zip only json

* Attest timely by default

* Fix deprecated flag naming

api/server/middleware/BUILD.bazel

@@ -9,6 +9,7 @@ go_library(
     importpath = "github.com/OffchainLabs/prysm/v6/api/server/middleware",
     visibility = ["//visibility:public"],
     deps = [
+        "//api:go_default_library",
         "@com_github_rs_cors//:go_default_library",
         "@com_github_sirupsen_logrus//:go_default_library",
     ],

api/server/middleware/middleware.go

@@ -3,10 +3,10 @@ package middleware
 import (
 	"compress/gzip"
 	"fmt"
-	"io"
 	"net/http"
 	"strings"
 
+	"github.com/OffchainLabs/prysm/v6/api"
 	"github.com/rs/cors"
 	log "github.com/sirupsen/logrus"
 )
@@ -119,33 +119,40 @@ func AcceptHeaderHandler(serverAcceptedTypes []string) Middleware {
 func AcceptEncodingHeaderHandler() Middleware {
 	return func(next http.Handler) http.Handler {
 		return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
-			if !strings.Contains(r.Header.Get("Accept-Encoding"), "gzip") || strings.Contains(r.Header.Get("Accept"), "application/octet-stream") {
+			if !strings.Contains(r.Header.Get("Accept-Encoding"), "gzip") {
 				next.ServeHTTP(w, r)
 				return
 			}
 
-			w.Header().Set("Content-Encoding", "gzip")
-
 			gz := gzip.NewWriter(w)
+			gzipRW := &gzipResponseWriter{gz: gz, ResponseWriter: w}
 			defer func() {
+				if !gzipRW.zipped {
+					return
+				}
 				if err := gz.Close(); err != nil {
 					log.WithError(err).Error("Failed to close gzip writer")
 				}
 			}()
 
-			gzipRW := gzipResponseWriter{Writer: gz, ResponseWriter: w}
 			next.ServeHTTP(gzipRW, r)
 		})
 	}
 }
 
 type gzipResponseWriter struct {
-	io.Writer
+	gz *gzip.Writer
 	http.ResponseWriter
+	zipped bool
 }
 
-func (g gzipResponseWriter) Write(b []byte) (int, error) {
-	return g.Writer.Write(b)
+func (g *gzipResponseWriter) Write(b []byte) (int, error) {
+	if strings.Contains(g.Header().Get("Content-Type"), api.JsonMediaType) {
+		g.zipped = true
+		g.Header().Set("Content-Encoding", "gzip")
+		return g.gz.Write(b)
+	}
+	return g.ResponseWriter.Write(b)
 }
 
 func MiddlewareChain(h http.Handler, mw []Middleware) http.Handler {

api/server/middleware/middleware_test.go

@@ -2,16 +2,15 @@ package middleware
 
 import (
 	"bytes"
+	"compress/gzip"
+	"io"
 	"net/http"
 	"net/http/httptest"
 	"testing"
 
-	"compress/gzip"
-	"io"
-	log "github.com/sirupsen/logrus"
 	"github.com/OffchainLabs/prysm/v6/api"
 	"github.com/OffchainLabs/prysm/v6/testing/require"
-
+	log "github.com/sirupsen/logrus"
 )
 
 func TestNormalizeQueryValuesHandler(t *testing.T) {
@@ -130,9 +129,9 @@ func TestContentTypeHandler(t *testing.T) {
 }
 
 func TestAcceptEncodingHeaderHandler(t *testing.T) {
-
 	dummyContent := "Test gzip middleware content"
 	nextHandler := http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		w.Header().Set("Content-Type", r.Header.Get("Accept"))
 		_, err := w.Write([]byte(dummyContent))
 		require.NoError(t, err)
 	})
@@ -141,34 +140,46 @@ func TestAcceptEncodingHeaderHandler(t *testing.T) {
 
 	tests := []struct {
 		name             string
+		accept           string
 		acceptEncoding   string
 		expectCompressed bool
 	}{
 		{
 			name:             "Gzip supported",
+			accept:           api.JsonMediaType,
 			acceptEncoding:   "gzip",
 			expectCompressed: true,
 		},
 		{
 			name:             "Multiple encodings supported",
+			accept:           api.JsonMediaType,
 			acceptEncoding:   "deflate, gzip",
 			expectCompressed: true,
 		},
 		{
 			name:             "Gzip not supported",
+			accept:           api.JsonMediaType,
 			acceptEncoding:   "deflate",
 			expectCompressed: false,
 		},
 		{
 			name:             "No accept encoding header",
+			accept:           api.JsonMediaType,
 			acceptEncoding:   "",
 			expectCompressed: false,
 		},
+		{
+			name:             "SSZ",
+			accept:           api.OctetStreamMediaType,
+			acceptEncoding:   "gzip",
+			expectCompressed: false,
+		},
 	}
 
 	for _, tt := range tests {
 		t.Run(tt.name, func(t *testing.T) {
 			req := httptest.NewRequest("GET", "/", nil)
+			req.Header.Set("Accept", tt.accept)
 			if tt.acceptEncoding != "" {
 				req.Header.Set("Accept-Encoding", tt.acceptEncoding)
 			}

beacon-chain/blockchain/process_block_test.go

@@ -2796,7 +2796,7 @@ func TestProcessLightClientUpdate(t *testing.T) {
 			period := slots.SyncCommitteePeriod(slots.ToEpoch(l.AttestedState.Slot()))
 
 			// create and save old update
-			oldUpdate, err := lightClient.CreateDefaultLightClientUpdate(s.CurrentSlot(), l.AttestedState)
+			oldUpdate, err := lightClient.CreateDefaultLightClientUpdate(l.AttestedBlock)
 			require.NoError(t, err)
 
 			err = s.cfg.BeaconDB.SaveLightClientUpdate(ctx, period, oldUpdate)
@@ -2848,7 +2848,7 @@ func TestProcessLightClientUpdate(t *testing.T) {
 			period := slots.SyncCommitteePeriod(slots.ToEpoch(l.AttestedState.Slot()))
 
 			// create and save old update
-			oldUpdate, err := lightClient.CreateDefaultLightClientUpdate(s.CurrentSlot(), l.AttestedState)
+			oldUpdate, err := lightClient.CreateDefaultLightClientUpdate(l.AttestedBlock)
 			require.NoError(t, err)
 
 			scb := make([]byte, 64)
@@ -2954,7 +2954,7 @@ func TestProcessLightClientUpdate(t *testing.T) {
 			period := slots.SyncCommitteePeriod(slots.ToEpoch(l.AttestedState.Slot()))
 
 			// create and save old update
-			oldUpdate, err := lightClient.CreateDefaultLightClientUpdate(s.CurrentSlot(), l.AttestedState)
+			oldUpdate, err := lightClient.CreateDefaultLightClientUpdate(l.AttestedBlock)
 			require.NoError(t, err)
 
 			err = s.cfg.BeaconDB.SaveLightClientUpdate(ctx, period, oldUpdate)
@@ -3006,7 +3006,7 @@ func TestProcessLightClientUpdate(t *testing.T) {
 			period := slots.SyncCommitteePeriod(slots.ToEpoch(l.AttestedState.Slot()))
 
 			// create and save old update
-			oldUpdate, err := lightClient.CreateDefaultLightClientUpdate(s.CurrentSlot(), l.AttestedState)
+			oldUpdate, err := lightClient.CreateDefaultLightClientUpdate(l.AttestedBlock)
 			require.NoError(t, err)
 
 			scb := make([]byte, 64)
@@ -3112,7 +3112,7 @@ func TestProcessLightClientUpdate(t *testing.T) {
 			period := slots.SyncCommitteePeriod(slots.ToEpoch(l.AttestedState.Slot()))
 
 			// create and save old update
-			oldUpdate, err := lightClient.CreateDefaultLightClientUpdate(s.CurrentSlot(), l.AttestedState)
+			oldUpdate, err := lightClient.CreateDefaultLightClientUpdate(l.AttestedBlock)
 			require.NoError(t, err)
 
 			err = s.cfg.BeaconDB.SaveLightClientUpdate(ctx, period, oldUpdate)
@@ -3164,7 +3164,7 @@ func TestProcessLightClientUpdate(t *testing.T) {
 			period := slots.SyncCommitteePeriod(slots.ToEpoch(l.AttestedState.Slot()))
 
 			// create and save old update
-			oldUpdate, err := lightClient.CreateDefaultLightClientUpdate(s.CurrentSlot(), l.AttestedState)
+			oldUpdate, err := lightClient.CreateDefaultLightClientUpdate(l.AttestedBlock)
 			require.NoError(t, err)
 
 			scb := make([]byte, 64)
@@ -3647,7 +3647,7 @@ func TestProcessLightClientOptimisticUpdate(t *testing.T) {
 				expectedVersion = version.Altair
 			case 2:
 				forkEpoch = uint64(params.BeaconConfig().BellatrixForkEpoch)
-				expectedVersion = version.Altair
+				expectedVersion = version.Bellatrix
 			case 3:
 				forkEpoch = uint64(params.BeaconConfig().CapellaForkEpoch)
 				expectedVersion = version.Capella
@@ -3656,7 +3656,7 @@ func TestProcessLightClientOptimisticUpdate(t *testing.T) {
 				expectedVersion = version.Deneb
 			case 5:
 				forkEpoch = uint64(params.BeaconConfig().ElectraForkEpoch)
-				expectedVersion = version.Deneb
+				expectedVersion = version.Electra
 			default:
 				t.Errorf("Unsupported fork version %s", version.String(testVersion))
 			}
@@ -3801,7 +3801,7 @@ func TestProcessLightClientFinalityUpdate(t *testing.T) {
 				expectedVersion = version.Altair
 			case 2:
 				forkEpoch = uint64(params.BeaconConfig().BellatrixForkEpoch)
-				expectedVersion = version.Altair
+				expectedVersion = version.Bellatrix
 			case 3:
 				forkEpoch = uint64(params.BeaconConfig().CapellaForkEpoch)
 				expectedVersion = version.Capella

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

@@ -38,11 +38,14 @@ const (
 	// SingleAttReceived is sent after a single attestation object is received from gossip or rpc
 	SingleAttReceived = 9
 
+	// DataColumnSidecarReceived is sent after a data column sidecar is received from gossip or rpc.
+	DataColumnSidecarReceived = 10
+
 	// BlockGossipReceived is sent after a block has been received from gossip or API that passes validation rules.
-	BlockGossipReceived = 10
+	BlockGossipReceived = 11
 
 	// DataColumnReceived is sent after a data column has been seen after gossip validation rules.
-	DataColumnReceived = 11
+	DataColumnReceived = 12
 )
 
 // UnAggregatedAttReceivedData is the data sent with UnaggregatedAttReceived events.
@@ -94,6 +97,11 @@ type SingleAttReceivedData struct {
 	Attestation ethpb.Att
 }
 
+// DataColumnSidecarReceivedData is the data sent with DataColumnSidecarReceived events.
+type DataColumnSidecarReceivedData struct {
+	DataColumn *blocks.VerifiedRODataColumn
+}
+
 // BlockGossipReceivedData is the data sent with BlockGossipReceived events.
 type BlockGossipReceivedData struct {
 	// SignedBlock is the block that was received.

beacon-chain/core/helpers/beacon_committee.go

@@ -403,7 +403,7 @@ func AssignmentForValidator(
 			}
 		}
 	}
-	return nil // validator is not scheduled this epoch
+	return &LiteAssignment{} // validator is not scheduled this epoch
 }
 
 // CommitteeAssignments calculates committee assignments for each validator during the specified epoch.

beacon-chain/core/helpers/beacon_committee_test.go

@@ -912,6 +912,7 @@ func TestAssignmentForValidator(t *testing.T) {
 			{{4, 5, 6}},
 		}
 		got = helpers.AssignmentForValidator(bySlot, start, primitives.ValidatorIndex(99))
-		require.IsNil(t, got)
+		// should be empty to be safe
+		require.DeepEqual(t, &helpers.LiteAssignment{}, got)
 	})
 }

beacon-chain/core/light-client/BUILD.bazel

@@ -3,6 +3,7 @@ load("@prysm//tools/go:def.bzl", "go_library", "go_test")
 go_library(
     name = "go_default_library",
     srcs = [
+        "helpers.go",
         "lightclient.go",
         "store.go",
     ],
@@ -41,7 +42,6 @@ go_test(
         "//consensus-types:go_default_library",
         "//consensus-types/blocks:go_default_library",
         "//consensus-types/light-client:go_default_library",
-        "//consensus-types/primitives:go_default_library",
         "//encoding/ssz:go_default_library",
         "//proto/engine/v1:go_default_library",
         "//proto/prysm/v1alpha1:go_default_library",

beacon-chain/core/light-client/helpers.go

@@ -0,0 +1,243 @@
+package light_client
+
+import (
+	"context"
+	"fmt"
+
+	"github.com/OffchainLabs/prysm/v6/beacon-chain/execution"
+	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"
+	light_client "github.com/OffchainLabs/prysm/v6/consensus-types/light-client"
+	"github.com/OffchainLabs/prysm/v6/consensus-types/primitives"
+	enginev1 "github.com/OffchainLabs/prysm/v6/proto/engine/v1"
+	pb "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/protobuf/proto"
+)
+
+func createDefaultLightClientBootstrap(currentSlot primitives.Slot) (interfaces.LightClientBootstrap, error) {
+	currentEpoch := slots.ToEpoch(currentSlot)
+	syncCommitteeSize := params.BeaconConfig().SyncCommitteeSize
+	pubKeys := make([][]byte, syncCommitteeSize)
+	for i := uint64(0); i < syncCommitteeSize; i++ {
+		pubKeys[i] = make([]byte, fieldparams.BLSPubkeyLength)
+	}
+	currentSyncCommittee := &pb.SyncCommittee{
+		Pubkeys:         pubKeys,
+		AggregatePubkey: make([]byte, fieldparams.BLSPubkeyLength),
+	}
+
+	var currentSyncCommitteeBranch [][]byte
+	if currentEpoch >= params.BeaconConfig().ElectraForkEpoch {
+		currentSyncCommitteeBranch = make([][]byte, fieldparams.SyncCommitteeBranchDepthElectra)
+	} else {
+		currentSyncCommitteeBranch = make([][]byte, fieldparams.SyncCommitteeBranchDepth)
+	}
+	for i := 0; i < len(currentSyncCommitteeBranch); i++ {
+		currentSyncCommitteeBranch[i] = make([]byte, fieldparams.RootLength)
+	}
+
+	executionBranch := make([][]byte, fieldparams.ExecutionBranchDepth)
+	for i := 0; i < fieldparams.ExecutionBranchDepth; i++ {
+		executionBranch[i] = make([]byte, 32)
+	}
+
+	var m proto.Message
+	if currentEpoch < params.BeaconConfig().CapellaForkEpoch {
+		m = &pb.LightClientBootstrapAltair{
+			Header: &pb.LightClientHeaderAltair{
+				Beacon: &pb.BeaconBlockHeader{},
+			},
+			CurrentSyncCommittee:       currentSyncCommittee,
+			CurrentSyncCommitteeBranch: currentSyncCommitteeBranch,
+		}
+	} else if currentEpoch < params.BeaconConfig().DenebForkEpoch {
+		m = &pb.LightClientBootstrapCapella{
+			Header: &pb.LightClientHeaderCapella{
+				Beacon:          &pb.BeaconBlockHeader{},
+				Execution:       &enginev1.ExecutionPayloadHeaderCapella{},
+				ExecutionBranch: executionBranch,
+			},
+			CurrentSyncCommittee:       currentSyncCommittee,
+			CurrentSyncCommitteeBranch: currentSyncCommitteeBranch,
+		}
+	} else if currentEpoch < params.BeaconConfig().ElectraForkEpoch {
+		m = &pb.LightClientBootstrapDeneb{
+			Header: &pb.LightClientHeaderDeneb{
+				Beacon:          &pb.BeaconBlockHeader{},
+				Execution:       &enginev1.ExecutionPayloadHeaderDeneb{},
+				ExecutionBranch: executionBranch,
+			},
+			CurrentSyncCommittee:       currentSyncCommittee,
+			CurrentSyncCommitteeBranch: currentSyncCommitteeBranch,
+		}
+	} else {
+		m = &pb.LightClientBootstrapElectra{
+			Header: &pb.LightClientHeaderDeneb{
+				Beacon:          &pb.BeaconBlockHeader{},
+				Execution:       &enginev1.ExecutionPayloadHeaderDeneb{},
+				ExecutionBranch: executionBranch,
+			},
+			CurrentSyncCommittee:       currentSyncCommittee,
+			CurrentSyncCommitteeBranch: currentSyncCommitteeBranch,
+		}
+	}
+
+	return light_client.NewWrappedBootstrap(m)
+}
+
+func makeExecutionAndProofDeneb(ctx context.Context, blk interfaces.ReadOnlySignedBeaconBlock) (*enginev1.ExecutionPayloadHeaderDeneb, [][]byte, error) {
+	if blk.Version() < version.Capella {
+		p, err := execution.EmptyExecutionPayloadHeader(version.Deneb)
+		if err != nil {
+			return nil, nil, errors.Wrap(err, "could not get payload header")
+		}
+		payloadHeader, ok := p.(*enginev1.ExecutionPayloadHeaderDeneb)
+		if !ok {
+			return nil, nil, fmt.Errorf("payload header type %T is not %T", p, &enginev1.ExecutionPayloadHeaderDeneb{})
+		}
+		payloadProof := emptyPayloadProof()
+
+		return payloadHeader, payloadProof, nil
+	}
+
+	payload, err := blk.Block().Body().Execution()
+	if err != nil {
+		return nil, nil, errors.Wrap(err, "could not get execution payload")
+	}
+	transactionsRoot, err := ComputeTransactionsRoot(payload)
+	if err != nil {
+		return nil, nil, errors.Wrap(err, "could not get transactions root")
+	}
+	withdrawalsRoot, err := ComputeWithdrawalsRoot(payload)
+	if err != nil {
+		return nil, nil, errors.Wrap(err, "could not get withdrawals root")
+	}
+
+	payloadHeader := &enginev1.ExecutionPayloadHeaderDeneb{
+		ParentHash:       payload.ParentHash(),
+		FeeRecipient:     payload.FeeRecipient(),
+		StateRoot:        payload.StateRoot(),
+		ReceiptsRoot:     payload.ReceiptsRoot(),
+		LogsBloom:        payload.LogsBloom(),
+		PrevRandao:       payload.PrevRandao(),
+		BlockNumber:      payload.BlockNumber(),
+		GasLimit:         payload.GasLimit(),
+		GasUsed:          payload.GasUsed(),
+		Timestamp:        payload.Timestamp(),
+		ExtraData:        payload.ExtraData(),
+		BaseFeePerGas:    payload.BaseFeePerGas(),
+		BlockHash:        payload.BlockHash(),
+		TransactionsRoot: transactionsRoot,
+		WithdrawalsRoot:  withdrawalsRoot,
+		BlobGasUsed:      0,
+		ExcessBlobGas:    0,
+	}
+
+	if blk.Version() >= version.Deneb {
+		blobGasUsed, err := payload.BlobGasUsed()
+		if err != nil {
+			return nil, nil, errors.Wrap(err, "could not get blob gas used")
+		}
+		excessBlobGas, err := payload.ExcessBlobGas()
+		if err != nil {
+			return nil, nil, errors.Wrap(err, "could not get excess blob gas")
+		}
+
+		payloadHeader.BlobGasUsed = blobGasUsed
+		payloadHeader.ExcessBlobGas = excessBlobGas
+	}
+
+	payloadProof, err := blocks.PayloadProof(ctx, blk.Block())
+	if err != nil {
+		return nil, nil, errors.Wrap(err, "could not get execution payload proof")
+	}
+
+	return payloadHeader, payloadProof, nil
+}
+
+func makeExecutionAndProofCapella(ctx context.Context, blk interfaces.ReadOnlySignedBeaconBlock) (*enginev1.ExecutionPayloadHeaderCapella, [][]byte, error) {
+	if blk.Version() > version.Capella {
+		return nil, nil, fmt.Errorf("unsupported block version %s for capella execution payload", version.String(blk.Version()))
+	}
+	if blk.Version() < version.Capella {
+		p, err := execution.EmptyExecutionPayloadHeader(version.Capella)
+		if err != nil {
+			return nil, nil, errors.Wrap(err, "could not get payload header")
+		}
+		payloadHeader, ok := p.(*enginev1.ExecutionPayloadHeaderCapella)
+		if !ok {
+			return nil, nil, fmt.Errorf("payload header type %T is not %T", p, &enginev1.ExecutionPayloadHeaderCapella{})
+		}
+		payloadProof := emptyPayloadProof()
+
+		return payloadHeader, payloadProof, nil
+	}
+
+	payload, err := blk.Block().Body().Execution()
+	if err != nil {
+		return nil, nil, errors.Wrap(err, "could not get execution payload")
+	}
+	transactionsRoot, err := ComputeTransactionsRoot(payload)
+	if err != nil {
+		return nil, nil, errors.Wrap(err, "could not get transactions root")
+	}
+	withdrawalsRoot, err := ComputeWithdrawalsRoot(payload)
+	if err != nil {
+		return nil, nil, errors.Wrap(err, "could not get withdrawals root")
+	}
+
+	payloadHeader := &enginev1.ExecutionPayloadHeaderCapella{
+		ParentHash:       payload.ParentHash(),
+		FeeRecipient:     payload.FeeRecipient(),
+		StateRoot:        payload.StateRoot(),
+		ReceiptsRoot:     payload.ReceiptsRoot(),
+		LogsBloom:        payload.LogsBloom(),
+		PrevRandao:       payload.PrevRandao(),
+		BlockNumber:      payload.BlockNumber(),
+		GasLimit:         payload.GasLimit(),
+		GasUsed:          payload.GasUsed(),
+		Timestamp:        payload.Timestamp(),
+		ExtraData:        payload.ExtraData(),
+		BaseFeePerGas:    payload.BaseFeePerGas(),
+		BlockHash:        payload.BlockHash(),
+		TransactionsRoot: transactionsRoot,
+		WithdrawalsRoot:  withdrawalsRoot,
+	}
+
+	payloadProof, err := blocks.PayloadProof(ctx, blk.Block())
+	if err != nil {
+		return nil, nil, errors.Wrap(err, "could not get execution payload proof")
+	}
+
+	return payloadHeader, payloadProof, nil
+}
+
+func makeBeaconBlockHeader(blk interfaces.ReadOnlySignedBeaconBlock) (*pb.BeaconBlockHeader, error) {
+	parentRoot := blk.Block().ParentRoot()
+	stateRoot := blk.Block().StateRoot()
+	bodyRoot, err := blk.Block().Body().HashTreeRoot()
+	if err != nil {
+		return nil, errors.Wrap(err, "could not get body root")
+	}
+	return &pb.BeaconBlockHeader{
+		Slot:          blk.Block().Slot(),
+		ProposerIndex: blk.Block().ProposerIndex(),
+		ParentRoot:    parentRoot[:],
+		StateRoot:     stateRoot[:],
+		BodyRoot:      bodyRoot[:],
+	}, nil
+}
+
+func emptyPayloadProof() [][]byte {
+	branch := interfaces.LightClientExecutionBranch{}
+	proof := make([][]byte, len(branch))
+	for i, b := range branch {
+		proof[i] = b[:]
+	}
+	return proof
+}

beacon-chain/core/light-client/lightclient.go

@@ -6,12 +6,10 @@ import (
 	"fmt"
 	"reflect"
 
-	"github.com/OffchainLabs/prysm/v6/beacon-chain/execution"
 	"github.com/OffchainLabs/prysm/v6/beacon-chain/state"
 	fieldparams "github.com/OffchainLabs/prysm/v6/config/fieldparams"
 	"github.com/OffchainLabs/prysm/v6/config/params"
 	consensus_types "github.com/OffchainLabs/prysm/v6/consensus-types"
-	"github.com/OffchainLabs/prysm/v6/consensus-types/blocks"
 	"github.com/OffchainLabs/prysm/v6/consensus-types/interfaces"
 	light_client "github.com/OffchainLabs/prysm/v6/consensus-types/light-client"
 	"github.com/OffchainLabs/prysm/v6/consensus-types/primitives"
@@ -163,13 +161,13 @@ func NewLightClientUpdateFromBeaconState(
 	updateAttestedPeriod := slots.SyncCommitteePeriod(slots.ToEpoch(attestedBlock.Block().Slot()))
 
 	// update = LightClientUpdate()
-	result, err := CreateDefaultLightClientUpdate(currentSlot, attestedState)
+	result, err := CreateDefaultLightClientUpdate(attestedBlock)
 	if err != nil {
 		return nil, errors.Wrap(err, "could not create default light client update")
 	}
 
 	// update.attested_header = block_to_light_client_header(attested_block)
-	attestedLightClientHeader, err := BlockToLightClientHeader(ctx, currentSlot, attestedBlock)
+	attestedLightClientHeader, err := BlockToLightClientHeader(ctx, attestedBlock.Version(), attestedBlock)
 	if err != nil {
 		return nil, errors.Wrap(err, "could not get attested light client header")
 	}
@@ -210,7 +208,7 @@ func NewLightClientUpdateFromBeaconState(
 		// if finalized_block.message.slot != GENESIS_SLOT
 		if finalizedBlock.Block().Slot() != 0 {
 			// update.finalized_header = block_to_light_client_header(finalized_block)
-			finalizedLightClientHeader, err := BlockToLightClientHeader(ctx, currentSlot, finalizedBlock)
+			finalizedLightClientHeader, err := BlockToLightClientHeader(ctx, attestedBlock.Version(), finalizedBlock)
 			if err != nil {
 				return nil, errors.Wrap(err, "could not get finalized light client header")
 			}
@@ -247,9 +245,7 @@ func NewLightClientUpdateFromBeaconState(
 	return result, nil
 }
 
-func CreateDefaultLightClientUpdate(currentSlot primitives.Slot, attestedState state.BeaconState) (interfaces.LightClientUpdate, error) {
-	currentEpoch := slots.ToEpoch(currentSlot)
-
+func CreateDefaultLightClientUpdate(attestedBlock interfaces.ReadOnlySignedBeaconBlock) (interfaces.LightClientUpdate, error) {
 	syncCommitteeSize := params.BeaconConfig().SyncCommitteeSize
 	pubKeys := make([][]byte, syncCommitteeSize)
 	for i := uint64(0); i < syncCommitteeSize; i++ {
@@ -261,7 +257,7 @@ func CreateDefaultLightClientUpdate(currentSlot primitives.Slot, attestedState s
 	}
 
 	var nextSyncCommitteeBranch [][]byte
-	if attestedState.Version() >= version.Electra {
+	if attestedBlock.Version() >= version.Electra {
 		nextSyncCommitteeBranch = make([][]byte, fieldparams.SyncCommitteeBranchDepthElectra)
 	} else {
 		nextSyncCommitteeBranch = make([][]byte, fieldparams.SyncCommitteeBranchDepth)
@@ -276,7 +272,7 @@ func CreateDefaultLightClientUpdate(currentSlot primitives.Slot, attestedState s
 	}
 
 	var finalityBranch [][]byte
-	if attestedState.Version() >= version.Electra {
+	if attestedBlock.Version() >= version.Electra {
 		finalityBranch = make([][]byte, fieldparams.FinalityBranchDepthElectra)
 	} else {
 		finalityBranch = make([][]byte, fieldparams.FinalityBranchDepth)
@@ -286,10 +282,12 @@ func CreateDefaultLightClientUpdate(currentSlot primitives.Slot, attestedState s
 	}
 
 	var m proto.Message
-	if currentEpoch < params.BeaconConfig().CapellaForkEpoch {
+	switch attestedBlock.Version() {
+	case version.Altair, version.Bellatrix:
 		m = &pb.LightClientUpdateAltair{
 			AttestedHeader: &pb.LightClientHeaderAltair{
 				Beacon: &pb.BeaconBlockHeader{
+					Slot:       attestedBlock.Block().Slot(),
 					ParentRoot: make([]byte, 32),
 					StateRoot:  make([]byte, 32),
 					BodyRoot:   make([]byte, 32),
@@ -310,10 +308,11 @@ func CreateDefaultLightClientUpdate(currentSlot primitives.Slot, attestedState s
 				SyncCommitteeSignature: make([]byte, 96),
 			},
 		}
-	} else if currentEpoch < params.BeaconConfig().DenebForkEpoch {
+	case version.Capella:
 		m = &pb.LightClientUpdateCapella{
 			AttestedHeader: &pb.LightClientHeaderCapella{
 				Beacon: &pb.BeaconBlockHeader{
+					Slot:       attestedBlock.Block().Slot(),
 					ParentRoot: make([]byte, 32),
 					StateRoot:  make([]byte, 32),
 					BodyRoot:   make([]byte, 32),
@@ -362,10 +361,11 @@ func CreateDefaultLightClientUpdate(currentSlot primitives.Slot, attestedState s
 				SyncCommitteeSignature: make([]byte, 96),
 			},
 		}
-	} else if currentEpoch < params.BeaconConfig().ElectraForkEpoch {
+	case version.Deneb:
 		m = &pb.LightClientUpdateDeneb{
 			AttestedHeader: &pb.LightClientHeaderDeneb{
 				Beacon: &pb.BeaconBlockHeader{
+					Slot:       attestedBlock.Block().Slot(),
 					ParentRoot: make([]byte, 32),
 					StateRoot:  make([]byte, 32),
 					BodyRoot:   make([]byte, 32),
@@ -418,120 +418,65 @@ func CreateDefaultLightClientUpdate(currentSlot primitives.Slot, attestedState s
 				SyncCommitteeSignature: make([]byte, 96),
 			},
 		}
-	} else {
-		if attestedState.Version() >= version.Electra {
-			m = &pb.LightClientUpdateElectra{
-				AttestedHeader: &pb.LightClientHeaderDeneb{
-					Beacon: &pb.BeaconBlockHeader{
-						ParentRoot: make([]byte, 32),
-						StateRoot:  make([]byte, 32),
-						BodyRoot:   make([]byte, 32),
-					},
-					Execution: &enginev1.ExecutionPayloadHeaderDeneb{
-						ParentHash:       make([]byte, fieldparams.RootLength),
-						FeeRecipient:     make([]byte, fieldparams.FeeRecipientLength),
-						StateRoot:        make([]byte, fieldparams.RootLength),
-						ReceiptsRoot:     make([]byte, fieldparams.RootLength),
-						LogsBloom:        make([]byte, fieldparams.LogsBloomLength),
-						PrevRandao:       make([]byte, fieldparams.RootLength),
-						ExtraData:        make([]byte, 0),
-						BaseFeePerGas:    make([]byte, fieldparams.RootLength),
-						BlockHash:        make([]byte, fieldparams.RootLength),
-						TransactionsRoot: make([]byte, fieldparams.RootLength),
-						WithdrawalsRoot:  make([]byte, fieldparams.RootLength),
-						GasLimit:         0,
-						GasUsed:          0,
-					},
-					ExecutionBranch: executionBranch,
+	case version.Electra, version.Fulu:
+		m = &pb.LightClientUpdateElectra{
+			AttestedHeader: &pb.LightClientHeaderDeneb{
+				Beacon: &pb.BeaconBlockHeader{
+					Slot:       attestedBlock.Block().Slot(),
+					ParentRoot: make([]byte, 32),
+					StateRoot:  make([]byte, 32),
+					BodyRoot:   make([]byte, 32),
 				},
-				NextSyncCommittee:       nextSyncCommittee,
-				NextSyncCommitteeBranch: nextSyncCommitteeBranch,
-				FinalityBranch:          finalityBranch,
-				FinalizedHeader: &pb.LightClientHeaderDeneb{
-					Beacon: &pb.BeaconBlockHeader{
-						ParentRoot: make([]byte, 32),
-						StateRoot:  make([]byte, 32),
-						BodyRoot:   make([]byte, 32),
-					},
-					Execution: &enginev1.ExecutionPayloadHeaderDeneb{
-						ParentHash:       make([]byte, fieldparams.RootLength),
-						FeeRecipient:     make([]byte, fieldparams.FeeRecipientLength),
-						StateRoot:        make([]byte, fieldparams.RootLength),
-						ReceiptsRoot:     make([]byte, fieldparams.RootLength),
-						LogsBloom:        make([]byte, fieldparams.LogsBloomLength),
-						PrevRandao:       make([]byte, fieldparams.RootLength),
-						ExtraData:        make([]byte, 0),
-						BaseFeePerGas:    make([]byte, fieldparams.RootLength),
-						BlockHash:        make([]byte, fieldparams.RootLength),
-						TransactionsRoot: make([]byte, fieldparams.RootLength),
-						WithdrawalsRoot:  make([]byte, fieldparams.RootLength),
-						GasLimit:         0,
-						GasUsed:          0,
-					},
-					ExecutionBranch: executionBranch,
+				Execution: &enginev1.ExecutionPayloadHeaderDeneb{
+					ParentHash:       make([]byte, fieldparams.RootLength),
+					FeeRecipient:     make([]byte, fieldparams.FeeRecipientLength),
+					StateRoot:        make([]byte, fieldparams.RootLength),
+					ReceiptsRoot:     make([]byte, fieldparams.RootLength),
+					LogsBloom:        make([]byte, fieldparams.LogsBloomLength),
+					PrevRandao:       make([]byte, fieldparams.RootLength),
+					ExtraData:        make([]byte, 0),
+					BaseFeePerGas:    make([]byte, fieldparams.RootLength),
+					BlockHash:        make([]byte, fieldparams.RootLength),
+					TransactionsRoot: make([]byte, fieldparams.RootLength),
+					WithdrawalsRoot:  make([]byte, fieldparams.RootLength),
+					GasLimit:         0,
+					GasUsed:          0,
 				},
-				SyncAggregate: &pb.SyncAggregate{
-					SyncCommitteeBits:      make([]byte, 64),
-					SyncCommitteeSignature: make([]byte, 96),
+				ExecutionBranch: executionBranch,
+			},
+			NextSyncCommittee:       nextSyncCommittee,
+			NextSyncCommitteeBranch: nextSyncCommitteeBranch,
+			FinalityBranch:          finalityBranch,
+			FinalizedHeader: &pb.LightClientHeaderDeneb{
+				Beacon: &pb.BeaconBlockHeader{
+					ParentRoot: make([]byte, 32),
+					StateRoot:  make([]byte, 32),
+					BodyRoot:   make([]byte, 32),
 				},
-			}
-		} else {
-			m = &pb.LightClientUpdateDeneb{
-				AttestedHeader: &pb.LightClientHeaderDeneb{
-					Beacon: &pb.BeaconBlockHeader{
-						ParentRoot: make([]byte, 32),
-						StateRoot:  make([]byte, 32),
-						BodyRoot:   make([]byte, 32),
-					},
-					Execution: &enginev1.ExecutionPayloadHeaderDeneb{
-						ParentHash:       make([]byte, fieldparams.RootLength),
-						FeeRecipient:     make([]byte, fieldparams.FeeRecipientLength),
-						StateRoot:        make([]byte, fieldparams.RootLength),
-						ReceiptsRoot:     make([]byte, fieldparams.RootLength),
-						LogsBloom:        make([]byte, fieldparams.LogsBloomLength),
-						PrevRandao:       make([]byte, fieldparams.RootLength),
-						ExtraData:        make([]byte, 0),
-						BaseFeePerGas:    make([]byte, fieldparams.RootLength),
-						BlockHash:        make([]byte, fieldparams.RootLength),
-						TransactionsRoot: make([]byte, fieldparams.RootLength),
-						WithdrawalsRoot:  make([]byte, fieldparams.RootLength),
-						GasLimit:         0,
-						GasUsed:          0,
-					},
-					ExecutionBranch: executionBranch,
+				Execution: &enginev1.ExecutionPayloadHeaderDeneb{
+					ParentHash:       make([]byte, fieldparams.RootLength),
+					FeeRecipient:     make([]byte, fieldparams.FeeRecipientLength),
+					StateRoot:        make([]byte, fieldparams.RootLength),
+					ReceiptsRoot:     make([]byte, fieldparams.RootLength),
+					LogsBloom:        make([]byte, fieldparams.LogsBloomLength),
+					PrevRandao:       make([]byte, fieldparams.RootLength),
+					ExtraData:        make([]byte, 0),
+					BaseFeePerGas:    make([]byte, fieldparams.RootLength),
+					BlockHash:        make([]byte, fieldparams.RootLength),
+					TransactionsRoot: make([]byte, fieldparams.RootLength),
+					WithdrawalsRoot:  make([]byte, fieldparams.RootLength),
+					GasLimit:         0,
+					GasUsed:          0,
 				},
-				NextSyncCommittee:       nextSyncCommittee,
-				NextSyncCommitteeBranch: nextSyncCommitteeBranch,
-				FinalityBranch:          finalityBranch,
-				FinalizedHeader: &pb.LightClientHeaderDeneb{
-					Beacon: &pb.BeaconBlockHeader{
-						ParentRoot: make([]byte, 32),
-						StateRoot:  make([]byte, 32),
-						BodyRoot:   make([]byte, 32),
-					},
-					Execution: &enginev1.ExecutionPayloadHeaderDeneb{
-						ParentHash:       make([]byte, fieldparams.RootLength),
-						FeeRecipient:     make([]byte, fieldparams.FeeRecipientLength),
-						StateRoot:        make([]byte, fieldparams.RootLength),
-						ReceiptsRoot:     make([]byte, fieldparams.RootLength),
-						LogsBloom:        make([]byte, fieldparams.LogsBloomLength),
-						PrevRandao:       make([]byte, fieldparams.RootLength),
-						ExtraData:        make([]byte, 0),
-						BaseFeePerGas:    make([]byte, fieldparams.RootLength),
-						BlockHash:        make([]byte, fieldparams.RootLength),
-						TransactionsRoot: make([]byte, fieldparams.RootLength),
-						WithdrawalsRoot:  make([]byte, fieldparams.RootLength),
-						GasLimit:         0,
-						GasUsed:          0,
-					},
-					ExecutionBranch: executionBranch,
-				},
-				SyncAggregate: &pb.SyncAggregate{
-					SyncCommitteeBits:      make([]byte, 64),
-					SyncCommitteeSignature: make([]byte, 96),
-				},
-			}
+				ExecutionBranch: executionBranch,
+			},
+			SyncAggregate: &pb.SyncAggregate{
+				SyncCommitteeBits:      make([]byte, 64),
+				SyncCommitteeSignature: make([]byte, 96),
+			},
 		}
+	default:
+		return nil, errors.Errorf("unsupported beacon chain version %s", version.String(attestedBlock.Version()))
 	}
 
 	return light_client.NewWrappedUpdate(m)
@@ -575,189 +520,52 @@ func ComputeWithdrawalsRoot(payload interfaces.ExecutionData) ([]byte, error) {
 
 func BlockToLightClientHeader(
 	ctx context.Context,
-	currentSlot primitives.Slot,
-	block interfaces.ReadOnlySignedBeaconBlock,
+	attestedBlockVersion int, // this is the version that the light client header should be in, based on the attested block.
+	block interfaces.ReadOnlySignedBeaconBlock, // this block is either the attested block, or the finalized block.
+	// in case of the latter, we might need to upgrade it to the attested block's version.
 ) (interfaces.LightClientHeader, error) {
-	var m proto.Message
-	currentEpoch := slots.ToEpoch(currentSlot)
-	blockEpoch := slots.ToEpoch(block.Block().Slot())
-	parentRoot := block.Block().ParentRoot()
-	stateRoot := block.Block().StateRoot()
-	bodyRoot, err := block.Block().Body().HashTreeRoot()
-	if err != nil {
-		return nil, errors.Wrap(err, "could not get body root")
+	if block.Version() > attestedBlockVersion {
+		return nil, errors.Errorf("block version %s is greater than attested block version %s", version.String(block.Version()), version.String(attestedBlockVersion))
 	}
 
