)); err != nil {
+		err := errors.Wrap(err, "could not publish message")
+		tracing.AnnotateError(span, err)
+		return err
+	}
+
+	return nil
+}
+
+func (s *Service) BroadcastLightClientFinalityUpdate(ctx context.Context, update interfaces.LightClientFinalityUpdate) error {
+	ctx, span := trace.StartSpan(ctx, "p2p.BroadcastLightClientFinalityUpdate")
+	defer span.End()
+
+	if update == nil || update.IsNil() {
+		return errors.New("attempted to broadcast nil light client finality update")
+	}
+
+	forkDigest, err := forks.ForkDigestFromEpoch(slots.ToEpoch(update.AttestedHeader().Beacon().Slot), s.genesisValidatorsRoot)
+	if err != nil {
+		err := errors.Wrap(err, "could not retrieve fork digest")
+		tracing.AnnotateError(span, err)
+		return err
+	}
+
+	// TODO: should we check if the update is too early or too late to broadcast?
+
+	if err := s.broadcastObject(ctx, update, lcFinalityToTopic(forkDigest)); err != nil {
+		err := errors.Wrap(err, "could not publish message")
+		tracing.AnnotateError(span, err)
+		return err
+	}
+
+	return nil
+}
+
 // BroadcastDataColumn broadcasts a data column to the p2p network, the message is assumed to be
 // broadcasted to the current fork and to the input column subnet.
 // TODO: Add tests
@@ -434,6 +488,14 @@ func blobSubnetToTopic(subnet uint64, forkDigest [fieldparams.VersionLength]byte
 	return fmt.Sprintf(BlobSubnetTopicFormat, forkDigest, subnet)
 }
 
+func lcOptimisticToTopic(forkDigest [4]byte) string {
+	return fmt.Sprintf(LightClientOptimisticUpdateTopicFormat, forkDigest)
+}
+
+func lcFinalityToTopic(forkDigest [4]byte) string {
+	return fmt.Sprintf(LightClientFinalityUpdateTopicFormat, forkDigest)
+}
+
 func dataColumnSubnetToTopic(subnet uint64, forkDigest [fieldparams.VersionLength]byte) string {
 	return fmt.Sprintf(DataColumnSubnetTopicFormat, forkDigest, subnet)
 }

beacon-chain/p2p/broadcaster_test.go

@@ -11,19 +11,24 @@ import (
 
 	"github.com/OffchainLabs/prysm/v6/beacon-chain/blockchain/kzg"
 	"github.com/OffchainLabs/prysm/v6/beacon-chain/core/helpers"
+	lightClient "github.com/OffchainLabs/prysm/v6/beacon-chain/core/light-client"
 	"github.com/OffchainLabs/prysm/v6/beacon-chain/core/peerdas"
 	"github.com/OffchainLabs/prysm/v6/beacon-chain/p2p/peers"
 	"github.com/OffchainLabs/prysm/v6/beacon-chain/p2p/peers/scorers"
 	p2ptest "github.com/OffchainLabs/prysm/v6/beacon-chain/p2p/testing"
 	fieldparams "github.com/OffchainLabs/prysm/v6/config/fieldparams"
 	"github.com/OffchainLabs/prysm/v6/consensus-types/blocks"
+	"github.com/OffchainLabs/prysm/v6/consensus-types/interfaces"
 	"github.com/OffchainLabs/prysm/v6/consensus-types/wrapper"
 	"github.com/OffchainLabs/prysm/v6/encoding/bytesutil"
+	"github.com/OffchainLabs/prysm/v6/network/forks"
 	ethpb "github.com/OffchainLabs/prysm/v6/proto/prysm/v1alpha1"
 	testpb "github.com/OffchainLabs/prysm/v6/proto/testing"
+	"github.com/OffchainLabs/prysm/v6/runtime/version"
 	"github.com/OffchainLabs/prysm/v6/testing/assert"
 	"github.com/OffchainLabs/prysm/v6/testing/require"
 	"github.com/OffchainLabs/prysm/v6/testing/util"
+	"github.com/OffchainLabs/prysm/v6/time/slots"
 	pubsub "github.com/libp2p/go-libp2p-pubsub"
 	"github.com/libp2p/go-libp2p/core/host"
 	"github.com/prysmaticlabs/go-bitfield"
@@ -520,6 +525,140 @@ func TestService_BroadcastBlob(t *testing.T) {
 	require.Equal(t, false, util.WaitTimeout(&wg, 1*time.Second), "Failed to receive pubsub within 1s")
 }
 
+func TestService_BroadcastLightClientOptimisticUpdate(t *testing.T) {
+	p1 := p2ptest.NewTestP2P(t)
+	p2 := p2ptest.NewTestP2P(t)
+	p1.Connect(p2)
+	require.NotEqual(t, 0, len(p1.BHost.Network().Peers()))
+
+	p := &Service{
+		host:                  p1.BHost,
+		pubsub:                p1.PubSub(),
+		joinedTopics:          map[string]*pubsub.Topic{},
+		cfg:                   &Config{},
+		genesisTime:           time.Now(),
+		genesisValidatorsRoot: bytesutil.PadTo([]byte{'A'}, 32),
+		subnetsLock:           make(map[uint64]*sync.RWMutex),
+		subnetsLockLock:       sync.Mutex{},
+		peers: peers.NewStatus(context.Background(), &peers.StatusConfig{
+			ScorerParams: &scorers.Config{},
+		}),
+	}
+
+	l := util.NewTestLightClient(t, version.Altair)
+	msg, err := lightClient.NewLightClientOptimisticUpdateFromBeaconState(l.Ctx, l.State.Slot(), l.State, l.Block, l.AttestedState, l.AttestedBlock)
+	require.NoError(t, err)
+
+	GossipTypeMapping[reflect.TypeOf(msg)] = LightClientOptimisticUpdateTopicFormat
+	digest, err := forks.ForkDigestFromEpoch(slots.ToEpoch(msg.AttestedHeader().Beacon().Slot), p.genesisValidatorsRoot)
+	require.NoError(t, err)
+	topic := fmt.Sprintf(LightClientOptimisticUpdateTopicFormat, digest)
+
+	// External peer subscribes to the topic.
+	topic += p.Encoding().ProtocolSuffix()
+	sub, err := p2.SubscribeToTopic(topic)
+	require.NoError(t, err)
+
+	time.Sleep(50 * time.Millisecond) // libp2p fails without this delay...
+
+	// Async listen for the pubsub, must be before the broadcast.
+	var wg sync.WaitGroup
+	wg.Add(1)
+	go func(tt *testing.T) {
+		defer wg.Done()
+		ctx, cancel := context.WithTimeout(context.Background(), 1*time.Second)
+		defer cancel()
+
+		incomingMessage, err := sub.Next(ctx)
+		require.NoError(t, err)
+
+		result := &ethpb.LightClientOptimisticUpdateAltair{}
+		require.NoError(t, p.Encoding().DecodeGossip(incomingMessage.Data, result))
+		if !proto.Equal(result, msg.Proto()) {
+			tt.Errorf("Did not receive expected message, got %+v, wanted %+v", result, msg)
+		}
+	}(t)
+
+	// Broadcasting nil should fail.
+	ctx := context.Background()
+	require.ErrorContains(t, "attempted to broadcast nil", p.BroadcastLightClientOptimisticUpdate(ctx, nil))
+	var nilUpdate interfaces.LightClientOptimisticUpdate
+	require.ErrorContains(t, "attempted to broadcast nil", p.BroadcastLightClientOptimisticUpdate(ctx, nilUpdate))
+
+	// Broadcast to peers and wait.
+	require.NoError(t, p.BroadcastLightClientOptimisticUpdate(ctx, msg))
+	if util.WaitTimeout(&wg, 1*time.Second) {
+		t.Error("Failed to receive pubsub within 1s")
+	}
+}
+
+func TestService_BroadcastLightClientFinalityUpdate(t *testing.T) {
+	p1 := p2ptest.NewTestP2P(t)
+	p2 := p2ptest.NewTestP2P(t)
+	p1.Connect(p2)
+	require.NotEqual(t, 0, len(p1.BHost.Network().Peers()))
+
+	p := &Service{
+		host:                  p1.BHost,
+		pubsub:                p1.PubSub(),
+		joinedTopics:          map[string]*pubsub.Topic{},
+		cfg:                   &Config{},
+		genesisTime:           time.Now(),
+		genesisValidatorsRoot: bytesutil.PadTo([]byte{'A'}, 32),
+		subnetsLock:           make(map[uint64]*sync.RWMutex),
+		subnetsLockLock:       sync.Mutex{},
+		peers: peers.NewStatus(context.Background(), &peers.StatusConfig{
+			ScorerParams: &scorers.Config{},
+		}),
+	}
+
+	l := util.NewTestLightClient(t, version.Altair)
+	msg, err := lightClient.NewLightClientFinalityUpdateFromBeaconState(l.Ctx, l.State.Slot(), l.State, l.Block, l.AttestedState, l.AttestedBlock, l.FinalizedBlock)
+	require.NoError(t, err)
+
+	GossipTypeMapping[reflect.TypeOf(msg)] = LightClientFinalityUpdateTopicFormat
+	digest, err := forks.ForkDigestFromEpoch(slots.ToEpoch(msg.AttestedHeader().Beacon().Slot), p.genesisValidatorsRoot)
+	require.NoError(t, err)
+	topic := fmt.Sprintf(LightClientFinalityUpdateTopicFormat, digest)
+
+	// External peer subscribes to the topic.
+	topic += p.Encoding().ProtocolSuffix()
+	sub, err := p2.SubscribeToTopic(topic)
+	require.NoError(t, err)
+
+	time.Sleep(50 * time.Millisecond) // libp2p fails without this delay...
+
+	// Async listen for the pubsub, must be before the broadcast.
+	var wg sync.WaitGroup
+	wg.Add(1)
+	go func(tt *testing.T) {
+		defer wg.Done()
+		ctx, cancel := context.WithTimeout(context.Background(), 1*time.Second)
+		defer cancel()
+
+		incomingMessage, err := sub.Next(ctx)
+		require.NoError(t, err)
+
+		result := &ethpb.LightClientFinalityUpdateAltair{}
+		require.NoError(t, p.Encoding().DecodeGossip(incomingMessage.Data, result))
+		if !proto.Equal(result, msg.Proto()) {
+			tt.Errorf("Did not receive expected message, got %+v, wanted %+v", result, msg)
+		}
+	}(t)
+
+	// Broadcasting nil should fail.
+	ctx := context.Background()
+	require.ErrorContains(t, "attempted to broadcast nil", p.BroadcastLightClientFinalityUpdate(ctx, nil))
+	var nilUpdate interfaces.LightClientFinalityUpdate
+	require.ErrorContains(t, "attempted to broadcast nil", p.BroadcastLightClientFinalityUpdate(ctx, nilUpdate))
+
+	// Broadcast to peers and wait.
+	require.NoError(t, p.BroadcastLightClientFinalityUpdate(ctx, msg))
+	if util.WaitTimeout(&wg, 1*time.Second) {
+		t.Error("Failed to receive pubsub within 1s")
+	}
+}
+
 func TestService_BroadcastDataColumn(t *testing.T) {
 	require.NoError(t, kzg.Start())
 	p1 := p2ptest.NewTestP2P(t)

beacon-chain/p2p/discovery.go

@@ -106,7 +106,8 @@ func (l *listenerWrapper) RandomNodes() enode.Iterator {
 func (l *listenerWrapper) Ping(node *enode.Node) error {
 	l.mu.RLock()
 	defer l.mu.RUnlock()
-	return l.listener.Ping(node)
+	_, err := l.listener.Ping(node)
+	return err
 }
 
 func (l *listenerWrapper) RequestENR(node *enode.Node) (*enode.Node, error) {

beacon-chain/p2p/gossip_topic_mappings.go

@@ -22,6 +22,8 @@ var gossipTopicMappings = map[string]func() proto.Message{
 	SyncCommitteeSubnetTopicFormat:            func() proto.Message { return &ethpb.SyncCommitteeMessage{} },
 	BlsToExecutionChangeSubnetTopicFormat:     func() proto.Message { return &ethpb.SignedBLSToExecutionChange{} },
 	BlobSubnetTopicFormat:                     func() proto.Message { return &ethpb.BlobSidecar{} },
+	LightClientOptimisticUpdateTopicFormat:    func() proto.Message { return &ethpb.LightClientOptimisticUpdateAltair{} },
+	LightClientFinalityUpdateTopicFormat:      func() proto.Message { return &ethpb.LightClientFinalityUpdateAltair{} },
 	DataColumnSubnetTopicFormat:               func() proto.Message { return &ethpb.DataColumnSidecar{} },
 }
 
@@ -64,6 +66,25 @@ func GossipTopicMappings(topic string, epoch primitives.Epoch) proto.Message {
 			return &ethpb.SignedAggregateAttestationAndProofElectra{}
 		}
 		return gossipMessage(topic)
+	case LightClientOptimisticUpdateTopicFormat:
+		if epoch >= params.BeaconConfig().DenebForkEpoch {
+			return &ethpb.LightClientOptimisticUpdateDeneb{}
+		}
+		if epoch >= params.BeaconConfig().CapellaForkEpoch {
+			return &ethpb.LightClientOptimisticUpdateCapella{}
+		}
+		return gossipMessage(topic)
+	case LightClientFinalityUpdateTopicFormat:
+		if epoch >= params.BeaconConfig().ElectraForkEpoch {
+			return &ethpb.LightClientFinalityUpdateElectra{}
+		}
+		if epoch >= params.BeaconConfig().DenebForkEpoch {
+			return &ethpb.LightClientFinalityUpdateDeneb{}
+		}
+		if epoch >= params.BeaconConfig().CapellaForkEpoch {
+			return &ethpb.LightClientFinalityUpdateCapella{}
+		}
+		return gossipMessage(topic)
 	default:
 		return gossipMessage(topic)
 	}
@@ -98,21 +119,28 @@ func init() {
 
 	// Specially handle Altair objects.
 	GossipTypeMapping[reflect.TypeOf(&ethpb.SignedBeaconBlockAltair{})] = BlockSubnetTopicFormat
+	GossipTypeMapping[reflect.TypeOf(&ethpb.LightClientFinalityUpdateAltair{})] = LightClientFinalityUpdateTopicFormat
+	GossipTypeMapping[reflect.TypeOf(&ethpb.LightClientOptimisticUpdateAltair{})] = LightClientOptimisticUpdateTopicFormat
 
 	// Specially handle Bellatrix objects.
 	GossipTypeMapping[reflect.TypeOf(&ethpb.SignedBeaconBlockBellatrix{})] = BlockSubnetTopicFormat
 
 	// Specially handle Capella objects.
 	GossipTypeMapping[reflect.TypeOf(&ethpb.SignedBeaconBlockCapella{})] = BlockSubnetTopicFormat
+	GossipTypeMapping[reflect.TypeOf(&ethpb.LightClientOptimisticUpdateCapella{})] = LightClientOptimisticUpdateTopicFormat
+	GossipTypeMapping[reflect.TypeOf(&ethpb.LightClientFinalityUpdateCapella{})] = LightClientFinalityUpdateTopicFormat
 
 	// Specially handle Deneb objects.
 	GossipTypeMapping[reflect.TypeOf(&ethpb.SignedBeaconBlockDeneb{})] = BlockSubnetTopicFormat
+	GossipTypeMapping[reflect.TypeOf(&ethpb.LightClientOptimisticUpdateDeneb{})] = LightClientOptimisticUpdateTopicFormat
+	GossipTypeMapping[reflect.TypeOf(&ethpb.LightClientFinalityUpdateDeneb{})] = LightClientFinalityUpdateTopicFormat
 
 	// Specially handle Electra objects.
 	GossipTypeMapping[reflect.TypeOf(&ethpb.SignedBeaconBlockElectra{})] = BlockSubnetTopicFormat
 	GossipTypeMapping[reflect.TypeOf(&ethpb.SingleAttestation{})] = AttestationSubnetTopicFormat
 	GossipTypeMapping[reflect.TypeOf(&ethpb.AttesterSlashingElectra{})] = AttesterSlashingSubnetTopicFormat
 	GossipTypeMapping[reflect.TypeOf(&ethpb.SignedAggregateAttestationAndProofElectra{})] = AggregateAndProofSubnetTopicFormat
+	GossipTypeMapping[reflect.TypeOf(&ethpb.LightClientFinalityUpdateElectra{})] = LightClientFinalityUpdateTopicFormat
 
 	// Specially handle Fulu objects.
 	GossipTypeMapping[reflect.TypeOf(&ethpb.SignedBeaconBlockFulu{})] = BlockSubnetTopicFormat

beacon-chain/p2p/peers/scorers/bad_responses.go

@@ -101,6 +101,9 @@ func (s *BadResponsesScorer) countNoLock(pid peer.ID) (int, error) {
 // Increment increments the number of bad responses we have received from the given remote peer.
 // If peer doesn't exist this method is no-op.
 func (s *BadResponsesScorer) Increment(pid peer.ID) {
+	if pid == "" {
+		return
+	}
 	s.store.Lock()
 	defer s.store.Unlock()
 

beacon-chain/p2p/peers/scorers/block_providers.go

@@ -124,6 +124,9 @@ func (s *BlockProviderScorer) Params() *BlockProviderScorerConfig {
 
 // IncrementProcessedBlocks increments the number of blocks that have been successfully processed.
 func (s *BlockProviderScorer) IncrementProcessedBlocks(pid peer.ID, cnt uint64) {
+	if pid == "" {
+		return
+	}
 	s.store.Lock()
 	defer s.store.Unlock()
 	defer s.touchNoLock(pid)

beacon-chain/p2p/topics.go

@@ -30,6 +30,10 @@ const (
 	GossipBlsToExecutionChangeMessage = "bls_to_execution_change"
 	// GossipBlobSidecarMessage is the name for the blob sidecar message type.
 	GossipBlobSidecarMessage = "blob_sidecar"
+	// GossipLightClientFinalityUpdateMessage is the name for the light client finality update message type.
+	GossipLightClientFinalityUpdateMessage = "light_client_finality_update"
+	// GossipLightClientOptimisticUpdateMessage is the name for the light client optimistic update message type.
+	GossipLightClientOptimisticUpdateMessage = "light_client_optimistic_update"
 	// GossipDataColumnSidecarMessage is the name for the data column sidecar message type.
 	GossipDataColumnSidecarMessage = "data_column_sidecar"
 
@@ -55,6 +59,10 @@ const (
 	BlsToExecutionChangeSubnetTopicFormat = GossipProtocolAndDigest + GossipBlsToExecutionChangeMessage
 	// BlobSubnetTopicFormat is the topic format for the blob subnet.
 	BlobSubnetTopicFormat = GossipProtocolAndDigest + GossipBlobSidecarMessage + "_%d"
+	// LightClientFinalityUpdateTopicFormat is the topic format for the light client finality update subnet.
+	LightClientFinalityUpdateTopicFormat = GossipProtocolAndDigest + GossipLightClientFinalityUpdateMessage
+	// LightClientOptimisticUpdateTopicFormat is the topic format for the light client optimistic update subnet.
+	LightClientOptimisticUpdateTopicFormat = GossipProtocolAndDigest + GossipLightClientOptimisticUpdateMessage
 	// DataColumnSubnetTopicFormat is the topic format for the data column subnet.
 	DataColumnSubnetTopicFormat = GossipProtocolAndDigest + GossipDataColumnSidecarMessage + "_%d"
 )

beacon-chain/p2p/types/types.go

@@ -162,9 +162,9 @@ func (b *BlobSidecarsByRootReq) MarshalSSZ() ([]byte, error) {
 // BlobSidecarsByRootReq value.
 func (b *BlobSidecarsByRootReq) UnmarshalSSZ(buf []byte) error {
 	bufLen := len(buf)
-	maxLength := int(params.BeaconConfig().MaxRequestBlobSidecars) * blobIdSize
+	maxLength := int(params.BeaconConfig().MaxRequestBlobSidecarsElectra) * blobIdSize
 	if bufLen > maxLength {
-		return errors.Errorf("expected buffer with length of up to %d but received length %d", maxLength, bufLen)
+		return errors.Wrapf(ssz.ErrIncorrectListSize, "expected buffer with length of up to %d but received length %d", maxLength, bufLen)
 	}
 	if bufLen%blobIdSize != 0 {
 		return errors.Wrapf(ssz.ErrIncorrectByteSize, "size=%d", bufLen)

beacon-chain/p2p/types/types_test.go

@@ -43,6 +43,15 @@ func TestBlobSidecarsByRootReq_MarshalSSZ(t *testing.T) {
 			name: "10 item list",
 			ids:  generateBlobIdentifiers(10),
 		},
+		{
+			name: "max list",
+			ids:  generateBlobIdentifiers(int(params.BeaconConfig().MaxRequestBlobSidecarsElectra)),
+		},
+		{
+			name:         "beyond max list",
+			ids:          generateBlobIdentifiers(int(params.BeaconConfig().MaxRequestBlobSidecarsElectra) + 1),
+			unmarshalErr: ssz.ErrIncorrectListSize,
+		},
 		{
 			name: "wonky unmarshal size",
 			ids:  generateBlobIdentifiers(10),

beacon-chain/rpc/endpoints.go

@@ -894,6 +894,15 @@ func (s *Service) beaconEndpoints(
 			handler: server.GetPendingDeposits,
 			methods: []string{http.MethodGet},
 		},
+		{
+			template: "/eth/v1/beacon/states/{state_id}/pending_consolidations",
+			name:     namespace + ".GetPendingConsolidations",
+			middleware: []middleware.Middleware{
+				middleware.AcceptHeaderHandler([]string{api.JsonMediaType}),
+			},
+			handler: server.GetPendingDeposits,
+			methods: []string{http.MethodGet},
+		},
 		{
 			template: "/eth/v1/beacon/states/{state_id}/pending_partial_withdrawals",
 			name:     namespace + ".GetPendingPartialWithdrawals",
@@ -1041,6 +1050,7 @@ func (s *Service) eventsEndpoints() []endpoint {
 		HeadFetcher:            s.cfg.HeadFetcher,
 		ChainInfoFetcher:       s.cfg.ChainInfoFetcher,
 		TrackedValidatorsCache: s.cfg.TrackedValidatorsCache,
+		StateGen:               s.cfg.StateGen,
 	}
 
 	const namespace = "events"

beacon-chain/rpc/endpoints_test.go

@@ -30,6 +30,7 @@ func Test_endpoints(t *testing.T) {
 		"/eth/v1/beacon/states/{state_id}/randao":                      {http.MethodGet},
 		"/eth/v1/beacon/states/{state_id}/pending_deposits":            {http.MethodGet},
 		"/eth/v1/beacon/states/{state_id}/pending_partial_withdrawals": {http.MethodGet},
+		"/eth/v1/beacon/states/{state_id}/pending_consolidations":      {http.MethodGet},
 		"/eth/v1/beacon/headers":                                       {http.MethodGet},
 		"/eth/v1/beacon/headers/{block_id}":                            {http.MethodGet},
 		"/eth/v1/beacon/blinded_blocks":                                {http.MethodPost},

beacon-chain/rpc/eth/beacon/handlers.go

@@ -1613,6 +1613,62 @@ func (s *Server) broadcastSeenBlockSidecars(
 	return nil
 }
 