-	if currentEpoch < params.BeaconConfig().CapellaForkEpoch {
+	beacon, err := makeBeaconBlockHeader(block)
+	if err != nil {
+		return nil, errors.Wrap(err, "could not make beacon block header")
+	}
+
+	var m proto.Message
+	switch attestedBlockVersion {
+	case version.Altair, version.Bellatrix:
 		m = &pb.LightClientHeaderAltair{
-			Beacon: &pb.BeaconBlockHeader{
-				Slot:          block.Block().Slot(),
-				ProposerIndex: block.Block().ProposerIndex(),
-				ParentRoot:    parentRoot[:],
-				StateRoot:     stateRoot[:],
-				BodyRoot:      bodyRoot[:],
-			},
+			Beacon: beacon,
 		}
-	} else if currentEpoch < params.BeaconConfig().DenebForkEpoch {
-		var payloadHeader *enginev1.ExecutionPayloadHeaderCapella
-		var payloadProof [][]byte
-
-		if blockEpoch < params.BeaconConfig().CapellaForkEpoch {
-			var ok bool
-
-			p, err := execution.EmptyExecutionPayloadHeader(version.Capella)
-			if err != nil {
-				return nil, errors.Wrap(err, "could not get payload header")
-			}
-			payloadHeader, ok = p.(*enginev1.ExecutionPayloadHeaderCapella)
-			if !ok {
-				return nil, fmt.Errorf("payload header type %T is not %T", p, &enginev1.ExecutionPayloadHeaderCapella{})
-			}
-			payloadProof = emptyPayloadProof()
-		} else {
-			payload, err := block.Block().Body().Execution()
-			if err != nil {
-				return nil, errors.Wrap(err, "could not get execution payload")
-			}
-			transactionsRoot, err := ComputeTransactionsRoot(payload)
-			if err != nil {
-				return nil, errors.Wrap(err, "could not get transactions root")
-			}
-			withdrawalsRoot, err := ComputeWithdrawalsRoot(payload)
-			if err != nil {
-				return nil, errors.Wrap(err, "could not get withdrawals root")
-			}
-
-			payloadHeader = &enginev1.ExecutionPayloadHeaderCapella{
-				ParentHash:       payload.ParentHash(),
-				FeeRecipient:     payload.FeeRecipient(),
-				StateRoot:        payload.StateRoot(),
-				ReceiptsRoot:     payload.ReceiptsRoot(),
-				LogsBloom:        payload.LogsBloom(),
-				PrevRandao:       payload.PrevRandao(),
-				BlockNumber:      payload.BlockNumber(),
-				GasLimit:         payload.GasLimit(),
-				GasUsed:          payload.GasUsed(),
-				Timestamp:        payload.Timestamp(),
-				ExtraData:        payload.ExtraData(),
-				BaseFeePerGas:    payload.BaseFeePerGas(),
-				BlockHash:        payload.BlockHash(),
-				TransactionsRoot: transactionsRoot,
-				WithdrawalsRoot:  withdrawalsRoot,
-			}
-
-			payloadProof, err = blocks.PayloadProof(ctx, block.Block())
-			if err != nil {
-				return nil, errors.Wrap(err, "could not get execution payload proof")
-			}
+	case version.Capella:
+		payloadHeader, payloadProof, err := makeExecutionAndProofCapella(ctx, block)
+		if err != nil {
+			return nil, errors.Wrap(err, "could not make execution payload header and proof")
 		}
-
 		m = &pb.LightClientHeaderCapella{
-			Beacon: &pb.BeaconBlockHeader{
-				Slot:          block.Block().Slot(),
-				ProposerIndex: block.Block().ProposerIndex(),
-				ParentRoot:    parentRoot[:],
-				StateRoot:     stateRoot[:],
-				BodyRoot:      bodyRoot[:],
-			},
+			Beacon:          beacon,
 			Execution:       payloadHeader,
 			ExecutionBranch: payloadProof,
 		}
-	} else {
-		var payloadHeader *enginev1.ExecutionPayloadHeaderDeneb
-		var payloadProof [][]byte
-
-		if blockEpoch < params.BeaconConfig().CapellaForkEpoch {
-			var ok bool
-
-			p, err := execution.EmptyExecutionPayloadHeader(version.Deneb)
-			if err != nil {
-				return nil, errors.Wrap(err, "could not get payload header")
-			}
-			payloadHeader, ok = p.(*enginev1.ExecutionPayloadHeaderDeneb)
-			if !ok {
-				return nil, fmt.Errorf("payload header type %T is not %T", p, &enginev1.ExecutionPayloadHeaderDeneb{})
-			}
-			payloadProof = emptyPayloadProof()
-		} else {
-			payload, err := block.Block().Body().Execution()
-			if err != nil {
-				return nil, errors.Wrap(err, "could not get execution payload")
-			}
-			transactionsRoot, err := ComputeTransactionsRoot(payload)
-			if err != nil {
-				return nil, errors.Wrap(err, "could not get transactions root")
-			}
-			withdrawalsRoot, err := ComputeWithdrawalsRoot(payload)
-			if err != nil {
-				return nil, errors.Wrap(err, "could not get withdrawals root")
-			}
-
-			var blobGasUsed uint64
-			var excessBlobGas uint64
-
-			if blockEpoch >= params.BeaconConfig().DenebForkEpoch {
-				blobGasUsed, err = payload.BlobGasUsed()
-				if err != nil {
-					return nil, errors.Wrap(err, "could not get blob gas used")
-				}
-				excessBlobGas, err = payload.ExcessBlobGas()
-				if err != nil {
-					return nil, errors.Wrap(err, "could not get excess blob gas")
-				}
-			}
-
-			payloadHeader = &enginev1.ExecutionPayloadHeaderDeneb{
-				ParentHash:       payload.ParentHash(),
-				FeeRecipient:     payload.FeeRecipient(),
-				StateRoot:        payload.StateRoot(),
-				ReceiptsRoot:     payload.ReceiptsRoot(),
-				LogsBloom:        payload.LogsBloom(),
-				PrevRandao:       payload.PrevRandao(),
-				BlockNumber:      payload.BlockNumber(),
-				GasLimit:         payload.GasLimit(),
-				GasUsed:          payload.GasUsed(),
-				Timestamp:        payload.Timestamp(),
-				ExtraData:        payload.ExtraData(),
-				BaseFeePerGas:    payload.BaseFeePerGas(),
-				BlockHash:        payload.BlockHash(),
-				TransactionsRoot: transactionsRoot,
-				WithdrawalsRoot:  withdrawalsRoot,
-				BlobGasUsed:      blobGasUsed,
-				ExcessBlobGas:    excessBlobGas,
-			}
-
-			payloadProof, err = blocks.PayloadProof(ctx, block.Block())
-			if err != nil {
-				return nil, errors.Wrap(err, "could not get execution payload proof")
-			}
+	case version.Deneb, version.Electra, version.Fulu:
+		payloadHeader, payloadProof, err := makeExecutionAndProofDeneb(ctx, block)
+		if err != nil {
+			return nil, errors.Wrap(err, "could not make execution payload header and proof")
 		}
-
 		m = &pb.LightClientHeaderDeneb{
-			Beacon: &pb.BeaconBlockHeader{
-				Slot:          block.Block().Slot(),
-				ProposerIndex: block.Block().ProposerIndex(),
-				ParentRoot:    parentRoot[:],
-				StateRoot:     stateRoot[:],
-				BodyRoot:      bodyRoot[:],
-			},
+			Beacon:          beacon,
 			Execution:       payloadHeader,
 			ExecutionBranch: payloadProof,
 		}
+	default:
+		return nil, fmt.Errorf("unsupported attested block version %s", version.String(attestedBlockVersion))
 	}
 
 	return light_client.NewWrappedHeader(m)
 }
 
-func emptyPayloadProof() [][]byte {
-	branch := interfaces.LightClientExecutionBranch{}
-	proof := make([][]byte, len(branch))
-	for i, b := range branch {
-		proof[i] = b[:]
-	}
-	return proof
-}
-
 func HasRelevantSyncCommittee(update interfaces.LightClientUpdate) (bool, error) {
 	if update.Version() >= version.Electra {
 		branch, err := update.NextSyncCommitteeBranchElectra()
@@ -909,7 +717,7 @@ func NewLightClientBootstrapFromBeaconState(
 		return nil, errors.Wrap(err, "could not create default light client bootstrap")
 	}
 
-	lightClientHeader, err := BlockToLightClientHeader(ctx, currentSlot, block)
+	lightClientHeader, err := BlockToLightClientHeader(ctx, state.Version(), block)
 	if err != nil {
 		return nil, errors.Wrap(err, "could not convert block to light client header")
 	}
@@ -942,78 +750,6 @@ func NewLightClientBootstrapFromBeaconState(
 	return bootstrap, nil
 }
 
-func createDefaultLightClientBootstrap(currentSlot primitives.Slot) (interfaces.LightClientBootstrap, error) {
-	currentEpoch := slots.ToEpoch(currentSlot)
-	syncCommitteeSize := params.BeaconConfig().SyncCommitteeSize
-	pubKeys := make([][]byte, syncCommitteeSize)
-	for i := uint64(0); i < syncCommitteeSize; i++ {
-		pubKeys[i] = make([]byte, fieldparams.BLSPubkeyLength)
-	}
-	currentSyncCommittee := &pb.SyncCommittee{
-		Pubkeys:         pubKeys,
-		AggregatePubkey: make([]byte, fieldparams.BLSPubkeyLength),
-	}
-
-	var currentSyncCommitteeBranch [][]byte
-	if currentEpoch >= params.BeaconConfig().ElectraForkEpoch {
-		currentSyncCommitteeBranch = make([][]byte, fieldparams.SyncCommitteeBranchDepthElectra)
-	} else {
-		currentSyncCommitteeBranch = make([][]byte, fieldparams.SyncCommitteeBranchDepth)
-	}
-	for i := 0; i < len(currentSyncCommitteeBranch); i++ {
-		currentSyncCommitteeBranch[i] = make([]byte, fieldparams.RootLength)
-	}
-
-	executionBranch := make([][]byte, fieldparams.ExecutionBranchDepth)
-	for i := 0; i < fieldparams.ExecutionBranchDepth; i++ {
-		executionBranch[i] = make([]byte, 32)
-	}
-
-	// TODO: can this be based on the current epoch?
-	var m proto.Message
-	if currentEpoch < params.BeaconConfig().CapellaForkEpoch {
-		m = &pb.LightClientBootstrapAltair{
-			Header: &pb.LightClientHeaderAltair{
-				Beacon: &pb.BeaconBlockHeader{},
-			},
-			CurrentSyncCommittee:       currentSyncCommittee,
-			CurrentSyncCommitteeBranch: currentSyncCommitteeBranch,
-		}
-	} else if currentEpoch < params.BeaconConfig().DenebForkEpoch {
-		m = &pb.LightClientBootstrapCapella{
-			Header: &pb.LightClientHeaderCapella{
-				Beacon:          &pb.BeaconBlockHeader{},
-				Execution:       &enginev1.ExecutionPayloadHeaderCapella{},
-				ExecutionBranch: executionBranch,
-			},
-			CurrentSyncCommittee:       currentSyncCommittee,
-			CurrentSyncCommitteeBranch: currentSyncCommitteeBranch,
-		}
-	} else if currentEpoch < params.BeaconConfig().ElectraForkEpoch {
-		m = &pb.LightClientBootstrapDeneb{
-			Header: &pb.LightClientHeaderDeneb{
-				Beacon:          &pb.BeaconBlockHeader{},
-				Execution:       &enginev1.ExecutionPayloadHeaderDeneb{},
-				ExecutionBranch: executionBranch,
-			},
-			CurrentSyncCommittee:       currentSyncCommittee,
-			CurrentSyncCommitteeBranch: currentSyncCommitteeBranch,
-		}
-	} else {
-		m = &pb.LightClientBootstrapElectra{
-			Header: &pb.LightClientHeaderDeneb{
-				Beacon:          &pb.BeaconBlockHeader{},
-				Execution:       &enginev1.ExecutionPayloadHeaderDeneb{},
-				ExecutionBranch: executionBranch,
-			},
-			CurrentSyncCommittee:       currentSyncCommittee,
-			CurrentSyncCommitteeBranch: currentSyncCommitteeBranch,
-		}
-	}
-
-	return light_client.NewWrappedBootstrap(m)
-}
-
 func UpdateHasSupermajority(syncAggregate *pb.SyncAggregate) bool {
 	maxActiveParticipants := syncAggregate.SyncCommitteeBits.Len()
 	numActiveParticipants := syncAggregate.SyncCommitteeBits.Count()

beacon-chain/core/light-client/lightclient_test.go

@@ -7,7 +7,6 @@ import (
 
 	"github.com/OffchainLabs/prysm/v6/config/params"
 	light_client "github.com/OffchainLabs/prysm/v6/consensus-types/light-client"
-	"github.com/OffchainLabs/prysm/v6/consensus-types/primitives"
 	"github.com/OffchainLabs/prysm/v6/runtime/version"
 
 	lightClient "github.com/OffchainLabs/prysm/v6/beacon-chain/core/light-client"
@@ -547,7 +546,7 @@ func TestLightClient_BlockToLightClientHeader(t *testing.T) {
 
 		header, err := lightClient.BlockToLightClientHeader(
 			l.Ctx,
-			primitives.Slot(params.BeaconConfig().AltairForkEpoch)*params.BeaconConfig().SlotsPerEpoch,
+			version.Altair,
 			l.Block,
 		)
 		require.NoError(t, err)
@@ -570,7 +569,7 @@ func TestLightClient_BlockToLightClientHeader(t *testing.T) {
 
 		header, err := lightClient.BlockToLightClientHeader(
 			l.Ctx,
-			primitives.Slot(params.BeaconConfig().BellatrixForkEpoch)*params.BeaconConfig().SlotsPerEpoch,
+			version.Bellatrix,
 			l.Block,
 		)
 		require.NoError(t, err)
@@ -594,7 +593,7 @@ func TestLightClient_BlockToLightClientHeader(t *testing.T) {
 
 			header, err := lightClient.BlockToLightClientHeader(
 				l.Ctx,
-				primitives.Slot(params.BeaconConfig().CapellaForkEpoch)*params.BeaconConfig().SlotsPerEpoch,
+				version.Capella,
 				l.Block,
 			)
 			require.NoError(t, err)
@@ -655,7 +654,7 @@ func TestLightClient_BlockToLightClientHeader(t *testing.T) {
 
 			header, err := lightClient.BlockToLightClientHeader(
 				l.Ctx,
-				primitives.Slot(params.BeaconConfig().CapellaForkEpoch)*params.BeaconConfig().SlotsPerEpoch,
+				version.Capella,
 				l.Block,
 			)
 			require.NoError(t, err)
@@ -718,7 +717,7 @@ func TestLightClient_BlockToLightClientHeader(t *testing.T) {
 
 			header, err := lightClient.BlockToLightClientHeader(
 				l.Ctx,
-				primitives.Slot(params.BeaconConfig().DenebForkEpoch)*params.BeaconConfig().SlotsPerEpoch,
+				version.Deneb,
 				l.Block,
 			)
 			require.NoError(t, err)
@@ -787,7 +786,7 @@ func TestLightClient_BlockToLightClientHeader(t *testing.T) {
 
 			header, err := lightClient.BlockToLightClientHeader(
 				l.Ctx,
-				primitives.Slot(params.BeaconConfig().DenebForkEpoch)*params.BeaconConfig().SlotsPerEpoch,
+				version.Deneb,
 				l.Block,
 			)
 			require.NoError(t, err)
@@ -856,7 +855,7 @@ func TestLightClient_BlockToLightClientHeader(t *testing.T) {
 		t.Run("Non-Blinded Beacon Block", func(t *testing.T) {
 			l := util.NewTestLightClient(t, version.Electra)
 
-			header, err := lightClient.BlockToLightClientHeader(l.Ctx, l.State.Slot(), l.Block)
+			header, err := lightClient.BlockToLightClientHeader(l.Ctx, version.Electra, l.Block)
 			require.NoError(t, err)
 			require.NotNil(t, header, "header is nil")
 
@@ -921,7 +920,7 @@ func TestLightClient_BlockToLightClientHeader(t *testing.T) {
 		t.Run("Blinded Beacon Block", func(t *testing.T) {
 			l := util.NewTestLightClient(t, version.Electra, util.WithBlinded())
 
-			header, err := lightClient.BlockToLightClientHeader(l.Ctx, l.State.Slot(), l.Block)
+			header, err := lightClient.BlockToLightClientHeader(l.Ctx, version.Electra, l.Block)
 			require.NoError(t, err)
 			require.NotNil(t, header, "header is nil")
 
@@ -989,7 +988,7 @@ func TestLightClient_BlockToLightClientHeader(t *testing.T) {
 
 		header, err := lightClient.BlockToLightClientHeader(
 			l.Ctx,
-			primitives.Slot(params.BeaconConfig().CapellaForkEpoch)*params.BeaconConfig().SlotsPerEpoch,
+			version.Capella,
 			l.Block)
 		require.NoError(t, err)
 		require.NotNil(t, header, "header is nil")
@@ -1011,7 +1010,7 @@ func TestLightClient_BlockToLightClientHeader(t *testing.T) {
 
 		header, err := lightClient.BlockToLightClientHeader(
 			l.Ctx,
-			primitives.Slot(params.BeaconConfig().DenebForkEpoch)*params.BeaconConfig().SlotsPerEpoch,
+			version.Deneb,
 			l.Block)
 		require.NoError(t, err)
 		require.NotNil(t, header, "header is nil")
@@ -1034,7 +1033,7 @@ func TestLightClient_BlockToLightClientHeader(t *testing.T) {
 
 			header, err := lightClient.BlockToLightClientHeader(
 				l.Ctx,
-				primitives.Slot(params.BeaconConfig().DenebForkEpoch)*params.BeaconConfig().SlotsPerEpoch,
+				version.Deneb,
 				l.Block)
 			require.NoError(t, err)
 			require.NotNil(t, header, "header is nil")
@@ -1094,7 +1093,7 @@ func TestLightClient_BlockToLightClientHeader(t *testing.T) {
 
 			header, err := lightClient.BlockToLightClientHeader(
 				l.Ctx,
-				primitives.Slot(params.BeaconConfig().DenebForkEpoch)*params.BeaconConfig().SlotsPerEpoch,
+				version.Deneb,
 				l.Block)
 			require.NoError(t, err)
 			require.NotNil(t, header, "header is nil")
@@ -1180,14 +1179,13 @@ func createNonEmptyFinalityBranch() [][]byte {
 }
 
 func TestIsBetterUpdate(t *testing.T) {
-	config := params.BeaconConfig()
-	st, err := util.NewBeaconStateAltair()
+	blk, err := blocks.NewSignedBeaconBlock(util.NewBeaconBlockAltair())
 	require.NoError(t, err)
 
 	t.Run("new has supermajority but old doesn't", func(t *testing.T) {
-		oldUpdate, err := lightClient.CreateDefaultLightClientUpdate(primitives.Slot(config.AltairForkEpoch*primitives.Epoch(config.SlotsPerEpoch)).Add(1), st)
+		oldUpdate, err := lightClient.CreateDefaultLightClientUpdate(blk)
 		require.NoError(t, err)
-		newUpdate, err := lightClient.CreateDefaultLightClientUpdate(primitives.Slot(config.AltairForkEpoch*primitives.Epoch(config.SlotsPerEpoch)).Add(2), st)
+		newUpdate, err := lightClient.CreateDefaultLightClientUpdate(blk)
 		require.NoError(t, err)
 
 		oldUpdate.SetSyncAggregate(&pb.SyncAggregate{
@@ -1203,9 +1201,9 @@ func TestIsBetterUpdate(t *testing.T) {
 	})
 
 	t.Run("old has supermajority but new doesn't", func(t *testing.T) {
-		oldUpdate, err := lightClient.CreateDefaultLightClientUpdate(primitives.Slot(config.AltairForkEpoch*primitives.Epoch(config.SlotsPerEpoch)).Add(1), st)
+		oldUpdate, err := lightClient.CreateDefaultLightClientUpdate(blk)
 		require.NoError(t, err)
-		newUpdate, err := lightClient.CreateDefaultLightClientUpdate(primitives.Slot(config.AltairForkEpoch*primitives.Epoch(config.SlotsPerEpoch)).Add(2), st)
+		newUpdate, err := lightClient.CreateDefaultLightClientUpdate(blk)
 		require.NoError(t, err)
 
 		oldUpdate.SetSyncAggregate(&pb.SyncAggregate{
@@ -1221,9 +1219,9 @@ func TestIsBetterUpdate(t *testing.T) {
 	})
 
 	t.Run("new doesn't have supermajority and newNumActiveParticipants is greater than oldNumActiveParticipants", func(t *testing.T) {
-		oldUpdate, err := lightClient.CreateDefaultLightClientUpdate(primitives.Slot(config.AltairForkEpoch*primitives.Epoch(config.SlotsPerEpoch)).Add(1), st)
+		oldUpdate, err := lightClient.CreateDefaultLightClientUpdate(blk)
 		require.NoError(t, err)
-		newUpdate, err := lightClient.CreateDefaultLightClientUpdate(primitives.Slot(config.AltairForkEpoch*primitives.Epoch(config.SlotsPerEpoch)).Add(2), st)
+		newUpdate, err := lightClient.CreateDefaultLightClientUpdate(blk)
 		require.NoError(t, err)
 
 		oldUpdate.SetSyncAggregate(&pb.SyncAggregate{
@@ -1239,9 +1237,9 @@ func TestIsBetterUpdate(t *testing.T) {
 	})
 
 	t.Run("new doesn't have supermajority and newNumActiveParticipants is lesser than oldNumActiveParticipants", func(t *testing.T) {
-		oldUpdate, err := lightClient.CreateDefaultLightClientUpdate(primitives.Slot(config.AltairForkEpoch*primitives.Epoch(config.SlotsPerEpoch)).Add(1), st)
+		oldUpdate, err := lightClient.CreateDefaultLightClientUpdate(blk)
 		require.NoError(t, err)
-		newUpdate, err := lightClient.CreateDefaultLightClientUpdate(primitives.Slot(config.AltairForkEpoch*primitives.Epoch(config.SlotsPerEpoch)).Add(2), st)
+		newUpdate, err := lightClient.CreateDefaultLightClientUpdate(blk)
 		require.NoError(t, err)
 
 		oldUpdate.SetSyncAggregate(&pb.SyncAggregate{
@@ -1257,9 +1255,9 @@ func TestIsBetterUpdate(t *testing.T) {
 	})
 
 	t.Run("new has relevant sync committee but old doesn't", func(t *testing.T) {
-		oldUpdate, err := lightClient.CreateDefaultLightClientUpdate(primitives.Slot(config.AltairForkEpoch*primitives.Epoch(config.SlotsPerEpoch)).Add(1), st)
+		oldUpdate, err := lightClient.CreateDefaultLightClientUpdate(blk)
 		require.NoError(t, err)
-		newUpdate, err := lightClient.CreateDefaultLightClientUpdate(primitives.Slot(config.AltairForkEpoch*primitives.Epoch(config.SlotsPerEpoch)).Add(2), st)
+		newUpdate, err := lightClient.CreateDefaultLightClientUpdate(blk)
 		require.NoError(t, err)
 
 		oldUpdate.SetSyncAggregate(&pb.SyncAggregate{
@@ -1296,9 +1294,9 @@ func TestIsBetterUpdate(t *testing.T) {
 	})
 
 	t.Run("old has relevant sync committee but new doesn't", func(t *testing.T) {
-		oldUpdate, err := lightClient.CreateDefaultLightClientUpdate(primitives.Slot(config.AltairForkEpoch*primitives.Epoch(config.SlotsPerEpoch)).Add(1), st)
+		oldUpdate, err := lightClient.CreateDefaultLightClientUpdate(blk)
 		require.NoError(t, err)
-		newUpdate, err := lightClient.CreateDefaultLightClientUpdate(primitives.Slot(config.AltairForkEpoch*primitives.Epoch(config.SlotsPerEpoch)).Add(2), st)
+		newUpdate, err := lightClient.CreateDefaultLightClientUpdate(blk)
 		require.NoError(t, err)
 
 		oldUpdate.SetSyncAggregate(&pb.SyncAggregate{
@@ -1335,9 +1333,9 @@ func TestIsBetterUpdate(t *testing.T) {
 	})
 
 	t.Run("new has finality but old doesn't", func(t *testing.T) {
-		oldUpdate, err := lightClient.CreateDefaultLightClientUpdate(primitives.Slot(config.AltairForkEpoch*primitives.Epoch(config.SlotsPerEpoch)).Add(1), st)
+		oldUpdate, err := lightClient.CreateDefaultLightClientUpdate(blk)
 		require.NoError(t, err)
-		newUpdate, err := lightClient.CreateDefaultLightClientUpdate(primitives.Slot(config.AltairForkEpoch*primitives.Epoch(config.SlotsPerEpoch)).Add(2), st)
+		newUpdate, err := lightClient.CreateDefaultLightClientUpdate(blk)
 		require.NoError(t, err)
 
 		oldUpdate.SetSyncAggregate(&pb.SyncAggregate{
@@ -1378,9 +1376,9 @@ func TestIsBetterUpdate(t *testing.T) {
 	})
 
 	t.Run("old has finality but new doesn't", func(t *testing.T) {
-		oldUpdate, err := lightClient.CreateDefaultLightClientUpdate(primitives.Slot(config.AltairForkEpoch*primitives.Epoch(config.SlotsPerEpoch)).Add(1), st)
+		oldUpdate, err := lightClient.CreateDefaultLightClientUpdate(blk)
 		require.NoError(t, err)
-		newUpdate, err := lightClient.CreateDefaultLightClientUpdate(primitives.Slot(config.AltairForkEpoch*primitives.Epoch(config.SlotsPerEpoch)).Add(2), st)
+		newUpdate, err := lightClient.CreateDefaultLightClientUpdate(blk)
 		require.NoError(t, err)
 
 		oldUpdate.SetSyncAggregate(&pb.SyncAggregate{
@@ -1421,9 +1419,9 @@ func TestIsBetterUpdate(t *testing.T) {
 	})
 
 	t.Run("new has finality and sync committee finality both but old doesn't have sync committee finality", func(t *testing.T) {
-		oldUpdate, err := lightClient.CreateDefaultLightClientUpdate(primitives.Slot(config.AltairForkEpoch*primitives.Epoch(config.SlotsPerEpoch)).Add(1), st)
+		oldUpdate, err := lightClient.CreateDefaultLightClientUpdate(blk)
 		require.NoError(t, err)
-		newUpdate, err := lightClient.CreateDefaultLightClientUpdate(primitives.Slot(config.AltairForkEpoch*primitives.Epoch(config.SlotsPerEpoch)).Add(2), st)
+		newUpdate, err := lightClient.CreateDefaultLightClientUpdate(blk)
 		require.NoError(t, err)
 
 		oldUpdate.SetSyncAggregate(&pb.SyncAggregate{
@@ -1482,9 +1480,9 @@ func TestIsBetterUpdate(t *testing.T) {
 	})
 
 	t.Run("new has finality but doesn't have sync committee finality and old has sync committee finality", func(t *testing.T) {
-		oldUpdate, err := lightClient.CreateDefaultLightClientUpdate(primitives.Slot(config.AltairForkEpoch*primitives.Epoch(config.SlotsPerEpoch)).Add(1), st)
+		oldUpdate, err := lightClient.CreateDefaultLightClientUpdate(blk)
 		require.NoError(t, err)
-		newUpdate, err := lightClient.CreateDefaultLightClientUpdate(primitives.Slot(config.AltairForkEpoch*primitives.Epoch(config.SlotsPerEpoch)).Add(2), st)
+		newUpdate, err := lightClient.CreateDefaultLightClientUpdate(blk)
 		require.NoError(t, err)
 
 		oldUpdate.SetSyncAggregate(&pb.SyncAggregate{
@@ -1543,9 +1541,9 @@ func TestIsBetterUpdate(t *testing.T) {
 	})
 
 	t.Run("new has more active participants than old", func(t *testing.T) {
-		oldUpdate, err := lightClient.CreateDefaultLightClientUpdate(primitives.Slot(config.AltairForkEpoch*primitives.Epoch(config.SlotsPerEpoch)).Add(1), st)
+		oldUpdate, err := lightClient.CreateDefaultLightClientUpdate(blk)
 		require.NoError(t, err)
-		newUpdate, err := lightClient.CreateDefaultLightClientUpdate(primitives.Slot(config.AltairForkEpoch*primitives.Epoch(config.SlotsPerEpoch)).Add(2), st)
+		newUpdate, err := lightClient.CreateDefaultLightClientUpdate(blk)
 		require.NoError(t, err)
 
 		oldUpdate.SetSyncAggregate(&pb.SyncAggregate{
@@ -1561,9 +1559,9 @@ func TestIsBetterUpdate(t *testing.T) {
 	})
 
 	t.Run("new has less active participants than old", func(t *testing.T) {
-		oldUpdate, err := lightClient.CreateDefaultLightClientUpdate(primitives.Slot(config.AltairForkEpoch*primitives.Epoch(config.SlotsPerEpoch)).Add(1), st)
+		oldUpdate, err := lightClient.CreateDefaultLightClientUpdate(blk)
 		require.NoError(t, err)
-		newUpdate, err := lightClient.CreateDefaultLightClientUpdate(primitives.Slot(config.AltairForkEpoch*primitives.Epoch(config.SlotsPerEpoch)).Add(2), st)
+		newUpdate, err := lightClient.CreateDefaultLightClientUpdate(blk)
 		require.NoError(t, err)
 
 		oldUpdate.SetSyncAggregate(&pb.SyncAggregate{
@@ -1579,9 +1577,9 @@ func TestIsBetterUpdate(t *testing.T) {
 	})
 
 	t.Run("new's attested header's slot is lesser than old's attested header's slot", func(t *testing.T) {
-		oldUpdate, err := lightClient.CreateDefaultLightClientUpdate(primitives.Slot(config.AltairForkEpoch*primitives.Epoch(config.SlotsPerEpoch)).Add(1), st)
+		oldUpdate, err := lightClient.CreateDefaultLightClientUpdate(blk)
 		require.NoError(t, err)
-		newUpdate, err := lightClient.CreateDefaultLightClientUpdate(primitives.Slot(config.AltairForkEpoch*primitives.Epoch(config.SlotsPerEpoch)).Add(2), st)
+		newUpdate, err := lightClient.CreateDefaultLightClientUpdate(blk)
 		require.NoError(t, err)
 
 		oldUpdate.SetSyncAggregate(&pb.SyncAggregate{
@@ -1640,9 +1638,9 @@ func TestIsBetterUpdate(t *testing.T) {
 	})
 
 	t.Run("new's attested header's slot is greater than old's attested header's slot", func(t *testing.T) {
-		oldUpdate, err := lightClient.CreateDefaultLightClientUpdate(primitives.Slot(config.AltairForkEpoch*primitives.Epoch(config.SlotsPerEpoch)).Add(1), st)
+		oldUpdate, err := lightClient.CreateDefaultLightClientUpdate(blk)
 		require.NoError(t, err)
-		newUpdate, err := lightClient.CreateDefaultLightClientUpdate(primitives.Slot(config.AltairForkEpoch*primitives.Epoch(config.SlotsPerEpoch)).Add(2), st)
+		newUpdate, err := lightClient.CreateDefaultLightClientUpdate(blk)
 		require.NoError(t, err)
 
 		oldUpdate.SetSyncAggregate(&pb.SyncAggregate{
@@ -1701,9 +1699,9 @@ func TestIsBetterUpdate(t *testing.T) {
 	})
 
 	t.Run("none of the above conditions are met and new signature's slot is less than old signature's slot", func(t *testing.T) {
-		oldUpdate, err := lightClient.CreateDefaultLightClientUpdate(primitives.Slot(config.AltairForkEpoch*primitives.Epoch(config.SlotsPerEpoch)).Add(1), st)
+		oldUpdate, err := lightClient.CreateDefaultLightClientUpdate(blk)
 		require.NoError(t, err)
-		newUpdate, err := lightClient.CreateDefaultLightClientUpdate(primitives.Slot(config.AltairForkEpoch*primitives.Epoch(config.SlotsPerEpoch)).Add(2), st)
+		newUpdate, err := lightClient.CreateDefaultLightClientUpdate(blk)
 		require.NoError(t, err)
 
 		oldUpdate.SetSyncAggregate(&pb.SyncAggregate{
@@ -1762,9 +1760,9 @@ func TestIsBetterUpdate(t *testing.T) {
 	})
 
 	t.Run("none of the above conditions are met and new signature's slot is greater than old signature's slot", func(t *testing.T) {
-		oldUpdate, err := lightClient.CreateDefaultLightClientUpdate(primitives.Slot(config.AltairForkEpoch*primitives.Epoch(config.SlotsPerEpoch)).Add(1), st)
+		oldUpdate, err := lightClient.CreateDefaultLightClientUpdate(blk)
 		require.NoError(t, err)
-		newUpdate, err := lightClient.CreateDefaultLightClientUpdate(primitives.Slot(config.AltairForkEpoch*primitives.Epoch(config.SlotsPerEpoch)).Add(2), st)
+		newUpdate, err := lightClient.CreateDefaultLightClientUpdate(blk)
 		require.NoError(t, err)
 
 		oldUpdate.SetSyncAggregate(&pb.SyncAggregate{

beacon-chain/core/light-client/store.go

@@ -13,6 +13,10 @@ type Store struct {
 	lastOptimisticUpdate interfaces.LightClientOptimisticUpdate
 }
 
+func NewLightClientStore() *Store {
+	return &Store{}
+}
+
 func (s *Store) SetLastFinalityUpdate(update interfaces.LightClientFinalityUpdate) {
 	s.mu.Lock()
 	defer s.mu.Unlock()

beacon-chain/db/kv/lightclient.go

@@ -153,6 +153,13 @@ func decodeLightClientBootstrap(enc []byte) (interfaces.LightClientBootstrap, []
 		}
 		m = bootstrap
 		syncCommitteeHash = enc[len(altairKey) : len(altairKey)+32]
+	case hasBellatrixKey(enc):
+		bootstrap := &ethpb.LightClientBootstrapAltair{}
+		if err := bootstrap.UnmarshalSSZ(enc[len(bellatrixKey)+32:]); err != nil {
+			return nil, nil, errors.Wrap(err, "could not unmarshal Bellatrix light client bootstrap")
+		}
+		m = bootstrap
+		syncCommitteeHash = enc[len(bellatrixKey) : len(bellatrixKey)+32]
 	case hasCapellaKey(enc):
 		bootstrap := &ethpb.LightClientBootstrapCapella{}
 		if err := bootstrap.UnmarshalSSZ(enc[len(capellaKey)+32:]); err != nil {
@@ -265,6 +272,12 @@ func decodeLightClientUpdate(enc []byte) (interfaces.LightClientUpdate, error) {
 			return nil, errors.Wrap(err, "could not unmarshal Altair light client update")
 		}
 		m = update
+	case hasBellatrixKey(enc):
+		update := &ethpb.LightClientUpdateAltair{}
+		if err := update.UnmarshalSSZ(enc[len(bellatrixKey):]); err != nil {
+			return nil, errors.Wrap(err, "could not unmarshal Bellatrix light client update")
+		}
+		m = update
 	case hasCapellaKey(enc):
 		update := &ethpb.LightClientUpdateCapella{}
 		if err := update.UnmarshalSSZ(enc[len(capellaKey):]); err != nil {
@@ -297,6 +310,8 @@ func keyForLightClientUpdate(v int) ([]byte, error) {
 		return denebKey, nil
 	case version.Capella:
 		return capellaKey, nil
+	case version.Bellatrix:
+		return bellatrixKey, nil
 	case version.Altair:
 		return altairKey, nil
 	default:

beacon-chain/db/kv/lightclient_test.go

@@ -46,7 +46,21 @@ func createUpdate(t *testing.T, v int) (interfaces.LightClientUpdate, error) {
 		slot = primitives.Slot(config.AltairForkEpoch * primitives.Epoch(config.SlotsPerEpoch)).Add(1)
 		header, err = light_client.NewWrappedHeader(&pb.LightClientHeaderAltair{
 			Beacon: &pb.BeaconBlockHeader{
-				Slot:          1,
+				Slot:          slot,
+				ProposerIndex: primitives.ValidatorIndex(rand.Int()),
+				ParentRoot:    sampleRoot,
+				StateRoot:     sampleRoot,
+				BodyRoot:      sampleRoot,
+			},
+		})
+		require.NoError(t, err)
+		st, err = util.NewBeaconState()
+		require.NoError(t, err)
+	case version.Bellatrix:
+		slot = primitives.Slot(config.BellatrixForkEpoch * primitives.Epoch(config.SlotsPerEpoch)).Add(1)
+		header, err = light_client.NewWrappedHeader(&pb.LightClientHeaderAltair{
+			Beacon: &pb.BeaconBlockHeader{
+				Slot:          slot,
 				ProposerIndex: primitives.ValidatorIndex(rand.Int()),
 				ParentRoot:    sampleRoot,
 				StateRoot:     sampleRoot,
@@ -60,7 +74,7 @@ func createUpdate(t *testing.T, v int) (interfaces.LightClientUpdate, error) {
 		slot = primitives.Slot(config.CapellaForkEpoch * primitives.Epoch(config.SlotsPerEpoch)).Add(1)
 		header, err = light_client.NewWrappedHeader(&pb.LightClientHeaderCapella{
 			Beacon: &pb.BeaconBlockHeader{
-				Slot:          1,
+				Slot:          slot,
 				ProposerIndex: primitives.ValidatorIndex(rand.Int()),
 				ParentRoot:    sampleRoot,
 				StateRoot:     sampleRoot,
@@ -88,7 +102,7 @@ func createUpdate(t *testing.T, v int) (interfaces.LightClientUpdate, error) {
 		slot = primitives.Slot(config.DenebForkEpoch * primitives.Epoch(config.SlotsPerEpoch)).Add(1)
 		header, err = light_client.NewWrappedHeader(&pb.LightClientHeaderDeneb{
 			Beacon: &pb.BeaconBlockHeader{
-				Slot:          1,
+				Slot:          slot,
 				ProposerIndex: primitives.ValidatorIndex(rand.Int()),
 				ParentRoot:    sampleRoot,
 				StateRoot:     sampleRoot,
@@ -116,7 +130,7 @@ func createUpdate(t *testing.T, v int) (interfaces.LightClientUpdate, error) {
 		slot = primitives.Slot(config.ElectraForkEpoch * primitives.Epoch(config.SlotsPerEpoch)).Add(1)
 		header, err = light_client.NewWrappedHeader(&pb.LightClientHeaderDeneb{
 			Beacon: &pb.BeaconBlockHeader{
-				Slot:          1,
+				Slot:          slot,
 				ProposerIndex: primitives.ValidatorIndex(rand.Int()),
 				ParentRoot:    sampleRoot,
 				StateRoot:     sampleRoot,
@@ -144,7 +158,7 @@ func createUpdate(t *testing.T, v int) (interfaces.LightClientUpdate, error) {
 		slot = primitives.Slot(config.FuluForkEpoch * primitives.Epoch(config.SlotsPerEpoch)).Add(1)
 		header, err = light_client.NewWrappedHeader(&pb.LightClientHeaderDeneb{
 			Beacon: &pb.BeaconBlockHeader{
-				Slot:          1,
+				Slot:          slot,
 				ProposerIndex: primitives.ValidatorIndex(rand.Int()),
 				ParentRoot:    sampleRoot,
 				StateRoot:     sampleRoot,
@@ -192,71 +206,30 @@ func TestStore_LightClientUpdate_CanSaveRetrieve(t *testing.T) {
 	params.SetupTestConfigCleanup(t)
 	cfg := params.BeaconConfig()
 	cfg.AltairForkEpoch = 0
-	cfg.CapellaForkEpoch = 1
-	cfg.DenebForkEpoch = 2
-	cfg.ElectraForkEpoch = 3
-	cfg.FuluForkEpoch = 3
+	cfg.BellatrixForkEpoch = 1
+	cfg.CapellaForkEpoch = 2
+	cfg.DenebForkEpoch = 3
+	cfg.ElectraForkEpoch = 4
+	cfg.FuluForkEpoch = 5
 	params.OverrideBeaconConfig(cfg)
 
 	db := setupDB(t)
 	ctx := t.Context()
 
-	t.Run("Altair", func(t *testing.T) {
-		update, err := createUpdate(t, version.Altair)
-		require.NoError(t, err)
-		period := uint64(1)
+	for testVersion := version.Altair; testVersion <= version.Electra; testVersion++ {
+		t.Run(version.String(testVersion), func(t *testing.T) {
+			update, err := createUpdate(t, testVersion)
+			require.NoError(t, err)
+			period := uint64(1)
 
-		err = db.SaveLightClientUpdate(ctx, period, update)
-		require.NoError(t, err)
+			err = db.SaveLightClientUpdate(ctx, period, update)
+			require.NoError(t, err)
 
-		retrievedUpdate, err := db.LightClientUpdate(ctx, period)
-		require.NoError(t, err)
-		require.DeepEqual(t, update, retrievedUpdate, "retrieved update does not match saved update")
-	})
-	t.Run("Capella", func(t *testing.T) {
-		update, err := createUpdate(t, version.Capella)
-		require.NoError(t, err)
-		period := uint64(1)
-		err = db.SaveLightClientUpdate(ctx, period, update)
-		require.NoError(t, err)
-
-		retrievedUpdate, err := db.LightClientUpdate(ctx, period)
-		require.NoError(t, err)
-		require.DeepEqual(t, update, retrievedUpdate, "retrieved update does not match saved update")
-	})
-	t.Run("Deneb", func(t *testing.T) {
-		update, err := createUpdate(t, version.Deneb)
-		require.NoError(t, err)
-		period := uint64(1)
-		err = db.SaveLightClientUpdate(ctx, period, update)
-		require.NoError(t, err)
-
-		retrievedUpdate, err := db.LightClientUpdate(ctx, period)
-		require.NoError(t, err)
-		require.DeepEqual(t, update, retrievedUpdate, "retrieved update does not match saved update")
-	})
-	t.Run("Electra", func(t *testing.T) {
-		update, err := createUpdate(t, version.Electra)
-		require.NoError(t, err)
-		period := uint64(1)
-		err = db.SaveLightClientUpdate(ctx, period, update)
-		require.NoError(t, err)
-
-		retrievedUpdate, err := db.LightClientUpdate(ctx, period)
-		require.NoError(t, err)
-		require.DeepEqual(t, update, retrievedUpdate, "retrieved update does not match saved update")
-	})
-	t.Run("Fulu", func(t *testing.T) {
-		update, err := createUpdate(t, version.Fulu)
-		require.NoError(t, err)
-		period := uint64(1)
-		err = db.SaveLightClientUpdate(ctx, period, update)
-		require.NoError(t, err)
-
-		retrievedUpdate, err := db.LightClientUpdate(ctx, period)
-		require.NoError(t, err)
-		require.DeepEqual(t, update, retrievedUpdate, "retrieved update does not match saved update")
-	})
+			retrievedUpdate, err := db.LightClientUpdate(ctx, period)
+			require.NoError(t, err)
+			require.DeepEqual(t, update, retrievedUpdate, "retrieved update does not match saved update")
+		})
+	}
 }
 
 func TestStore_LightClientUpdates_canRetrieveRange(t *testing.T) {
@@ -584,12 +557,21 @@ func TestStore_LightClientBootstrap_CanSaveRetrieve(t *testing.T) {
 	params.SetupTestConfigCleanup(t)
 	cfg := params.BeaconConfig()
 	cfg.AltairForkEpoch = 0
-	cfg.CapellaForkEpoch = 1
-	cfg.DenebForkEpoch = 2
-	cfg.ElectraForkEpoch = 3
+	cfg.BellatrixForkEpoch = 1
+	cfg.CapellaForkEpoch = 2
+	cfg.DenebForkEpoch = 3
+	cfg.ElectraForkEpoch = 4
 	cfg.EpochsPerSyncCommitteePeriod = 1
 	params.OverrideBeaconConfig(cfg)
 
+	versionToForkEpoch := map[int]primitives.Epoch{
+		version.Altair:    params.BeaconConfig().AltairForkEpoch,
+		version.Bellatrix: params.BeaconConfig().BellatrixForkEpoch,
+		version.Capella:   params.BeaconConfig().CapellaForkEpoch,
+		version.Deneb:     params.BeaconConfig().DenebForkEpoch,
+		version.Electra:   params.BeaconConfig().ElectraForkEpoch,
+	}
+
 	db := setupDB(t)
 	ctx := t.Context()
 
@@ -599,89 +581,38 @@ func TestStore_LightClientBootstrap_CanSaveRetrieve(t *testing.T) {
 		require.IsNil(t, retrievedBootstrap)
 	})
 
-	t.Run("Altair", func(t *testing.T) {
-		bootstrap, err := createDefaultLightClientBootstrap(primitives.Slot(uint64(params.BeaconConfig().AltairForkEpoch) * uint64(params.BeaconConfig().SlotsPerEpoch)))
-		require.NoError(t, err)
+	for testVersion := version.Altair; testVersion <= version.Electra; testVersion++ {
+		t.Run(version.String(testVersion), func(t *testing.T) {
+			bootstrap, err := createDefaultLightClientBootstrap(primitives.Slot(uint64(versionToForkEpoch[testVersion]) * uint64(params.BeaconConfig().SlotsPerEpoch)))
+			require.NoError(t, err)
 
-		err = bootstrap.SetCurrentSyncCommittee(createRandomSyncCommittee())
-		require.NoError(t, err)
+			err = bootstrap.SetCurrentSyncCommittee(createRandomSyncCommittee())
+			require.NoError(t, err)
 
-		err = db.SaveLightClientBootstrap(ctx, []byte("blockRootAltair"), bootstrap)
-		require.NoError(t, err)
+			blockRoot := []byte("blockRootAltair" + version.String(testVersion))
 
-		retrievedBootstrap, err := db.LightClientBootstrap(ctx, []byte("blockRootAltair"))
-		require.NoError(t, err)
-		require.DeepEqual(t, bootstrap.Header(), retrievedBootstrap.Header(), "retrieved bootstrap header does not match saved bootstrap header")
-		require.DeepEqual(t, bootstrap.CurrentSyncCommittee(), retrievedBootstrap.CurrentSyncCommittee(), "retrieved bootstrap sync committee does not match saved bootstrap sync committee")
-		savedBranch, err := bootstrap.CurrentSyncCommitteeBranch()
-		require.NoError(t, err)
-		retrievedBranch, err := retrievedBootstrap.CurrentSyncCommitteeBranch()
-		require.NoError(t, err)
-		require.DeepEqual(t, savedBranch, retrievedBranch, "retrieved bootstrap sync committee branch does not match saved bootstrap sync committee branch")
-	})
+			err = db.SaveLightClientBootstrap(ctx, blockRoot, bootstrap)
+			require.NoError(t, err)
 
-	t.Run("Capella", func(t *testing.T) {
-		bootstrap, err := createDefaultLightClientBootstrap(primitives.Slot(uint64(params.BeaconConfig().CapellaForkEpoch) * uint64(params.BeaconConfig().SlotsPerEpoch)))
-		require.NoError(t, err)
-
-		err = bootstrap.SetCurrentSyncCommittee(createRandomSyncCommittee())
-		require.NoError(t, err)
-
-		err = db.SaveLightClientBootstrap(ctx, []byte("blockRootCapella"), bootstrap)
-		require.NoError(t, err)
-
-		retrievedBootstrap, err := db.LightClientBootstrap(ctx, []byte("blockRootCapella"))
-		require.NoError(t, err)
-		require.DeepEqual(t, bootstrap.Header(), retrievedBootstrap.Header(), "retrieved bootstrap header does not match saved bootstrap header")
-		require.DeepEqual(t, bootstrap.CurrentSyncCommittee(), retrievedBootstrap.CurrentSyncCommittee(), "retrieved bootstrap sync committee does not match saved bootstrap sync committee")
-		savedBranch, err := bootstrap.CurrentSyncCommitteeBranch()
-		require.NoError(t, err)
-		retrievedBranch, err := retrievedBootstrap.CurrentSyncCommitteeBranch()
-		require.NoError(t, err)
-		require.DeepEqual(t, savedBranch, retrievedBranch, "retrieved bootstrap sync committee branch does not match saved bootstrap sync committee branch")
-	})
-
-	t.Run("Deneb", func(t *testing.T) {
-		bootstrap, err := createDefaultLightClientBootstrap(primitives.Slot(uint64(params.BeaconConfig().DenebForkEpoch) * uint64(params.BeaconConfig().SlotsPerEpoch)))
-		require.NoError(t, err)
-
-		err = bootstrap.SetCurrentSyncCommittee(createRandomSyncCommittee())
-		require.NoError(t, err)
-
-		err = db.SaveLightClientBootstrap(ctx, []byte("blockRootDeneb"), bootstrap)
-		require.NoError(t, err)
-
-		retrievedBootstrap, err := db.LightClientBootstrap(ctx, []byte("blockRootDeneb"))
-		require.NoError(t, err)
-		require.DeepEqual(t, bootstrap.Header(), retrievedBootstrap.Header(), "retrieved bootstrap header does not match saved bootstrap header")
-		require.DeepEqual(t, bootstrap.CurrentSyncCommittee(), retrievedBootstrap.CurrentSyncCommittee(), "retrieved bootstrap sync committee does not match saved bootstrap sync committee")
-		savedBranch, err := bootstrap.CurrentSyncCommitteeBranch()
-		require.NoError(t, err)
-		retrievedBranch, err := retrievedBootstrap.CurrentSyncCommitteeBranch()
-		require.NoError(t, err)
-		require.DeepEqual(t, savedBranch, retrievedBranch, "retrieved bootstrap sync committee branch does not match saved bootstrap sync committee branch")
-	})
-
-	t.Run("Electra", func(t *testing.T) {
-		bootstrap, err := createDefaultLightClientBootstrap(primitives.Slot(uint64(params.BeaconConfig().ElectraForkEpoch) * uint64(params.BeaconConfig().SlotsPerEpoch)))
-		require.NoError(t, err)
-
-		err = bootstrap.SetCurrentSyncCommittee(createRandomSyncCommittee())
-		require.NoError(t, err)
-
-		err = db.SaveLightClientBootstrap(ctx, []byte("blockRootElectra"), bootstrap)
-		require.NoError(t, err)
-
-		retrievedBootstrap, err := db.LightClientBootstrap(ctx, []byte("blockRootElectra"))
-		require.NoError(t, err)
-		require.DeepEqual(t, bootstrap.Header(), retrievedBootstrap.Header(), "retrieved bootstrap header does not match saved bootstrap header")
-		require.DeepEqual(t, bootstrap.CurrentSyncCommittee(), retrievedBootstrap.CurrentSyncCommittee(), "retrieved bootstrap sync committee does not match saved bootstrap sync committee")
-		savedBranch, err := bootstrap.CurrentSyncCommitteeBranchElectra()
-		require.NoError(t, err)
-		retrievedBranch, err := retrievedBootstrap.CurrentSyncCommitteeBranchElectra()
-		require.NoError(t, err)
-		require.DeepEqual(t, savedBranch, retrievedBranch, "retrieved bootstrap sync committee branch does not match saved bootstrap sync committee branch")
-	})
+			retrievedBootstrap, err := db.LightClientBootstrap(ctx, blockRoot)
+			require.NoError(t, err)
+			require.DeepEqual(t, bootstrap.Header(), retrievedBootstrap.Header(), "retrieved bootstrap header does not match saved bootstrap header")
+			require.DeepEqual(t, bootstrap.CurrentSyncCommittee(), retrievedBootstrap.CurrentSyncCommittee(), "retrieved bootstrap sync committee does not match saved bootstrap sync committee")
+			if testVersion >= version.Electra {
+				savedBranch, err := bootstrap.CurrentSyncCommitteeBranchElectra()
+				require.NoError(t, err)
+				retrievedBranch, err := retrievedBootstrap.CurrentSyncCommitteeBranchElectra()
+				require.NoError(t, err)
+				require.DeepEqual(t, savedBranch, retrievedBranch, "retrieved bootstrap sync committee branch does not match saved bootstrap sync committee branch")
+			} else {
+				savedBranch, err := bootstrap.CurrentSyncCommitteeBranch()
+				require.NoError(t, err)
+				retrievedBranch, err := retrievedBootstrap.CurrentSyncCommitteeBranch()
+				require.NoError(t, err)
+				require.DeepEqual(t, savedBranch, retrievedBranch, "retrieved bootstrap sync committee branch does not match saved bootstrap sync committee branch")
+			}
+		})
+	}
 }
 
 func TestStore_LightClientBootstrap_MultipleBootstrapsWithSameSyncCommittee(t *testing.T) {
@@ -839,6 +770,7 @@ func createDefaultLightClientBootstrap(currentSlot primitives.Slot) (interfaces.
 		m = &pb.LightClientBootstrapAltair{
 			Header: &pb.LightClientHeaderAltair{
 				Beacon: &pb.BeaconBlockHeader{
+					Slot:       currentSlot,
 					ParentRoot: make([]byte, 32),
 					StateRoot:  make([]byte, 32),
 					BodyRoot:   make([]byte, 32),
@@ -851,6 +783,7 @@ func createDefaultLightClientBootstrap(currentSlot primitives.Slot) (interfaces.
 		m = &pb.LightClientBootstrapCapella{
 			Header: &pb.LightClientHeaderCapella{
 				Beacon: &pb.BeaconBlockHeader{
+					Slot:       currentSlot,
 					ParentRoot: make([]byte, 32),
 					StateRoot:  make([]byte, 32),
 					BodyRoot:   make([]byte, 32),
@@ -877,6 +810,7 @@ func createDefaultLightClientBootstrap(currentSlot primitives.Slot) (interfaces.
 		m = &pb.LightClientBootstrapDeneb{
 			Header: &pb.LightClientHeaderDeneb{
 				Beacon: &pb.BeaconBlockHeader{
+					Slot:       currentSlot,
 					ParentRoot: make([]byte, 32),
 					StateRoot:  make([]byte, 32),
 					BodyRoot:   make([]byte, 32),
@@ -905,6 +839,7 @@ func createDefaultLightClientBootstrap(currentSlot primitives.Slot) (interfaces.
 		m = &pb.LightClientBootstrapElectra{
 			Header: &pb.LightClientHeaderDeneb{
 				Beacon: &pb.BeaconBlockHeader{
+					Slot:       currentSlot,
 					ParentRoot: make([]byte, 32),
 					StateRoot:  make([]byte, 32),
 					BodyRoot:   make([]byte, 32),

beacon-chain/execution/BUILD.bazel

@@ -31,6 +31,7 @@ go_library(
         "//beacon-chain/core/feed:go_default_library",
         "//beacon-chain/core/feed/state:go_default_library",
         "//beacon-chain/core/helpers:go_default_library",
+        "//beacon-chain/core/peerdas:go_default_library",
         "//beacon-chain/core/transition:go_default_library",
         "//beacon-chain/db:go_default_library",
         "//beacon-chain/execution/types:go_default_library",
@@ -97,6 +98,7 @@ go_test(
     embed = [":go_default_library"],
     deps = [
         "//async/event:go_default_library",
+        "//beacon-chain/blockchain/kzg:go_default_library",
         "//beacon-chain/cache/depositsnapshot:go_default_library",
         "//beacon-chain/core/feed:go_default_library",
         "//beacon-chain/core/feed/state:go_default_library",

beacon-chain/execution/engine_client.go

@@ -7,6 +7,7 @@ import (
 	"strings"
 	"time"
 
+	"github.com/OffchainLabs/prysm/v6/beacon-chain/core/peerdas"
 	"github.com/OffchainLabs/prysm/v6/beacon-chain/execution/types"
 	"github.com/OffchainLabs/prysm/v6/beacon-chain/verification"
 	fieldparams "github.com/OffchainLabs/prysm/v6/config/fieldparams"
@@ -44,11 +45,18 @@ var (
 		GetPayloadMethodV3,
 		GetPayloadBodiesByHashV1,
 		GetPayloadBodiesByRangeV1,
+		GetBlobsV1,
 	}
+
 	electraEngineEndpoints = []string{
 		NewPayloadMethodV4,
 		GetPayloadMethodV4,
 	}
+
+	fuluEngineEndpoints = []string{
+		GetPayloadMethodV5,
+		GetBlobsV2,
+	}
 )
 
 const (
@@ -73,6 +81,8 @@ const (
 	GetPayloadMethodV3 = "engine_getPayloadV3"
 	// GetPayloadMethodV4 is the get payload method added for electra
 	GetPayloadMethodV4 = "engine_getPayloadV4"
+	// GetPayloadMethodV5 is the get payload method added for fulu
+	GetPayloadMethodV5 = "engine_getPayloadV5"
 	// BlockByHashMethod request string for JSON-RPC.
 	BlockByHashMethod = "eth_getBlockByHash"
 	// BlockByNumberMethod request string for JSON-RPC.
@@ -85,11 +95,16 @@ const (
 	ExchangeCapabilities = "engine_exchangeCapabilities"
 	// GetBlobsV1 request string for JSON-RPC.
 	GetBlobsV1 = "engine_getBlobsV1"
+	// GetBlobsV2 request string for JSON-RPC.
+	GetBlobsV2 = "engine_getBlobsV2"
 	// Defines the seconds before timing out engine endpoints with non-block execution semantics.
 	defaultEngineTimeout = time.Second
 )
 
-var errInvalidPayloadBodyResponse = errors.New("engine api payload body response is invalid")
+var (
+	errInvalidPayloadBodyResponse  = errors.New("engine api payload body response is invalid")
+	errMissingBlobsAndProofsFromEL = errors.New("engine api payload body response is missing blobs and proofs")
+)
 
 // ForkchoiceUpdatedResponse is the response kind received by the
 // engine_forkchoiceUpdatedV1 endpoint.
@@ -107,7 +122,8 @@ type Reconstructor interface {
 	ReconstructFullBellatrixBlockBatch(
 		ctx context.Context, blindedBlocks []interfaces.ReadOnlySignedBeaconBlock,
 	) ([]interfaces.SignedBeaconBlock, error)
-	ReconstructBlobSidecars(ctx context.Context, block interfaces.ReadOnlySignedBeaconBlock, blockRoot [32]byte, hi func(uint64) bool) ([]blocks.VerifiedROBlob, error)
+	ReconstructBlobSidecars(ctx context.Context, block interfaces.ReadOnlySignedBeaconBlock, blockRoot [fieldparams.RootLength]byte, hi func(uint64) bool) ([]blocks.VerifiedROBlob, error)
+	ReconstructDataColumnSidecars(ctx context.Context, block interfaces.ReadOnlySignedBeaconBlock, blockRoot [fieldparams.RootLength]byte) ([]blocks.VerifiedRODataColumn, error)
 }
 
 // EngineCaller defines a client that can interact with an Ethereum
@@ -256,14 +272,17 @@ func (s *Service) ForkchoiceUpdated(
 }
 
 func getPayloadMethodAndMessage(slot primitives.Slot) (string, proto.Message) {
-	pe := slots.ToEpoch(slot)
-	if pe >= params.BeaconConfig().ElectraForkEpoch {
+	epoch := slots.ToEpoch(slot)
+	if epoch >= params.BeaconConfig().FuluForkEpoch {
+		return GetPayloadMethodV5, &pb.ExecutionBundleFulu{}
+	}
+	if epoch >= params.BeaconConfig().ElectraForkEpoch {
 		return GetPayloadMethodV4, &pb.ExecutionBundleElectra{}
 	}
-	if pe >= params.BeaconConfig().DenebForkEpoch {
+	if epoch >= params.BeaconConfig().DenebForkEpoch {
 		return GetPayloadMethodV3, &pb.ExecutionPayloadDenebWithValueAndBlobsBundle{}
 	}
-	if pe >= params.BeaconConfig().CapellaForkEpoch {
+	if epoch >= params.BeaconConfig().CapellaForkEpoch {
 		return GetPayloadMethodV2, &pb.ExecutionPayloadCapellaWithValue{}
 	}
 	return GetPayloadMethod, &pb.ExecutionPayload{}
@@ -289,7 +308,7 @@ func (s *Service) GetPayload(ctx context.Context, payloadId [8]byte, slot primit
 	}
 	res, err := blocks.NewGetPayloadResponse(result)
 	if err != nil {
-		return nil, err
+		return nil, errors.Wrap(err, "new get payload response")
 	}
 	return res, nil
 }
@@ -298,33 +317,36 @@ func (s *Service) ExchangeCapabilities(ctx context.Context) ([]string, error) {
 	ctx, span := trace.StartSpan(ctx, "powchain.engine-api-client.ExchangeCapabilities")
 	defer span.End()
 
-	// Only check for electra related engine methods if it has been activated.
 	if params.ElectraEnabled() {
 		supportedEngineEndpoints = append(supportedEngineEndpoints, electraEngineEndpoints...)
 	}
-	var result []string
-	err := s.rpcClient.CallContext(ctx, &result, ExchangeCapabilities, supportedEngineEndpoints)
-	if err != nil {
+
+	if params.FuluEnabled() {
+		supportedEngineEndpoints = append(supportedEngineEndpoints, fuluEngineEndpoints...)
+	}
+
+	elSupportedEndpointsSlice := make([]string, len(supportedEngineEndpoints))
+	if err := s.rpcClient.CallContext(ctx, &elSupportedEndpointsSlice, ExchangeCapabilities, supportedEngineEndpoints); err != nil {
 		return nil, handleRPCError(err)
 	}
 
-	var unsupported []string
-	for _, s1 := range supportedEngineEndpoints {
-		supported := false
-		for _, s2 := range result {
-			if s1 == s2 {
-				supported = true
-				break
-			}
-		}
-		if !supported {
-			unsupported = append(unsupported, s1)
+	elSupportedEndpoints := make(map[string]bool, len(elSupportedEndpointsSlice))
+	for _, method := range elSupportedEndpointsSlice {
+		elSupportedEndpoints[method] = true
+	}
+
+	unsupported := make([]string, 0)
+	for _, method := range supportedEngineEndpoints {
+		if !elSupportedEndpoints[method] {
+			unsupported = append(unsupported, method)
 		}
 	}
+
 	if len(unsupported) != 0 {
-		log.Warnf("Please update client, detected the following unsupported engine methods: %s", unsupported)
+		log.WithField("methods", unsupported).Warning("Connected execution client does not support some requested engine methods")
 	}
-	return result, handleRPCError(err)
+
+	return elSupportedEndpointsSlice, nil
 }
 
 // GetTerminalBlockHash returns the valid terminal block hash based on total difficulty.
@@ -495,9 +517,10 @@ func (s *Service) HeaderByNumber(ctx context.Context, number *big.Int) (*types.H
 func (s *Service) GetBlobs(ctx context.Context, versionedHashes []common.Hash) ([]*pb.BlobAndProof, error) {
 	ctx, span := trace.StartSpan(ctx, "powchain.engine-api-client.GetBlobs")
 	defer span.End()
+
 	// If the execution engine does not support `GetBlobsV1`, return early to prevent encountering an error later.
 	if !s.capabilityCache.has(GetBlobsV1) {
-		return nil, nil
+		return nil, errors.New(fmt.Sprintf("%s is not supported", GetBlobsV1))
 	}
 
 	result := make([]*pb.BlobAndProof, len(versionedHashes))
@@ -505,6 +528,19 @@ func (s *Service) GetBlobs(ctx context.Context, versionedHashes []common.Hash) (
 	return result, handleRPCError(err)
 }
 
+func (s *Service) GetBlobsV2(ctx context.Context, versionedHashes []common.Hash) ([]*pb.BlobAndProofV2, error) {
+	ctx, span := trace.StartSpan(ctx, "powchain.engine-api-client.GetBlobsV2")
+	defer span.End()
+
+	if !s.capabilityCache.has(GetBlobsV2) {
+		return nil, errors.New(fmt.Sprintf("%s is not supported", GetBlobsV2))
+	}
+
+	result := make([]*pb.BlobAndProofV2, len(versionedHashes))
+	err := s.rpcClient.CallContext(ctx, &result, GetBlobsV2, versionedHashes)
+	return result, handleRPCError(err)
+}
+
 // ReconstructFullBlock takes in a blinded beacon block and reconstructs
 // a beacon block with a full execution payload via the engine API.
 func (s *Service) ReconstructFullBlock(
@@ -615,6 +651,75 @@ func (s *Service) ReconstructBlobSidecars(ctx context.Context, block interfaces.
 	return verifiedBlobs, nil
 }
 
+// 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, signedROBlock interfaces.ReadOnlySignedBeaconBlock, blockRoot [fieldparams.RootLength]byte) ([]blocks.VerifiedRODataColumn, error) {
+	block := signedROBlock.Block()
+
+	log := log.WithFields(logrus.Fields{
+		"root": fmt.Sprintf("%#x", blockRoot),
+		"slot": block.Slot(),
+	})
+
+	kzgCommitments, err := block.Body().BlobKzgCommitments()
+	if err != nil {
+		return nil, wrapWithBlockRoot(err, blockRoot, "blob KZG commitments")
+	}
+
+	// Collect KZG hashes for all blobs.
+	versionedHashes := make([]common.Hash, 0, len(kzgCommitments))
+	for _, commitment := range kzgCommitments {
+		versionedHash := primitives.ConvertKzgCommitmentToVersionedHash(commitment)
+		versionedHashes = append(versionedHashes, versionedHash)
+	}
+
+	// Fetch all blobsAndCellsProofs from the execution client.
+	blobAndProofV2s, err := s.GetBlobsV2(ctx, versionedHashes)
+	if err != nil {
+		return nil, wrapWithBlockRoot(err, blockRoot, "get blobs V2")
+	}
+
+	// Return early if nothing is returned from the EL.
+	if len(blobAndProofV2s) == 0 {
+		log.Debug("No blobs returned from EL")
+		return nil, nil
+	}
+
+	// Extract the blobs and proofs from the blobAndProofV2s.
+	blobs, cellProofs := make([][]byte, 0, len(blobAndProofV2s)), make([][]byte, 0, len(blobAndProofV2s))
+	for _, blobsAndProofs := range blobAndProofV2s {
+		if blobsAndProofs == nil {
+			return nil, wrapWithBlockRoot(errMissingBlobsAndProofsFromEL, blockRoot, "")
+		}
+
+		blobs, cellProofs = append(blobs, blobsAndProofs.Blob), append(cellProofs, blobsAndProofs.KzgProofs...)
+	}
+
+	// Construct the data column sidcars from the blobs and cell proofs provided by the execution client.
+	dataColumnSidecars, err := peerdas.ConstructDataColumnSidecars(signedROBlock, blobs, cellProofs)
+	if err != nil {
+		return nil, wrapWithBlockRoot(err, blockRoot, "construct data column sidecars")
+	}
+
+	// Finally, construct verified RO data column sidecars.
+	// We trust the execution layer we are connected to, so we can upgrade the read only data column sidecar into a verified one.
+	verifiedRODataColumns := make([]blocks.VerifiedRODataColumn, 0, len(dataColumnSidecars))
+	for _, dataColumnSidecar := range dataColumnSidecars {
+		roDataColumn, err := blocks.NewRODataColumnWithRoot(dataColumnSidecar, blockRoot)
+		if err != nil {
+			return nil, wrapWithBlockRoot(err, blockRoot, "new read-only data column with root")
+		}
+
+		verifiedRODataColumn := blocks.NewVerifiedRODataColumn(roDataColumn)
+		verifiedRODataColumns = append(verifiedRODataColumns, verifiedRODataColumn)
+	}
+
+	log.Debug("Data columns successfully reconstructed from the execution client.")
+
+	return verifiedRODataColumns, nil
+}
+
 func fullPayloadFromPayloadBody(
 	header interfaces.ExecutionData, body *pb.ExecutionPayloadBody, bVersion int,
 ) (interfaces.ExecutionData, error) {
@@ -902,3 +1007,8 @@ func toBlockNumArg(number *big.Int) string {
 	}
 	return hexutil.EncodeBig(number)
 }
+
+// wrapWithBlockRoot returns a new error with the given block root.
+func wrapWithBlockRoot(err error, blockRoot [32]byte, message string) error {
+	return errors.Wrap(err, fmt.Sprintf("%s for block %#x", message, blockRoot))
+}

beacon-chain/execution/engine_client_test.go

@@ -13,6 +13,7 @@ import (
 	"strings"
 	"testing"
 
+	"github.com/OffchainLabs/prysm/v6/beacon-chain/blockchain/kzg"
 	"github.com/OffchainLabs/prysm/v6/beacon-chain/db/filesystem"
 	mocks "github.com/OffchainLabs/prysm/v6/beacon-chain/execution/testing"
 	"github.com/OffchainLabs/prysm/v6/beacon-chain/verification"
@@ -167,6 +168,7 @@ func TestClient_HTTP(t *testing.T) {
 	cfg.CapellaForkEpoch = 1
 	cfg.DenebForkEpoch = 2
 	cfg.ElectraForkEpoch = 3
+	cfg.FuluForkEpoch = 4
 	params.OverrideBeaconConfig(cfg)
 
 	t.Run(GetPayloadMethod, func(t *testing.T) {
@@ -317,11 +319,11 @@ func TestClient_HTTP(t *testing.T) {
 		require.DeepEqual(t, uint64(2), g)
 
 		commitments := [][]byte{bytesutil.PadTo([]byte("commitment1"), fieldparams.BLSPubkeyLength), bytesutil.PadTo([]byte("commitment2"), fieldparams.BLSPubkeyLength)}
-		require.DeepEqual(t, commitments, resp.BlobsBundle.KzgCommitments)
+		require.DeepEqual(t, commitments, resp.BlobsBundler.GetKzgCommitments())
 		proofs := [][]byte{bytesutil.PadTo([]byte("proof1"), fieldparams.BLSPubkeyLength), bytesutil.PadTo([]byte("proof2"), fieldparams.BLSPubkeyLength)}
-		require.DeepEqual(t, proofs, resp.BlobsBundle.Proofs)
+		require.DeepEqual(t, proofs, resp.BlobsBundler.GetProofs())
 		blobs := [][]byte{bytesutil.PadTo([]byte("a"), fieldparams.BlobLength), bytesutil.PadTo([]byte("b"), fieldparams.BlobLength)}
-		require.DeepEqual(t, blobs, resp.BlobsBundle.Blobs)
+		require.DeepEqual(t, blobs, resp.BlobsBundler.GetBlobs())
 	})
 	t.Run(GetPayloadMethodV4, func(t *testing.T) {
 		payloadId := [8]byte{1}
@@ -372,11 +374,11 @@ func TestClient_HTTP(t *testing.T) {
 		require.DeepEqual(t, uint64(2), g)
 
 		commitments := [][]byte{bytesutil.PadTo([]byte("commitment1"), fieldparams.BLSPubkeyLength), bytesutil.PadTo([]byte("commitment2"), fieldparams.BLSPubkeyLength)}
-		require.DeepEqual(t, commitments, resp.BlobsBundle.KzgCommitments)
+		require.DeepEqual(t, commitments, resp.BlobsBundler.GetKzgCommitments())
 		proofs := [][]byte{bytesutil.PadTo([]byte("proof1"), fieldparams.BLSPubkeyLength), bytesutil.PadTo([]byte("proof2"), fieldparams.BLSPubkeyLength)}
-		require.DeepEqual(t, proofs, resp.BlobsBundle.Proofs)
+		require.DeepEqual(t, proofs, resp.BlobsBundler.GetProofs())
 		blobs := [][]byte{bytesutil.PadTo([]byte("a"), fieldparams.BlobLength), bytesutil.PadTo([]byte("b"), fieldparams.BlobLength)}
-		require.DeepEqual(t, blobs, resp.BlobsBundle.Blobs)
+		require.DeepEqual(t, blobs, resp.BlobsBundler.GetBlobs())
 		requests := &pb.ExecutionRequests{
 			Deposits: []*pb.DepositRequest{
 				{
@@ -405,7 +407,52 @@ func TestClient_HTTP(t *testing.T) {
 
 		require.DeepEqual(t, requests, resp.ExecutionRequests)
 	})
+	t.Run(GetPayloadMethodV5, func(t *testing.T) {
+		payloadId := [8]byte{1}
+		want, ok := fix["ExecutionBundleFulu"].(*pb.GetPayloadV5ResponseJson)
+		require.Equal(t, true, ok)
+		srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+			w.Header().Set("Content-Type", "application/json")
+			defer func() {
+				require.NoError(t, r.Body.Close())
+			}()
+			enc, err := io.ReadAll(r.Body)
+			require.NoError(t, err)
+			jsonRequestString := string(enc)
 
+			reqArg, err := json.Marshal(pb.PayloadIDBytes(payloadId))
+			require.NoError(t, err)
+
+			// We expect the JSON string RPC request contains the right arguments.
+			require.Equal(t, true, strings.Contains(
+				jsonRequestString, string(reqArg),
+			))
+			resp := map[string]interface{}{
+				"jsonrpc": "2.0",
+				"id":      1,
+				"result":  want,
+			}
+			err = json.NewEncoder(w).Encode(resp)
+			require.NoError(t, err)
+		}))
+		defer srv.Close()
+
+		rpcClient, err := rpc.DialHTTP(srv.URL)
+		require.NoError(t, err)
+		defer rpcClient.Close()
+
+		client := &Service{}
+		client.rpcClient = rpcClient
+
+		// We call the RPC method via HTTP and expect a proper result.
+		resp, err := client.GetPayload(ctx, payloadId, 4*params.BeaconConfig().SlotsPerEpoch)
+		require.NoError(t, err)
+		_, ok = resp.BlobsBundler.(*pb.BlobsBundleV2)
+		if !ok {
+			t.Logf("resp.BlobsBundler has unexpected type: %T", resp.BlobsBundler)
+		}
+		require.Equal(t, ok, true)
+	})
 	t.Run(ForkchoiceUpdatedMethod+" VALID status", func(t *testing.T) {
 		forkChoiceState := &pb.ForkchoiceState{
 			HeadBlockHash:      []byte("head"),
@@ -1539,6 +1586,7 @@ func fixtures() map[string]interface{} {
 		"ExecutionPayloadCapellaWithValue":  s.ExecutionPayloadWithValueCapella,
 		"ExecutionPayloadDenebWithValue":    s.ExecutionPayloadWithValueDeneb,
 		"ExecutionBundleElectra":            s.ExecutionBundleElectra,
+		"ExecutionBundleFulu":               s.ExecutionBundleFulu,
 		"ValidPayloadStatus":                s.ValidPayloadStatus,
 		"InvalidBlockHashStatus":            s.InvalidBlockHashStatus,
 		"AcceptedStatus":                    s.AcceptedStatus,
@@ -1774,6 +1822,36 @@ func fixturesStruct() *payloadFixtures {
 			append([]byte{pb.WithdrawalRequestType}, withdrawalRequestBytes...),
 			append([]byte{pb.ConsolidationRequestType}, consolidationRequestBytes...)},
 	}
+	executionBundleFixtureFulu := &pb.GetPayloadV5ResponseJson{
+		ShouldOverrideBuilder: true,
+		ExecutionPayload: &pb.ExecutionPayloadDenebJSON{
+			ParentHash:    &common.Hash{'a'},
+			FeeRecipient:  &common.Address{'b'},
+			StateRoot:     &common.Hash{'c'},
+			ReceiptsRoot:  &common.Hash{'d'},
+			LogsBloom:     &hexutil.Bytes{'e'},
+			PrevRandao:    &common.Hash{'f'},
+			BaseFeePerGas: "0x123",
+			BlockHash:     &common.Hash{'g'},
+			Transactions:  []hexutil.Bytes{{'h'}},
+			Withdrawals:   []*pb.Withdrawal{},
+			BlockNumber:   &hexUint,
+			GasLimit:      &hexUint,
+			GasUsed:       &hexUint,
+			Timestamp:     &hexUint,
+			BlobGasUsed:   &bgu,
+			ExcessBlobGas: &ebg,
+		},
+		BlockValue: "0x11fffffffff",
+		BlobsBundle: &pb.BlobBundleV2JSON{
+			Commitments: []hexutil.Bytes{[]byte("commitment1"), []byte("commitment2")},
+			Proofs:      []hexutil.Bytes{[]byte("proof1"), []byte("proof2")},
+			Blobs:       []hexutil.Bytes{{'a'}, {'b'}},
+		},
+		ExecutionRequests: []hexutil.Bytes{append([]byte{pb.DepositRequestType}, depositRequestBytes...),
+			append([]byte{pb.WithdrawalRequestType}, withdrawalRequestBytes...),
+			append([]byte{pb.ConsolidationRequestType}, consolidationRequestBytes...)},
+	}
 	parent := bytesutil.PadTo([]byte("parentHash"), fieldparams.RootLength)
 	sha3Uncles := bytesutil.PadTo([]byte("sha3Uncles"), fieldparams.RootLength)
 	miner := bytesutil.PadTo([]byte("miner"), fieldparams.FeeRecipientLength)
@@ -1868,6 +1946,7 @@ func fixturesStruct() *payloadFixtures {
 		ExecutionPayloadWithValueCapella:  executionPayloadWithValueFixtureCapella,
 		ExecutionPayloadWithValueDeneb:    executionPayloadWithValueFixtureDeneb,
 		ExecutionBundleElectra:            executionBundleFixtureElectra,
+		ExecutionBundleFulu:               executionBundleFixtureFulu,
 		ValidPayloadStatus:                validStatus,
 		InvalidBlockHashStatus:            inValidBlockHashStatus,
 		AcceptedStatus:                    acceptedStatus,
@@ -1892,6 +1971,7 @@ type payloadFixtures struct {
 	ExecutionPayloadWithValueCapella  *pb.GetPayloadV2ResponseJson
 	ExecutionPayloadWithValueDeneb    *pb.GetPayloadV3ResponseJson
 	ExecutionBundleElectra            *pb.GetPayloadV4ResponseJson
+	ExecutionBundleFulu               *pb.GetPayloadV5ResponseJson
 	ValidPayloadStatus                *pb.PayloadStatus
 	InvalidBlockHashStatus            *pb.PayloadStatus
 	AcceptedStatus                    *pb.PayloadStatus
@@ -2361,7 +2441,7 @@ func Test_ExchangeCapabilities(t *testing.T) {
 		for _, item := range results {
 			require.NotNil(t, item)
 		}
-		assert.LogsContain(t, logHook, "Please update client, detected the following unsupported engine methods:")
+		assert.LogsContain(t, logHook, "Connected execution client does not support some requested engine methods")
 	})
 	t.Run("list of items", func(t *testing.T) {
 		srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
@@ -2424,7 +2504,7 @@ func TestReconstructBlobSidecars(t *testing.T) {
 	t.Run("get-blobs end point is not supported", func(t *testing.T) {
 		hi := mockSummary(t, []bool{true, true, true, true, true, false})
 		verifiedBlobs, err := client.ReconstructBlobSidecars(ctx, sb, r, hi)
-		require.NoError(t, err)
+		require.ErrorContains(t, "engine_getBlobsV1 is not supported", err)
 		require.Equal(t, 0, len(verifiedBlobs))
 	})
 
@@ -2476,6 +2556,76 @@ func TestReconstructBlobSidecars(t *testing.T) {
 	})
 }
 
+func TestReconstructDataColumnSidecars(t *testing.T) {
+	// Start the trusted setup.
+	err := kzg.Start()
+	require.NoError(t, err)
+
+	// Setup right fork epoch
+	params.SetupTestConfigCleanup(t)
+	cfg := params.BeaconConfig().Copy()
+	cfg.CapellaForkEpoch = 1
+	cfg.DenebForkEpoch = 2
+	cfg.ElectraForkEpoch = 3
+	cfg.FuluForkEpoch = 4
+	params.OverrideBeaconConfig(cfg)
+
+	client := &Service{capabilityCache: &capabilityCache{}}
+	b := util.NewBeaconBlockFulu()
+	b.Block.Slot = 4 * params.BeaconConfig().SlotsPerEpoch
+	kzgCommitments := createRandomKzgCommitments(t, 6)
+	b.Block.Body.BlobKzgCommitments = kzgCommitments
+	r, err := b.Block.HashTreeRoot()
+	require.NoError(t, err)
+	sb, err := blocks.NewSignedBeaconBlock(b)
+	require.NoError(t, err)
+
+	ctx := context.Background()
+
+	t.Run("GetBlobsV2 is not supported", func(t *testing.T) {
+		_, err := client.ReconstructDataColumnSidecars(ctx, sb, r)
+		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)
+		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, 128, len(dataColumns))
+	})
+
+	t.Run("missing some blobs", func(t *testing.T) {
+		blobMasks := []bool{false, true, true, true, true, true}
+		srv := createBlobServerV2(t, 6, blobMasks)
+		defer srv.Close()
+
+		rpcClient, client := setupRpcClientV2(t, srv.URL, client)
+		defer rpcClient.Close()
+
+		dataColumns, err := client.ReconstructDataColumnSidecars(ctx, sb, r)
+		require.ErrorContains(t, errMissingBlobsAndProofsFromEL.Error(), err)
+		require.Equal(t, 0, len(dataColumns))
+	})
+}
+
 func createRandomKzgCommitments(t *testing.T, num int) [][]byte {
 	kzgCommitments := make([][]byte, num)
 	for i := range kzgCommitments {
@@ -2511,6 +2661,42 @@ func createBlobServer(t *testing.T, numBlobs int, callbackFuncs ...func()) *http
 	}))
 }
 
+func createBlobServerV2(t *testing.T, numBlobs int, blobMasks []bool) *httptest.Server {
+	return httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		w.Header().Set("Content-Type", "application/json")
+		defer func() {
+			require.NoError(t, r.Body.Close())
+		}()
+
+		require.Equal(t, len(blobMasks), numBlobs)
+
+		blobAndCellProofs := make([]*pb.BlobAndProofV2Json, numBlobs)
+		for i := range blobAndCellProofs {
+			if !blobMasks[i] {
+				continue
+			}
+
+			blobAndCellProofs[i] = &pb.BlobAndProofV2Json{
+				Blob:      []byte("0xblob"),
+				KzgProofs: []hexutil.Bytes{},
+			}
+			for j := 0; j < int(params.BeaconConfig().NumberOfColumns); j++ {
+				cellProof := make([]byte, 48)
+				blobAndCellProofs[i].KzgProofs = append(blobAndCellProofs[i].KzgProofs, cellProof)
+			}
+		}
+
+		respJSON := map[string]interface{}{
+			"jsonrpc": "2.0",
+			"id":      1,
+			"result":  blobAndCellProofs,
+		}
+
+		err := json.NewEncoder(w).Encode(respJSON)
+		require.NoError(t, err)
+	}))
+}
+
 func setupRpcClient(t *testing.T, url string, client *Service) (*rpc.Client, *Service) {
 	rpcClient, err := rpc.DialHTTP(url)
 	require.NoError(t, err)
@@ -2522,6 +2708,12 @@ func setupRpcClient(t *testing.T, url string, client *Service) (*rpc.Client, *Se
 	return rpcClient, client
 }
 