+// GetPendingConsolidations returns pending deposits for state with given 'stateId'.
+// Should return 400 if the state retrieved is prior to Electra.
+// Supports both JSON and SSZ responses based on Accept header.
+func (s *Server) GetPendingConsolidations(w http.ResponseWriter, r *http.Request) {
+	ctx, span := trace.StartSpan(r.Context(), "beacon.GetPendingDeposits")
+	defer span.End()
+
+	stateId := r.PathValue("state_id")
+	if stateId == "" {
+		httputil.HandleError(w, "state_id is required in URL params", http.StatusBadRequest)
+		return
+	}
+	st, err := s.Stater.State(ctx, []byte(stateId))
+	if err != nil {
+		shared.WriteStateFetchError(w, err)
+		return
+	}
+	if st.Version() < version.Electra {
+		httputil.HandleError(w, "state_id is prior to electra", http.StatusBadRequest)
+		return
+	}
+	pd, err := st.PendingConsolidations()
+	if err != nil {
+		httputil.HandleError(w, "Could not get pending consolidations: "+err.Error(), http.StatusInternalServerError)
+		return
+	}
+	w.Header().Set(api.VersionHeader, version.String(st.Version()))
+	if httputil.RespondWithSsz(r) {
+		sszData, err := serializeItems(pd)
+		if err != nil {
+			httputil.HandleError(w, "Failed to serialize pending consolidations: "+err.Error(), http.StatusInternalServerError)
+			return
+		}
+		httputil.WriteSsz(w, sszData)
+	} else {
+		isOptimistic, err := helpers.IsOptimistic(ctx, []byte(stateId), s.OptimisticModeFetcher, s.Stater, s.ChainInfoFetcher, s.BeaconDB)
+		if err != nil {
+			httputil.HandleError(w, "Could not check optimistic status: "+err.Error(), http.StatusInternalServerError)
+			return
+		}
+		blockRoot, err := st.LatestBlockHeader().HashTreeRoot()
+		if err != nil {
+			httputil.HandleError(w, "Could not calculate root of latest block header: "+err.Error(), http.StatusInternalServerError)
+			return
+		}
+		isFinalized := s.FinalizationFetcher.IsFinalized(ctx, blockRoot)
+		resp := structs.GetPendingConsolidationsResponse{
+			Version:             version.String(st.Version()),
+			ExecutionOptimistic: isOptimistic,
+			Finalized:           isFinalized,
+			Data:                structs.PendingConsolidationsFromConsensus(pd),
+		}
+		httputil.WriteJson(w, resp)
+	}
+}
+
 // GetPendingDeposits returns pending deposits for state with given 'stateId'.
 // Should return 400 if the state retrieved is prior to Electra.
 // Supports both JSON and SSZ responses based on Accept header.

beacon-chain/rpc/eth/beacon/handlers_test.go

@@ -4755,6 +4755,191 @@ func Test_validateBlobSidecars(t *testing.T) {
 	require.ErrorContains(t, "could not verify blob proof: can't verify opening proof", s.validateBlobSidecars(b, [][]byte{blob[:]}, [][]byte{proof[:]}))
 }
 
+func TestGetPendingConsolidations(t *testing.T) {
+	st, _ := util.DeterministicGenesisStateElectra(t, 10)
+
+	cs := make([]*eth.PendingConsolidation, 10)
+	for i := 0; i < len(cs); i += 1 {
+		cs[i] = &eth.PendingConsolidation{
+			SourceIndex: primitives.ValidatorIndex(i),
+			TargetIndex: primitives.ValidatorIndex(i + 1),
+		}
+	}
+	require.NoError(t, st.SetPendingConsolidations(cs))
+
+	chainService := &chainMock.ChainService{
+		Optimistic:     false,
+		FinalizedRoots: map[[32]byte]bool{},
+	}
+	server := &Server{
+		Stater: &testutil.MockStater{
+			BeaconState: st,
+		},
+		OptimisticModeFetcher: chainService,
+		FinalizationFetcher:   chainService,
+	}
+
+	t.Run("json response", func(t *testing.T) {
+		req := httptest.NewRequest(http.MethodGet, "http://example.com/eth/v1/beacon/states/{state_id}/pending_consolidations", nil)
+		req.SetPathValue("state_id", "head")
+		rec := httptest.NewRecorder()
+		rec.Body = new(bytes.Buffer)
+
+		server.GetPendingConsolidations(rec, req)
+		require.Equal(t, http.StatusOK, rec.Code)
+		require.Equal(t, "electra", rec.Header().Get(api.VersionHeader))
+
+		var resp structs.GetPendingConsolidationsResponse
+		require.NoError(t, json.Unmarshal(rec.Body.Bytes(), &resp))
+
+		expectedVersion := version.String(st.Version())
+		require.Equal(t, expectedVersion, resp.Version)
+
+		require.Equal(t, false, resp.ExecutionOptimistic)
+		require.Equal(t, false, resp.Finalized)
+
+		expectedConsolidations := structs.PendingConsolidationsFromConsensus(cs)
+		require.DeepEqual(t, expectedConsolidations, resp.Data)
+	})
+	t.Run("ssz response", func(t *testing.T) {
+		req := httptest.NewRequest(http.MethodGet, "http://example.com/eth/v1/beacon/states/{state_id}/pending_consolidations", nil)
+		req.Header.Set("Accept", "application/octet-stream")
+		req.SetPathValue("state_id", "head")
+		rec := httptest.NewRecorder()
+		rec.Body = new(bytes.Buffer)
+
+		server.GetPendingConsolidations(rec, req)
+		require.Equal(t, http.StatusOK, rec.Code)
+		require.Equal(t, "electra", rec.Header().Get(api.VersionHeader))
+
+		responseBytes := rec.Body.Bytes()
+		var recoveredConsolidations []*eth.PendingConsolidation
+
+		// Verify total size matches expected number of deposits
+		consolidationSize := (&eth.PendingConsolidation{}).SizeSSZ()
+		require.Equal(t, len(responseBytes), consolidationSize*len(cs))
+
+		for i := 0; i < len(cs); i++ {
+			start := i * consolidationSize
+			end := start + consolidationSize
+
+			var c eth.PendingConsolidation
+			require.NoError(t, c.UnmarshalSSZ(responseBytes[start:end]))
+			recoveredConsolidations = append(recoveredConsolidations, &c)
+		}
+		require.DeepEqual(t, cs, recoveredConsolidations)
+	})
+	t.Run("pre electra state", func(t *testing.T) {
+		preElectraSt, _ := util.DeterministicGenesisStateDeneb(t, 1)
+		preElectraServer := &Server{
+			Stater: &testutil.MockStater{
+				BeaconState: preElectraSt,
+			},
+			OptimisticModeFetcher: chainService,
+			FinalizationFetcher:   chainService,
+		}
+
+		// Test JSON request
+		req := httptest.NewRequest(http.MethodGet, "http://example.com/eth/v1/beacon/states/{state_id}/pending_consolidations", nil)
+		req.SetPathValue("state_id", "head")
+		rec := httptest.NewRecorder()
+		rec.Body = new(bytes.Buffer)
+
+		preElectraServer.GetPendingConsolidations(rec, req)
+		require.Equal(t, http.StatusBadRequest, rec.Code)
+
+		var errResp struct {
+			Code    int    `json:"code"`
+			Message string `json:"message"`
+		}
+		require.NoError(t, json.Unmarshal(rec.Body.Bytes(), &errResp))
+		require.Equal(t, "state_id is prior to electra", errResp.Message)
+
+		// Test SSZ request
+		sszReq := httptest.NewRequest(http.MethodGet, "http://example.com/eth/v1/beacon/states/{state_id}/pending_consolidations", nil)
+		sszReq.Header.Set("Accept", "application/octet-stream")
+		sszReq.SetPathValue("state_id", "head")
+		sszRec := httptest.NewRecorder()
+		sszRec.Body = new(bytes.Buffer)
+
+		preElectraServer.GetPendingConsolidations(sszRec, sszReq)
+		require.Equal(t, http.StatusBadRequest, sszRec.Code)
+
+		var sszErrResp struct {
+			Code    int    `json:"code"`
+			Message string `json:"message"`
+		}
+		require.NoError(t, json.Unmarshal(sszRec.Body.Bytes(), &sszErrResp))
+		require.Equal(t, "state_id is prior to electra", sszErrResp.Message)
+	})
+	t.Run("missing state_id parameter", func(t *testing.T) {
+		req := httptest.NewRequest(http.MethodGet, "http://example.com/eth/v1/beacon/states/{state_id}/pending_consolidations", nil)
+		// Intentionally not setting state_id
+		rec := httptest.NewRecorder()
+		rec.Body = new(bytes.Buffer)
+
+		server.GetPendingConsolidations(rec, req)
+		require.Equal(t, http.StatusBadRequest, rec.Code)
+
+		var errResp struct {
+			Code    int    `json:"code"`
+			Message string `json:"message"`
+		}
+		require.NoError(t, json.Unmarshal(rec.Body.Bytes(), &errResp))
+		require.Equal(t, "state_id is required in URL params", errResp.Message)
+	})
+	t.Run("optimistic node", func(t *testing.T) {
+		optimisticChainService := &chainMock.ChainService{
+			Optimistic:     true,
+			FinalizedRoots: map[[32]byte]bool{},
+		}
+		optimisticServer := &Server{
+			Stater:                server.Stater,
+			OptimisticModeFetcher: optimisticChainService,
+			FinalizationFetcher:   optimisticChainService,
+		}
+
+		req := httptest.NewRequest(http.MethodGet, "http://example.com/eth/v1/beacon/states/{state_id}/pending_consolidations", nil)
+		req.SetPathValue("state_id", "head")
+		rec := httptest.NewRecorder()
+		rec.Body = new(bytes.Buffer)
+
+		optimisticServer.GetPendingConsolidations(rec, req)
+		require.Equal(t, http.StatusOK, rec.Code)
+
+		var resp structs.GetPendingConsolidationsResponse
+		require.NoError(t, json.Unmarshal(rec.Body.Bytes(), &resp))
+		require.Equal(t, true, resp.ExecutionOptimistic)
+	})
+
+	t.Run("finalized node", func(t *testing.T) {
+		blockRoot, err := st.LatestBlockHeader().HashTreeRoot()
+		require.NoError(t, err)
+
+		finalizedChainService := &chainMock.ChainService{
+			Optimistic:     false,
+			FinalizedRoots: map[[32]byte]bool{blockRoot: true},
+		}
+		finalizedServer := &Server{
+			Stater:                server.Stater,
+			OptimisticModeFetcher: finalizedChainService,
+			FinalizationFetcher:   finalizedChainService,
+		}
+
+		req := httptest.NewRequest(http.MethodGet, "http://example.com/eth/v1/beacon/states/{state_id}/pending_consolidations", nil)
+		req.SetPathValue("state_id", "head")
+		rec := httptest.NewRecorder()
+		rec.Body = new(bytes.Buffer)
+
+		finalizedServer.GetPendingConsolidations(rec, req)
+		require.Equal(t, http.StatusOK, rec.Code)
+
+		var resp structs.GetPendingConsolidationsResponse
+		require.NoError(t, json.Unmarshal(rec.Body.Bytes(), &resp))
+		require.Equal(t, true, resp.Finalized)
+	})
+}
+
 func TestGetPendingDeposits(t *testing.T) {
 	st, _ := util.DeterministicGenesisStateElectra(t, 10)
 

beacon-chain/rpc/eth/events/BUILD.bazel

@@ -20,6 +20,7 @@ go_library(
         "//beacon-chain/core/helpers:go_default_library",
         "//beacon-chain/core/transition:go_default_library",
         "//beacon-chain/state:go_default_library",
+        "//beacon-chain/state/stategen:go_default_library",
         "//config/params:go_default_library",
         "//consensus-types/interfaces:go_default_library",
         "//consensus-types/payload-attribute:go_default_library",
@@ -53,6 +54,7 @@ go_test(
         "//beacon-chain/core/feed/operation:go_default_library",
         "//beacon-chain/core/feed/state:go_default_library",
         "//beacon-chain/state:go_default_library",
+        "//beacon-chain/state/stategen/mock:go_default_library",
         "//config/fieldparams:go_default_library",
         "//config/params:go_default_library",
         "//consensus-types/blocks:go_default_library",

beacon-chain/rpc/eth/events/events.go

@@ -37,7 +37,6 @@ import (
 )
 
 const DefaultEventFeedDepth = 1000
-const payloadAttributeTimeout = 2 * time.Second
 
 const (
 	InvalidTopic = "__invalid__"
@@ -627,6 +626,7 @@ func (s *Server) lazyReaderForEvent(ctx context.Context, event *feed.Event, topi
 }
 
 var errUnsupportedPayloadAttribute = errors.New("cannot compute payload attributes pre-Bellatrix")
+var errPayloadAttributeExpired = errors.New("skipping payload attribute event for past slot")
 
 func (s *Server) computePayloadAttributes(ctx context.Context, st state.ReadOnlyBeaconState, root [32]byte, proposer primitives.ValidatorIndex, timestamp uint64, randao []byte) (payloadattribute.Attributer, error) {
 	v := st.Version()
@@ -681,48 +681,48 @@ var zeroRoot [32]byte
 // needsFill allows tests to provide filled EventData values. An ordinary event data value fired by the blockchain package will have
 // all of the checked fields empty, so the logical short circuit should hit immediately.
 func needsFill(ev payloadattribute.EventData) bool {
-	return ev.HeadState == nil || ev.HeadState.IsNil() || ev.HeadState.LatestBlockHeader() == nil ||
-		ev.HeadBlock == nil || ev.HeadBlock.IsNil() ||
-		ev.HeadRoot == zeroRoot || len(ev.ParentBlockRoot) == 0 || len(ev.ParentBlockHash) == 0 ||
+	return len(ev.ParentBlockHash) == 0 ||
 		ev.Attributer == nil || ev.Attributer.IsEmpty()
 }
 
 func (s *Server) fillEventData(ctx context.Context, ev payloadattribute.EventData) (payloadattribute.EventData, error) {
-	var err error
-
 	if !needsFill(ev) {
 		return ev, nil
 	}
-
-	ev.HeadState, err = s.HeadFetcher.HeadState(ctx)
-	if err != nil {
-		return ev, errors.Wrap(err, "could not get head state")
+	if ev.HeadBlock == nil || ev.HeadBlock.IsNil() {
+		return ev, errors.New("head block is nil")
+	}
+	if ev.HeadRoot == zeroRoot {
+		return ev, errors.New("head root is empty")
 	}
 
-	ev.HeadBlock, err = s.HeadFetcher.HeadBlock(ctx)
-	if err != nil {
-		return ev, errors.Wrap(err, "could not look up head block")
-	}
-	ev.HeadRoot, err = ev.HeadBlock.Block().HashTreeRoot()
-	if err != nil {
-		return ev, errors.Wrap(err, "could not compute head block root")
-	}
-	pr := ev.HeadBlock.Block().ParentRoot()
-	ev.ParentBlockRoot = pr[:]
-
-	hsr, err := ev.HeadState.LatestBlockHeader().HashTreeRoot()
-	if err != nil {
-		return ev, errors.Wrap(err, "could not compute latest block header root")
-	}
+	var err error
+	var st state.BeaconState
 
+	// If head is in the same block as the proposal slot, we can use the "read only" state cache.
 	pse := slots.ToEpoch(ev.ProposalSlot)
-	st := ev.HeadState
-	if slots.ToEpoch(st.Slot()) != pse {
-		st, err = transition.ProcessSlotsUsingNextSlotCache(ctx, st, hsr[:], ev.ProposalSlot)
+	if slots.ToEpoch(ev.HeadBlock.Block().Slot()) == pse {
+		st = s.StateGen.StateByRootIfCachedNoCopy(ev.HeadRoot)
+	}
+	// If st is nil, we couldn't get the state from the cache, or it isn't in the same epoch.
+	if st == nil || st.IsNil() {
+		st, err = s.StateGen.StateByRoot(ctx, ev.HeadRoot)
 		if err != nil {
-			return ev, errors.Wrap(err, "could not run process blocks on head state into the proposal slot epoch")
+			return ev, errors.Wrap(err, "could not get head state")
+		}
+		// double check that we need to process_slots, just in case we got here via a hot state cache miss.
+		if slots.ToEpoch(st.Slot()) < pse {
+			start, err := slots.EpochStart(pse)
+			if err != nil {
+				return ev, errors.Wrap(err, "invalid state slot; could not compute epoch start")
+			}
+			st, err = transition.ProcessSlotsUsingNextSlotCache(ctx, st, ev.HeadRoot[:], start)
+			if err != nil {
+				return ev, errors.Wrap(err, "could not run process blocks on head state into the proposal slot epoch")
+			}
 		}
 	}
+
 	ev.ProposerIndex, err = helpers.BeaconProposerIndexAtSlot(ctx, st, ev.ProposalSlot)
 	if err != nil {
 		return ev, errors.Wrap(err, "failed to compute proposer index")
@@ -743,14 +743,18 @@ func (s *Server) fillEventData(ctx context.Context, ev payloadattribute.EventDat
 	if err != nil {
 		return ev, errors.Wrap(err, "could not get head state slot time")
 	}
-	ev.Attributer, err = s.computePayloadAttributes(ctx, st, hsr, ev.ProposerIndex, uint64(t.Unix()), randao)
+	ev.Attributer, err = s.computePayloadAttributes(ctx, st, ev.HeadRoot, ev.ProposerIndex, uint64(t.Unix()), randao)
 	return ev, err
 }
 
 // This event stream is intended to be used by builders and relays.
 // Parent fields are based on state at N_{current_slot}, while the rest of fields are based on state of N_{current_slot + 1}
 func (s *Server) payloadAttributesReader(ctx context.Context, ev payloadattribute.EventData) (lazyReader, error) {
-	ctx, cancel := context.WithTimeout(ctx, payloadAttributeTimeout)
+	deadline := slots.BeginsAt(ev.ProposalSlot, s.ChainInfoFetcher.GenesisTime())
+	if deadline.Before(time.Now()) {
+		return nil, errors.Wrapf(errPayloadAttributeExpired, "proposal slot time %d", deadline.Unix())
+	}
+	ctx, cancel := context.WithDeadline(ctx, deadline)
 	edc := make(chan asyncPayloadAttrData)
 	go func() {
 		d := asyncPayloadAttrData{}
@@ -772,7 +776,7 @@ func (s *Server) payloadAttributesReader(ctx context.Context, ev payloadattribut
 			ProposerIndex:     strconv.FormatUint(uint64(ev.ProposerIndex), 10),
 			ProposalSlot:      strconv.FormatUint(uint64(ev.ProposalSlot), 10),
 			ParentBlockNumber: strconv.FormatUint(ev.ParentBlockNumber, 10),
-			ParentBlockRoot:   hexutil.Encode(ev.ParentBlockRoot),
+			ParentBlockRoot:   hexutil.Encode(ev.HeadRoot[:]),
 			ParentBlockHash:   hexutil.Encode(ev.ParentBlockHash),
 			PayloadAttributes: attributesBytes,
 		})

beacon-chain/rpc/eth/events/events_test.go

@@ -18,6 +18,7 @@ import (
 	"github.com/OffchainLabs/prysm/v6/beacon-chain/core/feed/operation"
 	statefeed "github.com/OffchainLabs/prysm/v6/beacon-chain/core/feed/state"
 	"github.com/OffchainLabs/prysm/v6/beacon-chain/state"
+	"github.com/OffchainLabs/prysm/v6/beacon-chain/state/stategen/mock"
 	fieldparams "github.com/OffchainLabs/prysm/v6/config/fieldparams"
 	"github.com/OffchainLabs/prysm/v6/config/params"
 	"github.com/OffchainLabs/prysm/v6/consensus-types/blocks"
@@ -522,15 +523,22 @@ func TestStreamEvents_OperationsEvents(t *testing.T) {
 				// to avoid slot processing
 				require.NoError(t, st.SetSlot(currentSlot+1))
 				b := tc.getBlock()
+				genesis := time.Now()
+				require.NoError(t, st.SetGenesisTime(uint64(genesis.Unix())))
 				mockChainService := &mockChain.ChainService{
-					Root:  make([]byte, 32),
-					State: st,
-					Block: b,
-					Slot:  &currentSlot,
+					Root:    make([]byte, 32),
+					State:   st,
+					Block:   b,
+					Slot:    &currentSlot,
+					Genesis: genesis,
 				}
+				headRoot, err := b.Block().HashTreeRoot()
+				require.NoError(t, err)
 
 				stn := mockChain.NewEventFeedWrapper()
 				opn := mockChain.NewEventFeedWrapper()
+				stategen := mock.NewService()
+				stategen.AddStateForRoot(st, headRoot)
 				s := &Server{
 					StateNotifier:          &mockChain.SimpleNotifier{Feed: stn},
 					OperationNotifier:      &mockChain.SimpleNotifier{Feed: opn},
@@ -538,6 +546,7 @@ func TestStreamEvents_OperationsEvents(t *testing.T) {
 					ChainInfoFetcher:       mockChainService,
 					TrackedValidatorsCache: cache.NewTrackedValidatorsCache(),
 					EventWriteTimeout:      testEventWriteTimeout,
+					StateGen:               stategen,
 				}
 				if tc.SetTrackedValidatorsCache != nil {
 					tc.SetTrackedValidatorsCache(s.TrackedValidatorsCache)
@@ -551,13 +560,11 @@ func TestStreamEvents_OperationsEvents(t *testing.T) {
 						Type: statefeed.PayloadAttributes,
 						Data: payloadattribute.EventData{
 							ProposerIndex:     0,
-							ProposalSlot:      0,
+							ProposalSlot:      mockChainService.CurrentSlot() + 1,
 							ParentBlockNumber: 0,
-							ParentBlockRoot:   make([]byte, 32),
 							ParentBlockHash:   make([]byte, 32),
-							HeadState:         st,
 							HeadBlock:         b,
-							HeadRoot:          [fieldparams.RootLength]byte{},
+							HeadRoot:          headRoot,
 						},
 					},
 				}
@@ -575,8 +582,6 @@ func TestStreamEvents_OperationsEvents(t *testing.T) {
 func TestFillEventData(t *testing.T) {
 	ctx := context.Background()
 	t.Run("AlreadyFilledData_ShouldShortCircuitWithoutError", func(t *testing.T) {
-		st, err := util.NewBeaconStateBellatrix()
-		require.NoError(t, err)
 		b, err := blocks.NewSignedBeaconBlock(util.HydrateSignedBeaconBlockBellatrix(&eth.SignedBeaconBlockBellatrix{}))
 		require.NoError(t, err)
 		attributor, err := payloadattribute.New(&enginev1.PayloadAttributes{
@@ -584,11 +589,9 @@ func TestFillEventData(t *testing.T) {
 		})
 		require.NoError(t, err)
 		alreadyFilled := payloadattribute.EventData{
-			HeadState:       st,
 			HeadBlock:       b,
 			HeadRoot:        [32]byte{1, 2, 3},
 			Attributer:      attributor,
-			ParentBlockRoot: []byte{1, 2, 3},
 			ParentBlockHash: []byte{4, 5, 6},
 		}
 		srv := &Server{} // No real HeadFetcher needed here since it won't be called.
@@ -612,12 +615,14 @@ func TestFillEventData(t *testing.T) {
 			Timestamp: uint64(time.Now().Unix()),
 		})
 		require.NoError(t, err)
+		headRoot, err := b.Block().HashTreeRoot()
+		require.NoError(t, err)
 		// Create an event data object missing certain fields:
 		partial := payloadattribute.EventData{
-			// The presence of a nil HeadState, nil HeadBlock, zeroed HeadRoot, etc.
-			// will cause fillEventData to try to fill the values.
 			ProposalSlot: 42,         // different epoch from current slot
 			Attributer:   attributor, // Must be Bellatrix or later
+			HeadBlock:    b,
+			HeadRoot:     headRoot,
 		}
 		currentSlot := primitives.Slot(0)
 		// to avoid slot processing
@@ -629,6 +634,8 @@ func TestFillEventData(t *testing.T) {
 			Slot:  &currentSlot,
 		}
 