+func setupRpcClientV2(t *testing.T, url string, client *Service) (*rpc.Client, *Service) {
+	rpcClient, client := setupRpcClient(t, url, client)
+	client.capabilityCache = &capabilityCache{capabilities: map[string]interface{}{GetBlobsV2: nil}}
+	return rpcClient, client
+}
+
 func testNewBlobVerifier() verification.NewBlobVerifier {
 	return func(b blocks.ROBlob, reqs []verification.Requirement) verification.BlobVerifier {
 		return &verification.MockBlobVerifier{

beacon-chain/execution/testing/BUILD.bazel

@@ -17,6 +17,7 @@ go_library(
         "//beacon-chain/execution/types:go_default_library",
         "//beacon-chain/state:go_default_library",
         "//beacon-chain/state/state-native:go_default_library",
+        "//config/fieldparams:go_default_library",
         "//config/params:go_default_library",
         "//consensus-types/blocks:go_default_library",
         "//consensus-types/interfaces:go_default_library",

beacon-chain/execution/testing/mock_engine_client.go

@@ -4,6 +4,7 @@ import (
 	"context"
 	"math/big"
 
+	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"
@@ -38,6 +39,8 @@ type EngineClient struct {
 	ErrGetPayload               error
 	BlobSidecars                []blocks.VerifiedROBlob
 	ErrorBlobSidecars           error
+	DataColumnSidecars          []blocks.VerifiedRODataColumn
+	ErrorDataColumnSidecars     error
 }
 
 // NewPayload --
@@ -109,10 +112,14 @@ func (e *EngineClient) ReconstructFullBellatrixBlockBatch(
 }
 
 // ReconstructBlobSidecars is a mock implementation of the ReconstructBlobSidecars method.
-func (e *EngineClient) ReconstructBlobSidecars(context.Context, interfaces.ReadOnlySignedBeaconBlock, [32]byte, func(uint64) bool) ([]blocks.VerifiedROBlob, error) {
+func (e *EngineClient) ReconstructBlobSidecars(context.Context, interfaces.ReadOnlySignedBeaconBlock, [fieldparams.RootLength]byte, func(uint64) bool) ([]blocks.VerifiedROBlob, error) {
 	return e.BlobSidecars, e.ErrorBlobSidecars
 }
 
+func (e *EngineClient) ReconstructDataColumnSidecars(context.Context, interfaces.ReadOnlySignedBeaconBlock, [fieldparams.RootLength]byte) ([]blocks.VerifiedRODataColumn, error) {
+	return e.DataColumnSidecars, e.ErrorDataColumnSidecars
+}
+
 // GetTerminalBlockHash --
 func (e *EngineClient) GetTerminalBlockHash(ctx context.Context, transitionTime uint64) ([]byte, bool, error) {
 	ttd := new(big.Int)

beacon-chain/node/node.go

@@ -167,7 +167,6 @@ func New(cliCtx *cli.Context, cancel context.CancelFunc, opts ...Option) (*Beaco
 		syncChecker:             &initialsync.SyncChecker{},
 		custodyInfo:             &peerdas.CustodyInfo{},
 		slasherEnabled:          cliCtx.Bool(flags.SlasherFlag.Name),
-		lcStore:                 &lightclient.Store{},
 	}
 
 	for _, opt := range opts {
@@ -235,6 +234,10 @@ func New(cliCtx *cli.Context, cancel context.CancelFunc, opts ...Option) (*Beaco
 	// their initialization.
 	beacon.finalizedStateAtStartUp = nil
 
+	if features.Get().EnableLightClient {
+		beacon.lcStore = lightclient.NewLightClientStore()
+	}
+
 	return beacon, nil
 }
 
@@ -883,8 +886,10 @@ func (b *BeaconNode) registerSyncService(initialSyncComplete chan struct{}, bFil
 		regularsync.WithDataColumnStorage(b.DataColumnStorage),
 		regularsync.WithVerifierWaiter(b.verifyInitWaiter),
 		regularsync.WithAvailableBlocker(bFillStore),
+		regularsync.WithCustodyInfo(b.custodyInfo),
 		regularsync.WithSlasherEnabled(b.slasherEnabled),
 		regularsync.WithLightClientStore(b.lcStore),
+		regularsync.WithBatchVerifierLimit(b.cliCtx.Int(flags.BatchVerifierLimit.Name)),
 	)
 	return b.services.RegisterService(rs)
 }

beacon-chain/p2p/peers/status.go

@@ -705,31 +705,46 @@ func (p *Status) deprecatedPrune() {
 	p.tallyIPTracker()
 }
 
-// BestFinalized returns the highest finalized epoch equal to or higher than ours that is agreed
-// upon by the majority of peers. This method may not return the absolute highest finalized, but
-// the finalized epoch in which most peers can serve blocks (plurality voting).
-// Ideally, all peers would be reporting the same finalized epoch but some may be behind due to their
-// own latency, or because of their finalized epoch at the time we queried them.
-// Returns epoch number and list of peers that are at or beyond that epoch.
+// BestFinalized returns the highest finalized epoch equal to or higher than `ourFinalizedEpoch`
+// that is agreed upon by the majority of peers, and the peers agreeing on this finalized epoch.
+// This method may not return the absolute highest finalized epoch, but the finalized epoch in which
+// most peers can serve blocks (plurality voting). Ideally, all peers would be reporting the same
+// finalized epoch but some may be behind due to their own latency, or because of their finalized
+// epoch at the time we queried them.
 func (p *Status) BestFinalized(maxPeers int, ourFinalizedEpoch primitives.Epoch) (primitives.Epoch, []peer.ID) {
+	// Retrieve all connected peers.
 	connected := p.Connected()
+
+	// key: finalized epoch, value: number of peers that support this finalized epoch.
 	finalizedEpochVotes := make(map[primitives.Epoch]uint64)
+
+	// key: peer ID, value: finalized epoch of the peer.
 	pidEpoch := make(map[peer.ID]primitives.Epoch, len(connected))
+
+	// key: peer ID, value: head slot of the peer.
 	pidHead := make(map[peer.ID]primitives.Slot, len(connected))
+
 	potentialPIDs := make([]peer.ID, 0, len(connected))
 	for _, pid := range connected {
 		peerChainState, err := p.ChainState(pid)
-		if err == nil && peerChainState != nil && peerChainState.FinalizedEpoch >= ourFinalizedEpoch {
-			finalizedEpochVotes[peerChainState.FinalizedEpoch]++
-			pidEpoch[pid] = peerChainState.FinalizedEpoch
-			potentialPIDs = append(potentialPIDs, pid)
-			pidHead[pid] = peerChainState.HeadSlot
+
+		// Skip if the peer's finalized epoch is not defined, or if the peer's finalized epoch is
+		// lower than ours.
+		if err != nil || peerChainState == nil || peerChainState.FinalizedEpoch < ourFinalizedEpoch {
+			continue
 		}
+
+		finalizedEpochVotes[peerChainState.FinalizedEpoch]++
+
+		pidEpoch[pid] = peerChainState.FinalizedEpoch
+		pidHead[pid] = peerChainState.HeadSlot
+
+		potentialPIDs = append(potentialPIDs, pid)
 	}
 
 	// Select the target epoch, which is the epoch most peers agree upon.
-	var targetEpoch primitives.Epoch
-	var mostVotes uint64
+	// If there is a tie, select the highest epoch.
+	targetEpoch, mostVotes := primitives.Epoch(0), uint64(0)
 	for epoch, count := range finalizedEpochVotes {
 		if count > mostVotes || (count == mostVotes && epoch > targetEpoch) {
 			mostVotes = count
@@ -737,11 +752,12 @@ func (p *Status) BestFinalized(maxPeers int, ourFinalizedEpoch primitives.Epoch)
 		}
 	}
 
-	// Sort PIDs by finalized epoch, in decreasing order.
+	// Sort PIDs by finalized (epoch, head), in decreasing order.
 	sort.Slice(potentialPIDs, func(i, j int) bool {
 		if pidEpoch[potentialPIDs[i]] == pidEpoch[potentialPIDs[j]] {
 			return pidHead[potentialPIDs[i]] > pidHead[potentialPIDs[j]]
 		}
+
 		return pidEpoch[potentialPIDs[i]] > pidEpoch[potentialPIDs[j]]
 	})
 
@@ -765,25 +781,36 @@ func (p *Status) BestFinalized(maxPeers int, ourFinalizedEpoch primitives.Epoch)
 // and is shared by at least minPeers.
 func (p *Status) BestNonFinalized(minPeers int, ourHeadEpoch primitives.Epoch) (primitives.Epoch, []peer.ID) {
 	connected := p.Connected()
-	epochVotes := make(map[primitives.Epoch]uint64)
-	pidEpoch := make(map[peer.ID]primitives.Epoch, len(connected))
-	pidHead := make(map[peer.ID]primitives.Slot, len(connected))
-	potentialPIDs := make([]peer.ID, 0, len(connected))
+	slotsPerEpoch := params.BeaconConfig().SlotsPerEpoch
+	ourHeadSlot := slotsPerEpoch.Mul(uint64(ourHeadEpoch))
 
-	ourHeadSlot := params.BeaconConfig().SlotsPerEpoch.Mul(uint64(ourHeadEpoch))
+	// key: head epoch, value: number of peers that support this epoch.
+	epochVotes := make(map[primitives.Epoch]uint64)
+
+	// key: peer ID, value: head epoch of the peer.
+	pidEpoch := make(map[peer.ID]primitives.Epoch, len(connected))
+
+	// key: peer ID, value: head slot of the peer.
+	pidHead := make(map[peer.ID]primitives.Slot, len(connected))
+
+	potentialPIDs := make([]peer.ID, 0, len(connected))
 	for _, pid := range connected {
 		peerChainState, err := p.ChainState(pid)
-		if err == nil && peerChainState != nil && peerChainState.HeadSlot > ourHeadSlot {
-			epoch := slots.ToEpoch(peerChainState.HeadSlot)
-			epochVotes[epoch]++
-			pidEpoch[pid] = epoch
-			pidHead[pid] = peerChainState.HeadSlot
-			potentialPIDs = append(potentialPIDs, pid)
+		// Skip if the peer's head epoch is not defined, or if the peer's head slot is
+		// lower or equal than ours.
+		if err != nil || peerChainState == nil || peerChainState.HeadSlot <= ourHeadSlot {
+			continue
 		}
+
+		epoch := slots.ToEpoch(peerChainState.HeadSlot)
+		epochVotes[epoch]++
+		pidEpoch[pid] = epoch
+		pidHead[pid] = peerChainState.HeadSlot
+		potentialPIDs = append(potentialPIDs, pid)
 	}
 
 	// Select the target epoch, which has enough peers' votes (>= minPeers).
-	var targetEpoch primitives.Epoch
+	targetEpoch := primitives.Epoch(0)
 	for epoch, votes := range epochVotes {
 		if votes >= uint64(minPeers) && targetEpoch < epoch {
 			targetEpoch = epoch
@@ -1019,7 +1046,10 @@ func (p *Status) isfromBadIP(pid peer.ID) error {
 
 	if val, ok := p.ipTracker[ip.String()]; ok {
 		if val > CollocationLimit {
-			return errors.Errorf("collocation limit exceeded: got %d - limit %d", val, CollocationLimit)
+			return errors.Errorf(
+				"colocation limit exceeded: got %d - limit %d for peer %v with IP %v",
+				val, CollocationLimit, pid, ip.String(),
+			)
 		}
 	}
 

beacon-chain/p2p/rpc_topic_mappings.go

@@ -22,50 +22,52 @@ const (
 	SchemaVersionV3 = "/3"
 )
 
-// Specifies the protocol prefix for all our Req/Resp topics.
-const protocolPrefix = "/eth2/beacon_chain/req"
+const (
+	// Specifies the protocol prefix for all our Req/Resp topics.
+	protocolPrefix = "/eth2/beacon_chain/req"
 
-// StatusMessageName specifies the name for the status message topic.
-const StatusMessageName = "/status"
+	// StatusMessageName specifies the name for the status message topic.
+	StatusMessageName = "/status"
 
-// GoodbyeMessageName specifies the name for the goodbye message topic.
-const GoodbyeMessageName = "/goodbye"
+	// GoodbyeMessageName specifies the name for the goodbye message topic.
+	GoodbyeMessageName = "/goodbye"
 
-// BeaconBlocksByRangeMessageName specifies the name for the beacon blocks by range message topic.
-const BeaconBlocksByRangeMessageName = "/beacon_blocks_by_range"
+	// BeaconBlocksByRangeMessageName specifies the name for the beacon blocks by range message topic.
+	BeaconBlocksByRangeMessageName = "/beacon_blocks_by_range"
 
-// BeaconBlocksByRootsMessageName specifies the name for the beacon blocks by root message topic.
-const BeaconBlocksByRootsMessageName = "/beacon_blocks_by_root"
+	// BeaconBlocksByRootsMessageName specifies the name for the beacon blocks by root message topic.
+	BeaconBlocksByRootsMessageName = "/beacon_blocks_by_root"
 
-// PingMessageName Specifies the name for the ping message topic.
-const PingMessageName = "/ping"
+	// PingMessageName Specifies the name for the ping message topic.
+	PingMessageName = "/ping"
 
-// MetadataMessageName specifies the name for the metadata message topic.
-const MetadataMessageName = "/metadata"
+	// MetadataMessageName specifies the name for the metadata message topic.
+	MetadataMessageName = "/metadata"
 
-// BlobSidecarsByRangeName is the name for the BlobSidecarsByRange v1 message topic.
-const BlobSidecarsByRangeName = "/blob_sidecars_by_range"
+	// BlobSidecarsByRangeName is the name for the BlobSidecarsByRange v1 message topic.
+	BlobSidecarsByRangeName = "/blob_sidecars_by_range"
 
-// BlobSidecarsByRootName is the name for the BlobSidecarsByRoot v1 message topic.
-const BlobSidecarsByRootName = "/blob_sidecars_by_root"
+	// BlobSidecarsByRootName is the name for the BlobSidecarsByRoot v1 message topic.
+	BlobSidecarsByRootName = "/blob_sidecars_by_root"
 
-// LightClientBootstrapName is the name for the LightClientBootstrap message topic,
-const LightClientBootstrapName = "/light_client_bootstrap"
+	// LightClientBootstrapName is the name for the LightClientBootstrap message topic,
+	LightClientBootstrapName = "/light_client_bootstrap"
 
-// LightClientUpdatesByRangeName is the name for the LightClientUpdatesByRange topic.
-const LightClientUpdatesByRangeName = "/light_client_updates_by_range"
+	// LightClientUpdatesByRangeName is the name for the LightClientUpdatesByRange topic.
+	LightClientUpdatesByRangeName = "/light_client_updates_by_range"
 
-// LightClientFinalityUpdateName is the name for the LightClientFinalityUpdate topic.
-const LightClientFinalityUpdateName = "/light_client_finality_update"
+	// LightClientFinalityUpdateName is the name for the LightClientFinalityUpdate topic.
+	LightClientFinalityUpdateName = "/light_client_finality_update"
 
-// LightClientOptimisticUpdateName is the name for the LightClientOptimisticUpdate topic.
-const LightClientOptimisticUpdateName = "/light_client_optimistic_update"
+	// LightClientOptimisticUpdateName is the name for the LightClientOptimisticUpdate topic.
+	LightClientOptimisticUpdateName = "/light_client_optimistic_update"
 
-// DataColumnSidecarsByRootName is the name for the DataColumnSidecarsByRoot v1 message topic.
-const DataColumnSidecarsByRootName = "/data_column_sidecars_by_root"
+	// DataColumnSidecarsByRootName is the name for the DataColumnSidecarsByRoot v1 message topic.
+	DataColumnSidecarsByRootName = "/data_column_sidecars_by_root"
 
-// DataColumnSidecarsByRangeName is the name for the DataColumnSidecarsByRange v1 message topic.
-const DataColumnSidecarsByRangeName = "/data_column_sidecars_by_range"
+	// DataColumnSidecarsByRangeName is the name for the DataColumnSidecarsByRange v1 message topic.
+	DataColumnSidecarsByRangeName = "/data_column_sidecars_by_range"
+)
 
 const (
 	// V1 RPC Topics
@@ -101,6 +103,9 @@ const (
 	// RPCDataColumnSidecarsByRootTopicV1 is a topic for requesting data column sidecars by their block root.
 	// /eth2/beacon_chain/req/data_column_sidecars_by_root/1 - New in Fulu.
 	RPCDataColumnSidecarsByRootTopicV1 = protocolPrefix + DataColumnSidecarsByRootName + SchemaVersionV1
+	// RPCDataColumnSidecarsByRangeTopicV1 is a topic for requesting data column sidecars by their slot.
+	// /eth2/beacon_chain/req/data_column_sidecars_by_range/1 - New in Fulu.
+	RPCDataColumnSidecarsByRangeTopicV1 = protocolPrefix + DataColumnSidecarsByRangeName + SchemaVersionV1
 
 	// V2 RPC Topics
 	// RPCBlocksByRangeTopicV2 defines v2 the topic for the blocks by range rpc method.
@@ -121,91 +126,103 @@ const (
 )
 
 // RPCTopicMappings map the base message type to the rpc request.
-var RPCTopicMappings = map[string]interface{}{
-	// RPC Status Message
-	RPCStatusTopicV1: new(pb.Status),
-	// RPC Goodbye Message
-	RPCGoodByeTopicV1: new(primitives.SSZUint64),
-	// RPC Block By Range Message
-	RPCBlocksByRangeTopicV1: new(pb.BeaconBlocksByRangeRequest),
-	RPCBlocksByRangeTopicV2: new(pb.BeaconBlocksByRangeRequest),
-	// RPC Block By Root Message
-	RPCBlocksByRootTopicV1: new(p2ptypes.BeaconBlockByRootsReq),
-	RPCBlocksByRootTopicV2: new(p2ptypes.BeaconBlockByRootsReq),
-	// RPC Ping Message
-	RPCPingTopicV1: new(primitives.SSZUint64),
-	// RPC Metadata Message
-	RPCMetaDataTopicV1: new(interface{}),
-	RPCMetaDataTopicV2: new(interface{}),
-	RPCMetaDataTopicV3: new(interface{}),
-	// BlobSidecarsByRange v1 Message
-	RPCBlobSidecarsByRangeTopicV1: new(pb.BlobSidecarsByRangeRequest),
-	// BlobSidecarsByRoot v1 Message
-	RPCBlobSidecarsByRootTopicV1: new(p2ptypes.BlobSidecarsByRootReq),
+var (
+	RPCTopicMappings = map[string]interface{}{
+		// RPC Status Message
+		RPCStatusTopicV1: new(pb.Status),
 
-	// Light client
-	RPCLightClientBootstrapTopicV1:        new([fieldparams.RootLength]byte),
-	RPCLightClientUpdatesByRangeTopicV1:   new(pb.LightClientUpdatesByRangeRequest),
-	RPCLightClientFinalityUpdateTopicV1:   new(interface{}),
-	RPCLightClientOptimisticUpdateTopicV1: new(interface{}),
+		// RPC Goodbye Message
+		RPCGoodByeTopicV1: new(primitives.SSZUint64),
 
-	// DataColumnSidecarsByRoot v1 Message
-	RPCDataColumnSidecarsByRootTopicV1: new(p2ptypes.DataColumnsByRootIdentifiers),
-}
+		// RPC Block By Range Message
+		RPCBlocksByRangeTopicV1: new(pb.BeaconBlocksByRangeRequest),
+		RPCBlocksByRangeTopicV2: new(pb.BeaconBlocksByRangeRequest),
 
-// Maps all registered protocol prefixes.
-var protocolMapping = map[string]bool{
-	protocolPrefix: true,
-}
+		// RPC Block By Root Message
+		RPCBlocksByRootTopicV1: new(p2ptypes.BeaconBlockByRootsReq),
+		RPCBlocksByRootTopicV2: new(p2ptypes.BeaconBlockByRootsReq),
 
-// Maps all the protocol message names for the different rpc
-// topics.
-var messageMapping = map[string]bool{
-	StatusMessageName:               true,
-	GoodbyeMessageName:              true,
-	BeaconBlocksByRangeMessageName:  true,
-	BeaconBlocksByRootsMessageName:  true,
-	PingMessageName:                 true,
-	MetadataMessageName:             true,
-	BlobSidecarsByRangeName:         true,
-	BlobSidecarsByRootName:          true,
-	LightClientBootstrapName:        true,
-	LightClientUpdatesByRangeName:   true,
-	LightClientFinalityUpdateName:   true,
-	LightClientOptimisticUpdateName: true,
-	DataColumnSidecarsByRootName:    true,
-}
+		// RPC Ping Message
+		RPCPingTopicV1: new(primitives.SSZUint64),
 
-// Maps all the RPC messages which are to updated in altair.
-var altairMapping = map[string]bool{
-	BeaconBlocksByRangeMessageName: true,
-	BeaconBlocksByRootsMessageName: true,
-	MetadataMessageName:            true,
-}
+		// RPC Metadata Message
+		RPCMetaDataTopicV1: new(interface{}),
+		RPCMetaDataTopicV2: new(interface{}),
+		RPCMetaDataTopicV3: new(interface{}),
 
-// Maps all the RPC messages which are to updated in fulu.
-var fuluMapping = map[string]bool{
-	MetadataMessageName: true,
-}
+		// BlobSidecarsByRange v1 Message
+		RPCBlobSidecarsByRangeTopicV1: new(pb.BlobSidecarsByRangeRequest),
 
-var versionMapping = map[string]bool{
-	SchemaVersionV1: true,
-	SchemaVersionV2: true,
-	SchemaVersionV3: true,
-}
+		// BlobSidecarsByRoot v1 Message
+		RPCBlobSidecarsByRootTopicV1: new(p2ptypes.BlobSidecarsByRootReq),
 
-// OmitContextBytesV1 keeps track of which RPC methods do not write context bytes in their v1 incarnations.
-// Phase0 did not have the notion of context bytes, which prefix wire-encoded values with a [4]byte identifier
-// to convey the schema for the receiver to use. These RPCs had a version bump to V2 when the context byte encoding
-// was introduced. For other RPC methods, context bytes are always required.
-var OmitContextBytesV1 = map[string]bool{
-	StatusMessageName:              true,
-	GoodbyeMessageName:             true,
-	BeaconBlocksByRangeMessageName: true,
-	BeaconBlocksByRootsMessageName: true,
-	PingMessageName:                true,
-	MetadataMessageName:            true,
-}
+		// Light client
+		RPCLightClientBootstrapTopicV1:        new([fieldparams.RootLength]byte),
+		RPCLightClientUpdatesByRangeTopicV1:   new(pb.LightClientUpdatesByRangeRequest),
+		RPCLightClientFinalityUpdateTopicV1:   new(interface{}),
+		RPCLightClientOptimisticUpdateTopicV1: new(interface{}),
+
+		// DataColumnSidecarsByRange v1 Message
+		RPCDataColumnSidecarsByRangeTopicV1: new(pb.DataColumnSidecarsByRangeRequest),
+
+		// DataColumnSidecarsByRoot v1 Message
+		RPCDataColumnSidecarsByRootTopicV1: new(p2ptypes.DataColumnsByRootIdentifiers),
+	}
+
+	// Maps all registered protocol prefixes.
+	protocolMapping = map[string]bool{
+		protocolPrefix: true,
+	}
+
+	// Maps all the protocol message names for the different rpc topics.
+	messageMapping = map[string]bool{
+		StatusMessageName:               true,
+		GoodbyeMessageName:              true,
+		BeaconBlocksByRangeMessageName:  true,
+		BeaconBlocksByRootsMessageName:  true,
+		PingMessageName:                 true,
+		MetadataMessageName:             true,
+		BlobSidecarsByRangeName:         true,
+		BlobSidecarsByRootName:          true,
+		LightClientBootstrapName:        true,
+		LightClientUpdatesByRangeName:   true,
+		LightClientFinalityUpdateName:   true,
+		LightClientOptimisticUpdateName: true,
+		DataColumnSidecarsByRootName:    true,
+		DataColumnSidecarsByRangeName:   true,
+	}
+
+	// Maps all the RPC messages which are to updated in altair.
+	altairMapping = map[string]string{
+		BeaconBlocksByRangeMessageName: SchemaVersionV2,
+		BeaconBlocksByRootsMessageName: SchemaVersionV2,
+		MetadataMessageName:            SchemaVersionV2,
+	}
+
+	// Maps all the RPC messages which are to updated in fulu.
+	fuluMapping = map[string]string{
+		MetadataMessageName: SchemaVersionV3,
+	}
+
+	versionMapping = map[string]bool{
+		SchemaVersionV1: true,
+		SchemaVersionV2: true,
+		SchemaVersionV3: true,
+	}
+
+	// OmitContextBytesV1 keeps track of which RPC methods do not write context bytes in their v1 incarnations.
+	// Phase0 did not have the notion of context bytes, which prefix wire-encoded values with a [4]byte identifier
+	// to convey the schema for the receiver to use. These RPCs had a version bump to V2 when the context byte encoding
+	// was introduced. For other RPC methods, context bytes are always required.
+	OmitContextBytesV1 = map[string]bool{
+		StatusMessageName:              true,
+		GoodbyeMessageName:             true,
+		BeaconBlocksByRangeMessageName: true,
+		BeaconBlocksByRootsMessageName: true,
+		PingMessageName:                true,
+		MetadataMessageName:            true,
+	}
+)
 
 // VerifyTopicMapping verifies that the topic and its accompanying
 // message type is correct.
@@ -327,13 +344,17 @@ func TopicFromMessage(msg string, epoch primitives.Epoch) (string, error) {
 	beaconConfig := params.BeaconConfig()
 
 	// Check if the message is to be updated in fulu.
-	if epoch >= beaconConfig.FuluForkEpoch && fuluMapping[msg] {
-		return protocolPrefix + msg + SchemaVersionV3, nil
+	if epoch >= beaconConfig.FuluForkEpoch {
+		if version, ok := fuluMapping[msg]; ok {
+			return protocolPrefix + msg + version, nil
+		}
 	}
 
 	// Check if the message is to be updated in altair.
-	if epoch >= beaconConfig.AltairForkEpoch && altairMapping[msg] {
-		return protocolPrefix + msg + SchemaVersionV2, nil
+	if epoch >= beaconConfig.AltairForkEpoch {
+		if version, ok := altairMapping[msg]; ok {
+			return protocolPrefix + msg + version, nil
+		}
 	}
 
 	return protocolPrefix + msg + SchemaVersionV1, nil

beacon-chain/p2p/rpc_topic_mappings_test.go

@@ -119,50 +119,31 @@ func TestTopicFromMessage_CorrectType(t *testing.T) {
 	})
 
 	t.Run("after altair fork but before fulu fork", func(t *testing.T) {
-		for m := range messageMapping {
-			topic, err := TopicFromMessage(m, altairForkEpoch)
-			require.NoError(t, err)
+		// Not modified in altair fork.
+		topic, err := TopicFromMessage(GoodbyeMessageName, altairForkEpoch)
+		require.NoError(t, err)
+		require.Equal(t, "/eth2/beacon_chain/req/goodbye/1", topic)
 
-			if altairMapping[m] {
-				require.Equal(t, true, strings.Contains(topic, SchemaVersionV2))
-				_, _, version, err := TopicDeconstructor(topic)
-				require.NoError(t, err)
-				require.Equal(t, SchemaVersionV2, version)
-				continue
-			}
-
-			require.Equal(t, true, strings.Contains(topic, SchemaVersionV1))
-			_, _, version, err := TopicDeconstructor(topic)
-			require.NoError(t, err)
-			require.Equal(t, SchemaVersionV1, version)
-		}
+		// Modified in altair fork.
+		topic, err = TopicFromMessage(MetadataMessageName, altairForkEpoch)
+		require.NoError(t, err)
+		require.Equal(t, "/eth2/beacon_chain/req/metadata/2", topic)
 	})
 
 	t.Run("after fulu fork", func(t *testing.T) {
-		for m := range messageMapping {
-			topic, err := TopicFromMessage(m, fuluForkEpoch)
-			require.NoError(t, err)
+		// Not modified in any fork.
+		topic, err := TopicFromMessage(GoodbyeMessageName, fuluForkEpoch)
+		require.NoError(t, err)
+		require.Equal(t, "/eth2/beacon_chain/req/goodbye/1", topic)
 
-			if fuluMapping[m] {
-				require.Equal(t, true, strings.Contains(topic, SchemaVersionV3))
-				_, _, version, err := TopicDeconstructor(topic)
-				require.NoError(t, err)
-				require.Equal(t, SchemaVersionV3, version)
-				continue
-			}
+		// Modified in altair fork.
+		topic, err = TopicFromMessage(BeaconBlocksByRangeMessageName, fuluForkEpoch)
+		require.NoError(t, err)
+		require.Equal(t, "/eth2/beacon_chain/req/beacon_blocks_by_range/2", topic)
 
-			if altairMapping[m] {
-				require.Equal(t, true, strings.Contains(topic, SchemaVersionV2))
-				_, _, version, err := TopicDeconstructor(topic)
-				require.NoError(t, err)
-				require.Equal(t, SchemaVersionV2, version)
-				continue
-			}
-
-			require.Equal(t, true, strings.Contains(topic, SchemaVersionV1))
-			_, _, version, err := TopicDeconstructor(topic)
-			require.NoError(t, err)
-			require.Equal(t, SchemaVersionV1, version)
-		}
+		// Modified both in altair and fulu fork.
+		topic, err = TopicFromMessage(MetadataMessageName, fuluForkEpoch)
+		require.NoError(t, err)
+		require.Equal(t, "/eth2/beacon_chain/req/metadata/3", topic)
 	})
 }

beacon-chain/p2p/types/types.go

@@ -213,7 +213,7 @@ func (s BlobSidecarsByRootReq) Len() int {
 // ====================================
 // DataColumnsByRootIdentifiers section
 // ====================================
-var _ ssz.Marshaler = (*DataColumnsByRootIdentifiers)(nil)
+var _ ssz.Marshaler = DataColumnsByRootIdentifiers{}
 var _ ssz.Unmarshaler = (*DataColumnsByRootIdentifiers)(nil)
 
 // DataColumnsByRootIdentifiers is used to specify a list of data column targets (root+index) in a DataColumnSidecarsByRoot RPC request.
@@ -275,33 +275,33 @@ func (d *DataColumnsByRootIdentifiers) UnmarshalSSZ(buf []byte) error {
 	return nil
 }
 
-func (d *DataColumnsByRootIdentifiers) MarshalSSZ() ([]byte, error) {
+func (d DataColumnsByRootIdentifiers) MarshalSSZ() ([]byte, error) {
 	var err error
-	count := len(*d)
+	count := len(d)
 	maxSize := params.BeaconConfig().MaxRequestBlocksDeneb
 	if uint64(count) > maxSize {
 		return nil, errors.Errorf("data column identifiers list exceeds max size: %d > %d", count, maxSize)
 	}
 
-	if len(*d) == 0 {
+	if len(d) == 0 {
 		return []byte{}, nil
 	}
 	sizes := make([]uint32, count)
 	valTotal := uint32(0)
-	for i, elem := range *d {
+	for i, elem := range d {
 		if elem == nil {
 			return nil, errors.New("nil item in DataColumnsByRootIdentifiers list")
 		}
 		sizes[i] = uint32(elem.SizeSSZ())
 		valTotal += sizes[i]
 	}
-	offSize := uint32(4 * len(*d))
+	offSize := uint32(4 * len(d))
 	out := make([]byte, offSize, offSize+valTotal)
 	for i := range sizes {
 		binary.LittleEndian.PutUint32(out[i*4:i*4+4], offSize)
 		offSize += sizes[i]
 	}
-	for _, elem := range *d {
+	for _, elem := range d {
 		out, err = elem.MarshalSSZTo(out)
 		if err != nil {
 			return nil, err
@@ -312,7 +312,7 @@ func (d *DataColumnsByRootIdentifiers) MarshalSSZ() ([]byte, error) {
 }
 
 // MarshalSSZTo implements ssz.Marshaler. It appends the serialized DataColumnSidecarsByRootReq value to the provided byte slice.
-func (d *DataColumnsByRootIdentifiers) MarshalSSZTo(dst []byte) ([]byte, error) {
+func (d DataColumnsByRootIdentifiers) MarshalSSZTo(dst []byte) ([]byte, error) {
 	obj, err := d.MarshalSSZ()
 	if err != nil {
 		return nil, err
@@ -321,11 +321,11 @@ func (d *DataColumnsByRootIdentifiers) MarshalSSZTo(dst []byte) ([]byte, error)
 }
 
 // SizeSSZ implements ssz.Marshaler. It returns the size of the serialized representation.
-func (d *DataColumnsByRootIdentifiers) SizeSSZ() int {
+func (d DataColumnsByRootIdentifiers) SizeSSZ() int {
 	size := 0
-	for i := 0; i < len(*d); i++ {
+	for i := 0; i < len(d); i++ {
 		size += 4
-		size += (*d)[i].SizeSSZ()
+		size += (d)[i].SizeSSZ()
 	}
 	return size
 }

beacon-chain/rpc/eth/light-client/BUILD.bazel

@@ -42,9 +42,9 @@ go_test(
         "//beacon-chain/core/helpers:go_default_library",
         "//beacon-chain/core/light-client:go_default_library",
         "//beacon-chain/db/testing:go_default_library",
-        "//beacon-chain/state:go_default_library",
         "//config/fieldparams:go_default_library",
         "//config/params:go_default_library",
+        "//consensus-types/blocks:go_default_library",
         "//consensus-types/interfaces:go_default_library",
         "//consensus-types/light-client:go_default_library",
         "//consensus-types/primitives:go_default_library",

beacon-chain/rpc/lookup/BUILD.bazel

@@ -10,11 +10,13 @@ go_library(
     visibility = ["//visibility:public"],
     deps = [
         "//beacon-chain/blockchain:go_default_library",
+        "//beacon-chain/core/peerdas:go_default_library",
         "//beacon-chain/db:go_default_library",
         "//beacon-chain/db/filesystem:go_default_library",
         "//beacon-chain/rpc/core:go_default_library",
         "//beacon-chain/state:go_default_library",
         "//beacon-chain/state/stategen:go_default_library",
+        "//cmd/beacon-chain/flags:go_default_library",
         "//config/fieldparams:go_default_library",
         "//config/params:go_default_library",
         "//consensus-types/blocks:go_default_library",
@@ -36,7 +38,9 @@ go_test(
     ],
     embed = [":go_default_library"],
     deps = [
+        "//beacon-chain/blockchain/kzg:go_default_library",
         "//beacon-chain/blockchain/testing:go_default_library",
+        "//beacon-chain/core/peerdas:go_default_library",
         "//beacon-chain/db/filesystem:go_default_library",
         "//beacon-chain/db/testing:go_default_library",
         "//beacon-chain/rpc/core:go_default_library",
@@ -45,6 +49,7 @@ go_test(
         "//beacon-chain/state/stategen:go_default_library",
         "//beacon-chain/state/stategen/mock:go_default_library",
         "//beacon-chain/verification:go_default_library",
+        "//config/fieldparams:go_default_library",
         "//config/params:go_default_library",
         "//consensus-types/blocks:go_default_library",
         "//consensus-types/primitives:go_default_library",

beacon-chain/rpc/lookup/blocker.go

@@ -3,12 +3,15 @@ package lookup
 import (
 	"context"
 	"fmt"
+	"math"
 	"strconv"
 
 	"github.com/OffchainLabs/prysm/v6/beacon-chain/blockchain"
+	"github.com/OffchainLabs/prysm/v6/beacon-chain/core/peerdas"
 	"github.com/OffchainLabs/prysm/v6/beacon-chain/db"
 	"github.com/OffchainLabs/prysm/v6/beacon-chain/db/filesystem"
 	"github.com/OffchainLabs/prysm/v6/beacon-chain/rpc/core"
+	"github.com/OffchainLabs/prysm/v6/cmd/beacon-chain/flags"
 	fieldparams "github.com/OffchainLabs/prysm/v6/config/fieldparams"
 	"github.com/OffchainLabs/prysm/v6/config/params"
 	"github.com/OffchainLabs/prysm/v6/consensus-types/blocks"
@@ -49,6 +52,7 @@ type BeaconDbBlocker struct {
 	ChainInfoFetcher   blockchain.ChainInfoFetcher
 	GenesisTimeFetcher blockchain.TimeFetcher
 	BlobStorage        *filesystem.BlobStorage
+	DataColumnStorage  *filesystem.DataColumnStorage
 }
 
 // Block returns the beacon block for a given identifier. The identifier can be one of:
@@ -212,64 +216,190 @@ func (p *BeaconDbBlocker) Blobs(ctx context.Context, id string, indices []int) (
 
 	root := bytesutil.ToBytes32(rootSlice)
 
-	b, err := p.BeaconDB.Block(ctx, root)
+	roSignedBlock, err := p.BeaconDB.Block(ctx, root)
 	if err != nil {
 		return nil, &core.RpcError{Err: errors.Wrapf(err, "failed to retrieve block %#x from db", rootSlice), Reason: core.Internal}
 	}
-	if b == nil {
+
+	if roSignedBlock == nil {
 		return nil, &core.RpcError{Err: fmt.Errorf("block %#x not found in db", rootSlice), Reason: core.NotFound}
 	}
 
-	// if block is not in the retention window, return 200 w/ empty list
-	if !p.BlobStorage.WithinRetentionPeriod(slots.ToEpoch(b.Block().Slot()), slots.ToEpoch(p.GenesisTimeFetcher.CurrentSlot())) {
+	// If block is not in the retention window, return 200 w/ empty list
+	if !p.BlobStorage.WithinRetentionPeriod(slots.ToEpoch(roSignedBlock.Block().Slot()), slots.ToEpoch(p.GenesisTimeFetcher.CurrentSlot())) {
 		return make([]*blocks.VerifiedROBlob, 0), nil
 	}
 
-	commitments, err := b.Block().Body().BlobKzgCommitments()
+	roBlock := roSignedBlock.Block()
+
+	commitments, err := roBlock.Body().BlobKzgCommitments()
 	if err != nil {
 		return nil, &core.RpcError{Err: errors.Wrapf(err, "failed to retrieve kzg commitments from block %#x", rootSlice), Reason: core.Internal}
 	}
-	// if there are no commitments return 200 w/ empty list
+
+	// If there are no commitments return 200 w/ empty list
 	if len(commitments) == 0 {
 		return make([]*blocks.VerifiedROBlob, 0), nil
 	}
 
-	sum := p.BlobStorage.Summary(root)
+	// Compute the first Fulu slot.
+	fuluForkEpoch := params.BeaconConfig().FuluForkEpoch
+	fuluForkSlot := primitives.Slot(math.MaxUint64)
+	if fuluForkEpoch != primitives.Epoch(math.MaxUint64) {
+		fuluForkSlot, err = slots.EpochStart(fuluForkEpoch)
+		if err != nil {
+			return nil, &core.RpcError{Err: errors.Wrap(err, "could not calculate peerDAS start slot"), Reason: core.Internal}
+		}
+	}
 
-	if len(indices) == 0 {
-		for i := range commitments {
-			if sum.HasIndex(uint64(i)) {
-				indices = append(indices, i)
+	if roBlock.Slot() >= fuluForkSlot {
+		roBlock, err := blocks.NewROBlockWithRoot(roSignedBlock, root)
+		if err != nil {
+			return nil, &core.RpcError{Err: errors.Wrapf(err, "failed to create roBlock with root %#x", root), Reason: core.Internal}
+		}
+
+		return p.blobsFromStoredDataColumns(roBlock, indices)
+	}
+
+	return p.blobsFromStoredBlobs(commitments, root, indices)
+}
+
+// blobsFromStoredBlobs retrieves blob sidercars corresponding to `indices` and `root` from the store.
+// This function expects blob sidecars to be stored (aka. no data column sidecars).
+func (p *BeaconDbBlocker) blobsFromStoredBlobs(commitments [][]byte, root [fieldparams.RootLength]byte, indices []int) ([]*blocks.VerifiedROBlob, *core.RpcError) {
+	summary := p.BlobStorage.Summary(root)
+	maxBlobCount := summary.MaxBlobsForEpoch()
+
+	for _, index := range indices {
+		if uint64(index) >= maxBlobCount {
+			return nil, &core.RpcError{
+				Err:    fmt.Errorf("requested index %d is bigger than the maximum possible blob count %d", index, maxBlobCount),
+				Reason: core.BadRequest,
 			}
 		}
-	} else {
-		for _, ix := range indices {
-			if uint64(ix) >= sum.MaxBlobsForEpoch() {
-				return nil, &core.RpcError{
-					Err:    fmt.Errorf("requested index %d is bigger than the maximum possible blob count %d", ix, sum.MaxBlobsForEpoch()),
-					Reason: core.BadRequest,
-				}
-			}
-			if !sum.HasIndex(uint64(ix)) {
-				return nil, &core.RpcError{
-					Err:    fmt.Errorf("requested index %d not found", ix),
-					Reason: core.NotFound,
-				}
+
+		if !summary.HasIndex(uint64(index)) {
+			return nil, &core.RpcError{
+				Err:    fmt.Errorf("requested index %d not found", index),
+				Reason: core.NotFound,
 			}
 		}
 	}
 