+		stategen := mock.NewService()
+		stategen.AddStateForRoot(st, headRoot)
 		stn := mockChain.NewEventFeedWrapper()
 		opn := mockChain.NewEventFeedWrapper()
 		srv := &Server{
@@ -638,16 +645,15 @@ func TestFillEventData(t *testing.T) {
 			ChainInfoFetcher:       mockChainService,
 			TrackedValidatorsCache: cache.NewTrackedValidatorsCache(),
 			EventWriteTimeout:      testEventWriteTimeout,
+			StateGen:               stategen,
 		}
 
 		filled, err := srv.fillEventData(ctx, partial)
 		require.NoError(t, err, "expected successful fill of partial event data")
 
 		// Verify that fields have been updated from the mock data:
-		require.NotNil(t, filled.HeadState, "HeadState should be assigned")
 		require.NotNil(t, filled.HeadBlock, "HeadBlock should be assigned")
 		require.NotEqual(t, [32]byte{}, filled.HeadRoot, "HeadRoot should no longer be zero")
-		require.NotEmpty(t, filled.ParentBlockRoot, "ParentBlockRoot should be filled")
 		require.NotEmpty(t, filled.ParentBlockHash, "ParentBlockHash should be filled")
 		require.Equal(t, uint64(0), filled.ParentBlockNumber, "ParentBlockNumber must match mock block")
 

beacon-chain/rpc/eth/events/server.go

@@ -10,6 +10,7 @@ import (
 	"github.com/OffchainLabs/prysm/v6/beacon-chain/cache"
 	opfeed "github.com/OffchainLabs/prysm/v6/beacon-chain/core/feed/operation"
 	statefeed "github.com/OffchainLabs/prysm/v6/beacon-chain/core/feed/state"
+	"github.com/OffchainLabs/prysm/v6/beacon-chain/state/stategen"
 )
 
 // Server defines a server implementation of the http events service,
@@ -23,4 +24,5 @@ type Server struct {
 	KeepAliveInterval      time.Duration
 	EventFeedDepth         int
 	EventWriteTimeout      time.Duration
+	StateGen               stategen.StateManager
 }

beacon-chain/rpc/lookup/blocker.go

@@ -4,7 +4,6 @@ import (
 	"context"
 	"fmt"
 	"math"
-	"slices"
 	"strconv"
 
 	"github.com/OffchainLabs/prysm/v6/beacon-chain/blockchain"
@@ -136,16 +135,6 @@ func (p *BeaconDbBlocker) Block(ctx context.Context, id []byte) (interfaces.Read
 	return blk, nil
 }
 
-// uint64MapToSortedSlice produces a sorted uint64 slice from a map.
-func uint64MapToSortedSlice(input map[uint64]bool) []uint64 {
-	output := make([]uint64, 0, len(input))
-	for idx := range input {
-		output = append(output, idx)
-	}
-	slices.Sort[[]uint64](output)
-	return output
-}
-
 // blobsFromStoredBlobs retrieves blobs corresponding to `indices` and `root` from the store.
 // This function expects blobs to be stored directly (aka. no data columns).
 func (p *BeaconDbBlocker) blobsFromStoredBlobs(
@@ -342,7 +331,7 @@ func (p *BeaconDbBlocker) blobsFromStoredDataColumns(indices map[uint64]bool, ro
 	if !canReconstruct {
 		// There is no way to reconstruct the data columns.
 		return nil, &core.RpcError{
-			Err:    errors.Errorf("the node does not custody enough data columns to reconstruct blobs. Please start the beacon node with the `--%s` flag to ensure this call to success, or retry later if it already the case.", flags.SubscribeToAllSubnets.Name),
+			Err:    errors.Errorf("the node does not custody enough data columns to reconstruct blobs. Please start the beacon node with the `--%s` flag to ensure this call to success, or retry later if it already the case.", flags.SubscribeAllDataSubnets.Name),
 			Reason: core.NotFound,
 		}
 	}

beacon-chain/rpc/prysm/v1alpha1/beacon/assignments.go

@@ -18,7 +18,7 @@ import (
 
 const errEpoch = "cannot retrieve information about an epoch in the future, current epoch %d, requesting %d"
 
-// Deprecated: gRPC API will still be supported for some time, most likely until v8 in 2026, but will be eventually removed in favor of REST API.
+// Deprecated: The gRPC API will remain the default and fully supported through v8 (expected in 2026) but will be eventually removed in favor of REST API.
 //
 // ListValidatorAssignments retrieves the validator assignments for a given epoch,
 // optional validator indices or public keys may be included to filter validator assignments.

beacon-chain/rpc/prysm/v1alpha1/beacon/attestations.go

@@ -49,7 +49,7 @@ func mapAttestationsByTargetRoot(atts []ethpb.Att) map[[32]byte][]ethpb.Att {
 	return attsMap
 }
 
-// Deprecated: gRPC API will still be supported for some time, most likely until v8 in 2026, but will be eventually removed in favor of REST API.
+// Deprecated: The gRPC API will remain the default and fully supported through v8 (expected in 2026) but will be eventually removed in favor of REST API.
 //
 // ListAttestations retrieves attestations by block root, slot, or epoch.
 // Attestations are sorted by data slot by default.
@@ -115,7 +115,7 @@ func (bs *Server) ListAttestations(
 	}, nil
 }
 
-// Deprecated: gRPC API will still be supported for some time, most likely until v8 in 2026, but will be eventually removed in favor of REST API.
+// Deprecated: The gRPC API will remain the default and fully supported through v8 (expected in 2026) but will be eventually removed in favor of REST API.
 //
 // ListAttestationsElectra retrieves attestations by block root, slot, or epoch.
 // Attestations are sorted by data slot by default.
@@ -180,7 +180,7 @@ func (bs *Server) ListAttestationsElectra(ctx context.Context, req *ethpb.ListAt
 	}, nil
 }
 
-// Deprecated: gRPC API will still be supported for some time, most likely until v8 in 2026, but will be eventually removed in favor of REST API.
+// Deprecated: The gRPC API will remain the default and fully supported through v8 (expected in 2026) but will be eventually removed in favor of REST API.
 //
 // ListIndexedAttestations retrieves indexed attestations by block root.
 // IndexedAttestationsForEpoch are sorted by data slot by default. Start-end epoch
@@ -242,7 +242,7 @@ func (bs *Server) ListIndexedAttestations(
 	}, nil
 }
 
-// Deprecated: gRPC API will still be supported for some time, most likely until v8 in 2026, but will be eventually removed in favor of REST API.
+// Deprecated: The gRPC API will remain the default and fully supported through v8 (expected in 2026) but will be eventually removed in favor of REST API.
 //
 // ListIndexedAttestationsElectra retrieves indexed attestations by block root.
 // IndexedAttestationsForEpoch are sorted by data slot by default. Start-end epoch
@@ -305,7 +305,7 @@ func (bs *Server) ListIndexedAttestationsElectra(
 	}, nil
 }
 
-// Deprecated: gRPC API will still be supported for some time, most likely until v8 in 2026, but will be eventually removed in favor of REST API.
+// Deprecated: The gRPC API will remain the default and fully supported through v8 (expected in 2026) but will be eventually removed in favor of REST API.
 //
 // AttestationPool retrieves pending attestations.
 //
@@ -350,7 +350,7 @@ func (bs *Server) AttestationPool(_ context.Context, req *ethpb.AttestationPoolR
 	}, nil
 }
 
-// Deprecated: gRPC API will still be supported for some time, most likely until v8 in 2026, but will be eventually removed in favor of REST API.
+// Deprecated: The gRPC API will remain the default and fully supported through v8 (expected in 2026) but will be eventually removed in favor of REST API.
 func (bs *Server) AttestationPoolElectra(_ context.Context, req *ethpb.AttestationPoolRequest) (*ethpb.AttestationPoolElectraResponse, error) {
 	var atts []*ethpb.AttestationElectra
 	var err error

beacon-chain/rpc/prysm/v1alpha1/beacon/blocks.go

@@ -26,7 +26,7 @@ type blockContainer struct {
 	isCanonical bool
 }
 
-// Deprecated: gRPC API will still be supported for some time, most likely until v8 in 2026, but will be eventually removed in favor of REST API.
+// Deprecated: The gRPC API will remain the default and fully supported through v8 (expected in 2026) but will be eventually removed in favor of REST API.
 //
 // ListBeaconBlocks retrieves blocks by root, slot, or epoch.
 //
@@ -246,7 +246,7 @@ func (bs *Server) listBlocksForGenesis(ctx context.Context, _ *ethpb.ListBlocksR
 	}}, 1, strconv.Itoa(0), nil
 }
 
-// Deprecated: gRPC API will still be supported for some time, most likely until v8 in 2026, but will be eventually removed in favor of REST API.
+// Deprecated: The gRPC API will remain the default and fully supported through v8 (expected in 2026) but will be eventually removed in favor of REST API.
 //
 // GetChainHead retrieves information about the head of the beacon chain from
 // the view of the beacon chain node.

beacon-chain/rpc/prysm/v1alpha1/beacon/committees.go

@@ -15,7 +15,7 @@ import (
 	"google.golang.org/grpc/status"
 )
 
-// Deprecated: gRPC API will still be supported for some time, most likely until v8 in 2026, but will be eventually removed in favor of REST API.
+// Deprecated: The gRPC API will remain the default and fully supported through v8 (expected in 2026) but will be eventually removed in favor of REST API.
 //
 // ListBeaconCommittees for a given epoch.
 //

beacon-chain/rpc/prysm/v1alpha1/beacon/config.go

@@ -10,7 +10,7 @@ import (
 	"google.golang.org/protobuf/types/known/emptypb"
 )
 
-// Deprecated: gRPC API will still be supported for some time, most likely until v8 in 2026, but will be eventually removed in favor of REST API.
+// Deprecated: The gRPC API will remain the default and fully supported through v8 (expected in 2026) but will be eventually removed in favor of REST API.
 //
 // GetBeaconConfig retrieves the current configuration parameters of the beacon chain.
 func (_ *Server) GetBeaconConfig(_ context.Context, _ *emptypb.Empty) (*ethpb.BeaconConfig, error) {

beacon-chain/rpc/prysm/v1alpha1/beacon/slashings.go

@@ -11,7 +11,7 @@ import (
 	"google.golang.org/grpc/status"
 )
 
-// Deprecated: gRPC API will still be supported for some time, most likely until v8 in 2026, but will be eventually removed in favor of REST API.
+// Deprecated: The gRPC API will remain the default and fully supported through v8 (expected in 2026) but will be eventually removed in favor of REST API.
 //
 // SubmitProposerSlashing receives a proposer slashing object via
 // RPC and injects it into the beacon node's operations pool.
@@ -38,12 +38,12 @@ func (bs *Server) SubmitProposerSlashing(
 	}, nil
 }
 
-// Deprecated: gRPC API will still be supported for some time, most likely until v8 in 2026, but will be eventually removed in favor of REST API.
+// Deprecated: The gRPC API will remain the default and fully supported through v8 (expected in 2026) but will be eventually removed in favor of REST API.
 func (bs *Server) SubmitAttesterSlashing(ctx context.Context, req *ethpb.AttesterSlashing) (*ethpb.SubmitSlashingResponse, error) {
 	return bs.submitAttesterSlashing(ctx, req)
 }
 
-// Deprecated: gRPC API will still be supported for some time, most likely until v8 in 2026, but will be eventually removed in favor of REST API.
+// Deprecated: The gRPC API will remain the default and fully supported through v8 (expected in 2026) but will be eventually removed in favor of REST API.
 //
 // SubmitAttesterSlashingElectra receives an attester slashing object via
 // RPC and injects it into the beacon node's operations pool.

beacon-chain/rpc/prysm/v1alpha1/beacon/validators.go

@@ -24,7 +24,7 @@ import (
 	"google.golang.org/protobuf/types/known/emptypb"
 )
 
-// Deprecated: gRPC API will still be supported for some time, most likely until v8 in 2026, but will be eventually removed in favor of REST API.
+// Deprecated: The gRPC API will remain the default and fully supported through v8 (expected in 2026) but will be eventually removed in favor of REST API.
 //
 // ListValidatorBalances retrieves the validator balances for a given set of public keys.
 // An optional Epoch parameter is provided to request historical validator balances from
@@ -182,7 +182,7 @@ func (bs *Server) ListValidatorBalances(
 	}, nil
 }
 
-// Deprecated: gRPC API will still be supported for some time, most likely until v8 in 2026, but will be eventually removed in favor of REST API.
+// Deprecated: The gRPC API will remain the default and fully supported through v8 (expected in 2026) but will be eventually removed in favor of REST API.
 //
 // ListValidators retrieves the current list of active validators with an optional historical epoch flag to
 // retrieve validator set in time.
@@ -342,7 +342,7 @@ func (bs *Server) ListValidators(
 	}, nil
 }
 
-// Deprecated: gRPC API will still be supported for some time, most likely until v8 in 2026, but will be eventually removed in favor of REST API.
+// Deprecated: The gRPC API will remain the default and fully supported through v8 (expected in 2026) but will be eventually removed in favor of REST API.
 //
 // GetValidator information from any validator in the registry by index or public key.
 func (bs *Server) GetValidator(
@@ -388,7 +388,7 @@ func (bs *Server) GetValidator(
 	return nil, status.Error(codes.NotFound, "No validator matched filter criteria")
 }
 
-// Deprecated: gRPC API will still be supported for some time, most likely until v8 in 2026, but will be eventually removed in favor of REST API.
+// Deprecated: The gRPC API will remain the default and fully supported through v8 (expected in 2026) but will be eventually removed in favor of REST API.
 //
 // GetValidatorActiveSetChanges retrieves the active set changes for a given epoch.
 //
@@ -416,7 +416,7 @@ func (bs *Server) GetValidatorActiveSetChanges(
 	return as, nil
 }
 
-// Deprecated: gRPC API will still be supported for some time, most likely until v8 in 2026, but will be eventually removed in favor of REST API.
+// Deprecated: The gRPC API will remain the default and fully supported through v8 (expected in 2026) but will be eventually removed in favor of REST API.
 //
 // GetValidatorParticipation retrieves the validator participation information for a given epoch,
 // it returns the information about validator's participation rate in voting on the proof of stake
@@ -443,7 +443,7 @@ func (bs *Server) GetValidatorParticipation(
 	return vp, nil
 }
 
-// Deprecated: gRPC API will still be supported for some time, most likely until v8 in 2026, but will be eventually removed in favor of REST API.
+// Deprecated: The gRPC API will remain the default and fully supported through v8 (expected in 2026) but will be eventually removed in favor of REST API.
 //
 // GetValidatorQueue retrieves the current validator queue information.
 func (bs *Server) GetValidatorQueue(
@@ -536,7 +536,7 @@ func (bs *Server) GetValidatorQueue(
 	}, nil
 }
 
-// Deprecated: gRPC API will still be supported for some time, most likely until v8 in 2026, but will be eventually removed in favor of REST API.
+// Deprecated: The gRPC API will remain the default and fully supported through v8 (expected in 2026) but will be eventually removed in favor of REST API.
 //
 // GetValidatorPerformance reports the validator's latest balance along with other important metrics on
 // rewards and penalties throughout its lifecycle in the beacon chain.
@@ -550,7 +550,7 @@ func (bs *Server) GetValidatorPerformance(
 	return response, nil
 }
 
-// Deprecated: gRPC API will still be supported for some time, most likely until v8 in 2026, but will be eventually removed in favor of REST API.
+// Deprecated: The gRPC API will remain the default and fully supported through v8 (expected in 2026) but will be eventually removed in favor of REST API.
 //
 // GetIndividualVotes retrieves individual voting status of validators.
 func (bs *Server) GetIndividualVotes(

beacon-chain/rpc/prysm/v1alpha1/debug/block.go

@@ -17,7 +17,7 @@ import (
 	"google.golang.org/grpc/status"
 )
 
-// Deprecated: gRPC API will still be supported for some time, most likely until v8 in 2026, but will be eventually removed in favor of REST API.
+// Deprecated: The gRPC API will remain the default and fully supported through v8 (expected in 2026) but will be eventually removed in favor of REST API.
 //
 // GetBlock in an ssz-encoded format by block root.
 func (ds *Server) GetBlock(
@@ -41,7 +41,7 @@ func (ds *Server) GetBlock(
 	}, nil
 }
 
-// Deprecated: gRPC API will still be supported for some time, most likely until v8 in 2026, but will be eventually removed in favor of REST API.
+// Deprecated: The gRPC API will remain the default and fully supported through v8 (expected in 2026) but will be eventually removed in favor of REST API.
 //
 // GetInclusionSlot of an attestation in block.
 func (ds *Server) GetInclusionSlot(ctx context.Context, req *pbrpc.InclusionSlotRequest) (*pbrpc.InclusionSlotResponse, error) {

beacon-chain/rpc/prysm/v1alpha1/debug/p2p.go

@@ -13,7 +13,7 @@ import (
 	"google.golang.org/grpc/status"
 )
 
-// Deprecated: gRPC API will still be supported for some time, most likely until v8 in 2026, but will be eventually removed in favor of REST API.
+// Deprecated: The gRPC API will remain the default and fully supported through v8 (expected in 2026) but will be eventually removed in favor of REST API.
 //
 // GetPeer returns the data known about the peer defined by the provided peer id.
 func (ds *Server) GetPeer(_ context.Context, peerReq *ethpb.PeerRequest) (*ethpb.DebugPeerResponse, error) {
@@ -24,7 +24,7 @@ func (ds *Server) GetPeer(_ context.Context, peerReq *ethpb.PeerRequest) (*ethpb
 	return ds.getPeer(pid)
 }
 
-// Deprecated: gRPC API will still be supported for some time, most likely until v8 in 2026, but will be eventually removed in favor of REST API.
+// Deprecated: The gRPC API will remain the default and fully supported through v8 (expected in 2026) but will be eventually removed in favor of REST API.
 //
 // ListPeers returns all peers known to the host node, regardless of if they are connected/
 // disconnected.

beacon-chain/rpc/prysm/v1alpha1/debug/state.go

@@ -10,7 +10,7 @@ import (
 	"google.golang.org/grpc/status"
 )
 
-// Deprecated: gRPC API will still be supported for some time, most likely until v8 in 2026, but will be eventually removed in favor of REST API.
+// Deprecated: The gRPC API will remain the default and fully supported through v8 (expected in 2026) but will be eventually removed in favor of REST API.
 //
 // GetBeaconState retrieves an ssz-encoded beacon state
 // from the beacon node by either a slot or block root.

beacon-chain/rpc/prysm/v1alpha1/node/server.go

@@ -49,7 +49,7 @@ type Server struct {
 	BeaconMonitoringPort int
 }
 
-// Deprecated: gRPC API will still be supported for some time, most likely until v8 in 2026, but will be eventually removed in favor of REST API.
+// Deprecated: The gRPC API will remain the default and fully supported through v8 (expected in 2026) but will be eventually removed in favor of REST API.
 //
 // GetHealth checks the health of the node
 func (ns *Server) GetHealth(ctx context.Context, request *ethpb.HealthRequest) (*empty.Empty, error) {
@@ -80,7 +80,7 @@ func (ns *Server) GetHealth(ctx context.Context, request *ethpb.HealthRequest) (
 	return &empty.Empty{}, status.Errorf(codes.Unavailable, "service unavailable")
 }
 
-// Deprecated: gRPC API will still be supported for some time, most likely until v8 in 2026, but will be eventually removed in favor of REST API.
+// Deprecated: The gRPC API will remain the default and fully supported through v8 (expected in 2026) but will be eventually removed in favor of REST API.
 //
 // GetSyncStatus checks the current network sync status of the node.
 func (ns *Server) GetSyncStatus(_ context.Context, _ *empty.Empty) (*ethpb.SyncStatus, error) {
@@ -89,7 +89,7 @@ func (ns *Server) GetSyncStatus(_ context.Context, _ *empty.Empty) (*ethpb.SyncS
 	}, nil
 }
 
-// Deprecated: gRPC API will still be supported for some time, most likely until v8 in 2026, but will be eventually removed in favor of REST API.
+// Deprecated: The gRPC API will remain the default and fully supported through v8 (expected in 2026) but will be eventually removed in favor of REST API.
 //
 // GetGenesis fetches genesis chain information of Ethereum. Returns unix timestamp 0
 // if a genesis time has yet to be determined.
@@ -115,7 +115,7 @@ func (ns *Server) GetGenesis(ctx context.Context, _ *empty.Empty) (*ethpb.Genesi
 	}, nil
 }
 
-// Deprecated: gRPC API will still be supported for some time, most likely until v8 in 2026, but will be eventually removed in favor of REST API.
+// Deprecated: The gRPC API will remain the default and fully supported through v8 (expected in 2026) but will be eventually removed in favor of REST API.
 //
 // GetVersion checks the version information of the beacon node.
 func (_ *Server) GetVersion(_ context.Context, _ *empty.Empty) (*ethpb.Version, error) {
@@ -124,7 +124,7 @@ func (_ *Server) GetVersion(_ context.Context, _ *empty.Empty) (*ethpb.Version,
 	}, nil
 }
 
-// Deprecated: gRPC API will still be supported for some time, most likely until v8 in 2026, but will be eventually removed in favor of REST API.
+// Deprecated: The gRPC API will remain the default and fully supported through v8 (expected in 2026) but will be eventually removed in favor of REST API.
 //
 // ListImplementedServices lists the services implemented and enabled by this node.
 //
@@ -143,7 +143,7 @@ func (ns *Server) ListImplementedServices(_ context.Context, _ *empty.Empty) (*e
 	}, nil
 }
 
-// Deprecated: gRPC API will still be supported for some time, most likely until v8 in 2026, but will be eventually removed in favor of REST API.
+// Deprecated: The gRPC API will remain the default and fully supported through v8 (expected in 2026) but will be eventually removed in favor of REST API.
 //
 // GetHost returns the p2p data on the current local and host peer.
 func (ns *Server) GetHost(_ context.Context, _ *empty.Empty) (*ethpb.HostData, error) {
@@ -168,7 +168,7 @@ func (ns *Server) GetHost(_ context.Context, _ *empty.Empty) (*ethpb.HostData, e
 	}, nil
 }
 
-// Deprecated: gRPC API will still be supported for some time, most likely until v8 in 2026, but will be eventually removed in favor of REST API.
+// Deprecated: The gRPC API will remain the default and fully supported through v8 (expected in 2026) but will be eventually removed in favor of REST API.
 //
 // GetPeer returns the data known about the peer defined by the provided peer id.
 func (ns *Server) GetPeer(_ context.Context, peerReq *ethpb.PeerRequest) (*ethpb.Peer, error) {
@@ -215,7 +215,7 @@ func (ns *Server) GetPeer(_ context.Context, peerReq *ethpb.PeerRequest) (*ethpb
 	}, nil
 }
 
-// Deprecated: gRPC API will still be supported for some time, most likely until v8 in 2026, but will be eventually removed in favor of REST API.
+// Deprecated: The gRPC API will remain the default and fully supported through v8 (expected in 2026) but will be eventually removed in favor of REST API.
 //
 // ListPeers lists the peers connected to this node.
 func (ns *Server) ListPeers(ctx context.Context, _ *empty.Empty) (*ethpb.Peers, error) {
@@ -270,7 +270,7 @@ func (ns *Server) ListPeers(ctx context.Context, _ *empty.Empty) (*ethpb.Peers,
 	}, nil
 }
 
-// Deprecated: gRPC API will still be supported for some time, most likely until v8 in 2026, but will be eventually removed in favor of REST API.
+// Deprecated: The gRPC API will remain the default and fully supported through v8 (expected in 2026) but will be eventually removed in favor of REST API.
 //
 // GetETH1ConnectionStatus gets data about the ETH1 endpoints.
 func (ns *Server) GetETH1ConnectionStatus(_ context.Context, _ *empty.Empty) (*ethpb.ETH1ConnectionStatus, error) {
@@ -286,7 +286,7 @@ func (ns *Server) GetETH1ConnectionStatus(_ context.Context, _ *empty.Empty) (*e
 	}, nil
 }
 
-// Deprecated: gRPC API will still be supported for some time, most likely until v8 in 2026, but will be eventually removed in favor of REST API.
+// Deprecated: The gRPC API will remain the default and fully supported through v8 (expected in 2026) but will be eventually removed in favor of REST API.
 //
 // StreamBeaconLogs from the beacon node via a gRPC server-side stream.
 // DEPRECATED: This endpoint doesn't appear to be used and have been marked for deprecation.

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

@@ -17,7 +17,7 @@ import (
 	"google.golang.org/grpc/status"
 )
 
-// Deprecated: gRPC API will still be supported for some time, most likely until v8 in 2026, but will be eventually removed in favor of REST API.
+// Deprecated: The gRPC API will remain the default and fully supported through v8 (expected in 2026) but will be eventually removed in favor of REST API.
 //
 // SubmitAggregateSelectionProof is called by a validator when its assigned to be an aggregator.
 // The aggregator submits the selection proof to obtain the aggregated attestation
@@ -55,7 +55,7 @@ func (vs *Server) SubmitAggregateSelectionProof(ctx context.Context, req *ethpb.
 	return &ethpb.AggregateSelectionResponse{AggregateAndProof: attAndProof}, nil
 }
 
-// Deprecated: gRPC API will still be supported for some time, most likely until v8 in 2026, but will be eventually removed in favor of REST API.
+// Deprecated: The gRPC API will remain the default and fully supported through v8 (expected in 2026) but will be eventually removed in favor of REST API.
 //
 // SubmitAggregateSelectionProofElectra is called by a validator when its assigned to be an aggregator.
 // The aggregator submits the selection proof to obtain the aggregated attestation
@@ -149,7 +149,7 @@ func (vs *Server) processAggregateSelection(ctx context.Context, req *ethpb.Aggr
 	return indexInCommittee, validatorIndex, nil
 }
 
-// Deprecated: gRPC API will still be supported for some time, most likely until v8 in 2026, but will be eventually removed in favor of REST API.
+// Deprecated: The gRPC API will remain the default and fully supported through v8 (expected in 2026) but will be eventually removed in favor of REST API.
 //
 // SubmitSignedAggregateSelectionProof is called by a validator to broadcast a signed
 // aggregated and proof object.
@@ -163,7 +163,7 @@ func (vs *Server) SubmitSignedAggregateSelectionProof(
 	return &ethpb.SignedAggregateSubmitResponse{}, nil
 }
 
-// Deprecated: gRPC API will still be supported for some time, most likely until v8 in 2026, but will be eventually removed in favor of REST API.
+// Deprecated: The gRPC API will remain the default and fully supported through v8 (expected in 2026) but will be eventually removed in favor of REST API.
 //
 // SubmitSignedAggregateSelectionProofElectra is called by a validator to broadcast a signed
 // aggregated and proof object.

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

@@ -22,7 +22,7 @@ import (
 	"google.golang.org/protobuf/types/known/emptypb"
 )
 
-// Deprecated: gRPC API will still be supported for some time, most likely until v8 in 2026, but will be eventually removed in favor of REST API.
+// Deprecated: The gRPC API will remain the default and fully supported through v8 (expected in 2026) but will be eventually removed in favor of REST API.
 //
 // GetAttestationData requests that the beacon node produce an attestation data object,
 // which the validator acting as an attester will then sign.
@@ -44,7 +44,7 @@ func (vs *Server) GetAttestationData(ctx context.Context, req *ethpb.Attestation
 	return res, nil
 }
 
-// Deprecated: gRPC API will still be supported for some time, most likely until v8 in 2026, but will be eventually removed in favor of REST API.
+// Deprecated: The gRPC API will remain the default and fully supported through v8 (expected in 2026) but will be eventually removed in favor of REST API.
 //
 // ProposeAttestation is a function called by an attester to vote
 // on a block via an attestation object as defined in the Ethereum specification.
@@ -74,7 +74,7 @@ func (vs *Server) ProposeAttestation(ctx context.Context, att *ethpb.Attestation
 	return resp, nil
 }
 
-// Deprecated: gRPC API will still be supported for some time, most likely until v8 in 2026, but will be eventually removed in favor of REST API.
+// Deprecated: The gRPC API will remain the default and fully supported through v8 (expected in 2026) but will be eventually removed in favor of REST API.
 //
 // ProposeAttestationElectra is a function called by an attester to vote
 // on a block via an attestation object as defined in the Ethereum specification.
@@ -114,7 +114,7 @@ func (vs *Server) ProposeAttestationElectra(ctx context.Context, singleAtt *ethp
 	return resp, nil
 }
 
-// Deprecated: gRPC API will still be supported for some time, most likely until v8 in 2026, but will be eventually removed in favor of REST API.
+// Deprecated: The gRPC API will remain the default and fully supported through v8 (expected in 2026) but will be eventually removed in favor of REST API.
 //
 // SubscribeCommitteeSubnets subscribes to the committee ID subnet given subscribe request.
 func (vs *Server) SubscribeCommitteeSubnets(ctx context.Context, req *ethpb.CommitteeSubnetsSubscribeRequest) (*emptypb.Empty, error) {

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

@@ -82,7 +82,7 @@ func TestProposeAttestation(t *testing.T) {
 		config := params.BeaconConfig()
 		config.ElectraForkEpoch = 0
 		params.OverrideBeaconConfig(config)
-		
+
 		state, err := util.NewBeaconState()
 		require.NoError(t, err)
 		require.NoError(t, state.SetSlot(params.BeaconConfig().SlotsPerEpoch+1))

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

@@ -9,13 +9,12 @@ import (
 	"github.com/OffchainLabs/prysm/v6/consensus-types/primitives"
 	ethpb "github.com/OffchainLabs/prysm/v6/proto/prysm/v1alpha1"
 	"github.com/OffchainLabs/prysm/v6/runtime/version"
-	"github.com/OffchainLabs/prysm/v6/time/slots"
 	"github.com/pkg/errors"
 	"google.golang.org/grpc/codes"
 	"google.golang.org/grpc/status"
 )
 
-// Deprecated: gRPC API will still be supported for some time, most likely until v8 in 2026, but will be eventually removed in favor of REST API.
+// Deprecated: The gRPC API will remain the default and fully supported through v8 (expected in 2026) but will be eventually removed in favor of REST API.
 //
 // StreamBlocksAltair to clients every single time a block is received by the beacon node.
 func (vs *Server) StreamBlocksAltair(req *ethpb.StreamBlocksRequest, stream ethpb.BeaconNodeValidator_StreamBlocksAltairServer) error {
@@ -50,7 +49,7 @@ func (vs *Server) StreamBlocksAltair(req *ethpb.StreamBlocksRequest, stream ethp
 	}
 }
 
-// Deprecated: gRPC API will still be supported for some time, most likely until v8 in 2026, but will be eventually removed in favor of REST API.
+// Deprecated: The gRPC API will remain the default and fully supported through v8 (expected in 2026) but will be eventually removed in favor of REST API.
 //
 // StreamSlots sends a the block's slot and dependent roots to clients every single time a block is received by the beacon node.
 func (vs *Server) StreamSlots(req *ethpb.StreamSlotsRequest, stream ethpb.BeaconNodeValidator_StreamSlotsServer) error {
@@ -67,6 +66,7 @@ func (vs *Server) StreamSlots(req *ethpb.StreamSlotsRequest, stream ethpb.Beacon
 		select {
 		case ev := <-ch:
 			var s primitives.Slot
+			var currDependentRoot, prevDependentRoot [32]byte
 			if req.VerifiedOnly {
 				if ev.Type != statefeed.BlockProcessed {
 					continue
@@ -76,6 +76,8 @@ func (vs *Server) StreamSlots(req *ethpb.StreamSlotsRequest, stream ethpb.Beacon
 					continue
 				}
 				s = data.Slot
+				currDependentRoot = data.CurrDependentRoot
+				prevDependentRoot = data.PrevDependentRoot
 			} else {
 				if ev.Type != blockfeed.ReceivedBlock {
 					continue
@@ -85,24 +87,14 @@ func (vs *Server) StreamSlots(req *ethpb.StreamSlotsRequest, stream ethpb.Beacon
 					continue
 				}
 				s = data.SignedBlock.Block().Slot()
-			}
-			currEpoch := slots.ToEpoch(s)
-			currDepRoot, err := vs.ForkchoiceFetcher.DependentRoot(currEpoch)
-			if err != nil {
-				return status.Errorf(codes.Internal, "Could not get dependent root: %v", err)
-			}
-			prevDepRoot := currDepRoot
-			if currEpoch > 0 {
-				prevDepRoot, err = vs.ForkchoiceFetcher.DependentRoot(currEpoch - 1)
-				if err != nil {
-					return status.Errorf(codes.Internal, "Could not get dependent root: %v", err)
-				}
+				currDependentRoot = data.CurrDependentRoot
+				prevDependentRoot = data.PrevDependentRoot
 			}
 			if err := stream.Send(
 				&ethpb.StreamSlotsResponse{
 					Slot:                      s,
-					PreviousDutyDependentRoot: prevDepRoot[:],
-					CurrentDutyDependentRoot:  currDepRoot[:],
+					PreviousDutyDependentRoot: prevDependentRoot[:],
+					CurrentDutyDependentRoot:  currDependentRoot[:],
 				}); err != nil {
 				return status.Errorf(codes.Unavailable, "Could not send over stream: %v", err)
 			}

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

@@ -16,7 +16,7 @@ import (
 	"google.golang.org/protobuf/types/known/emptypb"
 )
 
-// Deprecated: gRPC API will still be supported for some time, most likely until v8 in 2026, but will be eventually removed in favor of REST API.
+// Deprecated: The gRPC API will remain the default and fully supported through v8 (expected in 2026) but will be eventually removed in favor of REST API.
 //
 // GetDuties returns the duties assigned to a list of validators specified
 // in the request object.
@@ -178,7 +178,7 @@ func (vs *Server) duties(ctx context.Context, req *ethpb.DutiesRequest) (*ethpb.
 	}, nil
 }
 
-// Deprecated: gRPC API will still be supported for some time, most likely until v8 in 2026, but will be eventually removed in favor of REST API.
+// Deprecated: The gRPC API will remain the default and fully supported through v8 (expected in 2026) but will be eventually removed in favor of REST API.
 //
 // AssignValidatorToSubnet checks the status and pubkey of a particular validator
 // to discern whether persistent subnets need to be registered for them.

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

@@ -12,7 +12,7 @@ import (
 	"google.golang.org/grpc/status"
 )
 
-// Deprecated: gRPC API will still be supported for some time, most likely until v8 in 2026, but will be eventually removed in favor of REST API.
+// Deprecated: The gRPC API will remain the default and fully supported through v8 (expected in 2026) but will be eventually removed in favor of REST API.
 //
 // ProposeExit proposes an exit for a validator.
 func (vs *Server) ProposeExit(ctx context.Context, req *ethpb.SignedVoluntaryExit) (*ethpb.ProposeExitResponse, error) {

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

@@ -49,7 +49,7 @@ const (
 	defaultBuilderBoostFactor = primitives.Gwei(100)
 )
 
-// Deprecated: gRPC API will still be supported for some time, most likely until v8 in 2026, but will be eventually removed in favor of REST API.
+// Deprecated: The gRPC API will remain the default and fully supported through v8 (expected in 2026) but will be eventually removed in favor of REST API.
 //
 // GetBeaconBlock is called by a proposer during its assigned slot to request a block to sign
 // by passing in the slot and the signed randao reveal of the slot.
@@ -279,7 +279,7 @@ func (vs *Server) BuildBlockParallel(ctx context.Context, sBlk interfaces.Signed
 	return vs.constructGenericBeaconBlock(sBlk, bundle, winningBid)
 }
 
-// Deprecated: gRPC API will still be supported for some time, most likely until v8 in 2026, but will be eventually removed in favor of REST API.
+// Deprecated: The gRPC API will remain the default and fully supported through v8 (expected in 2026) but will be eventually removed in favor of REST API.
 //
 // ProposeBeaconBlock handles the proposal of beacon blocks.
 // TODO: Add tests
@@ -525,7 +525,7 @@ func (vs *Server) broadcastAndReceiveDataColumns(
 	return nil
 }
 
-// Deprecated: gRPC API will still be supported for some time, most likely until v8 in 2026, but will be eventually removed in favor of REST API.
+// Deprecated: The gRPC API will remain the default and fully supported through v8 (expected in 2026) but will be eventually removed in favor of REST API.
 //
 // PrepareBeaconProposer caches and updates the fee recipient for the given proposer.
 func (vs *Server) PrepareBeaconProposer(
@@ -562,7 +562,7 @@ func (vs *Server) PrepareBeaconProposer(
 	return &emptypb.Empty{}, nil
 }
 
-// Deprecated: gRPC API will still be supported for some time, most likely until v8 in 2026, but will be eventually removed in favor of REST API.
+// Deprecated: The gRPC API will remain the default and fully supported through v8 (expected in 2026) but will be eventually removed in favor of REST API.
 //
 // GetFeeRecipientByPubKey returns a fee recipient from the beacon node's settings or db based on a given public key
 func (vs *Server) GetFeeRecipientByPubKey(ctx context.Context, request *ethpb.FeeRecipientByPubKeyRequest) (*ethpb.FeeRecipientByPubKeyResponse, error) {
@@ -619,7 +619,7 @@ func (vs *Server) computeStateRoot(ctx context.Context, block interfaces.ReadOnl
 	return root[:], nil
 }
 
-// Deprecated: gRPC API will still be supported for some time, most likely until v8 in 2026, but will be eventually removed in favor of REST API.
+// Deprecated: The gRPC API will remain the default and fully supported through v8 (expected in 2026) but will be eventually removed in favor of REST API.
 //
 // SubmitValidatorRegistrations submits validator registrations.
 func (vs *Server) SubmitValidatorRegistrations(ctx context.Context, reg *ethpb.SignedValidatorRegistrationsV1) (*emptypb.Empty, error) {

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

@@ -83,7 +83,7 @@ type Server struct {
 	AttestationStateFetcher blockchain.AttestationStateFetcher
 }
 
-// Deprecated: gRPC API will still be supported for some time, most likely until v8 in 2026, but will be eventually removed in favor of REST API.
+// Deprecated: The gRPC API will remain the default and fully supported through v8 (expected in 2026) but will be eventually removed in favor of REST API.
 //
 // WaitForActivation checks if a validator public key exists in the active validator registry of the current
 // beacon state, if not, then it creates a stream which listens for canonical states which contain
@@ -133,7 +133,7 @@ func (vs *Server) WaitForActivation(req *ethpb.ValidatorActivationRequest, strea
 	}
 }
 
-// Deprecated: gRPC API will still be supported for some time, most likely until v8 in 2026, but will be eventually removed in favor of REST API.
+// Deprecated: The gRPC API will remain the default and fully supported through v8 (expected in 2026) but will be eventually removed in favor of REST API.
 //
 // ValidatorIndex is called by a validator to get its index location in the beacon state.
 func (vs *Server) ValidatorIndex(ctx context.Context, req *ethpb.ValidatorIndexRequest) (*ethpb.ValidatorIndexResponse, error) {
@@ -152,7 +152,7 @@ func (vs *Server) ValidatorIndex(ctx context.Context, req *ethpb.ValidatorIndexR
 	return &ethpb.ValidatorIndexResponse{Index: index}, nil
 }
 
-// Deprecated: gRPC API will still be supported for some time, most likely until v8 in 2026, but will be eventually removed in favor of REST API.
+// Deprecated: The gRPC API will remain the default and fully supported through v8 (expected in 2026) but will be eventually removed in favor of REST API.
 //
 // DomainData fetches the current domain version information from the beacon state.
 func (vs *Server) DomainData(ctx context.Context, request *ethpb.DomainRequest) (*ethpb.DomainResponse, error) {
@@ -184,7 +184,7 @@ func (vs *Server) DomainData(ctx context.Context, request *ethpb.DomainRequest)
 	}, nil
 }
 
-// Deprecated: gRPC API will still be supported for some time, most likely until v8 in 2026, but will be eventually removed in favor of REST API.
+// Deprecated: The gRPC API will remain the default and fully supported through v8 (expected in 2026) but will be eventually removed in favor of REST API.
 //
 // WaitForChainStart queries the logs of the Deposit Contract in order to verify the beacon chain
 // has started its runtime and validators begin their responsibilities. If it has not, it then

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

@@ -29,7 +29,7 @@ var nonExistentIndex = primitives.ValidatorIndex(^uint64(0))
 
 var errParticipation = status.Errorf(codes.Internal, "Failed to obtain epoch participation")
 
-// Deprecated: gRPC API will still be supported for some time, most likely until v8 in 2026, but will be eventually removed in favor of REST API.
+// Deprecated: The gRPC API will remain the default and fully supported through v8 (expected in 2026) but will be eventually removed in favor of REST API.
 //
 // ValidatorStatus returns the validator status of the current epoch.
 // The status response can be one of the following:
@@ -54,7 +54,7 @@ func (vs *Server) ValidatorStatus(
 	return vStatus, nil
 }
 
-// Deprecated: gRPC API will still be supported for some time, most likely until v8 in 2026, but will be eventually removed in favor of REST API.
+// Deprecated: The gRPC API will remain the default and fully supported through v8 (expected in 2026) but will be eventually removed in favor of REST API.
 //
 // MultipleValidatorStatus is the same as ValidatorStatus. Supports retrieval of multiple
 // validator statuses. Takes a list of public keys or a list of validator indices.
@@ -104,7 +104,7 @@ func (vs *Server) MultipleValidatorStatus(
 	}, nil
 }
 