-	blobs := make([]*blocks.VerifiedROBlob, len(indices))
-	for i, index := range indices {
-		vblob, err := p.BlobStorage.Get(root, uint64(index))
+	// If no indices are provided, use all indices that are available in the summary.
+	if len(indices) == 0 {
+		for index := range commitments {
+			if summary.HasIndex(uint64(index)) {
+				indices = append(indices, index)
+			}
+		}
+	}
+
+	// Retrieve blob sidecars from the store.
+	blobs := make([]*blocks.VerifiedROBlob, 0, len(indices))
+	for _, index := range indices {
+		blobSidecar, err := p.BlobStorage.Get(root, uint64(index))
 		if err != nil {
 			return nil, &core.RpcError{
-				Err:    fmt.Errorf("could not retrieve blob for block root %#x at index %d", rootSlice, index),
+				Err:    fmt.Errorf("could not retrieve blob for block root %#x at index %d", root, index),
 				Reason: core.Internal,
 			}
 		}
-		blobs[i] = &vblob
+
+		blobs = append(blobs, &blobSidecar)
 	}
 
 	return blobs, nil
 }
+
+// blobsFromStoredDataColumns retrieves data column sidecars from the store,
+// reconstructs the whole matrix if needed, converts the matrix to blobs,
+// and then returns converted blobs corresponding to `indices` and `root`.
+// This function expects data column sidecars to be stored (aka. no blob sidecars).
+// If not enough data column sidecars are available to convert blobs from them
+// (either directly or after reconstruction), an error is returned.
+func (p *BeaconDbBlocker) blobsFromStoredDataColumns(block blocks.ROBlock, indices []int) ([]*blocks.VerifiedROBlob, *core.RpcError) {
+	root := block.Root()
+
+	// Use all indices if none are provided.
+	if len(indices) == 0 {
+		commitments, err := block.Block().Body().BlobKzgCommitments()
+		if err != nil {
+			return nil, &core.RpcError{
+				Err:    errors.Wrap(err, "could not retrieve blob commitments"),
+				Reason: core.Internal,
+			}
+		}
+
+		for index := range commitments {
+			indices = append(indices, index)
+		}
+	}
+
+	// Count how many columns we have in the store.
+	summary := p.DataColumnStorage.Summary(root)
+	stored := summary.Stored()
+	count := uint64(len(stored))
+
+	if count < peerdas.MinimumColumnsCountToReconstruct() {
+		// 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 succeed, or retry later if it is already the case", flags.SubscribeAllDataSubnets.Name),
+			Reason: core.NotFound,
+		}
+	}
+
+	// Retrieve from the database needed data columns.
+	verifiedRoDataColumnSidecars, err := p.neededDataColumnSidecars(root, stored)
+	if err != nil {
+		return nil, &core.RpcError{
+			Err:    errors.Wrap(err, "needed data column sidecars"),
+			Reason: core.Internal,
+		}
+	}
+
+	// Reconstruct blob sidecars from data column sidecars.
+	verifiedRoBlobSidecars, err := peerdas.ReconstructBlobs(block, verifiedRoDataColumnSidecars, indices)
+	if err != nil {
+		return nil, &core.RpcError{
+			Err:    errors.Wrap(err, "blobs from data columns"),
+			Reason: core.Internal,
+		}
+	}
+
+	return verifiedRoBlobSidecars, nil
+}
+
+// neededDataColumnSidecars retrieves all data column sidecars corresponding to (non extended) blobs if available,
+// else retrieves all data column sidecars from the store.
+func (p *BeaconDbBlocker) neededDataColumnSidecars(root [fieldparams.RootLength]byte, stored map[uint64]bool) ([]blocks.VerifiedRODataColumn, error) {
+	// Check if we have all the non-extended data columns.
+	cellsPerBlob := fieldparams.CellsPerBlob
+	blobIndices := make([]uint64, 0, cellsPerBlob)
+	hasAllBlobColumns := true
+	for i := range uint64(cellsPerBlob) {
+		if !stored[i] {
+			hasAllBlobColumns = false
+			break
+		}
+		blobIndices = append(blobIndices, i)
+	}
+
+	if hasAllBlobColumns {
+		// Retrieve only the non-extended data columns.
+		verifiedRoSidecars, err := p.DataColumnStorage.Get(root, blobIndices)
+		if err != nil {
+			return nil, errors.Wrap(err, "data columns storage get")
+		}
+
+		return verifiedRoSidecars, nil
+	}
+
+	// Retrieve all the data columns.
+	verifiedRoSidecars, err := p.DataColumnStorage.Get(root, nil)
+	if err != nil {
+		return nil, errors.Wrap(err, "data columns storage get")
+	}
+
+	return verifiedRoSidecars, nil
+}

beacon-chain/rpc/lookup/blocker_test.go

@@ -8,12 +8,15 @@ import (
 	"testing"
 	"time"
 
+	"github.com/OffchainLabs/prysm/v6/beacon-chain/blockchain/kzg"
 	mockChain "github.com/OffchainLabs/prysm/v6/beacon-chain/blockchain/testing"
+	"github.com/OffchainLabs/prysm/v6/beacon-chain/core/peerdas"
 	"github.com/OffchainLabs/prysm/v6/beacon-chain/db/filesystem"
 	testDB "github.com/OffchainLabs/prysm/v6/beacon-chain/db/testing"
 	"github.com/OffchainLabs/prysm/v6/beacon-chain/rpc/core"
 	"github.com/OffchainLabs/prysm/v6/beacon-chain/rpc/testutil"
 	"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"
 	"github.com/OffchainLabs/prysm/v6/encoding/bytesutil"
@@ -158,172 +161,335 @@ func TestGetBlock(t *testing.T) {
 }
 
 func TestGetBlob(t *testing.T) {
-	params.SetupTestConfigCleanup(t)
-	cfg := params.BeaconConfig().Copy()
-	cfg.DenebForkEpoch = 1
-	params.OverrideBeaconConfig(cfg)
+	const (
+		slot          = 123
+		blobCount     = 4
+		denebForEpoch = 1
+		fuluForkEpoch = 2
+	)
+
+	setupDeneb := func(t *testing.T) {
+		params.SetupTestConfigCleanup(t)
+		cfg := params.BeaconConfig().Copy()
+		cfg.DenebForkEpoch = denebForEpoch
+		params.OverrideBeaconConfig(cfg)
+	}
+
+	setupFulu := func(t *testing.T) {
+		params.SetupTestConfigCleanup(t)
+		cfg := params.BeaconConfig().Copy()
+		cfg.DenebForkEpoch = denebForEpoch
+		cfg.FuluForkEpoch = fuluForkEpoch
+		params.OverrideBeaconConfig(cfg)
+	}
+
 	ctx := t.Context()
 	db := testDB.SetupDB(t)
-	denebBlock, blobs := util.GenerateTestDenebBlockWithSidecar(t, [32]byte{}, 123, 4)
-	require.NoError(t, db.SaveBlock(t.Context(), denebBlock))
-	_, bs := filesystem.NewEphemeralBlobStorageAndFs(t)
-	testSidecars := verification.FakeVerifySliceForTest(t, blobs)
-	for i := range testSidecars {
-		require.NoError(t, bs.Save(testSidecars[i]))
+
+	// Start the trusted setup.
+	err := kzg.Start()
+	require.NoError(t, err)
+
+	// Create and save Deneb block and blob sidecars.
+	_, blobStorage := filesystem.NewEphemeralBlobStorageAndFs(t)
+
+	denebBlock, storedBlobSidecars := util.GenerateTestDenebBlockWithSidecar(t, [fieldparams.RootLength]byte{}, slot, blobCount)
+	denebBlockRoot := denebBlock.Root()
+
+	verifiedStoredSidecars := verification.FakeVerifySliceForTest(t, storedBlobSidecars)
+	for i := range verifiedStoredSidecars {
+		err := blobStorage.Save(verifiedStoredSidecars[i])
+		require.NoError(t, err)
 	}
-	blockRoot := blobs[0].BlockRoot()
+
+	err = db.SaveBlock(t.Context(), denebBlock)
+	require.NoError(t, err)
+
+	// Create Electra block and blob sidecars. (Electra block = Fulu block),
+	// save the block, convert blob sidecars to data column sidecars and save the block.
+	fuluForkSlot := fuluForkEpoch * params.BeaconConfig().SlotsPerEpoch
+	fuluBlock, fuluBlobSidecars := util.GenerateTestElectraBlockWithSidecar(t, [fieldparams.RootLength]byte{}, fuluForkSlot, blobCount)
+	fuluBlockRoot := fuluBlock.Root()
+
+	cellsAndProofsList := make([]kzg.CellsAndProofs, 0, len(fuluBlobSidecars))
+	for _, blob := range fuluBlobSidecars {
+		var kzgBlob kzg.Blob
+		copy(kzgBlob[:], blob.Blob)
+		cellsAndProogs, err := kzg.ComputeCellsAndKZGProofs(&kzgBlob)
+		require.NoError(t, err)
+		cellsAndProofsList = append(cellsAndProofsList, cellsAndProogs)
+	}
+
+	dataColumnSidecarPb, err := peerdas.DataColumnSidecars(fuluBlock, cellsAndProofsList)
+	require.NoError(t, err)
+
+	verifiedRoDataColumnSidecars := make([]blocks.VerifiedRODataColumn, 0, len(dataColumnSidecarPb))
+	for _, sidecarPb := range dataColumnSidecarPb {
+		roDataColumn, err := blocks.NewRODataColumnWithRoot(sidecarPb, fuluBlockRoot)
+		require.NoError(t, err)
+
+		verifiedRoDataColumn := blocks.NewVerifiedRODataColumn(roDataColumn)
+		verifiedRoDataColumnSidecars = append(verifiedRoDataColumnSidecars, verifiedRoDataColumn)
+	}
+
+	err = db.SaveBlock(t.Context(), fuluBlock)
+	require.NoError(t, err)
+
 	t.Run("genesis", func(t *testing.T) {
+		setupDeneb(t)
+
 		blocker := &BeaconDbBlocker{}
 		_, rpcErr := blocker.Blobs(ctx, "genesis", nil)
-		assert.Equal(t, http.StatusBadRequest, core.ErrorReasonToHTTP(rpcErr.Reason))
-		assert.StringContains(t, "blobs are not supported for Phase 0 fork", rpcErr.Err.Error())
+		require.Equal(t, http.StatusBadRequest, core.ErrorReasonToHTTP(rpcErr.Reason))
+		require.StringContains(t, "blobs are not supported for Phase 0 fork", rpcErr.Err.Error())
 	})
+
 	t.Run("head", func(t *testing.T) {
+		setupDeneb(t)
+
 		blocker := &BeaconDbBlocker{
-			ChainInfoFetcher: &mockChain.ChainService{Root: blockRoot[:]},
+			ChainInfoFetcher: &mockChain.ChainService{Root: denebBlockRoot[:]},
 			GenesisTimeFetcher: &testutil.MockGenesisTimeFetcher{
 				Genesis: time.Now(),
 			},
 			BeaconDB:    db,
-			BlobStorage: bs,
+			BlobStorage: blobStorage,
+		}
+
+		retrievedVerifiedSidecars, rpcErr := blocker.Blobs(ctx, "head", nil)
+		require.IsNil(t, rpcErr)
+		require.Equal(t, blobCount, len(retrievedVerifiedSidecars))
+
+		for i := range blobCount {
+			expected := verifiedStoredSidecars[i]
+
+			actual := retrievedVerifiedSidecars[i].BlobSidecar
+			require.NotNil(t, actual)
+
+			require.Equal(t, expected.Index, actual.Index)
+			require.DeepEqual(t, expected.Blob, actual.Blob)
+			require.DeepEqual(t, expected.KzgCommitment, actual.KzgCommitment)
+			require.DeepEqual(t, expected.KzgProof, actual.KzgProof)
 		}
-		verifiedBlobs, rpcErr := blocker.Blobs(ctx, "head", nil)
-		assert.Equal(t, rpcErr == nil, true)
-		require.Equal(t, 4, len(verifiedBlobs))
-		sidecar := verifiedBlobs[0].BlobSidecar
-		require.NotNil(t, sidecar)
-		assert.Equal(t, uint64(0), sidecar.Index)
-		assert.DeepEqual(t, blobs[0].Blob, sidecar.Blob)
-		assert.DeepEqual(t, blobs[0].KzgCommitment, sidecar.KzgCommitment)
-		assert.DeepEqual(t, blobs[0].KzgProof, sidecar.KzgProof)
-		sidecar = verifiedBlobs[1].BlobSidecar
-		require.NotNil(t, sidecar)
-		assert.Equal(t, uint64(1), sidecar.Index)
-		assert.DeepEqual(t, blobs[1].Blob, sidecar.Blob)
-		assert.DeepEqual(t, blobs[1].KzgCommitment, sidecar.KzgCommitment)
-		assert.DeepEqual(t, blobs[1].KzgProof, sidecar.KzgProof)
-		sidecar = verifiedBlobs[2].BlobSidecar
-		require.NotNil(t, sidecar)
-		assert.Equal(t, uint64(2), sidecar.Index)
-		assert.DeepEqual(t, blobs[2].Blob, sidecar.Blob)
-		assert.DeepEqual(t, blobs[2].KzgCommitment, sidecar.KzgCommitment)
-		assert.DeepEqual(t, blobs[2].KzgProof, sidecar.KzgProof)
-		sidecar = verifiedBlobs[3].BlobSidecar
-		require.NotNil(t, sidecar)
-		assert.Equal(t, uint64(3), sidecar.Index)
-		assert.DeepEqual(t, blobs[3].Blob, sidecar.Blob)
-		assert.DeepEqual(t, blobs[3].KzgCommitment, sidecar.KzgCommitment)
-		assert.DeepEqual(t, blobs[3].KzgProof, sidecar.KzgProof)
 	})
+
 	t.Run("finalized", func(t *testing.T) {
+		setupDeneb(t)
+
 		blocker := &BeaconDbBlocker{
-			ChainInfoFetcher: &mockChain.ChainService{FinalizedCheckPoint: &ethpb.Checkpoint{Root: blockRoot[:]}},
+			ChainInfoFetcher: &mockChain.ChainService{FinalizedCheckPoint: &ethpb.Checkpoint{Root: denebBlockRoot[:]}},
 			GenesisTimeFetcher: &testutil.MockGenesisTimeFetcher{
 				Genesis: time.Now(),
 			},
 			BeaconDB:    db,
-			BlobStorage: bs,
+			BlobStorage: blobStorage,
 		}
 
-		verifiedBlobs, rpcErr := blocker.Blobs(ctx, "finalized", nil)
-		assert.Equal(t, rpcErr == nil, true)
-		require.Equal(t, 4, len(verifiedBlobs))
+		verifiedSidecars, rpcErr := blocker.Blobs(ctx, "finalized", nil)
+		require.IsNil(t, rpcErr)
+		require.Equal(t, blobCount, len(verifiedSidecars))
 	})
+
 	t.Run("justified", func(t *testing.T) {
+		setupDeneb(t)
+
 		blocker := &BeaconDbBlocker{
-			ChainInfoFetcher: &mockChain.ChainService{CurrentJustifiedCheckPoint: &ethpb.Checkpoint{Root: blockRoot[:]}},
+			ChainInfoFetcher: &mockChain.ChainService{CurrentJustifiedCheckPoint: &ethpb.Checkpoint{Root: denebBlockRoot[:]}},
 			GenesisTimeFetcher: &testutil.MockGenesisTimeFetcher{
 				Genesis: time.Now(),
 			},
 			BeaconDB:    db,
-			BlobStorage: bs,
+			BlobStorage: blobStorage,
 		}
 
-		verifiedBlobs, rpcErr := blocker.Blobs(ctx, "justified", nil)
-		assert.Equal(t, rpcErr == nil, true)
-		require.Equal(t, 4, len(verifiedBlobs))
+		verifiedSidecars, rpcErr := blocker.Blobs(ctx, "justified", nil)
+		require.IsNil(t, rpcErr)
+		require.Equal(t, blobCount, len(verifiedSidecars))
 	})
+
 	t.Run("root", func(t *testing.T) {
+		setupDeneb(t)
+
 		blocker := &BeaconDbBlocker{
 			GenesisTimeFetcher: &testutil.MockGenesisTimeFetcher{
 				Genesis: time.Now(),
 			},
 			BeaconDB:    db,
-			BlobStorage: bs,
+			BlobStorage: blobStorage,
 		}
-		verifiedBlobs, rpcErr := blocker.Blobs(ctx, hexutil.Encode(blockRoot[:]), nil)
-		assert.Equal(t, rpcErr == nil, true)
-		require.Equal(t, 4, len(verifiedBlobs))
+
+		verifiedBlobs, rpcErr := blocker.Blobs(ctx, hexutil.Encode(denebBlockRoot[:]), nil)
+		require.IsNil(t, rpcErr)
+		require.Equal(t, blobCount, len(verifiedBlobs))
 	})
+
 	t.Run("slot", func(t *testing.T) {
+		setupDeneb(t)
+
 		blocker := &BeaconDbBlocker{
 			GenesisTimeFetcher: &testutil.MockGenesisTimeFetcher{
 				Genesis: time.Now(),
 			},
 			BeaconDB:    db,
-			BlobStorage: bs,
+			BlobStorage: blobStorage,
 		}
+
 		verifiedBlobs, rpcErr := blocker.Blobs(ctx, "123", nil)
-		assert.Equal(t, rpcErr == nil, true)
-		require.Equal(t, 4, len(verifiedBlobs))
+		require.IsNil(t, rpcErr)
+		require.Equal(t, blobCount, len(verifiedBlobs))
 	})
+
 	t.Run("one blob only", func(t *testing.T) {
+		const index = 2
+
+		setupDeneb(t)
+
 		blocker := &BeaconDbBlocker{
-			ChainInfoFetcher: &mockChain.ChainService{FinalizedCheckPoint: &ethpb.Checkpoint{Root: blockRoot[:]}},
+			ChainInfoFetcher: &mockChain.ChainService{FinalizedCheckPoint: &ethpb.Checkpoint{Root: denebBlockRoot[:]}},
 			GenesisTimeFetcher: &testutil.MockGenesisTimeFetcher{
 				Genesis: time.Now(),
 			},
 			BeaconDB:    db,
-			BlobStorage: bs,
+			BlobStorage: blobStorage,
 		}
-		verifiedBlobs, rpcErr := blocker.Blobs(ctx, "123", []int{2})
-		assert.Equal(t, rpcErr == nil, true)
-		require.Equal(t, 1, len(verifiedBlobs))
-		sidecar := verifiedBlobs[0].BlobSidecar
-		require.NotNil(t, sidecar)
-		assert.Equal(t, uint64(2), sidecar.Index)
-		assert.DeepEqual(t, blobs[2].Blob, sidecar.Blob)
-		assert.DeepEqual(t, blobs[2].KzgCommitment, sidecar.KzgCommitment)
-		assert.DeepEqual(t, blobs[2].KzgProof, sidecar.KzgProof)
+
+		retrievedVerifiedSidecars, rpcErr := blocker.Blobs(ctx, "123", []int{index})
+		require.IsNil(t, rpcErr)
+		require.Equal(t, 1, len(retrievedVerifiedSidecars))
+
+		expected := verifiedStoredSidecars[index]
+		actual := retrievedVerifiedSidecars[0].BlobSidecar
+		require.NotNil(t, actual)
+
+		require.Equal(t, uint64(index), actual.Index)
+		require.DeepEqual(t, expected.Blob, actual.Blob)
+		require.DeepEqual(t, expected.KzgCommitment, actual.KzgCommitment)
+		require.DeepEqual(t, expected.KzgProof, actual.KzgProof)
 	})
+
 	t.Run("no blobs returns an empty array", func(t *testing.T) {
+		setupDeneb(t)
+
 		blocker := &BeaconDbBlocker{
-			ChainInfoFetcher: &mockChain.ChainService{FinalizedCheckPoint: &ethpb.Checkpoint{Root: blockRoot[:]}},
+			ChainInfoFetcher: &mockChain.ChainService{FinalizedCheckPoint: &ethpb.Checkpoint{Root: denebBlockRoot[:]}},
 			GenesisTimeFetcher: &testutil.MockGenesisTimeFetcher{
 				Genesis: time.Now(),
 			},
 			BeaconDB:    db,
 			BlobStorage: filesystem.NewEphemeralBlobStorage(t),
 		}
+
 		verifiedBlobs, rpcErr := blocker.Blobs(ctx, "123", nil)
-		assert.Equal(t, rpcErr == nil, true)
+		require.IsNil(t, rpcErr)
 		require.Equal(t, 0, len(verifiedBlobs))
 	})
+
 	t.Run("no blob at index", func(t *testing.T) {
+		setupDeneb(t)
+
 		blocker := &BeaconDbBlocker{
-			ChainInfoFetcher: &mockChain.ChainService{FinalizedCheckPoint: &ethpb.Checkpoint{Root: blockRoot[:]}},
+			ChainInfoFetcher: &mockChain.ChainService{FinalizedCheckPoint: &ethpb.Checkpoint{Root: denebBlockRoot[:]}},
 			GenesisTimeFetcher: &testutil.MockGenesisTimeFetcher{
 				Genesis: time.Now(),
 			},
 			BeaconDB:    db,
-			BlobStorage: bs,
+			BlobStorage: blobStorage,
 		}
-		noBlobIndex := len(blobs) + 1
+
+		noBlobIndex := len(storedBlobSidecars) + 1
 		_, rpcErr := blocker.Blobs(ctx, "123", []int{0, noBlobIndex})
 		require.NotNil(t, rpcErr)
-		assert.Equal(t, core.ErrorReason(core.NotFound), rpcErr.Reason)
+		require.Equal(t, core.ErrorReason(core.NotFound), rpcErr.Reason)
 	})
+
 	t.Run("index too big", func(t *testing.T) {
+		setupDeneb(t)
+
 		blocker := &BeaconDbBlocker{
-			ChainInfoFetcher: &mockChain.ChainService{FinalizedCheckPoint: &ethpb.Checkpoint{Root: blockRoot[:]}},
+			ChainInfoFetcher: &mockChain.ChainService{FinalizedCheckPoint: &ethpb.Checkpoint{Root: denebBlockRoot[:]}},
 			GenesisTimeFetcher: &testutil.MockGenesisTimeFetcher{
 				Genesis: time.Now(),
 			},
 			BeaconDB:    db,
-			BlobStorage: bs,
+			BlobStorage: blobStorage,
 		}
 		_, rpcErr := blocker.Blobs(ctx, "123", []int{0, math.MaxInt})
 		require.NotNil(t, rpcErr)
-		assert.Equal(t, core.ErrorReason(core.BadRequest), rpcErr.Reason)
+		require.Equal(t, core.ErrorReason(core.BadRequest), rpcErr.Reason)
+	})
+
+	t.Run("not enough stored data column sidecars", func(t *testing.T) {
+		setupFulu(t)
+
+		_, dataColumnStorage := filesystem.NewEphemeralDataColumnStorageAndFs(t)
+		err = dataColumnStorage.Save(verifiedRoDataColumnSidecars[:fieldparams.CellsPerBlob-1])
+		require.NoError(t, err)
+
+		blocker := &BeaconDbBlocker{
+			GenesisTimeFetcher: &testutil.MockGenesisTimeFetcher{
+				Genesis: time.Now(),
+			},
+			BeaconDB:          db,
+			BlobStorage:       blobStorage,
+			DataColumnStorage: dataColumnStorage,
+		}
+
+		_, rpcErr := blocker.Blobs(ctx, hexutil.Encode(fuluBlockRoot[:]), nil)
+		require.NotNil(t, rpcErr)
+		require.Equal(t, core.ErrorReason(core.NotFound), rpcErr.Reason)
+	})
+
+	t.Run("reconstruction needed", func(t *testing.T) {
+		setupFulu(t)
+
+		_, dataColumnStorage := filesystem.NewEphemeralDataColumnStorageAndFs(t)
+		err = dataColumnStorage.Save(verifiedRoDataColumnSidecars[1 : peerdas.MinimumColumnsCountToReconstruct()+1])
+		require.NoError(t, err)
+
+		blocker := &BeaconDbBlocker{
+			GenesisTimeFetcher: &testutil.MockGenesisTimeFetcher{
+				Genesis: time.Now(),
+			},
+			BeaconDB:          db,
+			BlobStorage:       blobStorage,
+			DataColumnStorage: dataColumnStorage,
+		}
+
+		retrievedVerifiedRoBlobs, rpcErr := blocker.Blobs(ctx, hexutil.Encode(fuluBlockRoot[:]), nil)
+		require.IsNil(t, rpcErr)
+		require.Equal(t, len(fuluBlobSidecars), len(retrievedVerifiedRoBlobs))
+
+		for i, retrievedVerifiedRoBlob := range retrievedVerifiedRoBlobs {
+			retrievedBlobSidecarPb := retrievedVerifiedRoBlob.BlobSidecar
+			initialBlobSidecarPb := fuluBlobSidecars[i].BlobSidecar
+			require.DeepSSZEqual(t, initialBlobSidecarPb, retrievedBlobSidecarPb)
+		}
+	})
+
+	t.Run("no reconstruction needed", func(t *testing.T) {
+		setupFulu(t)
+
+		_, dataColumnStorage := filesystem.NewEphemeralDataColumnStorageAndFs(t)
+		err = dataColumnStorage.Save(verifiedRoDataColumnSidecars)
+		require.NoError(t, err)
+
+		blocker := &BeaconDbBlocker{
+			GenesisTimeFetcher: &testutil.MockGenesisTimeFetcher{
+				Genesis: time.Now(),
+			},
+			BeaconDB:          db,
+			BlobStorage:       blobStorage,
+			DataColumnStorage: dataColumnStorage,
+		}
+
+		retrievedVerifiedRoBlobs, rpcErr := blocker.Blobs(ctx, hexutil.Encode(fuluBlockRoot[:]), nil)
+		require.IsNil(t, rpcErr)
+		require.Equal(t, len(fuluBlobSidecars), len(retrievedVerifiedRoBlobs))
+
+		for i, retrievedVerifiedRoBlob := range retrievedVerifiedRoBlobs {
+			retrievedBlobSidecarPb := retrievedVerifiedRoBlob.BlobSidecar
+			initialBlobSidecarPb := fuluBlobSidecars[i].BlobSidecar
+			require.DeepSSZEqual(t, initialBlobSidecarPb, retrievedBlobSidecarPb)
+		}
 	})
 }

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

@@ -8,13 +8,18 @@ import (
 	enginev1 "github.com/OffchainLabs/prysm/v6/proto/engine/v1"
 	ethpb "github.com/OffchainLabs/prysm/v6/proto/prysm/v1alpha1"
 	"github.com/OffchainLabs/prysm/v6/runtime/version"
+	"github.com/pkg/errors"
 	"google.golang.org/protobuf/proto"
 )
 
 // constructGenericBeaconBlock constructs a `GenericBeaconBlock` based on the block version and other parameters.
-func (vs *Server) constructGenericBeaconBlock(sBlk interfaces.SignedBeaconBlock, blobsBundle *enginev1.BlobsBundle, winningBid primitives.Wei) (*ethpb.GenericBeaconBlock, error) {
+func (vs *Server) constructGenericBeaconBlock(
+	sBlk interfaces.SignedBeaconBlock,
+	blobsBundler enginev1.BlobsBundler,
+	winningBid primitives.Wei,
+) (*ethpb.GenericBeaconBlock, error) {
 	if sBlk == nil || sBlk.Block() == nil {
-		return nil, fmt.Errorf("block cannot be nil")
+		return nil, errors.New("block cannot be nil")
 	}
 
 	blockProto, err := sBlk.Block().Proto()
@@ -35,11 +40,23 @@ func (vs *Server) constructGenericBeaconBlock(sBlk interfaces.SignedBeaconBlock,
 	case version.Capella:
 		return vs.constructCapellaBlock(blockProto, isBlinded, bidStr), nil
 	case version.Deneb:
-		return vs.constructDenebBlock(blockProto, isBlinded, bidStr, blobsBundle), nil
+		bundle, ok := blobsBundler.(*enginev1.BlobsBundle)
+		if blobsBundler != nil && !ok {
+			return nil, fmt.Errorf("expected *BlobsBundler, got %T", blobsBundler)
+		}
+		return vs.constructDenebBlock(blockProto, isBlinded, bidStr, bundle), nil
 	case version.Electra:
-		return vs.constructElectraBlock(blockProto, isBlinded, bidStr, blobsBundle), nil
+		bundle, ok := blobsBundler.(*enginev1.BlobsBundle)
+		if blobsBundler != nil && !ok {
+			return nil, fmt.Errorf("expected *BlobsBundler, got %T", blobsBundler)
+		}
+		return vs.constructElectraBlock(blockProto, isBlinded, bidStr, bundle), nil
 	case version.Fulu:
-		return vs.constructFuluBlock(blockProto, isBlinded, bidStr, blobsBundle), nil
+		bundle, ok := blobsBundler.(*enginev1.BlobsBundleV2)
+		if blobsBundler != nil && !ok {
+			return nil, fmt.Errorf("expected *BlobsBundleV2, got %T", blobsBundler)
+		}
+		return vs.constructFuluBlock(blockProto, isBlinded, bidStr, bundle), nil
 	default:
 		return nil, fmt.Errorf("unknown block version: %d", sBlk.Version())
 	}
@@ -92,7 +109,7 @@ func (vs *Server) constructElectraBlock(blockProto proto.Message, isBlinded bool
 	return &ethpb.GenericBeaconBlock{Block: &ethpb.GenericBeaconBlock_Electra{Electra: electraContents}, IsBlinded: false, PayloadValue: payloadValue}
 }
 
-func (vs *Server) constructFuluBlock(blockProto proto.Message, isBlinded bool, payloadValue string, bundle *enginev1.BlobsBundle) *ethpb.GenericBeaconBlock {
+func (vs *Server) constructFuluBlock(blockProto proto.Message, isBlinded bool, payloadValue string, bundle *enginev1.BlobsBundleV2) *ethpb.GenericBeaconBlock {
 	if isBlinded {
 		return &ethpb.GenericBeaconBlock{Block: &ethpb.GenericBeaconBlock_BlindedFulu{BlindedFulu: blockProto.(*ethpb.BlindedBeaconBlockFulu)}, IsBlinded: true, PayloadValue: payloadValue}
 	}

beacon-chain/rpc/prysm/v1alpha1/validator/duties_v2.go

@@ -261,6 +261,10 @@ func (vs *Server) buildValidatorDuty(
 }
 
 func populateCommitteeFields(duty *ethpb.DutiesV2Response_Duty, la *helpers.LiteAssignment) {
+	if duty == nil || la == nil {
+		// should never be the case as previous functions should set
+		return
+	}
 	duty.CommitteeLength = la.CommitteeLength
 	duty.CommitteeIndex = la.CommitteeIndex
 	duty.ValidatorCommitteeIndex = la.ValidatorCommitteeIndex

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

@@ -232,7 +232,7 @@ func (vs *Server) BuildBlockParallel(ctx context.Context, sBlk interfaces.Signed
 	}()
 
 	winningBid := primitives.ZeroWei()
-	var bundle *enginev1.BlobsBundle
+	var bundle enginev1.BlobsBundler
 	if sBlk.Version() >= version.Bellatrix {
 		local, err := vs.getLocalPayload(ctx, sBlk.Block(), head)
 		if err != nil {

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

@@ -54,7 +54,7 @@ const blockBuilderTimeout = 1 * time.Second
 const gasLimitAdjustmentFactor = 1024
 
 // Sets the execution data for the block. Execution data can come from local EL client or remote builder depends on validator registration and circuit breaker conditions.
-func setExecutionData(ctx context.Context, blk interfaces.SignedBeaconBlock, local *blocks.GetPayloadResponse, bid builder.Bid, builderBoostFactor primitives.Gwei) (primitives.Wei, *enginev1.BlobsBundle, error) {
+func setExecutionData(ctx context.Context, blk interfaces.SignedBeaconBlock, local *blocks.GetPayloadResponse, bid builder.Bid, builderBoostFactor primitives.Gwei) (primitives.Wei, enginev1.BlobsBundler, error) {
 	_, span := trace.StartSpan(ctx, "ProposerServer.setExecutionData")
 	defer span.End()
 
@@ -69,13 +69,13 @@ func setExecutionData(ctx context.Context, blk interfaces.SignedBeaconBlock, loc
 
 	// Use local payload if builder payload is nil.
 	if bid == nil {
-		return local.Bid, local.BlobsBundle, setLocalExecution(blk, local)
+		return local.Bid, local.BlobsBundler, setLocalExecution(blk, local)
 	}
 
 	builderPayload, err := bid.Header()
 	if err != nil {
 		log.WithError(err).Warn("Proposer: failed to retrieve header from BuilderBid")
-		return local.Bid, local.BlobsBundle, setLocalExecution(blk, local)
+		return local.Bid, local.BlobsBundler, setLocalExecution(blk, local)
 	}
 
 	switch {
@@ -84,7 +84,7 @@ func setExecutionData(ctx context.Context, blk interfaces.SignedBeaconBlock, loc
 		if err != nil {
 			tracing.AnnotateError(span, err)
 			log.WithError(err).Warn("Proposer: failed to match withdrawals root")
-			return local.Bid, local.BlobsBundle, setLocalExecution(blk, local)
+			return local.Bid, local.BlobsBundler, setLocalExecution(blk, local)
 		}
 
 		// Compare payload values between local and builder. Default to the local value if it is higher.
@@ -97,7 +97,7 @@ func setExecutionData(ctx context.Context, blk interfaces.SignedBeaconBlock, loc
 				"minBuilderBid":    minBid,
 				"builderGweiValue": builderValueGwei,
 			}).Warn("Proposer: using local execution payload because min bid not attained")
-			return local.Bid, local.BlobsBundle, setLocalExecution(blk, local)
+			return local.Bid, local.BlobsBundler, setLocalExecution(blk, local)
 		}
 
 		// Use local block if min difference is not attained
@@ -108,7 +108,7 @@ func setExecutionData(ctx context.Context, blk interfaces.SignedBeaconBlock, loc
 				"minBidDiff":       minDiff,
 				"builderGweiValue": builderValueGwei,
 			}).Warn("Proposer: using local execution payload because min difference with local value was not attained")
-			return local.Bid, local.BlobsBundle, setLocalExecution(blk, local)
+			return local.Bid, local.BlobsBundler, setLocalExecution(blk, local)
 		}
 
 		// Use builder payload if the following in true:
@@ -133,7 +133,7 @@ func setExecutionData(ctx context.Context, blk interfaces.SignedBeaconBlock, loc
 				bidDeneb, ok := bid.(builder.BidDeneb)
 				if !ok {
 					log.Warnf("bid type %T does not implement builder.BidDeneb", bid)
-					return local.Bid, local.BlobsBundle, setLocalExecution(blk, local)
+					return local.Bid, local.BlobsBundler, setLocalExecution(blk, local)
 				} else {
 					builderKzgCommitments = bidDeneb.BlobKzgCommitments()
 				}
@@ -144,14 +144,14 @@ func setExecutionData(ctx context.Context, blk interfaces.SignedBeaconBlock, loc
 				bidElectra, ok := bid.(builder.BidElectra)
 				if !ok {
 					log.Warnf("bid type %T does not implement builder.BidElectra", bid)
-					return local.Bid, local.BlobsBundle, setLocalExecution(blk, local)
+					return local.Bid, local.BlobsBundler, setLocalExecution(blk, local)
 				} else {
 					executionRequests = bidElectra.ExecutionRequests()
 				}
 			}
 			if err := setBuilderExecution(blk, builderPayload, builderKzgCommitments, executionRequests); err != nil {
 				log.WithError(err).Warn("Proposer: failed to set builder payload")
-				return local.Bid, local.BlobsBundle, setLocalExecution(blk, local)
+				return local.Bid, local.BlobsBundler, setLocalExecution(blk, local)
 			} else {
 				return bid.Value(), nil, nil
 			}
@@ -171,11 +171,11 @@ func setExecutionData(ctx context.Context, blk interfaces.SignedBeaconBlock, loc
 			trace.Int64Attribute("builderGweiValue", int64(builderValueGwei)),     // lint:ignore uintcast -- This is OK for tracing.
 			trace.Int64Attribute("builderBoostFactor", int64(builderBoostFactor)), // lint:ignore uintcast -- This is OK for tracing.
 		)
-		return local.Bid, local.BlobsBundle, setLocalExecution(blk, local)
+		return local.Bid, local.BlobsBundler, setLocalExecution(blk, local)
 	default: // Bellatrix case.
 		if err := setBuilderExecution(blk, builderPayload, nil, nil); err != nil {
 			log.WithError(err).Warn("Proposer: failed to set builder payload")
-			return local.Bid, local.BlobsBundle, setLocalExecution(blk, local)
+			return local.Bid, local.BlobsBundler, setLocalExecution(blk, local)
 		} else {
 			return bid.Value(), nil, nil
 		}
@@ -375,8 +375,8 @@ func matchingWithdrawalsRoot(local, builder interfaces.ExecutionData) (bool, err
 // It delegates to setExecution for the actual work.
 func setLocalExecution(blk interfaces.SignedBeaconBlock, local *blocks.GetPayloadResponse) error {
 	var kzgCommitments [][]byte
-	if local.BlobsBundle != nil {
-		kzgCommitments = local.BlobsBundle.KzgCommitments
+	if local.BlobsBundler != nil {
+		kzgCommitments = local.BlobsBundler.GetKzgCommitments()
 	}
 	if local.ExecutionRequests != nil {
 		if err := blk.SetExecutionRequests(local.ExecutionRequests); err != nil {

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

@@ -519,7 +519,7 @@ func TestServer_setExecutionData(t *testing.T) {
 			PayloadIDBytes: id,
 			GetPayloadResponse: &blocks.GetPayloadResponse{
 				ExecutionData: ed,
-				BlobsBundle:   blobsBundle,
+				BlobsBundler:  blobsBundle,
 				Bid:           primitives.ZeroWei(),
 			},
 		}
@@ -527,7 +527,7 @@ func TestServer_setExecutionData(t *testing.T) {
 		res, err := vs.getLocalPayload(ctx, blk.Block(), capellaTransitionState)
 		require.NoError(t, err)
 		require.Equal(t, uint64(4), res.ExecutionData.BlockNumber())
-		require.DeepEqual(t, res.BlobsBundle, blobsBundle)
+		require.DeepEqual(t, res.BlobsBundler, blobsBundle)
 	})
 	t.Run("Can get builder payload and blobs in Deneb", func(t *testing.T) {
 		cfg := params.BeaconConfig().Copy()