-// Deprecated: gRPC API will still be supported for some time, most likely until v8 in 2026, but will be eventually removed in favor of REST API.
+// Deprecated: The gRPC API will remain the default and fully supported through v8 (expected in 2026) but will be eventually removed in favor of REST API.
 //
 // CheckDoppelGanger checks if the provided keys are currently active in the network.
 func (vs *Server) CheckDoppelGanger(ctx context.Context, req *ethpb.DoppelGangerRequest) (*ethpb.DoppelGangerResponse, error) {

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

@@ -12,7 +12,7 @@ import (
 	"google.golang.org/protobuf/types/known/emptypb"
 )
 
-// Deprecated: gRPC API will still be supported for some time, most likely until v8 in 2026, but will be eventually removed in favor of REST API.
+// Deprecated: The gRPC API will remain the default and fully supported through v8 (expected in 2026) but will be eventually removed in favor of REST API.
 //
 // GetSyncMessageBlockRoot retrieves the sync committee block root of the beacon chain.
 func (vs *Server) GetSyncMessageBlockRoot(
@@ -34,7 +34,7 @@ func (vs *Server) GetSyncMessageBlockRoot(
 	}, nil
 }
 
-// Deprecated: gRPC API will still be supported for some time, most likely until v8 in 2026, but will be eventually removed in favor of REST API.
+// Deprecated: The gRPC API will remain the default and fully supported through v8 (expected in 2026) but will be eventually removed in favor of REST API.
 //
 // SubmitSyncMessage submits the sync committee message to the network.
 // It also saves the sync committee message into the pending pool for block inclusion.
@@ -45,7 +45,7 @@ func (vs *Server) SubmitSyncMessage(ctx context.Context, msg *ethpb.SyncCommitte
 	return &emptypb.Empty{}, nil
 }
 
-// Deprecated: gRPC API will still be supported for some time, most likely until v8 in 2026, but will be eventually removed in favor of REST API.
+// Deprecated: The gRPC API will remain the default and fully supported through v8 (expected in 2026) but will be eventually removed in favor of REST API.
 //
 // GetSyncSubcommitteeIndex is called by a sync committee participant to get
 // its subcommittee index for sync message aggregation duty.
@@ -63,7 +63,7 @@ func (vs *Server) GetSyncSubcommitteeIndex(
 	return &ethpb.SyncSubcommitteeIndexResponse{Indices: indices}, nil
 }
 
-// Deprecated: gRPC API will still be supported for some time, most likely until v8 in 2026, but will be eventually removed in favor of REST API.
+// Deprecated: The gRPC API will remain the default and fully supported through v8 (expected in 2026) but will be eventually removed in favor of REST API.
 //
 // GetSyncCommitteeContribution is called by a sync committee aggregator
 // to retrieve sync committee contribution object.
@@ -106,7 +106,7 @@ func (vs *Server) GetSyncCommitteeContribution(
 	return contribution, nil
 }
 
-// Deprecated: gRPC API will still be supported for some time, most likely until v8 in 2026, but will be eventually removed in favor of REST API.
+// Deprecated: The gRPC API will remain the default and fully supported through v8 (expected in 2026) but will be eventually removed in favor of REST API.
 //
 // SubmitSignedContributionAndProof is called by a sync committee aggregator
 // to submit signed contribution and proof object.
@@ -120,7 +120,7 @@ func (vs *Server) SubmitSignedContributionAndProof(
 	return &emptypb.Empty{}, nil
 }
 
-// Deprecated: gRPC API will still be supported for some time, most likely until v8 in 2026, but will be eventually removed in favor of REST API.
+// Deprecated: The gRPC API will remain the default and fully supported through v8 (expected in 2026) but will be eventually removed in favor of REST API.
 //
 // AggregatedSigAndAggregationBits returns the aggregated signature and aggregation bits
 // associated with a particular set of sync committee messages.

beacon-chain/state/state-native/getters_withdrawal.go

@@ -62,9 +62,11 @@ func (b *BeaconState) NextWithdrawalValidatorIndex() (primitives.ValidatorIndex,
 //
 //			validator = state.validators[withdrawal.index]
 //			has_sufficient_effective_balance = validator.effective_balance >= MIN_ACTIVATION_BALANCE
-//			has_excess_balance = state.balances[withdrawal.index] > MIN_ACTIVATION_BALANCE
+//			total_withdrawn = sum(w.amount for w in withdrawals if w.validator_index == withdrawal.validator_index)
+//			balance = state.balances[withdrawal.validator_index] - total_withdrawn
+//			has_excess_balance = balance > MIN_ACTIVATION_BALANCE
 //			if validator.exit_epoch == FAR_FUTURE_EPOCH and has_sufficient_effective_balance and has_excess_balance:
-//				withdrawable_balance = min(state.balances[withdrawal.index] - MIN_ACTIVATION_BALANCE, withdrawal.amount)
+//				withdrawable_balance = min(balance - MIN_ACTIVATION_BALANCE, withdrawal.amount)
 //				withdrawals.append(Withdrawal(
 //					index=withdrawal_index,
 //					validator_index=withdrawal.index,
@@ -132,9 +134,19 @@ func (b *BeaconState) ExpectedWithdrawals() ([]*enginev1.Withdrawal, uint64, err
 				return nil, 0, fmt.Errorf("could not retrieve balance at index %d: %w", w.Index, err)
 			}
 			hasSufficientEffectiveBalance := v.EffectiveBalance() >= params.BeaconConfig().MinActivationBalance
-			hasExcessBalance := vBal > params.BeaconConfig().MinActivationBalance
+			var totalWithdrawn uint64
+			for _, wi := range withdrawals {
+				if wi.ValidatorIndex == w.Index {
+					totalWithdrawn += wi.Amount
+				}
+			}
+			balance, err := mathutil.Sub64(vBal, totalWithdrawn)
+			if err != nil {
+				return nil, 0, errors.Wrapf(err, "failed to subtract balance %d with total withdrawn %d", vBal, totalWithdrawn)
+			}
+			hasExcessBalance := balance > params.BeaconConfig().MinActivationBalance
 			if v.ExitEpoch() == params.BeaconConfig().FarFutureEpoch && hasSufficientEffectiveBalance && hasExcessBalance {
-				amount := min(vBal-params.BeaconConfig().MinActivationBalance, w.Amount)
+				amount := min(balance-params.BeaconConfig().MinActivationBalance, w.Amount)
 				withdrawals = append(withdrawals, &enginev1.Withdrawal{
 					Index:          withdrawalIndex,
 					ValidatorIndex: w.Index,
@@ -165,7 +177,10 @@ func (b *BeaconState) ExpectedWithdrawals() ([]*enginev1.Withdrawal, uint64, err
 					partiallyWithdrawnBalance += w.Amount
 				}
 			}
-			balance = balance - partiallyWithdrawnBalance
+			balance, err = mathutil.Sub64(balance, partiallyWithdrawnBalance)
+			if err != nil {
+				return nil, 0, errors.Wrapf(err, "could not subtract balance %d with partial withdrawn balance %d", balance, partiallyWithdrawnBalance)
+			}
 		}
 		if helpers.IsFullyWithdrawableValidator(val, balance, epoch, b.version) {
 			withdrawals = append(withdrawals, &enginev1.Withdrawal{

beacon-chain/state/state-native/getters_withdrawal_test.go

@@ -416,3 +416,37 @@ func TestExpectedWithdrawals(t *testing.T) {
 		require.DeepEqual(t, withdrawalFull, expected[1])
 	})
 }
+
+func TestExpectedWithdrawals_underflow_electra(t *testing.T) {
+	s, err := state_native.InitializeFromProtoUnsafeElectra(&ethpb.BeaconStateElectra{})
+	require.NoError(t, err)
+	vals := make([]*ethpb.Validator, 1)
+	balances := make([]uint64, 1)
+	balances[0] = 2015_000_000_000 //Validator A begins leaking ETH due to inactivity, and over time, its balance decreases to 2,015 ETH
+	val := &ethpb.Validator{
+		WithdrawalCredentials: make([]byte, 32),
+		EffectiveBalance:      params.BeaconConfig().MaxEffectiveBalanceElectra,
+		WithdrawableEpoch:     primitives.Epoch(0),
+		ExitEpoch:             params.BeaconConfig().FarFutureEpoch,
+	}
+	val.WithdrawalCredentials[0] = params.BeaconConfig().CompoundingWithdrawalPrefixByte
+	val.WithdrawalCredentials[31] = byte(0)
+	vals[0] = val
+
+	require.NoError(t, s.SetValidators(vals))
+	require.NoError(t, s.SetBalances(balances))
+	require.NoError(t, s.AppendPendingPartialWithdrawal(&ethpb.PendingPartialWithdrawal{
+		Amount:            1008_000_000_000,
+		WithdrawableEpoch: primitives.Epoch(0),
+	}))
+	require.NoError(t, s.AppendPendingPartialWithdrawal(&ethpb.PendingPartialWithdrawal{
+		Amount:            1008_000_000_000,
+		WithdrawableEpoch: primitives.Epoch(0),
+	}))
+	expected, _, err := s.ExpectedWithdrawals()
+	require.NoError(t, err)
+	require.Equal(t, 3, len(expected)) // is a fully withdrawable validator
+	require.Equal(t, uint64(1008_000_000_000), expected[0].Amount)
+	require.Equal(t, uint64(975_000_000_000), expected[1].Amount)
+	require.Equal(t, uint64(32_000_000_000), expected[2].Amount)
+}

beacon-chain/state/stategen/getter.go

@@ -259,7 +259,7 @@ func (s *State) latestAncestor(ctx context.Context, blockRoot [32]byte) (state.B
 	defer span.End()
 
 	if s.isFinalizedRoot(blockRoot) {
-		finalizedState := s.finalizedState()
+		finalizedState := s.FinalizedState()
 		if finalizedState != nil {
 			return finalizedState, nil
 		}
@@ -297,7 +297,7 @@ func (s *State) latestAncestor(ctx context.Context, blockRoot [32]byte) (state.B
 
 		// Does the state exist in finalized info cache.
 		if s.isFinalizedRoot(parentRoot) {
-			return s.finalizedState(), nil
+			return s.FinalizedState(), nil
 		}
 
 		// Does the state exist in epoch boundary cache.

beacon-chain/state/stategen/mock/mock.go

@@ -23,8 +23,8 @@ func NewService() *StateManager {
 }
 
 // StateByRootIfCachedNoCopy --
-func (_ *StateManager) StateByRootIfCachedNoCopy(_ [32]byte) state.BeaconState {
-	panic("implement me")
+func (m *StateManager) StateByRootIfCachedNoCopy(root [32]byte) state.BeaconState {
+	return m.StatesByRoot[root]
 }
 
 // Resume --

beacon-chain/state/stategen/service.go

@@ -196,7 +196,7 @@ func (s *State) isFinalizedRoot(r [32]byte) bool {
 }
 
 // Returns the cached and copied finalized state.
-func (s *State) finalizedState() state.BeaconState {
+func (s *State) FinalizedState() state.BeaconState {
 	s.finalizedInfo.lock.RLock()
 	defer s.finalizedInfo.lock.RUnlock()
 	return s.finalizedInfo.state.Copy()

beacon-chain/state/stategen/service_test.go

@@ -33,5 +33,5 @@ func TestResume(t *testing.T) {
 	require.DeepSSZEqual(t, beaconState.ToProtoUnsafe(), resumeState.ToProtoUnsafe())
 	assert.Equal(t, params.BeaconConfig().SlotsPerEpoch, service.finalizedInfo.slot, "Did not get watned slot")
 	assert.Equal(t, service.finalizedInfo.root, root, "Did not get wanted root")
-	assert.NotNil(t, service.finalizedState(), "Wanted a non nil finalized state")
+	assert.NotNil(t, service.FinalizedState(), "Wanted a non nil finalized state")
 }

beacon-chain/sync/BUILD.bazel

@@ -229,6 +229,7 @@ go_test(
         "//beacon-chain/operations/attestations:go_default_library",
         "//beacon-chain/operations/blstoexec:go_default_library",
         "//beacon-chain/operations/slashings:go_default_library",
+        "//beacon-chain/operations/slashings/mock:go_default_library",
         "//beacon-chain/p2p:go_default_library",
         "//beacon-chain/p2p/encoder:go_default_library",
         "//beacon-chain/p2p/peers:go_default_library",

beacon-chain/sync/data_columns.go

@@ -204,7 +204,6 @@ func RequestMissingDataColumnsByRange(
 	rateLimiter *leakybucket.Collector,
 	groupCount uint64,
 	dataColumnsStorage filesystem.DataColumnStorageSummarizer,
-	peers []peer.ID,
 	blks []blocks.ROBlock,
 	batchSize int,
 ) (map[[fieldparams.RootLength]byte][]blocks.RODataColumn, error) {
@@ -285,7 +284,7 @@ func RequestMissingDataColumnsByRange(
 		// Requests data column sidecars from peers.
 		retrievedDataColumnsByRoot := make(map[[fieldparams.RootLength]byte][]blocks.RODataColumn)
 		for _, request := range requests {
-			roDataColumns, err := fetchDataColumnsFromPeers(ctx, clock, p2p, rateLimiter, ctxMap, peers, request)
+			roDataColumns, err := fetchDataColumnsFromPeers(ctx, clock, p2p, rateLimiter, ctxMap, request)
 			if err != nil {
 				return nil, errors.Wrap(err, "fetch data columns from peers")
 			}
@@ -576,17 +575,9 @@ func custodyColumnsFromPeers(peers []peer.ID, p2p p2p.P2P) (map[peer.ID]map[uint
 // `filterPeerWhichCustodyAtLeastOneDataColumn` filters peers which custody at least one data column
 // specified in `neededDataColumns`. It returns also a list of descriptions for non admissible peers.
 func filterPeerWhichCustodyAtLeastOneDataColumn(neededDataColumns []uint64, inputDataColumnsByPeer map[peer.ID]map[uint64]bool) (map[peer.ID]map[uint64]bool, []string) {
-	// Get the count of needed data columns.
-	neededDataColumnsCount := uint64(len(neededDataColumns))
-
 	// Create pretty needed data columns for logs.
-	var neededDataColumnsLog interface{} = "all"
 	numberOfColumns := params.BeaconConfig().NumberOfColumns
 
-	if neededDataColumnsCount < numberOfColumns {
-		neededDataColumnsLog = neededDataColumns
-	}
-
 	outputDataColumnsByPeer := make(map[peer.ID]map[uint64]bool, len(inputDataColumnsByPeer))
 	descriptions := make([]string, 0)
 
@@ -607,11 +598,7 @@ outerLoop:
 			peerCustodyColumnsLog = uint64MapToSortedSlice(peerCustodyDataColumns)
 		}
 
-		description := fmt.Sprintf(
-			"peer %s: does not custody any needed column, custody columns: %v, needed columns: %v",
-			peer, peerCustodyColumnsLog, neededDataColumnsLog,
-		)
-
+		description := fmt.Sprintf("peer %s: does not custody any needed column, custody columns: %v", peer, peerCustodyColumnsLog)
 		descriptions = append(descriptions, description)
 	}
 
@@ -720,7 +707,6 @@ func fetchDataColumnsFromPeers(
 	p2p p2p.P2P,
 	rateLimiter *leakybucket.Collector,
 	ctxMap ContextByteVersions,
-	peers []peer.ID,
 	targetRequest *eth.DataColumnSidecarsByRangeRequest,
 ) ([]blocks.RODataColumn, error) {
 	// Filter out requests with no data columns.
@@ -729,7 +715,7 @@ func fetchDataColumnsFromPeers(
 	}
 
 	// Get all admissible peers with the data columns they custody.
-	dataColumnsByAdmissiblePeer, err := waitForPeersForDataColumns(p2p, rateLimiter, peers, targetRequest)
+	dataColumnsByAdmissiblePeer, err := waitForPeersForDataColumns(p2p, rateLimiter, targetRequest)
 	if err != nil {
 		return nil, errors.Wrap(err, "wait for peers for data columns")
 	}
@@ -766,7 +752,7 @@ func fetchDataColumnsFromPeers(
 // - synced up to `lastSlot`, and
 // - have bandwidth to serve `blockCount` blocks.
 // It waits until at least one peer per data column is available.
-func waitForPeersForDataColumns(p2p p2p.P2P, rateLimiter *leakybucket.Collector, peers []peer.ID, request *eth.DataColumnSidecarsByRangeRequest) (map[peer.ID]map[uint64]bool, error) {
+func waitForPeersForDataColumns(p2p p2p.P2P, rateLimiter *leakybucket.Collector, request *eth.DataColumnSidecarsByRangeRequest) (map[peer.ID]map[uint64]bool, error) {
 	const delay = 5 * time.Second
 
 	numberOfColumns := params.BeaconConfig().NumberOfColumns
@@ -788,7 +774,7 @@ func waitForPeersForDataColumns(p2p p2p.P2P, rateLimiter *leakybucket.Collector,
 
 	// Keep only peers with head epoch greater than or equal to the epoch corresponding to the target slot, and
 	// keep only peers with enough bandwidth.
-	filteredPeers, descriptions, err := filterPeersByTargetSlotAndBandwidth(p2p, rateLimiter, peers, lastSlot, request.Count)
+	filteredPeers, descriptions, err := filterPeersByTargetSlotAndBandwidth(p2p, rateLimiter, lastSlot, request.Count)
 	if err != nil {
 		return nil, errors.Wrap(err, "filter eers by target slot and bandwidth")
 	}
@@ -834,7 +820,7 @@ func waitForPeersForDataColumns(p2p p2p.P2P, rateLimiter *leakybucket.Collector,
 		time.Sleep(delay)
 
 		// Filter for peers with head epoch greater than or equal to our target epoch for ByRange requests.
-		filteredPeers, descriptions, err = filterPeersByTargetSlotAndBandwidth(p2p, rateLimiter, peers, lastSlot, request.Count)
+		filteredPeers, descriptions, err = filterPeersByTargetSlotAndBandwidth(p2p, rateLimiter, lastSlot, request.Count)
 		if err != nil {
 			return nil, errors.Wrap(err, "filter peers by target slot and bandwidth")
 		}
@@ -855,10 +841,8 @@ func waitForPeersForDataColumns(p2p p2p.P2P, rateLimiter *leakybucket.Collector,
 }
 
 // Filter peers to ensure they are synced to the target slot and have sufficient bandwidth to serve the request.
-func filterPeersByTargetSlotAndBandwidth(p2p p2p.P2P, rateLimiter *leakybucket.Collector, peers []peer.ID, lastSlot primitives.Slot, blockCount uint64) ([]peer.ID, []string, error) {
-	if len(peers) == 0 {
-		peers = p2p.Peers().Connected()
-	}
+func filterPeersByTargetSlotAndBandwidth(p2p p2p.P2P, rateLimiter *leakybucket.Collector, lastSlot primitives.Slot, blockCount uint64) ([]peer.ID, []string, error) {
+	peers := p2p.Peers().Connected()
 
 	slotPeers, descriptions, err := filterPeersByTargetSlot(p2p, peers, lastSlot)
 	if err != nil {

beacon-chain/sync/data_columns_test.go

@@ -585,7 +585,11 @@ func TestRequestDataColumnSidecarsByRoot(t *testing.T) {
 
 			ctxMap := map[[4]byte]int{{245, 165, 253, 66}: version.Fulu}
 			verifier := func(cols []blocks.RODataColumn, reqs []verification.Requirement) verification.DataColumnsVerifier {
-				initializer := &verification.Initializer{}
+				clockSync := startup.NewClockSynchronizer()
+				require.NoError(t, clockSync.SetClock(clock))
+				w := verification.NewInitializerWaiter(clockSync, nil, nil)
+				initializer, err := w.WaitForInitializer(context.Background())
+				require.NoError(t, err)
 				return initializer.NewDataColumnsVerifier(cols, reqs)
 			}
 
@@ -1472,7 +1476,7 @@ func TestFetchDataColumnsFromPeers(t *testing.T) {
 			rateLimiter := leakybucket.NewCollector(1_000, 1_000, 1*time.Hour, false)
 
 			// Fetch the data columns from the peers.
-			fetchedRoDataColumnsByRoot, err := RequestMissingDataColumnsByRange(ctx, clock, ctxMap, p2pSvc, rateLimiter, 4, dataColumnStorageSummarizer, peersID, roBlocks, tc.batchSize)
+			fetchedRoDataColumnsByRoot, err := RequestMissingDataColumnsByRange(ctx, clock, ctxMap, p2pSvc, rateLimiter, 4, dataColumnStorageSummarizer, roBlocks, tc.batchSize)
 			if !tc.isError {
 				require.NoError(t, err)
 			} else {

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

@@ -61,6 +61,7 @@ go_test(
         "blocks_fetcher_test.go",
         "blocks_fetcher_utils_test.go",
         "blocks_queue_test.go",
+        "downscore_test.go",
         "fsm_benchmark_test.go",
         "fsm_test.go",
         "initial_sync_test.go",
@@ -71,6 +72,7 @@ go_test(
     tags = ["CI_race_detection"],
     deps = [
         "//async/abool:go_default_library",
+        "//beacon-chain/blockchain:go_default_library",
         "//beacon-chain/blockchain/testing:go_default_library",
         "//beacon-chain/core/peerdas:go_default_library",
         "//beacon-chain/das:go_default_library",
@@ -80,6 +82,7 @@ go_test(
         "//beacon-chain/db/testing:go_default_library",
         "//beacon-chain/p2p:go_default_library",
         "//beacon-chain/p2p/peers:go_default_library",
+        "//beacon-chain/p2p/peers/peerdata:go_default_library",
         "//beacon-chain/p2p/peers/scorers:go_default_library",
         "//beacon-chain/p2p/testing:go_default_library",
         "//beacon-chain/p2p/types:go_default_library",
@@ -107,6 +110,7 @@ go_test(
         "@com_github_libp2p_go_libp2p//core/network:go_default_library",
         "@com_github_libp2p_go_libp2p//core/peer:go_default_library",
         "@com_github_paulbellamy_ratecounter//:go_default_library",
+        "@com_github_pkg_errors//:go_default_library",
         "@com_github_sirupsen_logrus//:go_default_library",
         "@com_github_sirupsen_logrus//hooks/test:go_default_library",
     ],

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

@@ -129,11 +129,20 @@ type fetchRequestParams struct {
 // fetchRequestResponse is a combined type to hold results of both successful executions and errors.
 // Valid usage pattern will be to check whether result's `err` is nil, before using `blocks`.
 type fetchRequestResponse struct {
-	pid   peer.ID
-	start primitives.Slot
-	count uint64
-	bwb   []blocks.BlockWithROSidecars
-	err   error
+	blocksFrom peer.ID
+	blobsFrom  peer.ID
+	start      primitives.Slot
+	count      uint64
+	bwb        []blocks.BlockWithROSidecars
+	err        error
+}
+
+func (r *fetchRequestResponse) blocksQueueFetchedData() *blocksQueueFetchedData {
+	return &blocksQueueFetchedData{
+		blocksFrom: r.blocksFrom,
+		blobsFrom:  r.blobsFrom,
+		bwb:        r.bwb,
+	}
 }
 
 // newBlocksFetcher creates ready to use fetcher.
@@ -330,20 +339,22 @@ func (f *blocksFetcher) handleRequest(ctx context.Context, start primitives.Slot
 		}
 	}
 
-	response.bwb, response.pid, response.err = f.fetchBlocksFromPeer(ctx, start, count, peers)
-	if response.err != nil {
-		return response
-	}
+	response.bwb, response.blocksFrom, response.err = f.fetchBlocksFromPeer(ctx, start, count, peers)
+	if response.err == nil {
+		pid, err := f.fetchSidecars(ctx, response.blocksFrom, peers, response.bwb)
+		if err != nil {
+			response.err = err
+		}
 
-	// Fetch sidecars for blocks in `response.bwb`.
-	response.err = f.fetchSidecars(ctx, response.pid, peers, response.bwb)
+		response.blobsFrom = pid
+	}
 
 	return response
 }
 
 // fetchSidecars fetches sidecars corresponding to blocks in `response.bwb`.
 // It mutates `Blobs` and `Columns` fields of `response.bwb` with fetched sidecars.
-func (f *blocksFetcher) fetchSidecars(ctx context.Context, pid peer.ID, peers []peer.ID, bwScs []blocks.BlockWithROSidecars) error {
+func (f *blocksFetcher) fetchSidecars(ctx context.Context, pid peer.ID, peers []peer.ID, bwScs []blocks.BlockWithROSidecars) (peer.ID, error) {
 	const batchSize = 32
 
 	// Find the first block with a slot greater than or equal to the first Fulu slot.
@@ -355,15 +366,25 @@ func (f *blocksFetcher) fetchSidecars(ctx context.Context, pid peer.ID, peers []
 	blocksWithBlobs := bwScs[:firstFuluIndex]
 	blocksWithDataColumns := bwScs[firstFuluIndex:]
 
+	if len(blocksWithBlobs) == 0 && len(blocksWithDataColumns) == 0 {
+		return "", nil
+	}
+
+	var (
+		blobsPid peer.ID
+		err      error
+	)
+
 	if len(blocksWithBlobs) > 0 {
 		// Fetch blob sidecars.
-		if err := f.fetchBlobsFromPeer(ctx, blocksWithBlobs, pid, peers); err != nil {
-			return errors.Wrap(err, "fetch blobs from peer")
+		blobsPid, err = f.fetchBlobsFromPeer(ctx, blocksWithBlobs, pid, peers)
+		if err != nil {
+			return "", errors.Wrap(err, "fetch blobs from peer")
 		}
 	}
 
 	if len(blocksWithDataColumns) == 0 {
-		return nil
+		return blobsPid, nil
 	}
 
 	// Extract blocks.
@@ -375,9 +396,9 @@ func (f *blocksFetcher) fetchSidecars(ctx context.Context, pid peer.ID, peers []
 
 	// Fetch data column sidecars.
 	actualGroupCount := f.custodyInfo.ActualGroupCount()
-	fetchedDataColumnsByRoot, err := prysmsync.RequestMissingDataColumnsByRange(ctx, f.clock, f.ctxMap, f.p2p, f.rateLimiter, actualGroupCount, f.dcs, peers, dataColumnBlocks, batchSize)
+	fetchedDataColumnsByRoot, err := prysmsync.RequestMissingDataColumnsByRange(ctx, f.clock, f.ctxMap, f.p2p, f.rateLimiter, actualGroupCount, f.dcs, dataColumnBlocks, batchSize)
 	if err != nil {
-		return errors.Wrap(err, "fetch missing data columns from peers")
+		return blobsPid, errors.Wrap(err, "fetch missing data columns from peers")
 	}
 
 	// Populate the response.
@@ -389,7 +410,8 @@ func (f *blocksFetcher) fetchSidecars(ctx context.Context, pid peer.ID, peers []
 		}
 	}
 
-	return nil
+	// TODO: Return the (multiple) peer IDs that provided the data columns and not only the one for blobs.
+	return blobsPid, nil
 }
 
 // fetchBlocksFromPeer fetches blocks from a single randomly selected peer, sorted by slot.
@@ -613,24 +635,24 @@ func missingCommitError(root [32]byte, slot primitives.Slot, missing [][]byte) e
 
 // fetchBlobsFromPeer fetches blocks from a single randomly selected peer.
 // This function mutates the input `bwb` argument.
-func (f *blocksFetcher) fetchBlobsFromPeer(ctx context.Context, bwb []blocks.BlockWithROSidecars, pid peer.ID, peers []peer.ID) error {
+func (f *blocksFetcher) fetchBlobsFromPeer(ctx context.Context, bwb []blocks.BlockWithROSidecars, pid peer.ID, peers []peer.ID) (peer.ID, error) {
 	if len(bwb) == 0 {
-		return nil
+		return "", nil
 	}
 
 	ctx, span := trace.StartSpan(ctx, "initialsync.fetchBlobsFromPeer")
 	defer span.End()
 	if slots.ToEpoch(f.clock.CurrentSlot()) < params.BeaconConfig().DenebForkEpoch {
-		return nil
+		return "", nil
 	}
 	blobWindowStart, err := prysmsync.BlobRPCMinValidSlot(f.clock.CurrentSlot())
 	if err != nil {
-		return err
+		return "", err
 	}
 	// Construct request message based on observed interval of blocks in need of blobs.
 	req := countCommitments(bwb, blobWindowStart).blobRange(f.bs).Request()
 	if req == nil {
-		return nil
+		return "", nil
 	}
 	peers = f.filterPeers(ctx, peers, peersPercentagePerRequest)
 	// We dial the initial peer first to ensure that we get the desired set of blobs.
@@ -652,9 +674,9 @@ func (f *blocksFetcher) fetchBlobsFromPeer(ctx context.Context, bwb []blocks.Blo
 			log.WithField("peer", p).WithError(err).Debug("Invalid BeaconBlobsByRange response")
 			continue
 		}
-		return err
+		return p, err
 	}
-	return errNoPeersAvailable
+	return "", errNoPeersAvailable
 }
 
 // sortedSliceFromMap returns a sorted slice of keys from a map.

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

@@ -22,8 +22,9 @@ import (
 // Blocks are stored in an ascending slot order. The first block is guaranteed to have parent
 // either in DB or initial sync cache.
 type forkData struct {
-	peer peer.ID
-	bwb  []blocks.BlockWithROSidecars
+	blocksFrom peer.ID
+	blobsFrom  peer.ID
+	bwb        []blocks.BlockWithROSidecars
 }
 
 // nonSkippedSlotAfter checks slots after the given one in an attempt to find a non-empty future slot.
@@ -279,16 +280,16 @@ func (f *blocksFetcher) findForkWithPeer(ctx context.Context, pid peer.ID, peers
 			return nil, errors.Wrap(err, "invalid blocks received in findForkWithPeer")
 		}
 
-		if err := f.fetchSidecars(ctx, pid, peers, bwb); err != nil {
+		sidecarsPid, err := f.fetchSidecars(ctx, pid, peers, bwb)
+		if err != nil {
 			return nil, errors.Wrap(err, "fetch sidecars")
 		}
 
 		// We need to fetch the blobs for the given alt-chain if any exist, so that we can try to verify and import
 		// the blocks.
-
 		// The caller will use the BlocksWith VerifiedBlobs in bwb as the starting point for
 		// round-robin syncing the alternate chain.
-		return &forkData{peer: pid, bwb: bwb}, nil
+		return &forkData{blocksFrom: pid, blobsFrom: sidecarsPid, bwb: bwb}, nil
 	}
 	return nil, errNoAlternateBlocks
 }
@@ -304,12 +305,14 @@ func (f *blocksFetcher) findAncestor(ctx context.Context, pid peer.ID, peers []p
 			if err != nil {
 				return nil, errors.Wrap(err, "received invalid blocks in findAncestor")
 			}
-			if err := f.fetchSidecars(ctx, pid, peers, bwb); err != nil {
+			sidecarsPid, err := f.fetchSidecars(ctx, pid, peers, bwb)
+			if err != nil {
 				return nil, errors.Wrap(err, "fetch sidecars")
 			}
 			return &forkData{
-				peer: pid,
-				bwb:  bwb,
+				blocksFrom: pid,
+				bwb:        bwb,
+				blobsFrom:  sidecarsPid,
 			}, nil
 		}
 		// Request block's parent.

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

@@ -265,7 +265,7 @@ func TestBlocksFetcher_findFork(t *testing.T) {
 	reqEnd := testForkStartSlot(t, 251) + primitives.Slot(findForkReqRangeSize())
 	require.Equal(t, primitives.Slot(len(chain1)), fork.bwb[0].Block.Block().Slot())
 	require.Equal(t, int(reqEnd-forkSlot1b), len(fork.bwb))
-	require.Equal(t, curForkMoreBlocksPeer, fork.peer)
+	require.Equal(t, curForkMoreBlocksPeer, fork.blocksFrom)
 	// Save all chain1b blocks (so that they do not interfere with alternative fork)
 	for _, blk := range chain1b {
 		util.SaveBlock(t, ctx, beaconDB, blk)
@@ -285,7 +285,7 @@ func TestBlocksFetcher_findFork(t *testing.T) {
 	alternativePeer := connectPeerHavingBlocks(t, p2p, chain2, finalizedSlot, p2p.Peers())
 	fork, err = fetcher.findFork(ctx, 251)
 	require.NoError(t, err)
-	assert.Equal(t, alternativePeer, fork.peer)
+	assert.Equal(t, alternativePeer, fork.blocksFrom)
 	assert.Equal(t, 65, len(fork.bwb))
 	ind := forkSlot
 	for _, blk := range fork.bwb {

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

@@ -99,8 +99,9 @@ type blocksQueue struct {
 
 // blocksQueueFetchedData is a data container that is returned from a queue on each step.
 type blocksQueueFetchedData struct {
-	pid peer.ID
-	bwb []blocks.BlockWithROSidecars
+	blocksFrom peer.ID
+	blobsFrom  peer.ID
+	bwb        []blocks.BlockWithROSidecars
 }
 
 // newBlocksQueue creates initialized priority queue.
@@ -347,13 +348,15 @@ func (q *blocksQueue) onDataReceivedEvent(ctx context.Context) eventHandlerFn {
 			}
 			if errors.Is(response.err, beaconsync.ErrInvalidFetchedData) {
 				// Peer returned invalid data, penalize.
-				q.blocksFetcher.p2p.Peers().Scorers().BadResponsesScorer().Increment(m.pid)
-				log.WithField("pid", response.pid).Debug("Peer is penalized for invalid blocks")
+				q.blocksFetcher.p2p.Peers().Scorers().BadResponsesScorer().Increment(response.blocksFrom)
+				log.WithField("pid", response.blocksFrom).Debug("Peer is penalized for invalid blocks")
+			} else if errors.Is(response.err, verification.ErrBlobInvalid) {
+				q.blocksFetcher.p2p.Peers().Scorers().BadResponsesScorer().Increment(response.blobsFrom)
+				log.WithField("pid", response.blobsFrom).Debug("Peer is penalized for invalid blob response")
 			}
 			return m.state, response.err
 		}
-		m.pid = response.pid
-		m.bwb = response.bwb
+		m.fetched = *response
 		return stateDataParsed, nil
 	}
 }
@@ -368,19 +371,15 @@ func (q *blocksQueue) onReadyToSendEvent(ctx context.Context) eventHandlerFn {
 			return m.state, errInvalidInitialState
 		}
 
-		if len(m.bwb) == 0 {
+		if m.numFetched() == 0 {
 			return stateSkipped, nil
 		}
 
 		send := func() (stateID, error) {
-			data := &blocksQueueFetchedData{
-				pid: m.pid,
-				bwb: m.bwb,
-			}
 			select {
 			case <-ctx.Done():
 				return m.state, ctx.Err()
-			case q.fetchedData <- data:
+			case q.fetchedData <- m.fetched.blocksQueueFetchedData():
 			}
 			return stateSent, nil
 		}

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

@@ -477,8 +477,8 @@ func TestBlocksQueue_onDataReceivedEvent(t *testing.T) {
 		updatedState, err := handlerFn(&stateMachine{
 			state: stateScheduled,
 		}, &fetchRequestResponse{
-			pid: "abc",
-			err: errSlotIsTooHigh,
+			blocksFrom: "abc",
+			err:        errSlotIsTooHigh,
 		})
 		assert.ErrorContains(t, errSlotIsTooHigh.Error(), err)
 		assert.Equal(t, stateScheduled, updatedState)
@@ -500,9 +500,9 @@ func TestBlocksQueue_onDataReceivedEvent(t *testing.T) {
 		updatedState, err := handlerFn(&stateMachine{
 			state: stateScheduled,
 		}, &fetchRequestResponse{
-			pid:   "abc",
-			err:   errSlotIsTooHigh,
-			start: 256,
+			blocksFrom: "abc",
+			err:        errSlotIsTooHigh,
+			start:      256,
 		})
 		assert.ErrorContains(t, errSlotIsTooHigh.Error(), err)
 		assert.Equal(t, stateScheduled, updatedState)
@@ -522,8 +522,8 @@ func TestBlocksQueue_onDataReceivedEvent(t *testing.T) {
 		updatedState, err := handlerFn(&stateMachine{
 			state: stateScheduled,
 		}, &fetchRequestResponse{
-			pid: "abc",
-			err: beaconsync.ErrInvalidFetchedData,
+			blocksFrom: "abc",
+			err:        beaconsync.ErrInvalidFetchedData,
 		})
 		assert.ErrorContains(t, beaconsync.ErrInvalidFetchedData.Error(), err)
 		assert.Equal(t, stateScheduled, updatedState)
@@ -542,7 +542,7 @@ func TestBlocksQueue_onDataReceivedEvent(t *testing.T) {
 		wsbCopy, err := wsb.Copy()
 		require.NoError(t, err)
 		response := &fetchRequestResponse{
-			pid: "abc",
+			blocksFrom: "abc",
 			bwb: []blocks.BlockWithROSidecars{
 				{Block: blocks.ROBlock{ReadOnlySignedBeaconBlock: wsb}},
 				{Block: blocks.ROBlock{ReadOnlySignedBeaconBlock: wsbCopy}},
@@ -551,13 +551,15 @@ func TestBlocksQueue_onDataReceivedEvent(t *testing.T) {
 		fsm := &stateMachine{
 			state: stateScheduled,
 		}
-		assert.Equal(t, peer.ID(""), fsm.pid)
-		assert.Equal(t, 0, len(fsm.bwb))
+		assert.Equal(t, peer.ID(""), fsm.fetched.blocksFrom)
+		assert.Equal(t, peer.ID(""), fsm.fetched.blobsFrom)
+		assert.Equal(t, 0, fsm.numFetched())
 		updatedState, err := handlerFn(fsm, response)
 		assert.NoError(t, err)
 		assert.Equal(t, stateDataParsed, updatedState)
-		assert.Equal(t, response.pid, fsm.pid)
-		assert.DeepSSZEqual(t, response.bwb, fsm.bwb)
+		assert.Equal(t, response.blocksFrom, fsm.fetched.blocksFrom)
+		assert.Equal(t, response.blobsFrom, fsm.fetched.blobsFrom)
+		assert.DeepSSZEqual(t, response.bwb, fsm.fetched.bwb)
 	})
 }
 
@@ -642,10 +644,10 @@ func TestBlocksQueue_onReadyToSendEvent(t *testing.T) {
 		queue.smm.addStateMachine(256)
 		queue.smm.addStateMachine(320)
 		queue.smm.machines[256].state = stateDataParsed
-		queue.smm.machines[256].pid = pidDataParsed
+		queue.smm.machines[256].fetched.blocksFrom = pidDataParsed
 		rwsb, err := blocks.NewROBlock(wsb)
 		require.NoError(t, err)
-		queue.smm.machines[256].bwb = []blocks.BlockWithROSidecars{
+		queue.smm.machines[256].fetched.bwb = []blocks.BlockWithROSidecars{
 			{Block: rwsb},
 		}
 
@@ -677,10 +679,10 @@ func TestBlocksQueue_onReadyToSendEvent(t *testing.T) {
 		queue.smm.machines[256].state = stateDataParsed
 		queue.smm.addStateMachine(320)
 		queue.smm.machines[320].state = stateDataParsed
-		queue.smm.machines[320].pid = pidDataParsed
+		queue.smm.machines[320].fetched.blocksFrom = pidDataParsed
 		rwsb, err := blocks.NewROBlock(wsb)
 		require.NoError(t, err)
-		queue.smm.machines[320].bwb = []blocks.BlockWithROSidecars{
+		queue.smm.machines[320].fetched.bwb = []blocks.BlockWithROSidecars{
 			{Block: rwsb},
 		}
 
@@ -709,10 +711,10 @@ func TestBlocksQueue_onReadyToSendEvent(t *testing.T) {
 		queue.smm.machines[256].state = stateSkipped
 		queue.smm.addStateMachine(320)
 		queue.smm.machines[320].state = stateDataParsed
-		queue.smm.machines[320].pid = pidDataParsed
+		queue.smm.machines[320].fetched.blocksFrom = pidDataParsed
 		rwsb, err := blocks.NewROBlock(wsb)
 		require.NoError(t, err)
-		queue.smm.machines[320].bwb = []blocks.BlockWithROSidecars{
+		queue.smm.machines[320].fetched.bwb = []blocks.BlockWithROSidecars{
 			{Block: rwsb},
 		}
 
@@ -1213,17 +1215,17 @@ func TestBlocksQueue_stuckInUnfavourableFork(t *testing.T) {
 		firstFSM, ok := queue.smm.findStateMachine(forkedSlot)
 		require.Equal(t, true, ok)
 		require.Equal(t, stateDataParsed, firstFSM.state)
-		require.Equal(t, forkedPeer, firstFSM.pid)
+		require.Equal(t, forkedPeer, firstFSM.fetched.blocksFrom)
 		reqEnd := testForkStartSlot(t, 251) + primitives.Slot(findForkReqRangeSize())
-		require.Equal(t, int(reqEnd-forkedSlot), len(firstFSM.bwb))
-		require.Equal(t, forkedSlot, firstFSM.bwb[0].Block.Block().Slot())
+		require.Equal(t, int(reqEnd-forkedSlot), len(firstFSM.fetched.bwb))
+		require.Equal(t, forkedSlot, firstFSM.fetched.bwb[0].Block.Block().Slot())
 
 		// Assert that forked data from chain2 is available (within 64 fetched blocks).
 		for i, blk := range chain2[forkedSlot:] {
-			if i >= len(firstFSM.bwb) {
+			if i >= len(firstFSM.fetched.bwb) {
 				break
 			}
-			rootFromFSM := firstFSM.bwb[i].Block.Root()
+			rootFromFSM := firstFSM.fetched.bwb[i].Block.Root()
 			blkRoot, err := blk.Block.HashTreeRoot()
 			require.NoError(t, err)
 			assert.Equal(t, blkRoot, rootFromFSM)
@@ -1231,7 +1233,7 @@ func TestBlocksQueue_stuckInUnfavourableFork(t *testing.T) {
 
 		// Assert that machines are in the expected state.
 		startSlot = forkedEpochStartSlot.Add(1 + blocksPerRequest)
-		require.Equal(t, int(blocksPerRequest)-int(forkedSlot-(forkedEpochStartSlot+1)), len(firstFSM.bwb))
+		require.Equal(t, int(blocksPerRequest)-int(forkedSlot-(forkedEpochStartSlot+1)), len(firstFSM.fetched.bwb))
 		for i := startSlot; i < startSlot.Add(blocksPerRequest*(lookaheadSteps-1)); i += primitives.Slot(blocksPerRequest) {
 			fsm, ok := queue.smm.findStateMachine(i)
 			require.Equal(t, true, ok)

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

@@ -24,8 +24,8 @@ func (q *blocksQueue) resetFromFork(fork *forkData) error {
 		return err
 	}
 	fsm := q.smm.addStateMachine(firstBlock.Slot())
-	fsm.pid = fork.peer
-	fsm.bwb = fork.bwb
+	fsm.fetched.bwb = fork.bwb
+	fsm.fetched.blocksFrom, fsm.fetched.blobsFrom = fork.blocksFrom, fork.blobsFrom
 	fsm.state = stateDataParsed
 
 	// The rest of machines are in skipped state.