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

@@ -529,7 +529,7 @@ func TestServer_GetBeaconBlock_Deneb(t *testing.T) {
 		PayloadIDBytes: &enginev1.PayloadIDBytes{1},
 		GetPayloadResponse: &blocks.GetPayloadResponse{
 			ExecutionData: ed,
-			BlobsBundle:   bundle,
+			BlobsBundler:  bundle,
 		},
 	}
 

beacon-chain/sync/BUILD.bazel

@@ -7,6 +7,7 @@ go_library(
         "block_batcher.go",
         "broadcast_bls_changes.go",
         "context.go",
+        "data_columns_reconstruct.go",
         "deadlines.go",
         "decode_pubsub.go",
         "doc.go",
@@ -25,6 +26,7 @@ go_library(
         "rpc_blob_sidecars_by_range.go",
         "rpc_blob_sidecars_by_root.go",
         "rpc_chunked_response.go",
+        "rpc_data_column_sidecars_by_range.go",
         "rpc_data_column_sidecars_by_root.go",
         "rpc_goodbye.go",
         "rpc_light_client.go",
@@ -39,6 +41,7 @@ go_library(
         "subscriber_beacon_blocks.go",
         "subscriber_blob_sidecar.go",
         "subscriber_bls_to_execution_change.go",
+        "subscriber_data_column_sidecar.go",
         "subscriber_handlers.go",
         "subscriber_light_client.go",
         "subscriber_sync_committee_message.go",
@@ -77,6 +80,7 @@ go_library(
         "//beacon-chain/core/feed/state: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/core/transition:go_default_library",
         "//beacon-chain/core/transition/interop:go_default_library",
@@ -161,6 +165,7 @@ go_test(
         "block_batcher_test.go",
         "broadcast_bls_changes_test.go",
         "context_test.go",
+        "data_columns_reconstruct_test.go",
         "decode_pubsub_test.go",
         "error_test.go",
         "fork_watcher_test.go",
@@ -171,6 +176,7 @@ go_test(
         "rpc_beacon_blocks_by_root_test.go",
         "rpc_blob_sidecars_by_range_test.go",
         "rpc_blob_sidecars_by_root_test.go",
+        "rpc_data_column_sidecars_by_range_test.go",
         "rpc_data_column_sidecars_by_root_test.go",
         "rpc_goodbye_test.go",
         "rpc_handler_test.go",
@@ -205,6 +211,7 @@ go_test(
     deps = [
         "//async/abool:go_default_library",
         "//beacon-chain/blockchain:go_default_library",
+        "//beacon-chain/blockchain/kzg:go_default_library",
         "//beacon-chain/blockchain/testing:go_default_library",
         "//beacon-chain/cache:go_default_library",
         "//beacon-chain/core/altair:go_default_library",
@@ -212,6 +219,7 @@ go_test(
         "//beacon-chain/core/feed/operation: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/core/time:go_default_library",
         "//beacon-chain/core/transition:go_default_library",
@@ -282,6 +290,7 @@ go_test(
         "@com_github_prysmaticlabs_go_bitfield//:go_default_library",
         "@com_github_sirupsen_logrus//:go_default_library",
         "@com_github_sirupsen_logrus//hooks/test:go_default_library",
+        "@com_github_stretchr_testify//require:go_default_library",
         "@org_golang_google_protobuf//proto:go_default_library",
     ],
 )

beacon-chain/sync/batch_verifier.go

@@ -13,8 +13,6 @@ import (
 
 const signatureVerificationInterval = 50 * time.Millisecond
 
-const verifierLimit = 50
-
 type signatureVerifier struct {
 	set     *bls.SignatureBatch
 	resChan chan error
@@ -36,7 +34,7 @@ func (s *Service) verifierRoutine() {
 			return
 		case sig := <-s.signatureChan:
 			verifierBatch = append(verifierBatch, sig)
-			if len(verifierBatch) >= verifierLimit {
+			if len(verifierBatch) >= s.cfg.batchVerifierLimit {
 				verifyBatch(verifierBatch)
 				verifierBatch = []*signatureVerifier{}
 			}

beacon-chain/sync/batch_verifier_test.go

@@ -67,6 +67,7 @@ func TestValidateWithBatchVerifier(t *testing.T) {
 			ctx, cancel := context.WithCancel(t.Context())
 			svc := &Service{
 				ctx:           ctx,
+				cfg:           &config{batchVerifierLimit: verifierLimit},
 				cancel:        cancel,
 				signatureChan: make(chan *signatureVerifier, verifierLimit),
 			}

beacon-chain/sync/data_columns_reconstruct.go

@@ -0,0 +1,208 @@
+package sync
+
+import (
+	"context"
+	"fmt"
+	"slices"
+	"time"
+
+	"github.com/OffchainLabs/prysm/v6/beacon-chain/core/peerdas"
+	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/primitives"
+	"github.com/OffchainLabs/prysm/v6/time/slots"
+	"github.com/pkg/errors"
+	"github.com/sirupsen/logrus"
+)
+
+const (
+	broadcastMissingDataColumnsTimeIntoSlotMin = 1 * time.Second
+	broadcastMissingDataColumnsSlack           = 2 * time.Second
+)
+
+// reconstructSaveBroadcastDataColumnSidecars reconstructs if possible and
+// needed all data column sidecars. Then, it saves into the store missing
+// sidecars. After a delay, it broadcasts in the background not seen via gossip
+// (but reconstructed) sidecars.
+func (s *Service) reconstructSaveBroadcastDataColumnSidecars(
+	ctx context.Context,
+	slot primitives.Slot,
+	proposerIndex primitives.ValidatorIndex,
+	root [fieldparams.RootLength]byte,
+) error {
+	startTime := time.Now()
+
+	// Get the columns we store.
+	storedDataColumns := s.cfg.dataColumnStorage.Summary(root)
+	storedColumnsCount := storedDataColumns.Count()
+	numberOfColumns := params.BeaconConfig().NumberOfColumns
+
+	// Lock to prevent concurrent reconstructions.
+	s.reconstructionLock.Lock()
+	defer s.reconstructionLock.Unlock()
+
+	// If reconstruction is not possible or if all columns are already stored, exit early.
+	if storedColumnsCount < peerdas.MinimumColumnsCountToReconstruct() || storedColumnsCount == numberOfColumns {
+		return nil
+	}
+
+	// Retrieve our local node info.
+	nodeID := s.cfg.p2p.NodeID()
+	custodyGroupCount := s.cfg.custodyInfo.ActualGroupCount()
+	localNodeInfo, _, err := peerdas.Info(nodeID, custodyGroupCount)
+	if err != nil {
+		return errors.Wrap(err, "peer info")
+	}
+
+	// Load all the possible data columns sidecars, to minimize reconstruction time.
+	verifiedSidecars, err := s.cfg.dataColumnStorage.Get(root, nil)
+	if err != nil {
+		return errors.Wrap(err, "get data column sidecars")
+	}
+
+	// Reconstruct all the data column sidecars.
+	reconstructedSidecars, err := peerdas.ReconstructDataColumnSidecars(verifiedSidecars)
+	if err != nil {
+		return errors.Wrap(err, "reconstruct data column sidecars")
+	}
+
+	// Filter reconstructed sidecars to save.
+	custodyColumns := localNodeInfo.CustodyColumns
+	toSaveSidecars := make([]blocks.VerifiedRODataColumn, 0, len(custodyColumns))
+	for _, sidecar := range reconstructedSidecars {
+		if custodyColumns[sidecar.Index] {
+			toSaveSidecars = append(toSaveSidecars, sidecar)
+		}
+	}
+
+	// Save the data columns sidecars in the database.
+	// Note: We do not call `receiveDataColumn`, because it will ignore
+	// incoming data columns via gossip while we did not broadcast (yet) the reconstructed data columns.
+	if err := s.cfg.dataColumnStorage.Save(toSaveSidecars); err != nil {
+		return errors.Wrap(err, "save data column sidecars")
+	}
+
+	// Update reconstruction metrics
+	dataColumnReconstructionHistogram.Observe(float64(time.Since(startTime).Milliseconds()))
+	dataColumnReconstructionCounter.Add(float64(len(reconstructedSidecars) - len(verifiedSidecars)))
+
+	// Schedule the broadcast.
+	if err := s.scheduleMissingDataColumnSidecarsBroadcast(ctx, root, proposerIndex, slot); err != nil {
+		return errors.Wrap(err, "schedule reconstructed data columns broadcast")
+	}
+
+	log.WithFields(logrus.Fields{
+		"root":             fmt.Sprintf("%#x", root),
+		"slot":             slot,
+		"fromColumnsCount": storedColumnsCount,
+	}).Debug("Data columns reconstructed and saved")
+
+	return nil
+}
+
+// scheduleMissingDataColumnSidecarsBroadcast schedules the broadcast of missing
+// (aka. not seen via gossip but reconstructed) sidecars.
+func (s *Service) scheduleMissingDataColumnSidecarsBroadcast(
+	ctx context.Context,
+	root [fieldparams.RootLength]byte,
+	proposerIndex primitives.ValidatorIndex,
+	slot primitives.Slot,
+) error {
+	log := log.WithFields(logrus.Fields{
+		"root": fmt.Sprintf("%x", root),
+		"slot": slot,
+	})
+
+	// Get the time corresponding to the start of the slot.
+	genesisTime := uint64(s.cfg.chain.GenesisTime().Unix())
+	slotStartTime, err := slots.ToTime(genesisTime, slot)
+	if err != nil {
+		return errors.Wrap(err, "to time")
+	}
+
+	// Compute the waiting time. This could be negative. In such a case, broadcast immediately.
+	randFloat := s.reconstructionRandGen.Float64()
+	timeIntoSlot := broadcastMissingDataColumnsTimeIntoSlotMin + time.Duration(float64(broadcastMissingDataColumnsSlack)*randFloat)
+	broadcastTime := slotStartTime.Add(timeIntoSlot)
+	waitingTime := time.Until(broadcastTime)
+	time.AfterFunc(waitingTime, func() {
+		// Return early if the context was canceled during the waiting time.
+		if err := ctx.Err(); err != nil {
+			return
+		}
+
+		if err := s.broadcastMissingDataColumnSidecars(slot, proposerIndex, root, timeIntoSlot); err != nil {
+			log.WithError(err).Error("Failed to broadcast missing data column sidecars")
+		}
+	})
+
+	return nil
+}
+
+func (s *Service) broadcastMissingDataColumnSidecars(
+	slot primitives.Slot,
+	proposerIndex primitives.ValidatorIndex,
+	root [fieldparams.RootLength]byte,
+	timeIntoSlot time.Duration,
+) error {
+	// Get the node ID.
+	nodeID := s.cfg.p2p.NodeID()
+
+	// Get the custody group count.
+	custodyGroupCount := s.cfg.custodyInfo.ActualGroupCount()
+
+	// Retrieve the local node info.
+	localNodeInfo, _, err := peerdas.Info(nodeID, custodyGroupCount)
+	if err != nil {
+		return errors.Wrap(err, "peerdas info")
+	}
+
+	// Compute the missing data columns (data columns we should custody but we did not received via gossip.)
+	missingColumns := make([]uint64, 0, len(localNodeInfo.CustodyColumns))
+	for column := range localNodeInfo.CustodyColumns {
+		if !s.hasSeenDataColumnIndex(slot, proposerIndex, column) {
+			missingColumns = append(missingColumns, column)
+		}
+	}
+
+	// Return early if there are no missing data columns.
+	if len(missingColumns) == 0 {
+		return nil
+	}
+
+	// Load from the store the non received but reconstructed data column.
+	verifiedRODataColumnSidecars, err := s.cfg.dataColumnStorage.Get(root, missingColumns)
+	if err != nil {
+		return errors.Wrap(err, "data column storage get")
+	}
+
+	broadcastedColumns := make([]uint64, 0, len(verifiedRODataColumnSidecars))
+	for _, verifiedRODataColumn := range verifiedRODataColumnSidecars {
+		broadcastedColumns = append(broadcastedColumns, verifiedRODataColumn.Index)
+		// Compute the subnet for this column.
+		subnet := peerdas.ComputeSubnetForDataColumnSidecar(verifiedRODataColumn.Index)
+
+		// Broadcast the missing data column.
+		if err := s.cfg.p2p.BroadcastDataColumn(root, subnet, verifiedRODataColumn.DataColumnSidecar); err != nil {
+			log.WithError(err).Error("Broadcast data column")
+		}
+
+		// Now, we can set the data column as seen.
+		s.setSeenDataColumnIndex(slot, proposerIndex, verifiedRODataColumn.Index)
+	}
+
+	if logrus.GetLevel() >= logrus.DebugLevel {
+		// Sort for nice logging.
+		slices.Sort(broadcastedColumns)
+		slices.Sort(missingColumns)
+
+		log.WithFields(logrus.Fields{
+			"timeIntoSlot":   timeIntoSlot,
+			"missingColumns": missingColumns,
+			"broadcasted":    broadcastedColumns,
+		}).Debug("Start broadcasting not seen via gossip but reconstructed data columns")
+	}
+
+	return nil
+}

beacon-chain/sync/data_columns_reconstruct_test.go

@@ -0,0 +1,191 @@
+package sync
+
+import (
+	"testing"
+
+	"github.com/OffchainLabs/prysm/v6/beacon-chain/blockchain/kzg"
+	mockChain "github.com/OffchainLabs/prysm/v6/beacon-chain/blockchain/testing"
+	"github.com/OffchainLabs/prysm/v6/beacon-chain/core/peerdas"
+	"github.com/OffchainLabs/prysm/v6/beacon-chain/db/filesystem"
+	p2ptest "github.com/OffchainLabs/prysm/v6/beacon-chain/p2p/testing"
+	"github.com/OffchainLabs/prysm/v6/config/params"
+	"github.com/OffchainLabs/prysm/v6/consensus-types/blocks"
+	"github.com/OffchainLabs/prysm/v6/testing/require"
+	"github.com/OffchainLabs/prysm/v6/testing/util"
+)
+
+func TestReconstructDataColumns(t *testing.T) {
+	const blobCount = 4
+	numberOfColumns := params.BeaconConfig().NumberOfColumns
+
+	ctx := t.Context()
+
+	// Start the trusted setup.
+	err := kzg.Start()
+	require.NoError(t, err)
+
+	roBlock, _, verifiedRoDataColumns := util.GenerateTestFuluBlockWithSidecars(t, blobCount)
+	require.Equal(t, numberOfColumns, uint64(len(verifiedRoDataColumns)))
+
+	root, block := roBlock.Root(), roBlock.Block()
+	slot, proposerIndex := block.Slot(), block.ProposerIndex()
+
+	minimumCount := peerdas.MinimumColumnsCountToReconstruct()
+
+	t.Run("not enough stored sidecars", func(t *testing.T) {
+		storage := filesystem.NewEphemeralDataColumnStorage(t)
+		err := storage.Save(verifiedRoDataColumns[:minimumCount-1])
+		require.NoError(t, err)
+
+		service := NewService(ctx, WithP2P(p2ptest.NewTestP2P(t)), WithDataColumnStorage(storage))
+		err = service.reconstructSaveBroadcastDataColumnSidecars(ctx, slot, proposerIndex, root)
+		require.NoError(t, err)
+	})
+
+	t.Run("all stored sidecars", func(t *testing.T) {
+		storage := filesystem.NewEphemeralDataColumnStorage(t)
+		err := storage.Save(verifiedRoDataColumns)
+		require.NoError(t, err)
+
+		service := NewService(ctx, WithP2P(p2ptest.NewTestP2P(t)), WithDataColumnStorage(storage))
+		err = service.reconstructSaveBroadcastDataColumnSidecars(ctx, slot, proposerIndex, root)
+		require.NoError(t, err)
+	})
+
+	t.Run("should reconstruct", func(t *testing.T) {
+		// Here we setup a cgc of 8, which is not realistic, since there is no
+		// real reason for a node to both:
+		// - store enough data column sidecars to enable reconstruction, and
+		// - custody not enough columns to enable reconstruction.
+		// However, for the needs of this test, this is perfectly fine.
+		const cgc = 8
+
+		storage := filesystem.NewEphemeralDataColumnStorage(t)
+		minimumCount := peerdas.MinimumColumnsCountToReconstruct()
+		err := storage.Save(verifiedRoDataColumns[:minimumCount])
+		require.NoError(t, err)
+
+		custodyInfo := &peerdas.CustodyInfo{}
+		custodyInfo.TargetGroupCount.SetValidatorsCustodyRequirement(cgc)
+		custodyInfo.ToAdvertiseGroupCount.Set(cgc)
+
+		service := NewService(
+			ctx,
+			WithP2P(p2ptest.NewTestP2P(t)),
+			WithDataColumnStorage(storage),
+			WithCustodyInfo(custodyInfo),
+			WithChainService(&mockChain.ChainService{}),
+		)
+
+		err = service.reconstructSaveBroadcastDataColumnSidecars(ctx, slot, proposerIndex, root)
+		require.NoError(t, err)
+
+		expected := make(map[uint64]bool, minimumCount+cgc)
+		for i := range minimumCount {
+			expected[i] = true
+		}
+
+		// The node should custody these indices.
+		for _, i := range [...]uint64{1, 17, 19, 42, 75, 87, 102, 117} {
+			expected[i] = true
+		}
+
+		summary := storage.Summary(root)
+		actual := summary.Stored()
+
+		require.Equal(t, len(expected), len(actual))
+		for index := range expected {
+			require.Equal(t, true, actual[index])
+		}
+	})
+}
+
+func TestBroadcastMissingDataColumnSidecars(t *testing.T) {
+	const (
+		cgc          = 8
+		blobCount    = 4
+		timeIntoSlot = 0
+	)
+
+	numberOfColumns := params.BeaconConfig().NumberOfColumns
+	ctx := t.Context()
+
+	// Start the trusted setup.
+	err := kzg.Start()
+	require.NoError(t, err)
+
+	roBlock, _, verifiedRoDataColumns := util.GenerateTestFuluBlockWithSidecars(t, blobCount)
+	require.Equal(t, numberOfColumns, uint64(len(verifiedRoDataColumns)))
+
+	root, block := roBlock.Root(), roBlock.Block()
+	slot, proposerIndex := block.Slot(), block.ProposerIndex()
+
+	t.Run("no missing sidecars", func(t *testing.T) {
+		custodyInfo := &peerdas.CustodyInfo{}
+		custodyInfo.TargetGroupCount.SetValidatorsCustodyRequirement(cgc)
+		custodyInfo.ToAdvertiseGroupCount.Set(cgc)
+
+		service := NewService(
+			ctx,
+			WithP2P(p2ptest.NewTestP2P(t)),
+			WithCustodyInfo(custodyInfo),
+		)
+
+		for _, index := range [...]uint64{1, 17, 19, 42, 75, 87, 102, 117} {
+			key := computeCacheKey(slot, proposerIndex, index)
+			service.seenDataColumnCache.Add(key, true)
+		}
+
+		err := service.broadcastMissingDataColumnSidecars(slot, proposerIndex, root, timeIntoSlot)
+		require.NoError(t, err)
+	})
+
+	t.Run("some missing sidecars", func(t *testing.T) {
+		custodyInfo := &peerdas.CustodyInfo{}
+		custodyInfo.TargetGroupCount.SetValidatorsCustodyRequirement(cgc)
+		custodyInfo.ToAdvertiseGroupCount.Set(cgc)
+
+		toSave := make([]blocks.VerifiedRODataColumn, 0, 2)
+		for _, index := range [...]uint64{42, 87} {
+			toSave = append(toSave, verifiedRoDataColumns[index])
+		}
+
+		p2p := p2ptest.NewTestP2P(t)
+		storage := filesystem.NewEphemeralDataColumnStorage(t)
+		err := storage.Save(toSave)
+		require.NoError(t, err)
+
+		service := NewService(
+			ctx,
+			WithP2P(p2p),
+			WithCustodyInfo(custodyInfo),
+			WithDataColumnStorage(storage),
+		)
+
+		for _, index := range [...]uint64{1, 17, 19, 102, 117} { // 42, 75 and 87 are missing
+			key := computeCacheKey(slot, proposerIndex, index)
+			service.seenDataColumnCache.Add(key, true)
+		}
+
+		for _, index := range [...]uint64{42, 75, 87} {
+			seen := service.hasSeenDataColumnIndex(slot, proposerIndex, index)
+			require.Equal(t, false, seen)
+		}
+
+		require.Equal(t, false, p2p.BroadcastCalled.Load())
+
+		err = service.broadcastMissingDataColumnSidecars(slot, proposerIndex, root, timeIntoSlot)
+		require.NoError(t, err)
+
+		seen := service.hasSeenDataColumnIndex(slot, proposerIndex, 75)
+		require.Equal(t, false, seen)
+
+		for _, index := range [...]uint64{42, 87} {
+			seen := service.hasSeenDataColumnIndex(slot, proposerIndex, index)
+			require.Equal(t, true, seen)
+		}
+
+		require.Equal(t, true, p2p.BroadcastCalled.Load())
+
+	})
+}

beacon-chain/sync/fork_watcher_test.go

@@ -7,6 +7,7 @@ import (
 
 	"github.com/OffchainLabs/prysm/v6/async/abool"
 	mockChain "github.com/OffchainLabs/prysm/v6/beacon-chain/blockchain/testing"
+	"github.com/OffchainLabs/prysm/v6/beacon-chain/core/peerdas"
 	"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"
@@ -46,6 +47,7 @@ func TestService_CheckForNextEpochFork(t *testing.T) {
 						chain:       chainService,
 						clock:       startup.NewClock(gt, vr),
 						initialSync: &mockSync.Sync{IsSyncing: false},
+						custodyInfo: &peerdas.CustodyInfo{},
 					},
 					chainStarted: abool.New(),
 					subHandler:   newSubTopicHandler(),
@@ -81,6 +83,7 @@ func TestService_CheckForNextEpochFork(t *testing.T) {
 						chain:       chainService,
 						clock:       startup.NewClock(gt, vr),
 						initialSync: &mockSync.Sync{IsSyncing: false},
+						custodyInfo: &peerdas.CustodyInfo{},
 					},
 					chainStarted: abool.New(),
 					subHandler:   newSubTopicHandler(),
@@ -125,6 +128,7 @@ func TestService_CheckForNextEpochFork(t *testing.T) {
 						chain:       chainService,
 						clock:       startup.NewClock(chainService.Genesis, chainService.ValidatorsRoot),
 						initialSync: &mockSync.Sync{IsSyncing: false},
+						custodyInfo: &peerdas.CustodyInfo{},
 					},
 					chainStarted: abool.New(),
 					subHandler:   newSubTopicHandler(),
@@ -167,6 +171,7 @@ func TestService_CheckForNextEpochFork(t *testing.T) {
 						chain:       chainService,
 						clock:       startup.NewClock(gt, vr),
 						initialSync: &mockSync.Sync{IsSyncing: false},
+						custodyInfo: &peerdas.CustodyInfo{},
 					},
 					chainStarted: abool.New(),
 					subHandler:   newSubTopicHandler(),
@@ -211,6 +216,7 @@ func TestService_CheckForNextEpochFork(t *testing.T) {
 						chain:       chainService,
 						clock:       startup.NewClock(gt, vr),
 						initialSync: &mockSync.Sync{IsSyncing: false},
+						custodyInfo: &peerdas.CustodyInfo{},
 					},
 					chainStarted: abool.New(),
 					subHandler:   newSubTopicHandler(),
@@ -255,6 +261,7 @@ func TestService_CheckForNextEpochFork(t *testing.T) {
 						chain:       chainService,
 						clock:       startup.NewClock(gt, vr),
 						initialSync: &mockSync.Sync{IsSyncing: false},
+						custodyInfo: &peerdas.CustodyInfo{},
 					},
 					chainStarted: abool.New(),
 					subHandler:   newSubTopicHandler(),
@@ -274,6 +281,7 @@ func TestService_CheckForNextEpochFork(t *testing.T) {
 				}
 				assert.Equal(t, true, rpcMap[p2p.RPCBlobSidecarsByRangeTopicV1+s.cfg.p2p.Encoding().ProtocolSuffix()], "topic doesn't exist")
 				assert.Equal(t, true, rpcMap[p2p.RPCBlobSidecarsByRootTopicV1+s.cfg.p2p.Encoding().ProtocolSuffix()], "topic doesn't exist")
+				assert.Equal(t, true, rpcMap[p2p.RPCMetaDataTopicV3+s.cfg.p2p.Encoding().ProtocolSuffix()], "topic doesn't exist")
 			},
 		},
 	}

beacon-chain/sync/metrics.go

@@ -89,6 +89,13 @@ var (
 			Buckets: []float64{5, 10, 50, 100, 150, 250, 500, 1000, 2000},
 		},
 	)
+	rpcDataColumnsByRangeResponseLatency = promauto.NewHistogram(
+		prometheus.HistogramOpts{
+			Name:    "rpc_data_columns_by_range_response_latency_milliseconds",
+			Help:    "Captures total time to respond to rpc DataColumnsByRange requests in a milliseconds distribution",
+			Buckets: []float64{5, 10, 50, 100, 150, 250, 500, 1000, 2000},
+		},
+	)
 	arrivalBlockPropagationHistogram = promauto.NewHistogram(
 		prometheus.HistogramOpts{
 			Name:    "block_arrival_latency_milliseconds",
@@ -203,6 +210,19 @@ var (
 			Buckets: []float64{100, 250, 500, 750, 1000, 1500, 2000, 4000, 8000, 12000, 16000},
 		},
 	)
+
+	dataColumnReconstructionCounter = promauto.NewCounter(prometheus.CounterOpts{
+		Name: "beacon_data_availability_reconstructed_columns_total",
+		Help: "Count the number of reconstructed data columns.",
+	})
+
+	dataColumnReconstructionHistogram = promauto.NewHistogram(
+		prometheus.HistogramOpts{
+			Name:    "beacon_data_availability_reconstruction_time_milliseconds",
+			Help:    "Captures the time taken to reconstruct data columns.",
+			Buckets: []float64{100, 250, 500, 750, 1000, 1500, 2000, 4000, 8000, 12000, 16000},
+		},
+	)
 )
 
 func (s *Service) updateMetrics() {

beacon-chain/sync/options.go

@@ -7,6 +7,7 @@ import (
 	"github.com/OffchainLabs/prysm/v6/beacon-chain/core/feed/operation"
 	statefeed "github.com/OffchainLabs/prysm/v6/beacon-chain/core/feed/state"
 	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/db"
 	"github.com/OffchainLabs/prysm/v6/beacon-chain/db/filesystem"
 	"github.com/OffchainLabs/prysm/v6/beacon-chain/execution"
@@ -198,6 +199,14 @@ func WithAvailableBlocker(avb coverage.AvailableBlocker) Option {
 	}
 }
 
+// WithCustodyInfo for custody info.
+func WithCustodyInfo(custodyInfo *peerdas.CustodyInfo) Option {
+	return func(s *Service) error {
+		s.cfg.custodyInfo = custodyInfo
+		return nil
+	}
+}
+
 // WithSlasherEnabled configures the sync package to support slashing detection.
 func WithSlasherEnabled(enabled bool) Option {
 	return func(s *Service) error {
@@ -213,3 +222,11 @@ func WithLightClientStore(lcs *lightClient.Store) Option {
 		return nil
 	}
 }
+
+// WithBatchVerifierLimit sets the maximum number of signatures to batch verify at once.
+func WithBatchVerifierLimit(limit int) Option {
+	return func(s *Service) error {
+		s.cfg.batchVerifierLimit = limit
+		return nil
+	}
+}

beacon-chain/sync/pending_attestations_queue_test.go

@@ -40,6 +40,8 @@ import (
 	logTest "github.com/sirupsen/logrus/hooks/test"
 )
 
+var verifierLimit = 1000
+
 func TestProcessPendingAtts_NoBlockRequestBlock(t *testing.T) {
 	hook := logTest.NewGlobal()
 	db := dbtest.SetupDB(t)

beacon-chain/sync/rate_limiter.go

@@ -47,13 +47,18 @@ func newRateLimiter(p2pProvider p2p.P2P) *limiter {
 	allowedBlobsPerSecond := float64(flags.Get().BlobBatchLimit)
 	allowedBlobsBurst := int64(flags.Get().BlobBatchLimitBurstFactor * flags.Get().BlobBatchLimit)
 
+	// Initialize data column limits.
+	allowedDataColumnsPerSecond := float64(flags.Get().DataColumnBatchLimit)
+	allowedDataColumnsBurst := int64(flags.Get().DataColumnBatchLimitBurstFactor * flags.Get().DataColumnBatchLimit)
+
 	// Set topic map for all rpc topics.
 	topicMap := make(map[string]*leakybucket.Collector, len(p2p.RPCTopicMappings))
 	// Goodbye Message
 	topicMap[addEncoding(p2p.RPCGoodByeTopicV1)] = leakybucket.NewCollector(1, 1, leakyBucketPeriod, false /* deleteEmptyBuckets */)
-	// MetadataV0 Message
+	// Metadata Message
 	topicMap[addEncoding(p2p.RPCMetaDataTopicV1)] = leakybucket.NewCollector(1, defaultBurstLimit, leakyBucketPeriod, false /* deleteEmptyBuckets */)
 	topicMap[addEncoding(p2p.RPCMetaDataTopicV2)] = leakybucket.NewCollector(1, defaultBurstLimit, leakyBucketPeriod, false /* deleteEmptyBuckets */)
+	topicMap[addEncoding(p2p.RPCMetaDataTopicV3)] = leakybucket.NewCollector(1, defaultBurstLimit, leakyBucketPeriod, false /* deleteEmptyBuckets */)
 	// Ping Message
 	topicMap[addEncoding(p2p.RPCPingTopicV1)] = leakybucket.NewCollector(1, defaultBurstLimit, leakyBucketPeriod, false /* deleteEmptyBuckets */)
 	// Status Message
@@ -67,6 +72,9 @@ func newRateLimiter(p2pProvider p2p.P2P) *limiter {
 	// for BlobSidecarsByRoot and BlobSidecarsByRange
 	blobCollector := leakybucket.NewCollector(allowedBlobsPerSecond, allowedBlobsBurst, blockBucketPeriod, false)
 
+	// for DataColumnSidecarsByRoot and DataColumnSidecarsByRange
+	dataColumnSidecars := leakybucket.NewCollector(allowedDataColumnsPerSecond, allowedDataColumnsBurst, blockBucketPeriod, false)
+
 	// BlocksByRoots requests
 	topicMap[addEncoding(p2p.RPCBlocksByRootTopicV1)] = blockCollector
 	topicMap[addEncoding(p2p.RPCBlocksByRootTopicV2)] = blockCollectorV2
@@ -86,6 +94,11 @@ func newRateLimiter(p2pProvider p2p.P2P) *limiter {
 	topicMap[addEncoding(p2p.RPCLightClientOptimisticUpdateTopicV1)] = leakybucket.NewCollector(1, defaultBurstLimit, leakyBucketPeriod, false /* deleteEmptyBuckets */)
 	topicMap[addEncoding(p2p.RPCLightClientFinalityUpdateTopicV1)] = leakybucket.NewCollector(1, defaultBurstLimit, leakyBucketPeriod, false /* deleteEmptyBuckets */)
 
+	// DataColumnSidecarsByRootV1
+	topicMap[addEncoding(p2p.RPCDataColumnSidecarsByRootTopicV1)] = dataColumnSidecars
+	// DataColumnSidecarsByRangeV1
+	topicMap[addEncoding(p2p.RPCDataColumnSidecarsByRangeTopicV1)] = dataColumnSidecars
+
 	// General topic for all rpc requests.
 	topicMap[rpcLimiterTopic] = leakybucket.NewCollector(5, defaultBurstLimit*2, leakyBucketPeriod, false /* deleteEmptyBuckets */)
 

beacon-chain/sync/rate_limiter_test.go

@@ -17,7 +17,7 @@ import (
 
 func TestNewRateLimiter(t *testing.T) {
 	rlimiter := newRateLimiter(mockp2p.NewTestP2P(t))
-	assert.Equal(t, len(rlimiter.limiterMap), 16, "correct number of topics not registered")
+	assert.Equal(t, len(rlimiter.limiterMap), 19, "correct number of topics not registered")
 }
 
 func TestNewRateLimiter_FreeCorrectly(t *testing.T) {

beacon-chain/sync/rpc.go

@@ -42,15 +42,15 @@ func (s *Service) rpcHandlerByTopicFromFork(forkIndex int) (map[string]rpcHandle
 	// Fulu: https://github.com/ethereum/consensus-specs/blob/dev/specs/fulu/p2p-interface.md#messages
 	if forkIndex >= version.Fulu {
 		return map[string]rpcHandler{
-			p2p.RPCStatusTopicV1:                   s.statusRPCHandler,
-			p2p.RPCGoodByeTopicV1:                  s.goodbyeRPCHandler,
-			p2p.RPCBlocksByRangeTopicV2:            s.beaconBlocksByRangeRPCHandler,
-			p2p.RPCBlocksByRootTopicV2:             s.beaconBlocksRootRPCHandler,
-			p2p.RPCPingTopicV1:                     s.pingHandler,
-			p2p.RPCMetaDataTopicV3:                 s.metaDataHandler, // Modified in Fulu
-			p2p.RPCBlobSidecarsByRootTopicV1:       s.blobSidecarByRootRPCHandler,
-			p2p.RPCBlobSidecarsByRangeTopicV1:      s.blobSidecarsByRangeRPCHandler,
-			p2p.RPCDataColumnSidecarsByRootTopicV1: s.dataColumnSidecarByRootRPCHandler, // Added in Fulu
+			p2p.RPCGoodByeTopicV1:                   s.goodbyeRPCHandler,
+			p2p.RPCBlocksByRangeTopicV2:             s.beaconBlocksByRangeRPCHandler,
+			p2p.RPCBlocksByRootTopicV2:              s.beaconBlocksRootRPCHandler,
+			p2p.RPCPingTopicV1:                      s.pingHandler,
+			p2p.RPCMetaDataTopicV3:                  s.metaDataHandler, // Modified in Fulu
+			p2p.RPCBlobSidecarsByRootTopicV1:        s.blobSidecarByRootRPCHandler,
+			p2p.RPCBlobSidecarsByRangeTopicV1:       s.blobSidecarsByRangeRPCHandler,
+			p2p.RPCDataColumnSidecarsByRootTopicV1:  s.dataColumnSidecarByRootRPCHandler,   // Added in Fulu
+			p2p.RPCDataColumnSidecarsByRangeTopicV1: s.dataColumnSidecarsByRangeRPCHandler, // Added in Fulu
 		}, nil
 	}
 

beacon-chain/sync/rpc_data_column_sidecars_by_range.go

@@ -0,0 +1,218 @@
+package sync
+
+import (
+	"context"
+	"slices"
+	"time"
+
+	p2ptypes "github.com/OffchainLabs/prysm/v6/beacon-chain/p2p/types"
+	"github.com/OffchainLabs/prysm/v6/config/params"
+	"github.com/OffchainLabs/prysm/v6/consensus-types/primitives"
+	"github.com/OffchainLabs/prysm/v6/monitoring/tracing"
+	"github.com/OffchainLabs/prysm/v6/monitoring/tracing/trace"
+	pb "github.com/OffchainLabs/prysm/v6/proto/prysm/v1alpha1"
+	libp2pcore "github.com/libp2p/go-libp2p/core"
+	"github.com/pkg/errors"
+
+	"github.com/sirupsen/logrus"
+)
+
+// We count a single request as a single rate limiting amount, regardless of the number of columns requested.
+const rateLimitingAmount = 1
+
+var notDataColumnsByRangeIdentifiersError = errors.New("not data columns by range identifiers")
+
+// dataColumnSidecarsByRangeRPCHandler looks up the request data columns from the database from a given start slot index
+func (s *Service) dataColumnSidecarsByRangeRPCHandler(ctx context.Context, msg interface{}, stream libp2pcore.Stream) error {
+	ctx, span := trace.StartSpan(ctx, "sync.DataColumnSidecarsByRangeHandler")
+	defer span.End()
+
+	// Check if the message type is the one expected.
+	request, ok := msg.(*pb.DataColumnSidecarsByRangeRequest)
+	if !ok {
+		return notDataColumnsByRangeIdentifiersError
+	}
+
+	ctx, cancel := context.WithTimeout(ctx, respTimeout)
+	defer cancel()
+
+	SetRPCStreamDeadlines(stream)
+	beaconConfig := params.BeaconConfig()
+	maxRequestDataColumnSidecars := beaconConfig.MaxRequestDataColumnSidecars
+	remotePeer := stream.Conn().RemotePeer()
+
+	requestedColumns := request.Columns
+
+	// Format log fields.
+	var requestedColumnsLog interface{} = "all"
+	if uint64(len(requestedColumns)) != beaconConfig.NumberOfColumns {
+		requestedColumnsLog = requestedColumns
+	}
+
+	log := log.WithFields(logrus.Fields{
+		"remotePeer":       remotePeer,
+		"requestedColumns": requestedColumnsLog,
+		"startSlot":        request.StartSlot,
+		"count":            request.Count,
+	})
+
+	// Validate the request regarding rate limiting.
+	if err := s.rateLimiter.validateRequest(stream, rateLimitingAmount); err != nil {
+		return errors.Wrap(err, "rate limiter validate request")
+	}
+
+	// Validate the request regarding its parameters.
+	rangeParameters, err := validateDataColumnsByRange(request, s.cfg.chain.CurrentSlot())
+	if err != nil {
+		s.writeErrorResponseToStream(responseCodeInvalidRequest, err.Error(), stream)
+		s.cfg.p2p.Peers().Scorers().BadResponsesScorer().Increment(remotePeer)
+		tracing.AnnotateError(span, err)
+		return errors.Wrap(err, "validate data columns by range")
+	}
+	if rangeParameters == nil {
+		log.Debug("No data columns by range to serve")
+		return nil
+	}
+
+	log.Debug("Serving data columns by range request")
+
+	// Ticker to stagger out large requests.
+	ticker := time.NewTicker(time.Second)
+
+	batcher, err := newBlockRangeBatcher(*rangeParameters, s.cfg.beaconDB, s.rateLimiter, s.cfg.chain.IsCanonical, ticker)
+	if err != nil {
+		s.writeErrorResponseToStream(responseCodeServerError, p2ptypes.ErrGeneric.Error(), stream)
+		tracing.AnnotateError(span, err)
+		return errors.Wrap(err, "new block range batcher")
+	}
+
+	// Derive the wanted columns for the request.
+	wantedColumns := make([]uint64, len(request.Columns))
+	copy(wantedColumns, request.Columns)
+
+	// Sort the wanted columns.
+	slices.Sort(wantedColumns)
+
+	var batch blockBatch
+	for batch, ok = batcher.next(ctx, stream); ok; batch, ok = batcher.next(ctx, stream) {
+		batchStart := time.Now()
+		maxRequestDataColumnSidecars, err = s.streamDataColumnBatch(ctx, batch, maxRequestDataColumnSidecars, wantedColumns, stream)
+		rpcDataColumnsByRangeResponseLatency.Observe(float64(time.Since(batchStart).Milliseconds()))
+		if err != nil {
+			return err
+		}
+
+		// Once the quota is reached, we're done serving the request.
+		if maxRequestDataColumnSidecars == 0 {
+			log.WithField("initialQuota", beaconConfig.MaxRequestDataColumnSidecars).Debug("Reached quota for data column sidecars by range request")
+			break
+		}
+	}
+
+	if err := batch.error(); err != nil {
+		log.WithError(err).Debug("error in DataColumnSidecarsByRange batch")
+
+		// If we hit a rate limit, the error response has already been written, and the stream is already closed.
+		if !errors.Is(err, p2ptypes.ErrRateLimited) {
+			s.writeErrorResponseToStream(responseCodeServerError, p2ptypes.ErrGeneric.Error(), stream)
+		}
+
+		tracing.AnnotateError(span, err)
+		return err
+	}
+
+	closeStream(stream, log)
+	return nil
+}
+
+func (s *Service) streamDataColumnBatch(ctx context.Context, batch blockBatch, quota uint64, wantedDataColumnIndices []uint64, stream libp2pcore.Stream) (uint64, error) {
+	_, span := trace.StartSpan(ctx, "sync.streamDataColumnBatch")
+	defer span.End()
+
+	// Defensive check to guard against underflow.
+	if quota == 0 {
+		return 0, nil
+	}
+
+	// Loop over the blocks in the batch.
+	for _, block := range batch.canonical() {
+		// Get the block blockRoot.
+		blockRoot := block.Root()
+
+		// Retrieve the data column sidecars from the store.
+		verifiedRODataColumns, err := s.cfg.dataColumnStorage.Get(blockRoot, wantedDataColumnIndices)
+		if err != nil {
+			s.writeErrorResponseToStream(responseCodeServerError, p2ptypes.ErrGeneric.Error(), stream)
+			return quota, errors.Wrapf(err, "get data column sidecars: block root %#x", blockRoot)
+		}
+
+		// Write the retrieved sidecars to the stream.
+		for _, verifiedRODataColumn := range verifiedRODataColumns {
+			sidecar := verifiedRODataColumn.DataColumnSidecar
+			SetStreamWriteDeadline(stream, defaultWriteDuration)
+
+			if err := WriteDataColumnSidecarChunk(stream, s.cfg.chain, s.cfg.p2p.Encoding(), sidecar); err != nil {
+				s.writeErrorResponseToStream(responseCodeServerError, p2ptypes.ErrGeneric.Error(), stream)
+				tracing.AnnotateError(span, err)
+				return quota, errors.Wrap(err, "write data column sidecar chunk")
+			}
+
+			s.rateLimiter.add(stream, rateLimitingAmount)
+			quota -= 1
+
+			// Stop streaming results once the quota of writes for the request is consumed.
+			if quota == 0 {
+				return 0, nil
+			}
+		}
+	}
+
+	return quota, nil
+}
+
+func validateDataColumnsByRange(request *pb.DataColumnSidecarsByRangeRequest, currentSlot primitives.Slot) (*rangeParams, error) {
+	startSlot, count := request.StartSlot, request.Count
+
+	if count == 0 {
+		return nil, errors.Wrap(p2ptypes.ErrInvalidRequest, "invalid request count parameter")
+	}
+
+	endSlot, err := request.StartSlot.SafeAdd(count - 1)
+	if err != nil {
+		return nil, errors.Wrap(p2ptypes.ErrInvalidRequest, "overflow start + count -1")
+	}
+
+	// Peers may overshoot the current slot when in initial sync,
+	// so we don't want to penalize them by treating the request as an error.
+	if startSlot > currentSlot {
+		return nil, nil
+	}
+
+	// Compute the oldest slot we'll allow a peer to request, based on the current slot.
+	minStartSlot, err := dataColumnsRPCMinValidSlot(currentSlot)
+	if err != nil {
+		return nil, errors.Wrap(p2ptypes.ErrInvalidRequest, "data columns RPC min valid slot")
+	}
+
+	// Return early if there is nothing to serve.
+	if endSlot < minStartSlot {
+		return nil, nil
+	}
+
+	// Do not serve sidecars for slots before the minimum valid slot or after the current slot.
+	startSlot = max(startSlot, minStartSlot)
+	endSlot = min(endSlot, currentSlot)
+
+	sizeMinusOne, err := endSlot.SafeSub(uint64(startSlot))
+	if err != nil {
+		return nil, errors.Errorf("overflow end - start: %d - %d - should never happen", endSlot, startSlot)
+	}
+
+	size, err := sizeMinusOne.SafeAdd(1)
+	if err != nil {
+		return nil, errors.Wrap(p2ptypes.ErrInvalidRequest, "overflow end - start + 1")
+	}
+
+	rangeParameters := &rangeParams{start: startSlot, end: endSlot, size: uint64(size)}
+	return rangeParameters, nil
+}

beacon-chain/sync/rpc_data_column_sidecars_by_range_test.go

@@ -0,0 +1,301 @@
+package sync
+
+import (
+	"context"
+	"fmt"
+	"io"
+	"math"
+	"sync"
+	"testing"
+	"time"
+
+	"github.com/libp2p/go-libp2p/core/network"
+	"github.com/libp2p/go-libp2p/core/protocol"
+	"github.com/pkg/errors"
+	"github.com/stretchr/testify/require"
+
+	chainMock "github.com/OffchainLabs/prysm/v6/beacon-chain/blockchain/testing"
+	"github.com/OffchainLabs/prysm/v6/beacon-chain/db/filesystem"
+	testDB "github.com/OffchainLabs/prysm/v6/beacon-chain/db/testing"
+	"github.com/OffchainLabs/prysm/v6/beacon-chain/p2p"
+	p2ptest "github.com/OffchainLabs/prysm/v6/beacon-chain/p2p/testing"
+	fieldparams "github.com/OffchainLabs/prysm/v6/config/fieldparams"
+	"github.com/OffchainLabs/prysm/v6/config/params"
+	"github.com/OffchainLabs/prysm/v6/consensus-types/blocks"
+	consensusblocks "github.com/OffchainLabs/prysm/v6/consensus-types/blocks"
+	"github.com/OffchainLabs/prysm/v6/consensus-types/primitives"
+	pb "github.com/OffchainLabs/prysm/v6/proto/prysm/v1alpha1"
+	"github.com/OffchainLabs/prysm/v6/runtime/version"
+	"github.com/OffchainLabs/prysm/v6/testing/util"
+)
+
+func TestDataColumnSidecarsByRangeRPCHandler(t *testing.T) {
+	ctx := context.Background()
+	t.Run("wrong message type", func(t *testing.T) {
+		service := &Service{}
+		err := service.dataColumnSidecarsByRangeRPCHandler(ctx, nil, nil)
+		require.ErrorIs(t, err, notDataColumnsByRangeIdentifiersError)
+	})
+
+	t.Run("invalid request", func(t *testing.T) {
+		slot := primitives.Slot(400)
+
+		localP2P, remoteP2P := p2ptest.NewTestP2P(t), p2ptest.NewTestP2P(t)
+
+		service := &Service{
+			cfg: &config{
+				p2p: localP2P,
+				chain: &chainMock.ChainService{
+					Slot: &slot,
+				},
+			},
+			rateLimiter: newRateLimiter(localP2P),
+		}
+
+		protocolID := protocol.ID(fmt.Sprintf("%s/ssz_snappy", p2p.RPCDataColumnSidecarsByRangeTopicV1))
+
+		var wg sync.WaitGroup
+		wg.Add(1)
+
+		remoteP2P.BHost.SetStreamHandler(protocolID, func(stream network.Stream) {
+			defer wg.Done()
+			code, _, err := readStatusCodeNoDeadline(stream, localP2P.Encoding())
+			require.NoError(t, err)
+			require.Equal(t, responseCodeInvalidRequest, code)
+		})
+
+		localP2P.Connect(remoteP2P)
+		stream, err := localP2P.BHost.NewStream(ctx, remoteP2P.BHost.ID(), protocolID)
+		require.NoError(t, err)
+
+		msg := &pb.DataColumnSidecarsByRangeRequest{
+			Count: 0, // Invalid count
+		}
+		require.Equal(t, true, localP2P.Peers().Scorers().BadResponsesScorer().Score(remoteP2P.PeerID()) >= 0)
+
+		err = service.dataColumnSidecarsByRangeRPCHandler(ctx, msg, stream)
+		require.NotNil(t, err)
+		require.Equal(t, true, localP2P.Peers().Scorers().BadResponsesScorer().Score(remoteP2P.PeerID()) < 0)
+
+		if util.WaitTimeout(&wg, 1*time.Second) {
+			t.Fatal("Did not receive stream within 1 sec")
+		}
+	})
+
+	t.Run("nominal", func(t *testing.T) {
+		params.SetupTestConfigCleanup(t)
+		beaconConfig := params.BeaconConfig()
+		beaconConfig.FuluForkEpoch = 0
+		params.OverrideBeaconConfig(beaconConfig)
+
+		slot := primitives.Slot(400)
+
+		params := []util.DataColumnParam{
+			{Slot: 10, Index: 1}, {Slot: 10, Index: 2}, {Slot: 10, Index: 3},
+			{Slot: 40, Index: 4}, {Slot: 40, Index: 6},
+			{Slot: 45, Index: 7}, {Slot: 45, Index: 8}, {Slot: 45, Index: 9},
+		}
+
+		_, verifiedRODataColumns := util.CreateTestVerifiedRoDataColumnSidecars(t, params)
+
+		storage := filesystem.NewEphemeralDataColumnStorage(t)
+		err := storage.Save(verifiedRODataColumns)
+		require.NoError(t, err)
+
+		localP2P, remoteP2P := p2ptest.NewTestP2P(t), p2ptest.NewTestP2P(t)
+		protocolID := protocol.ID(fmt.Sprintf("%s/ssz_snappy", p2p.RPCDataColumnSidecarsByRangeTopicV1))
+
+		roots := [][fieldparams.RootLength]byte{
+			verifiedRODataColumns[0].BlockRoot(),
+			verifiedRODataColumns[3].BlockRoot(),
+			verifiedRODataColumns[5].BlockRoot(),
+		}
+
+		slots := []primitives.Slot{
+			verifiedRODataColumns[0].Slot(),
+			verifiedRODataColumns[3].Slot(),
+			verifiedRODataColumns[5].Slot(),
+		}
+
+		beaconDB := testDB.SetupDB(t)
+		roBlocks := make([]blocks.ROBlock, 0, len(roots))
+		for i := range 3 {
+			signedBeaconBlockPb := util.NewBeaconBlock()
+			signedBeaconBlockPb.Block.Slot = slots[i]
+			if i != 0 {
+				signedBeaconBlockPb.Block.ParentRoot = roots[i-1][:]
+			}
+
+			signedBeaconBlock, err := consensusblocks.NewSignedBeaconBlock(signedBeaconBlockPb)
+			require.NoError(t, err)
+
+			// There is a discrepancy between the root of the beacon block and the rodata column root,
+			// but for the sake of this test, we actually don't care.
+			roblock, err := consensusblocks.NewROBlockWithRoot(signedBeaconBlock, roots[i])
+			require.NoError(t, err)
+
+			roBlocks = append(roBlocks, roblock)
+		}
+
+		err = beaconDB.SaveROBlocks(ctx, roBlocks, false /*cache*/)
+		require.NoError(t, err)
+
+		service := &Service{
+			cfg: &config{
+				p2p:      localP2P,
+				beaconDB: beaconDB,
+				chain: &chainMock.ChainService{
+					Slot: &slot,
+				},
+				dataColumnStorage: storage,
+			},
+			rateLimiter: newRateLimiter(localP2P),
+		}
+
+		ctxMap := ContextByteVersions{
+			[4]byte{245, 165, 253, 66}: version.Fulu,
+		}
+
+		root0 := verifiedRODataColumns[0].BlockRoot()
+		root3 := verifiedRODataColumns[3].BlockRoot()
+		root5 := verifiedRODataColumns[5].BlockRoot()
+
+		var wg sync.WaitGroup
+		wg.Add(1)
+
+		remoteP2P.BHost.SetStreamHandler(protocolID, func(stream network.Stream) {
+			defer wg.Done()
+
+			sidecars := make([]*blocks.RODataColumn, 0, 5)
+
+			for i := uint64(0); ; /* no stop condition */ i++ {
+				sidecar, err := readChunkedDataColumnSidecar(stream, remoteP2P, ctxMap)
+				if errors.Is(err, io.EOF) {
+					// End of stream.
+					break
+				}
+
+				require.NoError(t, err)
+				sidecars = append(sidecars, sidecar)
+			}
+
+			require.Equal(t, 8, len(sidecars))
+			require.Equal(t, root0, sidecars[0].BlockRoot())
+			require.Equal(t, root0, sidecars[1].BlockRoot())
+			require.Equal(t, root0, sidecars[2].BlockRoot())
+			require.Equal(t, root3, sidecars[3].BlockRoot())
+			require.Equal(t, root3, sidecars[4].BlockRoot())
+			require.Equal(t, root5, sidecars[5].BlockRoot())
+			require.Equal(t, root5, sidecars[6].BlockRoot())
+			require.Equal(t, root5, sidecars[7].BlockRoot())
+
+			require.Equal(t, uint64(1), sidecars[0].Index)
+			require.Equal(t, uint64(2), sidecars[1].Index)
+			require.Equal(t, uint64(3), sidecars[2].Index)
+			require.Equal(t, uint64(4), sidecars[3].Index)
+			require.Equal(t, uint64(6), sidecars[4].Index)
+			require.Equal(t, uint64(7), sidecars[5].Index)
+			require.Equal(t, uint64(8), sidecars[6].Index)
+			require.Equal(t, uint64(9), sidecars[7].Index)
+		})
+
+		localP2P.Connect(remoteP2P)
+		stream, err := localP2P.BHost.NewStream(ctx, remoteP2P.BHost.ID(), protocolID)
+		require.NoError(t, err)
+
+		msg := &pb.DataColumnSidecarsByRangeRequest{
+			StartSlot: 5,
+			Count:     50,
+			Columns:   []uint64{1, 2, 3, 4, 6, 7, 8, 9, 10},
+		}
+
+		err = service.dataColumnSidecarsByRangeRPCHandler(ctx, msg, stream)
+		require.NoError(t, err)
+	})
+
+}
+
+func TestValidateDataColumnsByRange(t *testing.T) {
+	maxUint := primitives.Slot(math.MaxUint64)
+
+	params.SetupTestConfigCleanup(t)
+	config := params.BeaconConfig()
+	config.FuluForkEpoch = 10
+	config.MinEpochsForDataColumnSidecarsRequest = 4096
+	params.OverrideBeaconConfig(config)
+
+	tests := []struct {
+		name        string
+		startSlot   primitives.Slot
+		count       uint64
+		currentSlot primitives.Slot
+		expected    *rangeParams
+		expectErr   bool
+		errContains string
+	}{
+		{
+			name:        "zero count returns error",
+			count:       0,
+			expectErr:   true,
+			errContains: "invalid request count parameter",
+		},
+		{
+			name:        "overflow in addition returns error",
+			startSlot:   maxUint - 5,
+			count:       10,
+			currentSlot: maxUint,
+			expectErr:   true,
+			errContains: "overflow start + count -1",
+		},
+		{
+			name:        "start greater than current returns nil",
+			startSlot:   150,
+			count:       10,
+			currentSlot: 100,
+			expected:    nil,
+			expectErr:   false,
+		},
+		{
+			name:        "end slot greater than min start slot returns nil",
+			startSlot:   150,
+			count:       100,
+			currentSlot: 300,
+			expected:    nil,
+			expectErr:   false,
+		},
+		{
+			name:        "range within limits",
+			startSlot:   350,
+			count:       10,
+			currentSlot: 400,
+			expected:    &rangeParams{start: 350, end: 359, size: 10},
+			expectErr:   false,
+		},
+		{
+			name:        "range exceeds limits",
+			startSlot:   0,
+			count:       10_000,
+			currentSlot: 400,
+			expected:    &rangeParams{start: 320, end: 400, size: 81},
+			expectErr:   false,
+		},
+	}
+
+	for _, tc := range tests {
+		t.Run(tc.name, func(t *testing.T) {
+			request := &pb.DataColumnSidecarsByRangeRequest{
+				StartSlot: tc.startSlot,
+				Count:     tc.count,
+			}
+
+			rangeParameters, err := validateDataColumnsByRange(request, tc.currentSlot)
+			if tc.expectErr {
+				require.ErrorContains(t, err, tc.errContains)
+				return
+			}
+
+			require.NoError(t, err)
+			require.Equal(t, tc.expected, rangeParameters)
+		})
+	}
+}

beacon-chain/sync/rpc_data_column_sidecars_by_root.go

@@ -12,6 +12,7 @@ import (
 	fieldparams "github.com/OffchainLabs/prysm/v6/config/fieldparams"
 	"github.com/OffchainLabs/prysm/v6/config/params"
 	"github.com/OffchainLabs/prysm/v6/consensus-types/primitives"
+	"github.com/OffchainLabs/prysm/v6/encoding/bytesutil"
 	"github.com/OffchainLabs/prysm/v6/monitoring/tracing"
 	"github.com/OffchainLabs/prysm/v6/monitoring/tracing/trace"
 	"github.com/OffchainLabs/prysm/v6/time/slots"
@@ -98,12 +99,15 @@ func (s *Service) dataColumnSidecarByRootRPCHandler(ctx context.Context, msg int
 	log.Debug("Serving data column sidecar by root request")
 
 	count := 0
-	for root, columns := range requestedColumnsByRoot {
+	for _, ident := range requestedColumnIdents {
 		if err := ctx.Err(); err != nil {
 			closeStream(stream, log)
 			return errors.Wrap(err, "context error")
 		}
 
+		root := bytesutil.ToBytes32(ident.BlockRoot)
+		columns := ident.Columns
+
 		// Throttle request processing to no more than batchSize/sec.
 		for range columns {
 			if ticker != nil && count != 0 && count%batchSize == 0 {
@@ -170,5 +174,10 @@ func dataColumnsRPCMinValidSlot(currentSlot primitives.Slot) (primitives.Slot, e
 		minStartEpoch = currEpoch - minReqEpochs
 	}
 
-	return slots.EpochStart(minStartEpoch)
+	epochStart, err := slots.EpochStart(minStartEpoch)
+	if err != nil {
+		return 0, errors.Wrapf(err, "epoch start for epoch %d", minStartEpoch)
+	}
+
+	return epochStart, nil
 }

beacon-chain/sync/rpc_data_column_sidecars_by_root_test.go

@@ -139,7 +139,7 @@ func TestDataColumnSidecarsByRootRPCHandler(t *testing.T) {
 			sidecars := make([]*blocks.RODataColumn, 0, 5)
 
 			for i := uint64(0); ; /* no stop condition */ i++ {
-				sidecar, err := readChunkedDataColumnSideCar(stream, remoteP2P, ctxMap)
+				sidecar, err := readChunkedDataColumnSidecar(stream, remoteP2P, ctxMap)
 				if errors.Is(err, io.EOF) {
 					// End of stream.
 					break
@@ -276,21 +276,28 @@ func TestDataColumnsRPCMinValidSlot(t *testing.T) {
 			expected:      primitives.Slot(math.MaxUint64),
 		},
 		{
-			name:          "Current epoch equals fork epoch",
+			name:          "Current epoch is before fulu fork epoch",
+			fuluForkEpoch: 10,
+			minReqEpochs:  5,
+			currentSlot:   primitives.Slot(8 * slotsPerEpoch),
+			expected:      primitives.Slot(10 * slotsPerEpoch),
+		},
+		{
+			name:          "Current epoch is fulu fork epoch",
 			fuluForkEpoch: 10,
 			minReqEpochs:  5,
 			currentSlot:   primitives.Slot(10 * slotsPerEpoch),
 			expected:      primitives.Slot(10 * slotsPerEpoch),
 		},
 		{
-			name:          "Current epoch less than minReqEpochs",
+			name:          "Current epoch between fulu fork epoch and minReqEpochs",
 			fuluForkEpoch: 10,
 			minReqEpochs:  20,
 			currentSlot:   primitives.Slot(15 * slotsPerEpoch),
 			expected:      primitives.Slot(10 * slotsPerEpoch),
 		},
 		{
-			name:          "Current epoch greater than minReqEpochs + fork epoch",
+			name:          "Current epoch after fulu fork epoch + minReqEpochs",
 			fuluForkEpoch: 10,
 			minReqEpochs:  5,
 			currentSlot:   primitives.Slot(20 * slotsPerEpoch),

beacon-chain/sync/rpc_metadata.go

@@ -17,7 +17,7 @@ import (
 	"github.com/prysmaticlabs/go-bitfield"
 )
 
-// metaDataHandler reads the incoming metadata rpc request from the peer.
+// metaDataHandler reads the incoming metadata RPC request from the peer.
 func (s *Service) metaDataHandler(_ context.Context, _ interface{}, stream libp2pcore.Stream) error {
 	SetRPCStreamDeadlines(stream)
 
@@ -70,7 +70,9 @@ func (s *Service) metaDataHandler(_ context.Context, _ interface{}, stream libp2
 	switch streamVersion {
 	case p2p.SchemaVersionV1:
 		switch metadataVersion {
-		case version.Altair, version.Deneb:
+		case version.Altair, version.Fulu:
+			// If the stream version corresponds to Phase 0 but our metadata
+			// corresponds to Altair or Fulu, convert our metadata to the Phase 0 one.
 			metadata = wrapper.WrappedMetadataV0(
 				&pb.MetaDataV0{
 					Attnets:   metadata.AttnetsBitfield(),
@@ -81,13 +83,18 @@ func (s *Service) metaDataHandler(_ context.Context, _ interface{}, stream libp2
 	case p2p.SchemaVersionV2:
 		switch metadataVersion {
 		case version.Phase0:
+			// If the stream version corresponds to Altair but our metadata
+			// corresponds to Phase 0, convert our metadata to the Altair one,
+			// and use a zeroed syncnets bitfield.
 			metadata = wrapper.WrappedMetadataV1(
 				&pb.MetaDataV1{
 					Attnets:   metadata.AttnetsBitfield(),
 					SeqNumber: metadata.SequenceNumber(),
 					Syncnets:  bitfield.Bitvector4{byte(0x00)},
 				})
-		case version.Deneb:
+		case version.Fulu:
+			// If the stream version corresponds to Altair but our metadata
+			// corresponds to Fulu, convert our metadata to the Altair one.
 			metadata = wrapper.WrappedMetadataV1(
 				&pb.MetaDataV1{
 					Attnets:   metadata.AttnetsBitfield(),
@@ -95,6 +102,32 @@ func (s *Service) metaDataHandler(_ context.Context, _ interface{}, stream libp2
 					Syncnets:  metadata.SyncnetsBitfield(),
 				})
 		}
+
+	case p2p.SchemaVersionV3:
+		switch metadataVersion {
+		case version.Phase0:
+			// If the stream version corresponds to Fulu but our metadata
+			// corresponds to Phase 0, convert our metadata to the Fulu one,
+			// and use a zeroed syncnets bitfield and custody group count.
+			metadata = wrapper.WrappedMetadataV2(
+				&pb.MetaDataV2{
+					Attnets:           metadata.AttnetsBitfield(),
+					SeqNumber:         metadata.SequenceNumber(),
+					Syncnets:          bitfield.Bitvector4{byte(0x00)},
+					CustodyGroupCount: 0,
+				})
+		case version.Altair:
+			// If the stream version corresponds to Fulu but our metadata
+			// corresponds to Altair, convert our metadata to the Fulu one and
+			// use a zeroed custody group count.
+			metadata = wrapper.WrappedMetadataV2(
+				&pb.MetaDataV2{
+					Attnets:           metadata.AttnetsBitfield(),
+					SeqNumber:         metadata.SequenceNumber(),
+					Syncnets:          metadata.SyncnetsBitfield(),
+					CustodyGroupCount: 0,
+				})
+		}
 	}
 
 	// Write the METADATA response into the stream.
@@ -164,12 +197,14 @@ func (s *Service) sendMetaDataRequest(ctx context.Context, peerID peer.ID) (meta
 	}
 
 	// Defensive check to ensure valid objects are being sent.
-	topicVersion := ""
+	var topicVersion string
 	switch msg.Version() {
 	case version.Phase0:
 		topicVersion = p2p.SchemaVersionV1
 	case version.Altair:
 		topicVersion = p2p.SchemaVersionV2
+	case version.Fulu:
+		topicVersion = p2p.SchemaVersionV3
 	}
 
 	// Validate the version of the topic.

beacon-chain/sync/rpc_metadata_test.go

@@ -1,6 +1,7 @@
 package sync
 
 import (
+	"context"
 	"sync"
 	"testing"
 	"time"
@@ -15,6 +16,7 @@ import (
 	leakybucket "github.com/OffchainLabs/prysm/v6/container/leaky-bucket"
 	"github.com/OffchainLabs/prysm/v6/encoding/ssz/equality"
 	pb "github.com/OffchainLabs/prysm/v6/proto/prysm/v1alpha1"
+	"github.com/OffchainLabs/prysm/v6/proto/prysm/v1alpha1/metadata"
 	"github.com/OffchainLabs/prysm/v6/testing/assert"
 	"github.com/OffchainLabs/prysm/v6/testing/require"
 	"github.com/OffchainLabs/prysm/v6/testing/util"
@@ -22,6 +24,7 @@ import (
 	"github.com/libp2p/go-libp2p/core/network"
 	"github.com/libp2p/go-libp2p/core/protocol"
 	libp2pquic "github.com/libp2p/go-libp2p/p2p/transport/quic"
+	"github.com/prysmaticlabs/go-bitfield"
 )
 
 func TestMetaDataRPCHandler_ReceivesMetadata(t *testing.T) {
@@ -76,158 +79,241 @@ func TestMetaDataRPCHandler_ReceivesMetadata(t *testing.T) {
 	}
 }
 
-func TestMetadataRPCHandler_SendsMetadata(t *testing.T) {
-	p1 := p2ptest.NewTestP2P(t)
-	p2 := p2ptest.NewTestP2P(t)
-	p1.Connect(p2)
-	assert.Equal(t, 1, len(p1.BHost.Network().Peers()), "Expected peers to be connected")
-	bitfield := [8]byte{'A', 'B'}
-	p2.LocalMetadata = wrapper.WrappedMetadataV0(&pb.MetaDataV0{
-		SeqNumber: 2,
-		Attnets:   bitfield[:],
-	})
-
-	// Set up a head state in the database with data we expect.
-	chain := &mock.ChainService{Genesis: time.Now(), ValidatorsRoot: [32]byte{}}
-	d := db.SetupDB(t)
-	r := &Service{
+func createService(peer p2p.P2P, chain *mock.ChainService) *Service {
+	return &Service{
 		cfg: &config{
-			beaconDB: d,
-			p2p:      p1,
-			chain:    chain,
-			clock:    startup.NewClock(chain.Genesis, chain.ValidatorsRoot),
+			p2p:   peer,
+			chain: chain,
+			clock: startup.NewClock(chain.Genesis, chain.ValidatorsRoot),
 		},
-		rateLimiter: newRateLimiter(p1),
-	}
-
-	r2 := &Service{
-		cfg: &config{
-			beaconDB: d,
-			p2p:      p2,
-			chain:    &mock.ChainService{Genesis: time.Now(), ValidatorsRoot: [32]byte{}},
-		},
-		rateLimiter: newRateLimiter(p2),
-	}
-
-	// Setup streams
-	pcl := protocol.ID(p2p.RPCMetaDataTopicV1 + r.cfg.p2p.Encoding().ProtocolSuffix())
-	topic := string(pcl)
-	r.rateLimiter.limiterMap[topic] = leakybucket.NewCollector(1, 1, time.Second, false)
-	r2.rateLimiter.limiterMap[topic] = leakybucket.NewCollector(1, 1, time.Second, false)
-
-	var wg sync.WaitGroup
-	wg.Add(1)
-	p2.BHost.SetStreamHandler(pcl, func(stream network.Stream) {
-		defer wg.Done()
-		assert.NoError(t, r2.metaDataHandler(t.Context(), new(interface{}), stream))
-	})
-
-	md, err := r.sendMetaDataRequest(t.Context(), p2.BHost.ID())
-	assert.NoError(t, err)
-
-	if !equality.DeepEqual(md.InnerObject(), p2.LocalMetadata.InnerObject()) {
-		t.Fatalf("MetadataV0 unequal, received %v but wanted %v", md, p2.LocalMetadata)
-	}
-
-	if util.WaitTimeout(&wg, 1*time.Second) {
-		t.Fatal("Did not receive stream within 1 sec")
-	}
-
-	conns := p1.BHost.Network().ConnsToPeer(p2.BHost.ID())
-	if len(conns) == 0 {
-		t.Error("Peer is disconnected despite receiving a valid ping")
+		rateLimiter: newRateLimiter(peer),
 	}
 }
 
-func TestMetadataRPCHandler_SendsMetadataAltair(t *testing.T) {
+func TestMetadataRPCHandler_SendMetadataRequest(t *testing.T) {
+	const (
+		requestTimeout    = 1 * time.Second
+		seqNumber         = 2
+		custodyGroupCount = 4
+	)
+
+	attnets := []byte{'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H'}
+	syncnets := []byte{0x4}
+
+	// Configure the test beacon chain.
 	params.SetupTestConfigCleanup(t)
-	bCfg := params.BeaconConfig().Copy()
-	bCfg.AltairForkEpoch = 5
-	params.OverrideBeaconConfig(bCfg)
+	beaconChainConfig := params.BeaconConfig().Copy()
+	beaconChainConfig.AltairForkEpoch = 5
+	beaconChainConfig.FuluForkEpoch = 15
+	params.OverrideBeaconConfig(beaconChainConfig)
 	params.BeaconConfig().InitializeForkSchedule()
 
-	p1 := p2ptest.NewTestP2P(t)
-	p2 := p2ptest.NewTestP2P(t)
-	p1.Connect(p2)
-	assert.Equal(t, 1, len(p1.BHost.Network().Peers()), "Expected peers to be connected")
-	bitfield := [8]byte{'A', 'B'}
-	p2.LocalMetadata = wrapper.WrappedMetadataV0(&pb.MetaDataV0{
-		SeqNumber: 2,
-		Attnets:   bitfield[:],
-	})
+	// Compute the number of seconds in an epoch.
+	secondsPerEpoch := oneEpoch()
 
-	// Set up a head state in the database with data we expect.
-	d := db.SetupDB(t)
-	chain := &mock.ChainService{Genesis: time.Now().Add(-5 * oneEpoch()), ValidatorsRoot: [32]byte{}}
-	r := &Service{
-		cfg: &config{
-			beaconDB: d,
-			p2p:      p1,
-			chain:    chain,
-			clock:    startup.NewClock(chain.Genesis, chain.ValidatorsRoot),
+	testCases := []struct {
+		name                                             string
+		topic                                            string
+		epochsSinceGenesisPeer1, epochsSinceGenesisPeer2 int
+		metadataPeer2, expected                          metadata.Metadata
+	}{
+		{
+			name:                    "Phase0-Phase0",
+			topic:                   p2p.RPCMetaDataTopicV1,
+			epochsSinceGenesisPeer1: 0,
+			epochsSinceGenesisPeer2: 0,
+			metadataPeer2: wrapper.WrappedMetadataV0(&pb.MetaDataV0{
+				SeqNumber: seqNumber,
+				Attnets:   attnets,
+			}),
+			expected: wrapper.WrappedMetadataV0(&pb.MetaDataV0{
+				SeqNumber: seqNumber,
+				Attnets:   attnets,
+			}),
 		},
-		rateLimiter: newRateLimiter(p1),
-	}
-
-	chain2 := &mock.ChainService{Genesis: time.Now().Add(-5 * oneEpoch()), ValidatorsRoot: [32]byte{}}
-	r2 := &Service{
-		cfg: &config{
-			beaconDB: d,
-			p2p:      p2,
-			chain:    chain2,
-			clock:    startup.NewClock(chain2.Genesis, chain2.ValidatorsRoot),
+		{
+			name:                    "Phase0-Altair",
+			topic:                   p2p.RPCMetaDataTopicV1,
+			epochsSinceGenesisPeer1: 0,
+			epochsSinceGenesisPeer2: 5,
+			metadataPeer2: wrapper.WrappedMetadataV1(&pb.MetaDataV1{
+				SeqNumber: seqNumber,
+				Attnets:   attnets,
+				Syncnets:  syncnets,
+			}),
+			expected: wrapper.WrappedMetadataV0(&pb.MetaDataV0{
+				SeqNumber: seqNumber,
+				Attnets:   attnets,
+			}),
+		},
+		{
+			name:                    "Phase0-Fulu",
+			topic:                   p2p.RPCMetaDataTopicV1,
+			epochsSinceGenesisPeer1: 0,
+			epochsSinceGenesisPeer2: 15,
+			metadataPeer2: wrapper.WrappedMetadataV2(&pb.MetaDataV2{
+				SeqNumber:         seqNumber,
+				Attnets:           attnets,
+				Syncnets:          syncnets,
+				CustodyGroupCount: custodyGroupCount,
+			}),
+			expected: wrapper.WrappedMetadataV0(&pb.MetaDataV0{
+				SeqNumber: seqNumber,
+				Attnets:   attnets,
+			}),
+		},
+		{
+			name:                    "Altair-Phase0",
+			topic:                   p2p.RPCMetaDataTopicV2,
+			epochsSinceGenesisPeer1: 5,
+			epochsSinceGenesisPeer2: 0,
+			metadataPeer2: wrapper.WrappedMetadataV0(&pb.MetaDataV0{
+				SeqNumber: seqNumber,
+				Attnets:   attnets,
+			}),
+			expected: wrapper.WrappedMetadataV1(&pb.MetaDataV1{
+				SeqNumber: seqNumber,
+				Attnets:   attnets,
+				Syncnets:  bitfield.Bitvector4{byte(0x00)},
+			}),
+		},
+		{
+			name:                    "Altair-Altair",
+			topic:                   p2p.RPCMetaDataTopicV2,
+			epochsSinceGenesisPeer1: 5,
+			epochsSinceGenesisPeer2: 5,
+			metadataPeer2: wrapper.WrappedMetadataV1(&pb.MetaDataV1{
+				SeqNumber: seqNumber,
+				Attnets:   attnets,
+				Syncnets:  syncnets,
+			}),
+			expected: wrapper.WrappedMetadataV1(&pb.MetaDataV1{
+				SeqNumber: seqNumber,
+				Attnets:   attnets,
+				Syncnets:  syncnets,
+			}),
+		},
+		{
+			name:                    "Altair-Fulu",
+			topic:                   p2p.RPCMetaDataTopicV2,
+			epochsSinceGenesisPeer1: 5,
+			epochsSinceGenesisPeer2: 15,
+			metadataPeer2: wrapper.WrappedMetadataV2(&pb.MetaDataV2{
+				SeqNumber:         seqNumber,
+				Attnets:           attnets,
+				Syncnets:          syncnets,
+				CustodyGroupCount: custodyGroupCount,
+			}),
+			expected: wrapper.WrappedMetadataV1(&pb.MetaDataV1{
+				SeqNumber: seqNumber,
+				Attnets:   attnets,
+				Syncnets:  syncnets,
+			}),
+		},
+		{
+			name:                    "Fulu-Phase0",
+			topic:                   p2p.RPCMetaDataTopicV3,
+			epochsSinceGenesisPeer1: 15,
+			epochsSinceGenesisPeer2: 0,
+			metadataPeer2: wrapper.WrappedMetadataV0(&pb.MetaDataV0{
+				SeqNumber: seqNumber,
+				Attnets:   attnets,
+			}),
+			expected: wrapper.WrappedMetadataV2(&pb.MetaDataV2{
+				SeqNumber:         seqNumber,
+				Attnets:           attnets,
+				Syncnets:          bitfield.Bitvector4{byte(0x00)},
+				CustodyGroupCount: 0,
+			}),
+		},
+		{
+			name:                    "Fulu-Altair",
+			topic:                   p2p.RPCMetaDataTopicV3,
+			epochsSinceGenesisPeer1: 15,
+			epochsSinceGenesisPeer2: 5,
+			metadataPeer2: wrapper.WrappedMetadataV1(&pb.MetaDataV1{
+				SeqNumber: seqNumber,
+				Attnets:   attnets,
+				Syncnets:  syncnets,
+			}),
+			expected: wrapper.WrappedMetadataV2(&pb.MetaDataV2{
+				SeqNumber:         seqNumber,
+				Attnets:           attnets,
+				Syncnets:          syncnets,
+				CustodyGroupCount: 0,
+			}),
+		},
+		{
+			name:                    "Fulu-Fulu",
+			topic:                   p2p.RPCMetaDataTopicV3,
+			epochsSinceGenesisPeer1: 15,
+			epochsSinceGenesisPeer2: 15,
+			metadataPeer2: wrapper.WrappedMetadataV2(&pb.MetaDataV2{
+				SeqNumber:         seqNumber,
+				Attnets:           attnets,
+				Syncnets:          syncnets,
+				CustodyGroupCount: custodyGroupCount,
+			}),
+			expected: wrapper.WrappedMetadataV2(&pb.MetaDataV2{
+				SeqNumber:         seqNumber,
+				Attnets:           attnets,
+				Syncnets:          syncnets,
+				CustodyGroupCount: custodyGroupCount,
+			}),
 		},
-		rateLimiter: newRateLimiter(p2),
 	}
 
-	// Setup streams
-	pcl := protocol.ID(p2p.RPCMetaDataTopicV2 + r.cfg.p2p.Encoding().ProtocolSuffix())
-	topic := string(pcl)
-	r.rateLimiter.limiterMap[topic] = leakybucket.NewCollector(2, 2, time.Second, false)
-	r2.rateLimiter.limiterMap[topic] = leakybucket.NewCollector(2, 2, time.Second, false)
+	for _, tc := range testCases {
+		t.Run(tc.name, func(t *testing.T) {
+			var wg sync.WaitGroup
 
-	var wg sync.WaitGroup
-	wg.Add(1)
-	p2.BHost.SetStreamHandler(pcl, func(stream network.Stream) {
-		defer wg.Done()
-		err := r2.metaDataHandler(t.Context(), new(interface{}), stream)
-		assert.NoError(t, err)
-	})
+			ctx := context.Background()
 
-	_, err := r.sendMetaDataRequest(t.Context(), p2.BHost.ID())
-	assert.NoError(t, err)
+			// Setup and connect peers.
+			peer1, peer2 := p2ptest.NewTestP2P(t), p2ptest.NewTestP2P(t)
+			peer1.Connect(peer2)
 
-	if util.WaitTimeout(&wg, 1*time.Second) {
-		t.Fatal("Did not receive stream within 1 sec")
-	}
+			// Ensure the peers are connected.
+			peersCount := len(peer1.BHost.Network().Peers())
+			require.Equal(t, 1, peersCount, "Expected peers to be connected")
 
-	// Fix up peer with the correct metadata.
-	p2.LocalMetadata = wrapper.WrappedMetadataV1(&pb.MetaDataV1{
-		SeqNumber: 2,
-		Attnets:   bitfield[:],
-		Syncnets:  []byte{0x0},
-	})
+			// Setup sync services.
+			genesisPeer1 := time.Now().Add(-time.Duration(tc.epochsSinceGenesisPeer1) * secondsPerEpoch)
+			genesisPeer2 := time.Now().Add(-time.Duration(tc.epochsSinceGenesisPeer2) * secondsPerEpoch)
 
-	wg.Add(1)
-	p2.BHost.SetStreamHandler(pcl, func(stream network.Stream) {
-		defer wg.Done()
-		assert.NoError(t, r2.metaDataHandler(t.Context(), new(interface{}), stream))
-	})
+			chainPeer1 := &mock.ChainService{Genesis: genesisPeer1, ValidatorsRoot: [32]byte{}}
+			chainPeer2 := &mock.ChainService{Genesis: genesisPeer2, ValidatorsRoot: [32]byte{}}
 
-	md, err := r.sendMetaDataRequest(t.Context(), p2.BHost.ID())
-	assert.NoError(t, err)
+			servicePeer1 := createService(peer1, chainPeer1)
+			servicePeer2 := createService(peer2, chainPeer2)
 
-	if !equality.DeepEqual(md.InnerObject(), p2.LocalMetadata.InnerObject()) {
-		t.Fatalf("MetadataV1 unequal, received %v but wanted %v", md, p2.LocalMetadata)
-	}
+			// Define the behavior of peer2 when receiving a METADATA request.
+			protocolSuffix := servicePeer2.cfg.p2p.Encoding().ProtocolSuffix()
+			protocolID := protocol.ID(tc.topic + protocolSuffix)
+			peer2.LocalMetadata = tc.metadataPeer2
 
-	if util.WaitTimeout(&wg, 1*time.Second) {
-		t.Fatal("Did not receive stream within 1 sec")
-	}
+			wg.Add(1)
+			peer2.BHost.SetStreamHandler(protocolID, func(stream network.Stream) {
+				defer wg.Done()
+				err := servicePeer2.metaDataHandler(ctx, new(interface{}), stream)
+				require.NoError(t, err)
+			})
 
-	conns := p1.BHost.Network().ConnsToPeer(p2.BHost.ID())
-	if len(conns) == 0 {
-		t.Error("Peer is disconnected despite receiving a valid ping")
+			// Send a METADATA request from peer1 to peer2.
+			actual, err := servicePeer1.sendMetaDataRequest(ctx, peer2.BHost.ID())
+			require.NoError(t, err)
+
+			// Wait until the METADATA request is received by peer2 or timeout.
+			timeOutReached := util.WaitTimeout(&wg, requestTimeout)
+			require.Equal(t, false, timeOutReached, "Did not receive METADATA request within timeout")
+
+			// Compare the received METADATA object with the expected METADATA object.
+			require.DeepSSZEqual(t, tc.expected.InnerObject(), actual.InnerObject(), "Metadata unequal")
+
+			// Ensure the peers are still connected.
+			peersCount = len(peer1.BHost.Network().Peers())
+			assert.Equal(t, 1, peersCount, "Expected peers to be connected")
+		})
 	}
 }
 

beacon-chain/sync/rpc_send_request.go

@@ -4,12 +4,14 @@ import (
 	"context"
 	"fmt"
 	"io"
+	"slices"
 
 	"github.com/OffchainLabs/prysm/v6/beacon-chain/blockchain"
 	"github.com/OffchainLabs/prysm/v6/beacon-chain/p2p"
 	"github.com/OffchainLabs/prysm/v6/beacon-chain/p2p/encoder"
 	p2ptypes "github.com/OffchainLabs/prysm/v6/beacon-chain/p2p/types"
 	"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"
 	"github.com/OffchainLabs/prysm/v6/consensus-types/interfaces"
@@ -30,18 +32,24 @@ var errBlobUnmarshal = errors.New("Could not unmarshal chunk-encoded blob")
 // Any error from the following declaration block should result in peer downscoring.
 var (
 	// ErrInvalidFetchedData is used to signal that an error occurred which should result in peer downscoring.
-	ErrInvalidFetchedData             = errors.New("invalid data returned from peer")
-	errBlobIndexOutOfBounds           = errors.Wrap(verification.ErrBlobInvalid, "blob index out of range")
-	errMaxRequestBlobSidecarsExceeded = errors.Wrap(verification.ErrBlobInvalid, "peer exceeded req blob chunk tx limit")
-	errChunkResponseSlotNotAsc        = errors.Wrap(verification.ErrBlobInvalid, "blob slot not higher than previous block root")
-	errChunkResponseIndexNotAsc       = errors.Wrap(verification.ErrBlobInvalid, "blob indices for a block must start at 0 and increase by 1")
-	errUnrequested                    = errors.Wrap(verification.ErrBlobInvalid, "received BlobSidecar in response that was not requested")
-	errBlobResponseOutOfBounds        = errors.Wrap(verification.ErrBlobInvalid, "received BlobSidecar with slot outside BlobSidecarsByRangeRequest bounds")
-	errChunkResponseBlockMismatch     = errors.Wrap(verification.ErrBlobInvalid, "blob block details do not match")
-	errChunkResponseParentMismatch    = errors.Wrap(verification.ErrBlobInvalid, "parent root for response element doesn't match previous element root")
-	errDataColumnChunkedReadFailure   = errors.New("failed to read stream of chunk-encoded data columns")
+	ErrInvalidFetchedData                    = errors.New("invalid data returned from peer")
+	errBlobIndexOutOfBounds                  = errors.Wrap(verification.ErrBlobInvalid, "blob index out of range")
+	errMaxRequestBlobSidecarsExceeded        = errors.Wrap(verification.ErrBlobInvalid, "peer exceeded req blob chunk tx limit")
+	errChunkResponseSlotNotAsc               = errors.Wrap(verification.ErrBlobInvalid, "blob slot not higher than previous block root")
+	errChunkResponseIndexNotAsc              = errors.Wrap(verification.ErrBlobInvalid, "blob indices for a block must start at 0 and increase by 1")
+	errUnrequested                           = errors.Wrap(verification.ErrBlobInvalid, "received BlobSidecar in response that was not requested")
+	errBlobResponseOutOfBounds               = errors.Wrap(verification.ErrBlobInvalid, "received BlobSidecar with slot outside BlobSidecarsByRangeRequest bounds")
+	errChunkResponseBlockMismatch            = errors.Wrap(verification.ErrBlobInvalid, "blob block details do not match")
+	errChunkResponseParentMismatch           = errors.Wrap(verification.ErrBlobInvalid, "parent root for response element doesn't match previous element root")
+	errDataColumnChunkedReadFailure          = errors.New("failed to read stream of chunk-encoded data columns")
+	errMaxRequestDataColumnSidecarsExceeded  = errors.New("count of requested data column sidecars exceeds MAX_REQUEST_DATA_COLUMN_SIDECARS")
+	errMaxResponseDataColumnSidecarsExceeded = errors.New("peer returned more data column sidecars than requested")
 )
 