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

@@ -0,0 +1,219 @@
+package initialsync
+
+import (
+	"context"
+	"testing"
+	"time"
+
+	"github.com/OffchainLabs/prysm/v6/beacon-chain/blockchain"
+	mock "github.com/OffchainLabs/prysm/v6/beacon-chain/blockchain/testing"
+	"github.com/OffchainLabs/prysm/v6/beacon-chain/p2p/peers/peerdata"
+	p2pt "github.com/OffchainLabs/prysm/v6/beacon-chain/p2p/testing"
+	"github.com/OffchainLabs/prysm/v6/beacon-chain/startup"
+	"github.com/OffchainLabs/prysm/v6/beacon-chain/sync"
+	"github.com/OffchainLabs/prysm/v6/beacon-chain/verification"
+	"github.com/OffchainLabs/prysm/v6/consensus-types/primitives"
+	"github.com/OffchainLabs/prysm/v6/testing/assert"
+	"github.com/OffchainLabs/prysm/v6/testing/require"
+	"github.com/libp2p/go-libp2p/core/peer"
+	"github.com/pkg/errors"
+)
+
+type testDownscorePeer int
+
+const (
+	testDownscoreNeither testDownscorePeer = iota
+	testDownscoreBlock
+	testDownscoreBlob
+)
+
+func peerIDForTestDownscore(w testDownscorePeer, name string) peer.ID {
+	switch w {
+	case testDownscoreBlock:
+		return peer.ID("block" + name)
+	case testDownscoreBlob:
+		return peer.ID("blob" + name)
+	default:
+		return ""
+	}
+}
+
+func TestUpdatePeerScorerStats(t *testing.T) {
+	cases := []struct {
+		name      string
+		err       error
+		processed uint64
+		downPeer  testDownscorePeer
+	}{
+		{
+			name:      "invalid block",
+			err:       blockchain.ErrInvalidPayload,
+			downPeer:  testDownscoreBlock,
+			processed: 10,
+		},
+		{
+			name:      "invalid blob",
+			err:       verification.ErrBlobIndexInvalid,
+			downPeer:  testDownscoreBlob,
+			processed: 3,
+		},
+		{
+			name:      "not validity error",
+			err:       errors.New("test"),
+			processed: 32,
+		},
+		{
+			name:      "no error",
+			processed: 32,
+		},
+	}
+	s := &Service{
+		cfg: &Config{
+			P2P: p2pt.NewTestP2P(t),
+		},
+	}
+	for _, c := range cases {
+		t.Run(c.name, func(t *testing.T) {
+			data := &blocksQueueFetchedData{
+				blocksFrom: peerIDForTestDownscore(testDownscoreBlock, c.name),
+				blobsFrom:  peerIDForTestDownscore(testDownscoreBlob, c.name),
+			}
+			s.updatePeerScorerStats(data, c.processed, c.err)
+			if c.err != nil && c.downPeer != testDownscoreNeither {
+				switch c.downPeer {
+				case testDownscoreBlock:
+					// block should be downscored
+					blocksCount, err := s.cfg.P2P.Peers().Scorers().BadResponsesScorer().Count(data.blocksFrom)
+					require.NoError(t, err)
+					require.Equal(t, 1, blocksCount)
+					// blob should not be downscored - also we expect a not found error since peer scoring did not interact with blobs
+					blobCount, err := s.cfg.P2P.Peers().Scorers().BadResponsesScorer().Count(data.blobsFrom)
+					require.ErrorIs(t, err, peerdata.ErrPeerUnknown)
+					require.Equal(t, -1, blobCount)
+				case testDownscoreBlob:
+					// block should not be downscored - also we expect a not found error since peer scoring did not interact with blocks
+					blocksCount, err := s.cfg.P2P.Peers().Scorers().BadResponsesScorer().Count(data.blocksFrom)
+					require.ErrorIs(t, err, peerdata.ErrPeerUnknown)
+					require.Equal(t, -1, blocksCount)
+					// blob should be downscored
+					blobCount, err := s.cfg.P2P.Peers().Scorers().BadResponsesScorer().Count(data.blobsFrom)
+					require.NoError(t, err)
+					require.Equal(t, 1, blobCount)
+				}
+				assert.Equal(t, uint64(0), s.cfg.P2P.Peers().Scorers().BlockProviderScorer().ProcessedBlocks(data.blocksFrom))
+				return
+			}
+			// block should not be downscored - also we expect a not found error since peer scoring did not interact with blocks
+			blocksCount, err := s.cfg.P2P.Peers().Scorers().BadResponsesScorer().Count(data.blocksFrom)
+			// The scorer will know about the the block peer because it will have a processed blocks count
+			require.NoError(t, err)
+			require.Equal(t, 0, blocksCount)
+			// no downscore, so scorer doesn't know the peer
+			blobCount, err := s.cfg.P2P.Peers().Scorers().BadResponsesScorer().Count(data.blobsFrom)
+			require.ErrorIs(t, err, peerdata.ErrPeerUnknown)
+			require.Equal(t, -1, blobCount)
+
+			assert.Equal(t, c.processed, s.cfg.P2P.Peers().Scorers().BlockProviderScorer().ProcessedBlocks(data.blocksFrom))
+		})
+	}
+}
+
+func TestOnDataReceivedDownscore(t *testing.T) {
+	cases := []struct {
+		name     string
+		err      error
+		downPeer testDownscorePeer
+	}{
+		{
+			name:     "invalid block",
+			err:      sync.ErrInvalidFetchedData,
+			downPeer: testDownscoreBlock,
+		},
+		{
+			name:     "invalid blob",
+			err:      errors.Wrap(verification.ErrBlobInvalid, "test"),
+			downPeer: testDownscoreBlob,
+		},
+		{
+			name: "not validity error",
+			err:  errors.New("test"),
+		},
+		{
+			name: "no error",
+		},
+	}
+	for _, c := range cases {
+		t.Run(c.name, func(t *testing.T) {
+			data := &fetchRequestResponse{
+				blocksFrom: peerIDForTestDownscore(testDownscoreBlock, c.name),
+				blobsFrom:  peerIDForTestDownscore(testDownscoreBlob, c.name),
+				err:        c.err,
+			}
+			if c.downPeer == testDownscoreBlob {
+				require.Equal(t, true, verification.IsBlobValidationFailure(c.err))
+			}
+			ctx := context.Background()
+			p2p := p2pt.NewTestP2P(t)
+			mc := &mock.ChainService{Genesis: time.Now(), ValidatorsRoot: [32]byte{}}
+			fetcher := newBlocksFetcher(ctx, &blocksFetcherConfig{
+				chain: mc,
+				p2p:   p2p,
+				clock: startup.NewClock(mc.Genesis, mc.ValidatorsRoot),
+			})
+			q := newBlocksQueue(ctx, &blocksQueueConfig{
+				p2p:                 p2p,
+				blocksFetcher:       fetcher,
+				highestExpectedSlot: primitives.Slot(32),
+				chain:               mc})
+			sm := q.smm.addStateMachine(0)
+			sm.state = stateScheduled
+			handle := q.onDataReceivedEvent(context.Background())
+			endState, err := handle(sm, data)
+			if c.err != nil {
+				require.ErrorIs(t, err, c.err)
+			} else {
+				require.NoError(t, err)
+			}
+			// state machine should stay in "scheduled" if there's an error
+			// and transition to "data parsed" if there's no error
+			if c.err != nil {
+				require.Equal(t, stateScheduled, endState)
+			} else {
+				require.Equal(t, stateDataParsed, endState)
+			}
+			if c.err != nil && c.downPeer != testDownscoreNeither {
+				switch c.downPeer {
+				case testDownscoreBlock:
+					// block should be downscored
+					blocksCount, err := p2p.Peers().Scorers().BadResponsesScorer().Count(data.blocksFrom)
+					require.NoError(t, err)
+					require.Equal(t, 1, blocksCount)
+					// blob should not be downscored - also we expect a not found error since peer scoring did not interact with blobs
+					blobCount, err := p2p.Peers().Scorers().BadResponsesScorer().Count(data.blobsFrom)
+					require.ErrorIs(t, err, peerdata.ErrPeerUnknown)
+					require.Equal(t, -1, blobCount)
+				case testDownscoreBlob:
+					// block should not be downscored - also we expect a not found error since peer scoring did not interact with blocks
+					blocksCount, err := p2p.Peers().Scorers().BadResponsesScorer().Count(data.blocksFrom)
+					require.ErrorIs(t, err, peerdata.ErrPeerUnknown)
+					require.Equal(t, -1, blocksCount)
+					// blob should be downscored
+					blobCount, err := p2p.Peers().Scorers().BadResponsesScorer().Count(data.blobsFrom)
+					require.NoError(t, err)
+					require.Equal(t, 1, blobCount)
+				}
+				assert.Equal(t, uint64(0), p2p.Peers().Scorers().BlockProviderScorer().ProcessedBlocks(data.blocksFrom))
+				return
+			}
+			// block should not be downscored - also we expect a not found error since peer scoring did not interact with blocks
+			blocksCount, err := p2p.Peers().Scorers().BadResponsesScorer().Count(data.blocksFrom)
+			// no downscore, so scorer doesn't know the peer
+			require.ErrorIs(t, err, peerdata.ErrPeerUnknown)
+			require.Equal(t, -1, blocksCount)
+			blobCount, err := p2p.Peers().Scorers().BadResponsesScorer().Count(data.blobsFrom)
+			// no downscore, so scorer doesn't know the peer
+			require.ErrorIs(t, err, peerdata.ErrPeerUnknown)
+			require.Equal(t, -1, blobCount)
+		})
+	}
+}

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

@@ -6,11 +6,9 @@ import (
 	"sort"
 	"time"
 
-	"github.com/OffchainLabs/prysm/v6/consensus-types/blocks"
 	"github.com/OffchainLabs/prysm/v6/consensus-types/primitives"
 	prysmTime "github.com/OffchainLabs/prysm/v6/time"
 	"github.com/OffchainLabs/prysm/v6/time/slots"
-	"github.com/libp2p/go-libp2p/core/peer"
 )
 
 const (
@@ -45,8 +43,7 @@ type stateMachine struct {
 	smm     *stateMachineManager
 	start   primitives.Slot
 	state   stateID
-	pid     peer.ID
-	bwb     []blocks.BlockWithROSidecars
+	fetched fetchRequestResponse
 	updated time.Time
 }
 
@@ -78,7 +75,7 @@ func (smm *stateMachineManager) addStateMachine(startSlot primitives.Slot) *stat
 		smm:     smm,
 		start:   startSlot,
 		state:   stateNew,
-		bwb:     []blocks.BlockWithROSidecars{},
+		fetched: fetchRequestResponse{},
 		updated: prysmTime.Now(),
 	}
 	smm.recalculateMachineAttribs()
@@ -90,7 +87,7 @@ func (smm *stateMachineManager) removeStateMachine(startSlot primitives.Slot) er
 	if _, ok := smm.machines[startSlot]; !ok {
 		return fmt.Errorf("state for machine %v is not found", startSlot)
 	}
-	smm.machines[startSlot].bwb = nil
+	smm.machines[startSlot].fetched = fetchRequestResponse{}
 	delete(smm.machines, startSlot)
 	smm.recalculateMachineAttribs()
 	return nil
@@ -187,6 +184,10 @@ func (m *stateMachine) isLast() bool {
 	return m.start == m.smm.keys[len(m.smm.keys)-1]
 }
 
+func (m *stateMachine) numFetched() int {
+	return len(m.fetched.bwb)
+}
+
 // String returns human-readable representation of a FSM state.
 func (m *stateMachine) String() string {
 	return fmt.Sprintf("{%d:%s}", slots.ToEpoch(m.start), m.state)

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

@@ -16,7 +16,6 @@ import (
 	"github.com/OffchainLabs/prysm/v6/consensus-types/primitives"
 	"github.com/OffchainLabs/prysm/v6/runtime/version"
 	"github.com/OffchainLabs/prysm/v6/time/slots"
-	"github.com/libp2p/go-libp2p/core/peer"
 	"github.com/paulbellamy/ratecounter"
 	"github.com/pkg/errors"
 	"github.com/sirupsen/logrus"
@@ -132,7 +131,7 @@ func (s *Service) syncToNonFinalizedEpoch(ctx context.Context) error {
 	}
 	for data := range queue.fetchedData {
 		count, err := s.processFetchedDataRegSync(ctx, data)
-		s.updatePeerScorerStats(data.pid, count, err)
+		s.updatePeerScorerStats(data, count, err)
 	}
 	log.WithFields(logrus.Fields{
 		"syncedSlot":  s.cfg.Chain.HeadSlot(),
@@ -152,7 +151,7 @@ func (s *Service) processFetchedData(ctx context.Context, data *blocksQueueFetch
 	if err != nil {
 		log.WithError(err).Warn("Skip processing batched blocks")
 	}
-	s.updatePeerScorerStats(data.pid, count, err)
+	s.updatePeerScorerStats(data, count, err)
 }
 
 // processFetchedDataRegSync processes data received from queue.
@@ -169,7 +168,7 @@ func (s *Service) processFetchedDataRegSync(ctx context.Context, data *blocksQue
 
 	nodeID := s.cfg.P2P.NodeID()
 
-	// Seperate blocks with blobs from blocks with data columns.
+	// Separate blocks with blobs from blocks with data columns.
 	fistDataColumnIndex := sort.Search(len(bwb), func(i int) bool {
 		return bwb[i].Block.Version() >= version.Fulu
 	})
@@ -372,7 +371,7 @@ func (s *Service) processBatchedBlocks(ctx context.Context, bwb []blocks.BlockWi
 			errParentDoesNotExist, firstBlock.Block().ParentRoot(), firstBlock.Block().Slot())
 	}
 
-	// Seperate blocks with blobs from blocks with data columns.
+	// Seaerate blocks with blobs from blocks with data columns.
 	fistDataColumnIndex := sort.Search(len(bwb), func(i int) bool {
 		return bwb[i].Block.Version() >= version.Fulu
 	})
@@ -455,18 +454,19 @@ func isPunishableError(err error) bool {
 }
 
 // updatePeerScorerStats adjusts monitored metrics for a peer.
-func (s *Service) updatePeerScorerStats(pid peer.ID, count uint64, err error) {
-	if pid == "" {
-		return
-	}
+func (s *Service) updatePeerScorerStats(data *blocksQueueFetchedData, count uint64, err error) {
 	if isPunishableError(err) {
-		log.WithError(err).WithField("peer_id", pid).Warn("Incrementing peers bad response count")
-		s.cfg.P2P.Peers().Scorers().BadResponsesScorer().Increment(pid)
+		if verification.IsBlobValidationFailure(err) {
+			log.WithError(err).WithField("peer_id", data.blobsFrom).Warn("Downscoring peer for invalid blobs")
+			s.cfg.P2P.Peers().Scorers().BadResponsesScorer().Increment(data.blobsFrom)
+		} else {
+			log.WithError(err).WithField("peer_id", data.blocksFrom).Warn("Downscoring peer for invalid blocks")
+			s.cfg.P2P.Peers().Scorers().BadResponsesScorer().Increment(data.blocksFrom)
+		}
 		// If the error is punishable, exit here so that we don't give them credit for providing bad blocks.
 		return
 	}
-	scorer := s.cfg.P2P.Peers().Scorers().BlockProviderScorer()
-	scorer.IncrementProcessedBlocks(pid, count)
+	s.cfg.P2P.Peers().Scorers().BlockProviderScorer().IncrementProcessedBlocks(data.blocksFrom, count)
 }
 
 // isProcessedBlock checks DB and local cache for presence of a given block, to avoid duplicates.

beacon-chain/sync/rpc_blob_sidecars_by_root_test.go

@@ -156,7 +156,7 @@ func readChunkEncodedBlobsLowMax(t *testing.T, s *Service, expect []*expectedBlo
 	}
 	return func(stream network.Stream) {
 		_, err := readChunkEncodedBlobs(stream, encoding, ctxMap, vf, 1)
-		require.ErrorIs(t, err, ErrInvalidFetchedData)
+		require.ErrorIs(t, err, errMaxRequestBlobSidecarsExceeded)
 	}
 }
 

beacon-chain/sync/rpc_send_request_test.go

@@ -12,6 +12,7 @@ import (
 	p2ptest "github.com/OffchainLabs/prysm/v6/beacon-chain/p2p/testing"
 	p2pTypes "github.com/OffchainLabs/prysm/v6/beacon-chain/p2p/types"
 	"github.com/OffchainLabs/prysm/v6/beacon-chain/startup"
+	"github.com/OffchainLabs/prysm/v6/beacon-chain/verification"
 	fieldparams "github.com/OffchainLabs/prysm/v6/config/fieldparams"
 	"github.com/OffchainLabs/prysm/v6/config/params"
 	"github.com/OffchainLabs/prysm/v6/consensus-types/blocks"
@@ -877,3 +878,7 @@ func TestSendBlobsByRangeRequest(t *testing.T) {
 		assert.Equal(t, int(totalElectraBlobs), len(blobs))
 	})
 }
+
+func TestErrInvalidFetchedDataDistinction(t *testing.T) {
+	require.Equal(t, false, errors.Is(ErrInvalidFetchedData, verification.ErrBlobInvalid))
+}

beacon-chain/sync/subscriber.go

@@ -365,10 +365,9 @@ func (s *Service) wrapAndReportValidation(topic string, v wrappedVal) (string, p
 	}
 }
 
-// reValidateSubscriptions unsubscribe from topics we are currently subscribed to but that are
+// pruneSubscriptions unsubscribe from topics we are currently subscribed to but that are
 // not in the list of wanted subnets.
-// TODO: Rename this functions as it does not only revalidate subscriptions.
-func (s *Service) reValidateSubscriptions(
+func (s *Service) pruneSubscriptions(
 	subscriptions map[uint64]*pubsub.Subscription,
 	wantedSubs []uint64,
 	topicFormat string,
@@ -467,7 +466,7 @@ func (s *Service) subscribeToSubnets(
 			"digest":  fmt.Sprintf("%#x", digest),
 			"subnets": description,
 		}).Debug("Subnets with this digest are no longer valid, unsubscribing from all of them")
-		s.reValidateSubscriptions(subscriptions, []uint64{}, topicFormat, digest)
+		s.pruneSubscriptions(subscriptions, []uint64{}, topicFormat, digest)
 		return false
 	}
 
@@ -475,7 +474,7 @@ func (s *Service) subscribeToSubnets(
 	subnetsToSubscribeIndex := getSubnetsToSubscribe(currentSlot)
 
 	// Remove subscriptions that are no longer wanted.
-	s.reValidateSubscriptions(subscriptions, subnetsToSubscribeIndex, topicFormat, digest)
+	s.pruneSubscriptions(subscriptions, subnetsToSubscribeIndex, topicFormat, digest)
 
 	// Subscribe to wanted subnets.
 	for _, subnetIndex := range subnetsToSubscribeIndex {

beacon-chain/sync/subscriber_beacon_blocks.go

@@ -15,6 +15,7 @@ import (
 	"github.com/OffchainLabs/prysm/v6/io/file"
 	"github.com/OffchainLabs/prysm/v6/runtime/version"
 	"github.com/OffchainLabs/prysm/v6/time/slots"
+	"github.com/sirupsen/logrus"
 	"google.golang.org/protobuf/proto"
 )
 
@@ -78,6 +79,11 @@ func (s *Service) reconstructAndBroadcastSidecars(ctx context.Context, block int
 func (s *Service) reconstructAndBroadcastDataColumnSidecars(ctx context.Context, roSignedBlock interfaces.ReadOnlySignedBeaconBlock) {
 	block := roSignedBlock.Block()
 
+	log := log.WithFields(logrus.Fields{
+		"slot":          block.Slot(),
+		"proposerIndex": block.ProposerIndex(),
+	})
+
 	kzgCommitments, err := block.Body().BlobKzgCommitments()
 	if err != nil {
 		log.WithError(err).Error("Failed to read commitments from block")
@@ -95,6 +101,8 @@ func (s *Service) reconstructAndBroadcastDataColumnSidecars(ctx context.Context,
 		return
 	}
 
+	log = log.WithField("blockRoot", fmt.Sprintf("%#x", blockRoot))
+
 	if s.cfg.dataColumnStorage == nil {
 		log.Warning("Data column storage is not enabled, skip saving data column, but continue to reconstruct and broadcast data column")
 	}
@@ -106,6 +114,11 @@ func (s *Service) reconstructAndBroadcastDataColumnSidecars(ctx context.Context,
 		return
 	}
 
+	// Return early if no blobs are retrieved from the EL.
+	if len(sidecars) == 0 {
+		return
+	}
+
 	nodeID := s.cfg.p2p.NodeID()
 
 	s.cfg.custodyInfo.Mut.RLock()
@@ -124,8 +137,9 @@ func (s *Service) reconstructAndBroadcastDataColumnSidecars(ctx context.Context,
 	// Broadcast and save data columns sidecars to custody but not yet received.
 	sidecarCount := uint64(len(sidecars))
 	for columnIndex := range info.CustodyColumns {
+		log := log.WithField("columnIndex", columnIndex)
 		if columnIndex >= sidecarCount {
-			log.WithField("index", columnIndex).Error("Sidecar index out of range - should never happen")
+			log.Error("Column custody index out of range - should never happen")
 			continue
 		}
 
@@ -136,11 +150,11 @@ func (s *Service) reconstructAndBroadcastDataColumnSidecars(ctx context.Context,
 		sidecar := sidecars[columnIndex]
 
 		if err := s.cfg.p2p.BroadcastDataColumn(ctx, blockRoot, sidecar.Index, sidecar.DataColumnSidecar); err != nil {
-			log.WithFields(dataColumnFields(sidecar.RODataColumn)).WithError(err).Error("Failed to broadcast data column")
+			log.WithError(err).Error("Failed to broadcast data column")
 		}
 
 		if err := s.receiveDataColumn(ctx, sidecar); err != nil {
-			log.WithFields(dataColumnFields(sidecar.RODataColumn)).WithError(err).Error("Failed to receive data column")
+			log.WithError(err).Error("Failed to receive data column")
 		}
 	}
 }

beacon-chain/sync/subscriber_test.go

@@ -308,7 +308,7 @@ func TestRevalidateSubscription_CorrectlyFormatsTopic(t *testing.T) {
 	subscriptions[2], err = r.cfg.p2p.SubscribeToTopic(fullTopic)
 	require.NoError(t, err)
 
-	r.reValidateSubscriptions(subscriptions, []uint64{2}, defaultTopic, digest)
+	r.pruneSubscriptions(subscriptions, []uint64{2}, defaultTopic, digest)
 	require.LogsDoNotContain(t, hook, "Could not unregister topic validator")
 }
 

beacon-chain/sync/validate_beacon_blocks.go

@@ -21,6 +21,7 @@ import (
 	"github.com/OffchainLabs/prysm/v6/encoding/bytesutil"
 	"github.com/OffchainLabs/prysm/v6/monitoring/tracing"
 	"github.com/OffchainLabs/prysm/v6/monitoring/tracing/trace"
+	ethpb "github.com/OffchainLabs/prysm/v6/proto/prysm/v1alpha1"
 	"github.com/OffchainLabs/prysm/v6/runtime/version"
 	prysmTime "github.com/OffchainLabs/prysm/v6/time"
 	"github.com/OffchainLabs/prysm/v6/time/slots"
@@ -31,8 +32,9 @@ import (
 )
 
 var (
-	ErrOptimisticParent    = errors.New("parent of the block is optimistic")
-	errRejectCommitmentLen = errors.New("[REJECT] The length of KZG commitments is less than or equal to the limitation defined in Consensus Layer")
+	ErrOptimisticParent         = errors.New("parent of the block is optimistic")
+	errRejectCommitmentLen      = errors.New("[REJECT] The length of KZG commitments is less than or equal to the limitation defined in Consensus Layer")
+	ErrSlashingSignatureFailure = errors.New("proposer slashing signature verification failed")
 )
 
 // validateBeaconBlockPubSub checks that the incoming block has a valid BLS signature.
@@ -109,6 +111,16 @@ func (s *Service) validateBeaconBlockPubSub(ctx context.Context, pid peer.ID, ms
 
 	// Verify the block is the first block received for the proposer for the slot.
 	if s.hasSeenBlockIndexSlot(blk.Block().Slot(), blk.Block().ProposerIndex()) {
+		// Attempt to detect and broadcast equivocation before ignoring
+		err = s.detectAndBroadcastEquivocation(ctx, blk)
+		if err != nil {
+			// If signature verification fails, reject the block
+			if errors.Is(err, ErrSlashingSignatureFailure) {
+				return pubsub.ValidationReject, err
+			}
+			// In case there is some other error log but don't reject
+			log.WithError(err).Debug("Could not detect/broadcast equivocation")
+		}
 		return pubsub.ValidationIgnore, nil
 	}
 
@@ -469,3 +481,74 @@ func getBlockFields(b interfaces.ReadOnlySignedBeaconBlock) logrus.Fields {
 		"version":       b.Block().Version(),
 	}
 }
+
+// detectAndBroadcastEquivocation checks if the given block is an equivocating block by comparing it with
+// the head block. If the blocks are from the same slot and proposer but have different signatures,
+// it creates and broadcasts a proposer slashing object after verification.
+func (s *Service) detectAndBroadcastEquivocation(ctx context.Context, blk interfaces.ReadOnlySignedBeaconBlock) error {
+	slot := blk.Block().Slot()
+	proposerIndex := blk.Block().ProposerIndex()
+
+	// Get head block for comparison
+	headBlock, err := s.cfg.chain.HeadBlock(ctx)
+	if err != nil {
+		return errors.Wrap(err, "could not get head block")
+	}
+
+	// Only proceed if this block is from same slot and proposer as head
+	if headBlock.Block().Slot() != slot || headBlock.Block().ProposerIndex() != proposerIndex {
+		return nil
+	}
+
+	// Compare signatures
+	sig1 := blk.Signature()
+	sig2 := headBlock.Signature()
+
+	// If signatures match, these are the same block
+	if sig1 == sig2 {
+		return nil
+	}
+
+	// Extract headers for slashing
+	header1, err := blk.Header()
+	if err != nil {
+		return errors.Wrap(err, "could not get header from new block")
+	}
+	header2, err := headBlock.Header()
+	if err != nil {
+		return errors.Wrap(err, "could not get header from head block")
+	}
+
+	slashing := &ethpb.ProposerSlashing{
+		Header_1: header1,
+		Header_2: header2,
+	}
+
+	// Get state for verification
+	headState, err := s.cfg.chain.HeadStateReadOnly(ctx)
+	if err != nil {
+		return errors.Wrap(err, "could not get head state")
+	}
+
+	// Verify the slashing against current state
+	if err := blocks.VerifyProposerSlashing(headState, slashing); err != nil {
+		if errors.Is(err, blocks.ErrCouldNotVerifyBlockHeader) {
+			return errors.Wrap(ErrSlashingSignatureFailure, err.Error())
+		}
+		return errors.Wrap(err, "could not verify proposer slashing")
+	}
+
+	// Broadcast if verification passes
+	if !features.Get().DisableBroadcastSlashings {
+		if err := s.cfg.p2p.Broadcast(ctx, slashing); err != nil {
+			return errors.Wrap(err, "could not broadcast slashing object")
+		}
+	}
+
+	// Insert into slashing pool
+	if err := s.cfg.slashingPool.InsertProposerSlashing(ctx, headState, slashing); err != nil {
+		return errors.Wrap(err, "could not insert proposer slashing into pool")
+	}
+
+	return nil
+}

beacon-chain/sync/validate_beacon_blocks_test.go

@@ -18,6 +18,7 @@ import (
 	dbtest "github.com/OffchainLabs/prysm/v6/beacon-chain/db/testing"
 	doublylinkedtree "github.com/OffchainLabs/prysm/v6/beacon-chain/forkchoice/doubly-linked-tree"
 	"github.com/OffchainLabs/prysm/v6/beacon-chain/operations/attestations"
+	slashingsmock "github.com/OffchainLabs/prysm/v6/beacon-chain/operations/slashings/mock"
 	"github.com/OffchainLabs/prysm/v6/beacon-chain/p2p"
 	p2ptest "github.com/OffchainLabs/prysm/v6/beacon-chain/p2p/testing"
 	"github.com/OffchainLabs/prysm/v6/beacon-chain/startup"
@@ -713,8 +714,21 @@ func TestValidateBeaconBlockPubSub_SeenProposerSlot(t *testing.T) {
 	msg.Signature, err = signing.ComputeDomainAndSign(beaconState, 0, msg.Block, params.BeaconConfig().DomainBeaconProposer, privKeys[proposerIdx])
 	require.NoError(t, err)
 
-	chainService := &mock.ChainService{Genesis: time.Unix(time.Now().Unix()-int64(params.BeaconConfig().SecondsPerSlot), 0),
-		State: beaconState,
+	// Create a clone of the same block (same signature, not an equivocation)
+	msgClone := util.NewBeaconBlock()
+	msgClone.Block.Slot = 1
+	msgClone.Block.ProposerIndex = proposerIdx
+	msgClone.Block.ParentRoot = bRoot[:]
+	msgClone.Signature = msg.Signature // Use the same signature
+
+	signedBlock, err := blocks.NewSignedBeaconBlock(msg)
+	require.NoError(t, err)
+
+	slashingPool := &slashingsmock.PoolMock{}
+	chainService := &mock.ChainService{
+		Genesis: time.Unix(time.Now().Unix()-int64(params.BeaconConfig().SecondsPerSlot), 0),
+		State:   beaconState,
+		Block:   signedBlock, // Set the first block as the head block
 		FinalizedCheckPoint: &ethpb.Checkpoint{
 			Epoch: 0,
 			Root:  make([]byte, 32),
@@ -728,6 +742,7 @@ func TestValidateBeaconBlockPubSub_SeenProposerSlot(t *testing.T) {
 			chain:         chainService,
 			clock:         startup.NewClock(chainService.Genesis, chainService.ValidatorsRoot),
 			blockNotifier: chainService.BlockNotifier(),
+			slashingPool:  slashingPool,
 		},
 		seenBlockCache:      lruwrpr.New(10),
 		badBlockCache:       lruwrpr.New(10),
@@ -735,10 +750,15 @@ func TestValidateBeaconBlockPubSub_SeenProposerSlot(t *testing.T) {
 		seenPendingBlocks:   make(map[[32]byte]bool),
 	}
 
+	// Mark the proposer/slot as seen
+	r.setSeenBlockIndexSlot(msg.Block.Slot, msg.Block.ProposerIndex)
+	time.Sleep(10 * time.Millisecond) // Wait for cached value to pass through buffers
+
+	// Prepare and validate the second message (clone)
 	buf := new(bytes.Buffer)
-	_, err = p.Encoding().EncodeGossip(buf, msg)
+	_, err = p.Encoding().EncodeGossip(buf, msgClone)
 	require.NoError(t, err)
-	topic := p2p.GossipTypeMapping[reflect.TypeOf(msg)]
+	topic := p2p.GossipTypeMapping[reflect.TypeOf(msgClone)]
 	digest, err := r.currentForkDigest()
 	assert.NoError(t, err)
 	topic = r.addDigestToTopic(topic, digest)
@@ -748,11 +768,14 @@ func TestValidateBeaconBlockPubSub_SeenProposerSlot(t *testing.T) {
 			Topic: &topic,
 		},
 	}
-	r.setSeenBlockIndexSlot(msg.Block.Slot, msg.Block.ProposerIndex)
-	time.Sleep(10 * time.Millisecond) // Wait for cached value to pass through buffers.
+
+	// Since this is not an equivocation (same signature), it should be ignored
 	res, err := r.validateBeaconBlockPubSub(ctx, "", m)
 	assert.NoError(t, err)
-	assert.Equal(t, res, pubsub.ValidationIgnore, "seen proposer block should be ignored")
+	assert.Equal(t, pubsub.ValidationIgnore, res, "block with same signature should be ignored")
+
+	// Verify no slashings were created
+	assert.Equal(t, 0, len(slashingPool.PendingPropSlashings), "Expected no slashings for same signature")
 }
 
 func TestValidateBeaconBlockPubSub_FilterByFinalizedEpoch(t *testing.T) {
@@ -1495,3 +1518,218 @@ func Test_validateDenebBeaconBlock(t *testing.T) {
 	require.NoError(t, err)
 	require.ErrorIs(t, validateDenebBeaconBlock(bdb.Block()), errRejectCommitmentLen)
 }
+
+func TestDetectAndBroadcastEquivocation(t *testing.T) {
+	ctx := context.Background()
+	p := p2ptest.NewTestP2P(t)
+	beaconState, privKeys := util.DeterministicGenesisState(t, 100)
+
+	t.Run("no equivocation", func(t *testing.T) {
+		block := util.NewBeaconBlock()
+		block.Block.Slot = 1
+		block.Block.ProposerIndex = 0
+
+		sig, err := signing.ComputeDomainAndSign(beaconState, 0, block.Block, params.BeaconConfig().DomainBeaconProposer, privKeys[0])
+		require.NoError(t, err)
+		block.Signature = sig
+
+		// Create head block with different slot/proposer
+		headBlock := util.NewBeaconBlock()
+		headBlock.Block.Slot = 2          // Different slot
+		headBlock.Block.ProposerIndex = 1 // Different proposer
+		signedHeadBlock, err := blocks.NewSignedBeaconBlock(headBlock)
+		require.NoError(t, err)
+
+		chainService := &mock.ChainService{
+			State:   beaconState,
+			Genesis: time.Now(),
+			Block:   signedHeadBlock,
+		}
+
+		slashingPool := &slashingsmock.PoolMock{}
+		r := &Service{
+			cfg: &config{
+				p2p:          p,
+				chain:        chainService,
+				slashingPool: slashingPool,
+			},
+			seenBlockCache: lruwrpr.New(10),
+		}
+
+		signedBlock, err := blocks.NewSignedBeaconBlock(block)
+		require.NoError(t, err)
+
+		err = r.detectAndBroadcastEquivocation(ctx, signedBlock)
+		require.NoError(t, err)
+		assert.Equal(t, 0, len(slashingPool.PendingPropSlashings), "Expected no slashings")
+	})
+
+	t.Run("equivocation detected", func(t *testing.T) {
+		// Create head block
+		headBlock := util.NewBeaconBlock()
+		headBlock.Block.Slot = 1
+		headBlock.Block.ProposerIndex = 0
+		headBlock.Block.ParentRoot = bytesutil.PadTo([]byte("parent1"), 32)
+		sig1, err := signing.ComputeDomainAndSign(beaconState, 0, headBlock.Block, params.BeaconConfig().DomainBeaconProposer, privKeys[0])
+		require.NoError(t, err)
+		headBlock.Signature = sig1
+
+		// Create second block with same slot/proposer but different contents
+		newBlock := util.NewBeaconBlock()
+		newBlock.Block.Slot = 1
+		newBlock.Block.ProposerIndex = 0
+		newBlock.Block.ParentRoot = bytesutil.PadTo([]byte("parent2"), 32)
+		sig2, err := signing.ComputeDomainAndSign(beaconState, 0, newBlock.Block, params.BeaconConfig().DomainBeaconProposer, privKeys[0])
+		require.NoError(t, err)
+		newBlock.Signature = sig2
+
+		signedHeadBlock, err := blocks.NewSignedBeaconBlock(headBlock)
+		require.NoError(t, err)
+
+		slashingPool := &slashingsmock.PoolMock{}
+		chainService := &mock.ChainService{
+			State:   beaconState,
+			Genesis: time.Now(),
+			Block:   signedHeadBlock,
+		}
+
+		r := &Service{
+			cfg: &config{
+				p2p:          p,
+				chain:        chainService,
+				slashingPool: slashingPool,
+			},
+			seenBlockCache: lruwrpr.New(10),
+		}
+
+		signedNewBlock, err := blocks.NewSignedBeaconBlock(newBlock)
+		require.NoError(t, err)
+
+		err = r.detectAndBroadcastEquivocation(ctx, signedNewBlock)
+		require.NoError(t, err)
+
+		// Verify slashing was inserted
+		require.Equal(t, 1, len(slashingPool.PendingPropSlashings), "Expected a slashing to be inserted")
+		slashing := slashingPool.PendingPropSlashings[0]
+		assert.Equal(t, primitives.ValidatorIndex(0), slashing.Header_1.Header.ProposerIndex, "Wrong proposer index")
+		assert.Equal(t, primitives.Slot(1), slashing.Header_1.Header.Slot, "Wrong slot")
+	})
+
+	t.Run("same signature", func(t *testing.T) {
+		// Create block
+		block := util.NewBeaconBlock()
+		block.Block.Slot = 1
+		block.Block.ProposerIndex = 0
+		sig, err := signing.ComputeDomainAndSign(beaconState, 0, block.Block, params.BeaconConfig().DomainBeaconProposer, privKeys[0])
+		require.NoError(t, err)
+		block.Signature = sig
+
+		signedBlock, err := blocks.NewSignedBeaconBlock(block)
+		require.NoError(t, err)
+
+		slashingPool := &slashingsmock.PoolMock{}
+		chainService := &mock.ChainService{
+			State:   beaconState,
+			Genesis: time.Now(),
+			Block:   signedBlock,
+		}
+
+		r := &Service{
+			cfg: &config{
+				p2p:          p,
+				chain:        chainService,
+				slashingPool: slashingPool,
+			},
+			seenBlockCache: lruwrpr.New(10),
+		}
+
+		err = r.detectAndBroadcastEquivocation(ctx, signedBlock)
+		require.NoError(t, err)
+		assert.Equal(t, 0, len(slashingPool.PendingPropSlashings), "Expected no slashings for same signature")
+	})
+
+	t.Run("head state error", func(t *testing.T) {
+		block := util.NewBeaconBlock()
+		block.Block.Slot = 1
+		block.Block.ProposerIndex = 0
+		block.Block.ParentRoot = bytesutil.PadTo([]byte("parent1"), 32)
+		sig1, err := signing.ComputeDomainAndSign(beaconState, 0, block.Block, params.BeaconConfig().DomainBeaconProposer, privKeys[0])
+		require.NoError(t, err)
+		block.Signature = sig1
+
+		headBlock := util.NewBeaconBlock()
+		headBlock.Block.Slot = 1                                            // Same slot
+		headBlock.Block.ProposerIndex = 0                                   // Same proposer
+		headBlock.Block.ParentRoot = bytesutil.PadTo([]byte("parent2"), 32) // Different parent root
+		sig2, err := signing.ComputeDomainAndSign(beaconState, 0, headBlock.Block, params.BeaconConfig().DomainBeaconProposer, privKeys[0])
+		require.NoError(t, err)
+		headBlock.Signature = sig2
+
+		signedBlock, err := blocks.NewSignedBeaconBlock(block)
+		require.NoError(t, err)
+
+		signedHeadBlock, err := blocks.NewSignedBeaconBlock(headBlock)
+		require.NoError(t, err)
+
+		chainService := &mock.ChainService{
+			State:        nil,
+			Block:        signedHeadBlock,
+			HeadStateErr: errors.New("could not get head state"),
+		}
+
+		r := &Service{
+			cfg: &config{
+				p2p:          p,
+				chain:        chainService,
+				slashingPool: &slashingsmock.PoolMock{},
+			},
+			seenBlockCache: lruwrpr.New(10),
+		}
+
+		err = r.detectAndBroadcastEquivocation(ctx, signedBlock)
+		require.ErrorContains(t, "could not get head state", err)
+	})
+	t.Run("signature verification failure", func(t *testing.T) {
+		// Create head block
+		headBlock := util.NewBeaconBlock()
+		headBlock.Block.Slot = 1
+		headBlock.Block.ProposerIndex = 0
+		sig1, err := signing.ComputeDomainAndSign(beaconState, 0, headBlock.Block, params.BeaconConfig().DomainBeaconProposer, privKeys[0])
+		require.NoError(t, err)
+		headBlock.Signature = sig1
+
+		// Create test block with invalid signature
+		newBlock := util.NewBeaconBlock()
+		newBlock.Block.Slot = 1
+		newBlock.Block.ProposerIndex = 0
+		newBlock.Block.ParentRoot = bytesutil.PadTo([]byte("different"), 32)
+		// generate invalid signature
+		invalidSig := make([]byte, 96)
+		copy(invalidSig, []byte("invalid signature"))
+		newBlock.Signature = invalidSig
+
+		signedHeadBlock, err := blocks.NewSignedBeaconBlock(headBlock)
+		require.NoError(t, err)
+		signedNewBlock, err := blocks.NewSignedBeaconBlock(newBlock)
+		require.NoError(t, err)
+
+		slashingPool := &slashingsmock.PoolMock{}
+		chainService := &mock.ChainService{
+			State:   beaconState,
+			Genesis: time.Now(),
+			Block:   signedHeadBlock,
+		}
+
+		r := &Service{
+			cfg: &config{
+				p2p:          p,
+				chain:        chainService,
+				slashingPool: slashingPool,
+			},
+			seenBlockCache: lruwrpr.New(10),
+		}
+
+		err = r.detectAndBroadcastEquivocation(ctx, signedNewBlock)
+		require.ErrorIs(t, err, ErrSlashingSignatureFailure)
+	})
+}

beacon-chain/sync/validate_blob.go

@@ -169,15 +169,6 @@ func blobFields(b blocks.ROBlob) logrus.Fields {
 	}
 }
 
-func dataColumnFields(b blocks.RODataColumn) logrus.Fields {
-	return logrus.Fields{
-		"slot":          b.Slot(),
-		"proposerIndex": b.ProposerIndex(),
-		"blockRoot":     fmt.Sprintf("%#x", b.BlockRoot()),
-		"columnIndex":   b.Index,
-	}
-}
-
 func computeSubnetForBlobSidecar(index uint64, slot primitives.Slot) uint64 {
 	subnetCount := params.BeaconConfig().BlobsidecarSubnetCount
 	if slots.ToEpoch(slot) >= params.BeaconConfig().ElectraForkEpoch {

beacon-chain/sync/validate_data_column.go

@@ -106,11 +106,6 @@ func (s *Service) validateDataColumn(ctx context.Context, pid peer.ID, msg *pubs
 		return pubsub.ValidationIgnore, err
 	}
 
-	// [REJECT] The proposer signature of `sidecar.signed_block_header`, is valid with respect to the `block_header.proposer_index` pubkey.
-	if err := verifier.ValidProposerSignature(ctx); err != nil {
-		return pubsub.ValidationReject, err
-	}
-
 	// [IGNORE] The sidecar's block's parent (defined by `block_header.parent_root`) has been seen (via gossip or non-gossip sources
 	// (a client MAY queue sidecars for processing once the parent block is retrieved).
 	if err := verifier.SidecarParentSeen(s.hasBadBlock); err != nil {
@@ -133,6 +128,13 @@ func (s *Service) validateDataColumn(ctx context.Context, pid peer.ID, msg *pubs
 		return pubsub.ValidationReject, err
 	}
 
+	// [REJECT] The proposer signature of `sidecar.signed_block_header`, is valid with respect to the `block_header.proposer_index` pubkey.
+	//          We do not strictly respect the spec ordering here. This is necessary because signature verification depends on the parent root,
+	//          which is only available if the parent block is known.
+	if err := verifier.ValidProposerSignature(ctx); err != nil {
+		return pubsub.ValidationReject, err
+	}
+
 	// [REJECT] The sidecar is from a higher slot than the sidecar's block's parent (defined by `block_header.parent_root`).
 	if err := verifier.SidecarParentSlotLower(); err != nil {
 		return pubsub.ValidationReject, err

beacon-chain/sync/validators_custody.go

@@ -35,14 +35,14 @@ func (s *Service) setTargetValidatorsCustodyRequirement() {
 	}
 
 	// Retrieve the head state.
-	headState, err := s.cfg.chain.HeadStateReadOnly(s.ctx)
-	if err != nil || headState == nil {
-		log.WithError(err).Error("Failed to get head state")
+	finalizedState := s.cfg.stateGen.FinalizedState()
+	if finalizedState == nil || finalizedState.IsNil() {
+		log.Error("Finalized state is nil")
 		return
 	}
 
 	// Get the validators custody requirement.
-	validatorsCustodyRequirement, err := peerdas.ValidatorsCustodyRequirement(headState, indices)
+	validatorsCustodyRequirement, err := peerdas.ValidatorsCustodyRequirement(finalizedState, indices)
 	if err != nil {
 		log.WithError(err).Error("Failed to get validators custody requirement")
 		return

beacon-chain/sync/validators_custody_test.go

@@ -1,10 +1,8 @@
 package sync
 
 import (
-	"context"
 	"testing"
 
-	mock "github.com/OffchainLabs/prysm/v6/beacon-chain/blockchain/testing"
 	"github.com/OffchainLabs/prysm/v6/beacon-chain/cache"
 	"github.com/OffchainLabs/prysm/v6/beacon-chain/core/peerdas"
 	testDB "github.com/OffchainLabs/prysm/v6/beacon-chain/db/testing"
@@ -102,21 +100,18 @@ func TestSetTargetValidatorsCustodyRequirement(t *testing.T) {
 
 	for _, tc := range testCases {
 		t.Run(tc.name, func(t *testing.T) {
-			ctx := context.Background()
 			beaconDB := testDB.SetupDB(t)
 			stateGen := stategen.New(beaconDB, doublylinkedtree.New())
 			state, _ := util.DeterministicGenesisState(t, 32)
 			err := state.SetBalances(tc.validatorsBalance)
 			require.NoError(t, err)
-			err = stateGen.SaveState(ctx, [32]byte{}, state)
-			require.NoError(t, err)
+
+			stateGen.SaveFinalizedState(0, [32]byte{}, state)
 
 			service := &Service{
 				trackedValidatorsCache: cache.NewTrackedValidatorsCache(),
 				cfg: &config{
-					chain: &mock.ChainService{
-						State: state,
-					},
+					stateGen:    stateGen,
 					custodyInfo: &peerdas.CustodyInfo{},
 				},
 			}