+// ------
+// Blocks
+// ------
+
 // BeaconBlockProcessor defines a block processing function, which allows to start utilizing
 // blocks even before all blocks are ready.
 type BeaconBlockProcessor func(block interfaces.ReadOnlySignedBeaconBlock) error
@@ -155,6 +163,14 @@ func SendBeaconBlocksByRootRequest(
 	return blocks, nil
 }
 
+// -------------
+// Blob sidecars
+// -------------
+
+// BlobResponseValidation represents a function that can validate aspects of a single unmarshaled blob sidecar
+// that was received from a peer in response to an rpc request.
+type BlobResponseValidation func(blocks.ROBlob) error
+
 func SendBlobsByRangeRequest(ctx context.Context, tor blockchain.TemporalOracle, p2pApi p2p.SenderEncoder, pid peer.ID, ctxMap ContextByteVersions, req *ethpb.BlobSidecarsByRangeRequest, bvs ...BlobResponseValidation) ([]blocks.ROBlob, error) {
 	topic, err := p2p.TopicFromMessage(p2p.BlobSidecarsByRangeName, slots.ToEpoch(tor.CurrentSlot()))
 	if err != nil {
@@ -216,10 +232,6 @@ func SendBlobSidecarByRoot(
 	return readChunkEncodedBlobs(stream, p2pApi.Encoding(), ctxMap, blobValidatorFromRootReq(req), max)
 }
 
-// BlobResponseValidation represents a function that can validate aspects of a single unmarshaled blob
-// that was received from a peer in response to an rpc request.
-type BlobResponseValidation func(blocks.ROBlob) error
-
 func composeBlobValidations(vf ...BlobResponseValidation) BlobResponseValidation {
 	return func(blob blocks.ROBlob) error {
 		for i := range vf {
@@ -385,10 +397,258 @@ func readChunkedBlobSidecar(stream network.Stream, encoding encoder.NetworkEncod
 	return rob, nil
 }
 
-func readChunkedDataColumnSideCar(
+// --------------------
+// Data column sidecars
+// --------------------
+
+// SendDataColumnSidecarsByRangeRequest sends a request for data column sidecars by range
+// and returns the fetched data column sidecars.
+func SendDataColumnSidecarsByRangeRequest(
+	ctx context.Context,
+	tor blockchain.TemporalOracle,
+	p2pApi p2p.P2P,
+	pid peer.ID,
+	ctxMap ContextByteVersions,
+	request *ethpb.DataColumnSidecarsByRangeRequest,
+) ([]blocks.RODataColumn, error) {
+	// Return early if nothing to request.
+	if request == nil || request.Count == 0 || len(request.Columns) == 0 {
+		return nil, nil
+	}
+
+	beaconConfig := params.BeaconConfig()
+	numberOfColumns := beaconConfig.NumberOfColumns
+	maxRequestDataColumnSidecars := params.BeaconConfig().MaxRequestDataColumnSidecars
+
+	// Check if we do not request too many sidecars.
+	columnsCount := uint64(len(request.Columns))
+	totalCount := request.Count * columnsCount
+	if totalCount > maxRequestDataColumnSidecars {
+		return nil, errors.Wrapf(errMaxRequestDataColumnSidecarsExceeded, "requestedCount=%d, allowedCount=%d", totalCount, maxRequestDataColumnSidecars)
+	}
+
+	// Build the topic.
+	currentSlot := tor.CurrentSlot()
+	currentEpoch := slots.ToEpoch(currentSlot)
+	topic, err := p2p.TopicFromMessage(p2p.DataColumnSidecarsByRangeName, currentEpoch)
+	if err != nil {
+		return nil, errors.Wrap(err, "topic from message")
+	}
+
+	// Build the logs.
+	var columnsLog interface{} = "all"
+	if columnsCount < numberOfColumns {
+		columns := request.Columns
+		slices.Sort(columns)
+		columnsLog = columns
+	}
+
+	log := log.WithFields(logrus.Fields{
+		"peer":       pid,
+		"topic":      topic,
+		"startSlot":  request.StartSlot,
+		"count":      request.Count,
+		"columns":    columnsLog,
+		"totalCount": totalCount,
+	})
+
+	// Send the request.
+	stream, err := p2pApi.Send(ctx, request, topic, pid)
+	if err != nil {
+		return nil, errors.Wrap(err, "p2p send")
+	}
+	defer closeStream(stream, log)
+
+	// Read the data column sidecars from the stream.
+	roDataColumns := make([]blocks.RODataColumn, 0, totalCount)
+	for range totalCount {
+		// Avoid reading extra chunks if the context is done.
+		if err := ctx.Err(); err != nil {
+			return nil, err
+		}
+
+		validatorSlotWithinBounds, err := isSidecarSlotWithinBounds(request)
+		if err != nil {
+			return nil, errors.Wrap(err, "is sidecar slot within bounds")
+		}
+
+		roDataColumn, err := readChunkedDataColumnSidecar(
+			stream, p2pApi, ctxMap,
+			validatorSlotWithinBounds,
+			isSidecarIndexRequested(request),
+		)
+		if errors.Is(err, io.EOF) {
+			return roDataColumns, nil
+		}
+		if err != nil {
+			return nil, errors.Wrap(err, "read chunked data column sidecar")
+		}
+
+		if roDataColumn == nil {
+			return nil, errors.New("nil data column sidecar, should never happen")
+		}
+
+		roDataColumns = append(roDataColumns, *roDataColumn)
+	}
+
+	// All requested sidecars were delivered by the peer. Expecting EOF.
+	if _, err := readChunkedDataColumnSidecar(stream, p2pApi, ctxMap); !errors.Is(err, io.EOF) {
+		return nil, errors.Wrapf(errMaxResponseDataColumnSidecarsExceeded, "requestedCount=%d", totalCount)
+	}
+
+	return roDataColumns, nil
+}
+
+// isSidecarSlotWithinBounds verifies that the slot of the data column sidecar is within the bounds of the request.
+func isSidecarSlotWithinBounds(request *ethpb.DataColumnSidecarsByRangeRequest) (DataColumnResponseValidation, error) {
+	// endSlot is exclusive (while request.StartSlot is inclusive).
+	endSlot, err := request.StartSlot.SafeAdd(request.Count)
+	if err != nil {
+		return nil, errors.Wrap(err, "calculate end slot")
+	}
+
+	validator := func(sidecar blocks.RODataColumn) error {
+		slot := sidecar.Slot()
+
+		if !(request.StartSlot <= slot && slot < endSlot) {
+			return errors.Errorf("data column sidecar slot %d out of range [%d, %d[", slot, request.StartSlot, endSlot)
+		}
+
+		return nil
+	}
+
+	return validator, nil
+}
+
+// isSidecarIndexRequested verifies that the index of the data column sidecar is found in the requested indices.
+func isSidecarIndexRequested(request *ethpb.DataColumnSidecarsByRangeRequest) DataColumnResponseValidation {
+	requestedIndices := make(map[uint64]bool)
+	for _, col := range request.Columns {
+		requestedIndices[col] = true
+	}
+
+	return func(sidecar blocks.RODataColumn) error {
+		columnIndex := sidecar.Index
+		if !requestedIndices[columnIndex] {
+			return errors.Errorf("data column sidecar index %d not found in requested indices", columnIndex)
+		}
+
+		return nil
+	}
+}
+
+// SendDataColumnSidecarsByRootRequest sends a request for data column sidecars by root
+// and returns the fetched data column sidecars.
+func SendDataColumnSidecarsByRootRequest(
+	ctx context.Context,
+	tor blockchain.TemporalOracle,
+	p2pApi p2p.P2P,
+	pid peer.ID,
+	ctxMap ContextByteVersions,
+	request p2ptypes.DataColumnsByRootIdentifiers,
+) ([]blocks.RODataColumn, error) {
+	// Return early if the request is nil.
+	if request == nil {
+		return nil, nil
+	}
+
+	// Compute how many sidecars are requested.
+	count := uint64(0)
+	for _, identifier := range request {
+		count += uint64(len(identifier.Columns))
+	}
+
+	// Return early if nothing to request.
+	if count == 0 {
+		return nil, nil
+	}
+
+	// Verify that the request count is within the maximum allowed.
+	maxRequestDataColumnSidecars := params.BeaconConfig().MaxRequestDataColumnSidecars
+	if count > maxRequestDataColumnSidecars {
+		return nil, errors.Wrapf(errMaxRequestDataColumnSidecarsExceeded, "current: %d, max: %d", count, maxRequestDataColumnSidecars)
+	}
+
+	// Get the topic for the request.
+	topic, err := p2p.TopicFromMessage(p2p.DataColumnSidecarsByRootName, slots.ToEpoch(tor.CurrentSlot()))
+	if err != nil {
+		return nil, errors.Wrap(err, "topic from message")
+	}
+
+	// Send the request to the peer.
+	stream, err := p2pApi.Send(ctx, request, topic, pid)
+	if err != nil {
+		return nil, errors.Wrap(err, "p2p api send")
+	}
+	defer closeStream(stream, log)
+
+	// Read the data column sidecars from the stream.
+	roDataColumns := make([]blocks.RODataColumn, 0, count)
+
+	// Read the data column sidecars from the stream.
+	for range count {
+		roDataColumn, err := readChunkedDataColumnSidecar(stream, p2pApi, ctxMap, isSidecarIndexRootRequested(request))
+		if errors.Is(err, io.EOF) {
+			return roDataColumns, nil
+		}
+		if err != nil {
+			return nil, errors.Wrap(err, "read chunked data column sidecar")
+		}
+
+		if roDataColumn == nil {
+			return nil, errors.Wrap(err, "nil data column sidecar, should never happen")
+		}
+
+		roDataColumns = append(roDataColumns, *roDataColumn)
+	}
+
+	// All requested sidecars were delivered by the peer. Expecting EOF.
+	if _, err := readChunkedDataColumnSidecar(stream, p2pApi, ctxMap); !errors.Is(err, io.EOF) {
+		return nil, errors.Wrapf(errMaxResponseDataColumnSidecarsExceeded, "requestedCount=%d", count)
+	}
+
+	return roDataColumns, nil
+}
+
+func isSidecarIndexRootRequested(request p2ptypes.DataColumnsByRootIdentifiers) DataColumnResponseValidation {
+	columnsIndexFromRoot := make(map[[fieldparams.RootLength]byte]map[uint64]bool)
+
+	for _, sidecar := range request {
+		blockRoot := bytesutil.ToBytes32(sidecar.BlockRoot)
+		if columnsIndexFromRoot[blockRoot] == nil {
+			columnsIndexFromRoot[blockRoot] = make(map[uint64]bool)
+		}
+
+		for _, column := range sidecar.Columns {
+			columnsIndexFromRoot[blockRoot][column] = true
+		}
+	}
+
+	return func(sidecar blocks.RODataColumn) error {
+		root, index := sidecar.BlockRoot(), sidecar.Index
+		indices, ok := columnsIndexFromRoot[root]
+
+		if !ok {
+			return errors.Errorf("root #%x returned by peer but not requested", root)
+		}
+
+		if !indices[index] {
+			return errors.Errorf("index %d for root #%x returned by peer but not requested", index, root)
+		}
+
+		return nil
+	}
+}
+
+// DataColumnResponseValidation represents a function that can validate aspects of a single unmarshaled data column sidecar
+// that was received from a peer in response to an rpc request.
+type DataColumnResponseValidation func(column blocks.RODataColumn) error
+
+func readChunkedDataColumnSidecar(
 	stream network.Stream,
 	p2pApi p2p.P2P,
 	ctxMap ContextByteVersions,
+	validationFunctions ...DataColumnResponseValidation,
 ) (*blocks.RODataColumn, error) {
 	// Read the status code from the stream.
 	statusCode, errMessage, err := ReadStatusCode(stream, p2pApi.Encoding())
@@ -432,5 +692,12 @@ func readChunkedDataColumnSideCar(
 		return nil, errors.Wrap(err, "new read only data column")
 	}
 
+	// Run validation functions.
+	for _, validationFunction := range validationFunctions {
+		if err := validationFunction(roDataColumn); err != nil {
+			return nil, errors.Wrap(err, "validation function")
+		}
+	}
+
 	return &roDataColumn, nil
 }

beacon-chain/sync/rpc_send_request_test.go

@@ -5,12 +5,15 @@ import (
 	"errors"
 	"fmt"
 	"io"
+	"sync"
 	"testing"
 	"time"
 
 	"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/p2p/types"
 	p2pTypes "github.com/OffchainLabs/prysm/v6/beacon-chain/p2p/types"
+	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"
@@ -20,6 +23,7 @@ import (
 	"github.com/OffchainLabs/prysm/v6/consensus-types/primitives"
 	"github.com/OffchainLabs/prysm/v6/encoding/bytesutil"
 	ethpb "github.com/OffchainLabs/prysm/v6/proto/prysm/v1alpha1"
+	"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"
@@ -882,3 +886,745 @@ func TestSendBlobsByRangeRequest(t *testing.T) {
 func TestErrInvalidFetchedDataDistinction(t *testing.T) {
 	require.Equal(t, false, errors.Is(ErrInvalidFetchedData, verification.ErrBlobInvalid))
 }
+
+func TestSendDataColumnSidecarsByRangeRequest(t *testing.T) {
+	nilTestCases := []struct {
+		name    string
+		request *ethpb.DataColumnSidecarsByRangeRequest
+	}{
+		{
+			name:    "nil request",
+			request: nil,
+		},
+		{
+			name:    "count is 0",
+			request: &ethpb.DataColumnSidecarsByRangeRequest{},
+		},
+		{
+			name:    "columns is nil",
+			request: &ethpb.DataColumnSidecarsByRangeRequest{Count: 1},
+		},
+	}
+
+	for _, tc := range nilTestCases {
+		t.Run(tc.name, func(t *testing.T) {
+			actual, err := SendDataColumnSidecarsByRangeRequest(t.Context(), nil, nil, "aRandomPID", nil, tc.request)
+			require.NoError(t, err)
+			require.IsNil(t, actual)
+		})
+	}
+
+	t.Run("too many columns in request", func(t *testing.T) {
+		params.SetupTestConfigCleanup(t)
+		beaconConfig := params.BeaconConfig()
+		beaconConfig.MaxRequestDataColumnSidecars = 0
+		params.OverrideBeaconConfig(beaconConfig)
+
+		request := &ethpb.DataColumnSidecarsByRangeRequest{Count: 1, Columns: []uint64{1, 2, 3}}
+		_, err := SendDataColumnSidecarsByRangeRequest(t.Context(), nil, nil, "aRandomPID", nil, request)
+		require.ErrorContains(t, errMaxRequestDataColumnSidecarsExceeded.Error(), err)
+	})
+
+	type slotIndex struct {
+		Slot  primitives.Slot
+		Index uint64
+	}
+
+	createSidecar := func(slotIndex slotIndex) *ethpb.DataColumnSidecar {
+		const count = 4
+		kzgCommitmentsInclusionProof := make([][]byte, 0, count)
+		for range count {
+			kzgCommitmentsInclusionProof = append(kzgCommitmentsInclusionProof, make([]byte, 32))
+		}
+
+		return &ethpb.DataColumnSidecar{
+			Index: slotIndex.Index,
+			SignedBlockHeader: &ethpb.SignedBeaconBlockHeader{
+				Header: &ethpb.BeaconBlockHeader{
+					Slot:       slotIndex.Slot,
+					ParentRoot: make([]byte, fieldparams.RootLength),
+					StateRoot:  make([]byte, fieldparams.RootLength),
+					BodyRoot:   make([]byte, fieldparams.RootLength),
+				},
+				Signature: make([]byte, fieldparams.BLSSignatureLength),
+			},
+			KzgCommitmentsInclusionProof: kzgCommitmentsInclusionProof,
+		}
+	}
+
+	testCases := []struct {
+		name          string
+		slotIndices   []slotIndex
+		expectedError error
+	}{
+		{
+			name: "too many responses",
+			slotIndices: []slotIndex{
+				{Slot: 0, Index: 1},
+				{Slot: 0, Index: 2},
+				{Slot: 0, Index: 3},
+				{Slot: 1, Index: 1},
+				{Slot: 1, Index: 2},
+				{Slot: 1, Index: 3},
+				{Slot: 0, Index: 3}, // Duplicate
+			},
+			expectedError: errMaxResponseDataColumnSidecarsExceeded,
+		},
+		{
+			name: "perfect match",
+			slotIndices: []slotIndex{
+				{Slot: 0, Index: 1},
+				{Slot: 0, Index: 2},
+				{Slot: 0, Index: 3},
+				{Slot: 1, Index: 1},
+				{Slot: 1, Index: 2},
+				{Slot: 1, Index: 3},
+			},
+		},
+		{
+			name: "few responses than maximum possible",
+			slotIndices: []slotIndex{
+				{Slot: 0, Index: 1},
+				{Slot: 0, Index: 2},
+				{Slot: 0, Index: 3},
+				{Slot: 1, Index: 1},
+				{Slot: 1, Index: 2},
+			},
+		},
+	}
+
+	for _, tc := range testCases {
+		t.Run(tc.name, func(t *testing.T) {
+			protocol := fmt.Sprintf("%s/ssz_snappy", p2p.RPCDataColumnSidecarsByRangeTopicV1)
+			clock := startup.NewClock(time.Now(), [fieldparams.RootLength]byte{})
+
+			p1, p2 := p2ptest.NewTestP2P(t), p2ptest.NewTestP2P(t)
+			p1.Connect(p2)
+
+			expected := make([]*ethpb.DataColumnSidecar, 0, len(tc.slotIndices))
+			for _, slotIndex := range tc.slotIndices {
+				sidecar := createSidecar(slotIndex)
+				expected = append(expected, sidecar)
+			}
+
+			requestSent := &ethpb.DataColumnSidecarsByRangeRequest{
+				StartSlot: 0,
+				Count:     2,
+				Columns:   []uint64{1, 3, 2},
+			}
+
+			var wg sync.WaitGroup
+			wg.Add(1)
+
+			p2.SetStreamHandler(protocol, func(stream network.Stream) {
+				wg.Done()
+
+				requestReceived := new(ethpb.DataColumnSidecarsByRangeRequest)
+				err := p2.Encoding().DecodeWithMaxLength(stream, requestReceived)
+				assert.NoError(t, err)
+				assert.DeepSSZEqual(t, requestSent, requestReceived)
+
+				for _, sidecar := range expected {
+					err := WriteDataColumnSidecarChunk(stream, clock, p2.Encoding(), sidecar)
+					assert.NoError(t, err)
+				}
+
+				err = stream.CloseWrite()
+				assert.NoError(t, err)
+			})
+
+			ctx := t.Context()
+			ctxMap := ContextByteVersions{[4]byte{245, 165, 253, 66}: version.Fulu}
+
+			actual, err := SendDataColumnSidecarsByRangeRequest(ctx, clock, p1, p2.PeerID(), ctxMap, requestSent)
+			if tc.expectedError != nil {
+				require.ErrorContains(t, tc.expectedError.Error(), err)
+				if util.WaitTimeout(&wg, time.Second) {
+					t.Fatal("Did not receive stream within 1 sec")
+				}
+
+				return
+			}
+
+			require.Equal(t, len(expected), len(actual))
+			for i := range expected {
+				require.DeepSSZEqual(t, expected[i], actual[i].DataColumnSidecar)
+			}
+		})
+	}
+}
+
+func TestIsSidecarSlotWithinBounds(t *testing.T) {
+	request := &ethpb.DataColumnSidecarsByRangeRequest{
+		StartSlot: 10,
+		Count:     10,
+	}
+
+	validator, err := isSidecarSlotWithinBounds(request)
+	require.NoError(t, err)
+
+	testCases := []struct {
+		name            string
+		slot            primitives.Slot
+		isErrorExpected bool
+	}{
+		{
+			name:            "too soon",
+			slot:            9,
+			isErrorExpected: true,
+		},
+		{
+			name:            "too late",
+			slot:            20,
+			isErrorExpected: true,
+		},
+		{
+			name:            "within bounds",
+			slot:            15,
+			isErrorExpected: false,
+		},
+	}
+
+	for _, tc := range testCases {
+		t.Run(tc.name, func(t *testing.T) {
+			const count = 4
+			kzgCommitmentsInclusionProof := make([][]byte, 0, count)
+			for range count {
+				kzgCommitmentsInclusionProof = append(kzgCommitmentsInclusionProof, make([]byte, 32))
+			}
+
+			sidecarPb := &ethpb.DataColumnSidecar{
+				SignedBlockHeader: &ethpb.SignedBeaconBlockHeader{
+					Header: &ethpb.BeaconBlockHeader{
+						Slot:       tc.slot,
+						ParentRoot: make([]byte, fieldparams.RootLength),
+						StateRoot:  make([]byte, fieldparams.RootLength),
+						BodyRoot:   make([]byte, fieldparams.RootLength),
+					},
+					Signature: make([]byte, fieldparams.BLSSignatureLength),
+				},
+				KzgCommitmentsInclusionProof: kzgCommitmentsInclusionProof,
+			}
+
+			sidecar, err := blocks.NewRODataColumn(sidecarPb)
+			require.NoError(t, err)
+
+			err = validator(sidecar)
+			if tc.isErrorExpected {
+				require.NotNil(t, err)
+				return
+			}
+
+			require.NoError(t, err)
+		})
+	}
+}
+
+func TestIsSidecarIndexRequested(t *testing.T) {
+	request := &ethpb.DataColumnSidecarsByRangeRequest{
+		Columns: []uint64{2, 9, 4},
+	}
+
+	validator := isSidecarIndexRequested(request)
+
+	testCases := []struct {
+		name            string
+		index           uint64
+		isErrorExpected bool
+	}{
+		{
+			name:            "not requested",
+			index:           1,
+			isErrorExpected: true,
+		},
+		{
+			name:            "requested",
+			index:           9,
+			isErrorExpected: false,
+		},
+	}
+
+	for _, tc := range testCases {
+		t.Run(tc.name, func(t *testing.T) {
+			const count = 4
+			kzgCommitmentsInclusionProof := make([][]byte, 0, count)
+			for range count {
+				kzgCommitmentsInclusionProof = append(kzgCommitmentsInclusionProof, make([]byte, 32))
+			}
+
+			sidecarPb := &ethpb.DataColumnSidecar{
+				SignedBlockHeader: &ethpb.SignedBeaconBlockHeader{
+					Header: &ethpb.BeaconBlockHeader{
+						Slot:       0,
+						ParentRoot: make([]byte, fieldparams.RootLength),
+						StateRoot:  make([]byte, fieldparams.RootLength),
+						BodyRoot:   make([]byte, fieldparams.RootLength),
+					},
+					Signature: make([]byte, fieldparams.BLSSignatureLength),
+				},
+				KzgCommitmentsInclusionProof: kzgCommitmentsInclusionProof,
+				Index:                        tc.index,
+			}
+
+			sidecar, err := blocks.NewRODataColumn(sidecarPb)
+			require.NoError(t, err)
+
+			err = validator(sidecar)
+			if tc.isErrorExpected {
+				require.NotNil(t, err)
+				return
+			}
+
+			require.NoError(t, err)
+		})
+	}
+}
+
+func TestSendDataColumnSidecarsByRootRequest(t *testing.T) {
+	nilTestCases := []struct {
+		name    string
+		request p2ptypes.DataColumnsByRootIdentifiers
+	}{
+		{
+			name:    "nil request",
+			request: nil,
+		},
+		{
+			name:    "count is 0",
+			request: p2ptypes.DataColumnsByRootIdentifiers{{}, {}},
+		},
+	}
+
+	for _, tc := range nilTestCases {
+		t.Run(tc.name, func(t *testing.T) {
+			actual, err := SendDataColumnSidecarsByRootRequest(t.Context(), nil, nil, "aRandomPID", nil, tc.request)
+			require.NoError(t, err)
+			require.IsNil(t, actual)
+		})
+	}
+
+	t.Run("too many columns in request", func(t *testing.T) {
+		params.SetupTestConfigCleanup(t)
+		beaconConfig := params.BeaconConfig()
+		beaconConfig.MaxRequestDataColumnSidecars = 4
+		params.OverrideBeaconConfig(beaconConfig)
+
+		request := p2ptypes.DataColumnsByRootIdentifiers{
+			{Columns: []uint64{1, 2, 3}},
+			{Columns: []uint64{4, 5, 6}},
+		}
+
+		_, err := SendDataColumnSidecarsByRootRequest(t.Context(), nil, nil, "aRandomPID", nil, request)
+		require.ErrorContains(t, errMaxRequestDataColumnSidecarsExceeded.Error(), err)
+	})
+
+	type slotIndex struct {
+		Slot  primitives.Slot
+		Index uint64
+	}
+
+	createSidecar := func(rootIndex slotIndex) blocks.RODataColumn {
+		const count = 4
+		kzgCommitmentsInclusionProof := make([][]byte, 0, count)
+		for range count {
+			kzgCommitmentsInclusionProof = append(kzgCommitmentsInclusionProof, make([]byte, 32))
+		}
+
+		sidecarPb := &ethpb.DataColumnSidecar{
+			Index: rootIndex.Index,
+			SignedBlockHeader: &ethpb.SignedBeaconBlockHeader{
+				Header: &ethpb.BeaconBlockHeader{
+					ParentRoot: make([]byte, fieldparams.RootLength),
+					StateRoot:  make([]byte, fieldparams.RootLength),
+					BodyRoot:   make([]byte, fieldparams.RootLength),
+				},
+				Signature: make([]byte, fieldparams.BLSSignatureLength),
+			},
+			KzgCommitmentsInclusionProof: kzgCommitmentsInclusionProof,
+		}
+
+		roSidecar, err := blocks.NewRODataColumn(sidecarPb)
+		require.NoError(t, err)
+
+		return roSidecar
+	}
+
+	testCases := []struct {
+		name          string
+		slotIndices   []slotIndex
+		expectedError error
+	}{
+		{
+			name: "too many responses",
+			slotIndices: []slotIndex{
+				{Slot: 1, Index: 1},
+				{Slot: 1, Index: 2},
+				{Slot: 1, Index: 3},
+				{Slot: 2, Index: 1},
+				{Slot: 2, Index: 2},
+				{Slot: 2, Index: 3},
+				{Slot: 1, Index: 3}, // Duplicate
+			},
+			expectedError: errMaxResponseDataColumnSidecarsExceeded,
+		},
+		{
+			name: "perfect match",
+			slotIndices: []slotIndex{
+				{Slot: 1, Index: 1},
+				{Slot: 1, Index: 2},
+				{Slot: 1, Index: 3},
+				{Slot: 2, Index: 1},
+				{Slot: 2, Index: 2},
+				{Slot: 2, Index: 3},
+			},
+		},
+		{
+			name: "few responses than maximum possible",
+			slotIndices: []slotIndex{
+				{Slot: 1, Index: 1},
+				{Slot: 1, Index: 2},
+				{Slot: 1, Index: 3},
+				{Slot: 2, Index: 1},
+				{Slot: 2, Index: 2},
+			},
+		},
+	}
+
+	for _, tc := range testCases {
+		t.Run(tc.name, func(t *testing.T) {
+			protocol := fmt.Sprintf("%s/ssz_snappy", p2p.RPCDataColumnSidecarsByRootTopicV1)
+			clock := startup.NewClock(time.Now(), [fieldparams.RootLength]byte{})
+
+			p1, p2 := p2ptest.NewTestP2P(t), p2ptest.NewTestP2P(t)
+			p1.Connect(p2)
+
+			expected := make([]blocks.RODataColumn, 0, len(tc.slotIndices))
+			for _, slotIndex := range tc.slotIndices {
+				roSidecar := createSidecar(slotIndex)
+				expected = append(expected, roSidecar)
+			}
+
+			blockRoot1, blockRoot2 := expected[0].BlockRoot(), expected[3].BlockRoot()
+
+			sentRequest := p2ptypes.DataColumnsByRootIdentifiers{
+				{BlockRoot: blockRoot1[:], Columns: []uint64{1, 2, 3}},
+				{BlockRoot: blockRoot2[:], Columns: []uint64{1, 2, 3}},
+			}
+
+			var wg sync.WaitGroup
+			wg.Add(1)
+
+			p2.SetStreamHandler(protocol, func(stream network.Stream) {
+				wg.Done()
+
+				requestReceived := new(p2ptypes.DataColumnsByRootIdentifiers)
+				err := p2.Encoding().DecodeWithMaxLength(stream, requestReceived)
+				assert.NoError(t, err)
+
+				require.Equal(t, len(sentRequest), len(*requestReceived))
+				for i := range sentRequest {
+					require.DeepSSZEqual(t, (sentRequest)[i], (*requestReceived)[i])
+				}
+
+				for _, sidecar := range expected {
+					err := WriteDataColumnSidecarChunk(stream, clock, p2.Encoding(), sidecar.DataColumnSidecar)
+					assert.NoError(t, err)
+				}
+
+				err = stream.CloseWrite()
+				assert.NoError(t, err)
+			})
+
+			ctx := t.Context()
+			ctxMap := ContextByteVersions{[4]byte{245, 165, 253, 66}: version.Fulu}
+
+			actual, err := SendDataColumnSidecarsByRootRequest(ctx, clock, p1, p2.PeerID(), ctxMap, sentRequest)
+			if tc.expectedError != nil {
+				require.ErrorContains(t, tc.expectedError.Error(), err)
+				if util.WaitTimeout(&wg, time.Second) {
+					t.Fatal("Did not receive stream within 1 sec")
+				}
+
+				return
+			}
+
+			require.Equal(t, len(expected), len(actual))
+			for i := range expected {
+				require.DeepSSZEqual(t, expected[i], actual[i])
+			}
+		})
+	}
+}
+
+func TestIsSidecarIndexRootRequested(t *testing.T) {
+	testCases := []struct {
+		name            string
+		root            [fieldparams.RootLength]byte
+		index           uint64
+		isErrorExpected bool
+	}{
+		{
+			name:            "non requested root",
+			root:            [fieldparams.RootLength]byte{2},
+			isErrorExpected: true,
+		},
+		{
+			name:            "non requested index",
+			root:            [fieldparams.RootLength]byte{1},
+			index:           3,
+			isErrorExpected: true,
+		},
+		{
+			name:            "nominal",
+			root:            [fieldparams.RootLength]byte{1},
+			index:           2,
+			isErrorExpected: false,
+		},
+	}
+
+	request := types.DataColumnsByRootIdentifiers{
+		{BlockRoot: []byte{1}, Columns: []uint64{1, 2}},
+	}
+
+	validator := isSidecarIndexRootRequested(request)
+
+	for _, tc := range testCases {
+		t.Run(tc.name, func(t *testing.T) {
+			const count = 4
+			kzgCommitmentsInclusionProof := make([][]byte, 0, count)
+			for range count {
+				kzgCommitmentsInclusionProof = append(kzgCommitmentsInclusionProof, make([]byte, 32))
+			}
+
+			sidecarPb := &ethpb.DataColumnSidecar{
+				SignedBlockHeader: &ethpb.SignedBeaconBlockHeader{
+					Header: &ethpb.BeaconBlockHeader{
+						ParentRoot: make([]byte, fieldparams.RootLength),
+						StateRoot:  make([]byte, fieldparams.RootLength),
+						BodyRoot:   make([]byte, fieldparams.RootLength),
+					},
+					Signature: make([]byte, fieldparams.BLSSignatureLength),
+				},
+				KzgCommitmentsInclusionProof: kzgCommitmentsInclusionProof,
+				Index:                        tc.index,
+			}
+
+			// There is a discrepancy between `tc.root` and the real root,
+			// but we don't care about it here.
+			sidecar, err := blocks.NewRODataColumnWithRoot(sidecarPb, tc.root)
+			require.NoError(t, err)
+
+			err = validator(sidecar)
+			if tc.isErrorExpected {
+				require.NotNil(t, err)
+				return
+			}
+
+			require.NoError(t, err)
+		})
+	}
+}
+
+func TestReadChunkedDataColumnSidecar(t *testing.T) {
+	t.Run("non nil status code", func(t *testing.T) {
+		const reason = "a dummy reason"
+
+		p1, p2 := p2ptest.NewTestP2P(t), p2ptest.NewTestP2P(t)
+
+		var wg sync.WaitGroup
+		wg.Add(1)
+		p2.SetStreamHandler(p2p.RPCDataColumnSidecarsByRootTopicV1, func(stream network.Stream) {
+			defer wg.Done()
+
+			_, err := readChunkedDataColumnSidecar(stream, p2, nil)
+			require.ErrorContains(t, reason, err)
+		})
+
+		p1.Connect(p2)
+
+		stream, err := p1.BHost.NewStream(t.Context(), p2.PeerID(), p2p.RPCDataColumnSidecarsByRootTopicV1)
+		require.NoError(t, err)
+
+		writeErrorResponseToStream(responseCodeInvalidRequest, reason, stream, p1)
+
+		if util.WaitTimeout(&wg, time.Second) {
+			t.Fatal("Did not receive stream within 1 sec")
+		}
+	})
+
+	t.Run("unrecognized fork digest", func(t *testing.T) {
+		p1, p2 := p2ptest.NewTestP2P(t), p2ptest.NewTestP2P(t)
+
+		var wg sync.WaitGroup
+		wg.Add(1)
+		p2.SetStreamHandler(p2p.RPCDataColumnSidecarsByRootTopicV1, func(stream network.Stream) {
+			defer wg.Done()
+
+			_, err := readChunkedDataColumnSidecar(stream, p2, ContextByteVersions{})
+			require.ErrorContains(t, "unrecognized fork digest", err)
+		})
+
+		p1.Connect(p2)
+
+		stream, err := p1.BHost.NewStream(t.Context(), p2.PeerID(), p2p.RPCDataColumnSidecarsByRootTopicV1)
+		require.NoError(t, err)
+
+		_, err = stream.Write([]byte{responseCodeSuccess})
+		require.NoError(t, err)
+
+		err = writeContextToStream([]byte{42, 42, 42, 42}, stream)
+		require.NoError(t, err)
+
+		if util.WaitTimeout(&wg, time.Second) {
+			t.Fatal("Did not receive stream within 1 sec")
+		}
+	})
+
+	t.Run("before fulu", func(t *testing.T) {
+		p1, p2 := p2ptest.NewTestP2P(t), p2ptest.NewTestP2P(t)
+
+		var wg sync.WaitGroup
+		wg.Add(1)
+		p2.SetStreamHandler(p2p.RPCDataColumnSidecarsByRootTopicV1, func(stream network.Stream) {
+			defer wg.Done()
+
+			_, err := readChunkedDataColumnSidecar(stream, p2, ContextByteVersions{[4]byte{1, 2, 3, 4}: version.Phase0})
+			require.ErrorContains(t, "unexpected context bytes", err)
+		})
+
+		p1.Connect(p2)
+
+		stream, err := p1.BHost.NewStream(t.Context(), p2.PeerID(), p2p.RPCDataColumnSidecarsByRootTopicV1)
+		require.NoError(t, err)
+
+		_, err = stream.Write([]byte{responseCodeSuccess})
+		require.NoError(t, err)
+
+		err = writeContextToStream([]byte{1, 2, 3, 4}, stream)
+		require.NoError(t, err)
+
+		if util.WaitTimeout(&wg, time.Second) {
+			t.Fatal("Did not receive stream within 1 sec")
+		}
+	})
+
+	t.Run("one validation failed", func(t *testing.T) {
+		const reason = "a dummy reason"
+
+		p1, p2 := p2ptest.NewTestP2P(t), p2ptest.NewTestP2P(t)
+
+		var wg sync.WaitGroup
+		wg.Add(1)
+		p2.SetStreamHandler(p2p.RPCDataColumnSidecarsByRootTopicV1, func(stream network.Stream) {
+			defer wg.Done()
+
+			validationOne := func(column blocks.RODataColumn) error {
+				return nil
+			}
+
+			validationTwo := func(column blocks.RODataColumn) error {
+				return errors.New(reason)
+			}
+
+			_, err := readChunkedDataColumnSidecar(
+				stream,
+				p2,
+				ContextByteVersions{[4]byte{1, 2, 3, 4}: version.Fulu},
+				validationOne, // OK
+				validationTwo, // Fail
+			)
+
+			require.ErrorContains(t, reason, err)
+		})
+
+		p1.Connect(p2)
+
+		stream, err := p1.BHost.NewStream(t.Context(), p2.PeerID(), p2p.RPCDataColumnSidecarsByRootTopicV1)
+		require.NoError(t, err)
+
+		const count = 4
+		kzgCommitmentsInclusionProof := make([][]byte, 0, count)
+		for range count {
+			kzgCommitmentsInclusionProof = append(kzgCommitmentsInclusionProof, make([]byte, 32))
+		}
+
+		// Success response code.
+		_, err = stream.Write([]byte{responseCodeSuccess})
+		require.NoError(t, err)
+
+		// Fork digest.
+		err = writeContextToStream([]byte{1, 2, 3, 4}, stream)
+		require.NoError(t, err)
+
+		// Sidecar.
+		_, err = p1.Encoding().EncodeWithMaxLength(stream, &ethpb.DataColumnSidecar{
+			SignedBlockHeader: &ethpb.SignedBeaconBlockHeader{
+				Header: &ethpb.BeaconBlockHeader{
+					ParentRoot: make([]byte, fieldparams.RootLength),
+					StateRoot:  make([]byte, fieldparams.RootLength),
+					BodyRoot:   make([]byte, fieldparams.RootLength),
+				},
+				Signature: make([]byte, fieldparams.BLSSignatureLength),
+			},
+			KzgCommitmentsInclusionProof: kzgCommitmentsInclusionProof,
+		})
+		require.NoError(t, err)
+
+		if util.WaitTimeout(&wg, time.Minute) {
+			t.Fatal("Did not receive stream within 1 sec")
+		}
+	})
+
+	t.Run("nominal", func(t *testing.T) {
+		p1, p2 := p2ptest.NewTestP2P(t), p2ptest.NewTestP2P(t)
+
+		const count = 4
+		kzgCommitmentsInclusionProof := make([][]byte, 0, count)
+		for range count {
+			kzgCommitmentsInclusionProof = append(kzgCommitmentsInclusionProof, make([]byte, 32))
+		}
+
+		expected := &ethpb.DataColumnSidecar{
+			SignedBlockHeader: &ethpb.SignedBeaconBlockHeader{
+				Header: &ethpb.BeaconBlockHeader{
+					ParentRoot: make([]byte, fieldparams.RootLength),
+					StateRoot:  make([]byte, fieldparams.RootLength),
+					BodyRoot:   make([]byte, fieldparams.RootLength),
+				},
+				Signature: make([]byte, fieldparams.BLSSignatureLength),
+			},
+			KzgCommitmentsInclusionProof: kzgCommitmentsInclusionProof,
+		}
+
+		var wg sync.WaitGroup
+		wg.Add(1)
+		p2.SetStreamHandler(p2p.RPCDataColumnSidecarsByRootTopicV1, func(stream network.Stream) {
+			defer wg.Done()
+
+			actual, err := readChunkedDataColumnSidecar(stream, p2, ContextByteVersions{[4]byte{1, 2, 3, 4}: version.Fulu})
+			require.NoError(t, err)
+			require.DeepSSZEqual(t, expected, actual.DataColumnSidecar)
+		})
+
+		p1.Connect(p2)
+
+		stream, err := p1.BHost.NewStream(t.Context(), p2.PeerID(), p2p.RPCDataColumnSidecarsByRootTopicV1)
+		require.NoError(t, err)
+
+		// Success response code.
+		_, err = stream.Write([]byte{responseCodeSuccess})
+		require.NoError(t, err)
+
+		// Fork digest.
+		err = writeContextToStream([]byte{1, 2, 3, 4}, stream)
+		require.NoError(t, err)
+
+		// Sidecar.
+		_, err = p1.Encoding().EncodeWithMaxLength(stream, expected)
+		require.NoError(t, err)
+
+		if util.WaitTimeout(&wg, time.Minute) {
+			t.Fatal("Did not receive stream within 1 sec")
+		}
+	})
+}

beacon-chain/sync/service.go

@@ -10,6 +10,8 @@ import (
 	"time"
 
 	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/crypto/rand"
 	lru "github.com/hashicorp/golang-lru"
 	pubsub "github.com/libp2p/go-libp2p-pubsub"
 	libp2pcore "github.com/libp2p/go-libp2p/core"
@@ -103,12 +105,15 @@ type config struct {
 	stateNotifier           statefeed.Notifier
 	blobStorage             *filesystem.BlobStorage
 	dataColumnStorage       *filesystem.DataColumnStorage
+	custodyInfo             *peerdas.CustodyInfo
+	batchVerifierLimit      int
 }
 
 // This defines the interface for interacting with block chain service
 type blockchainService interface {
 	blockchain.BlockReceiver
 	blockchain.BlobReceiver
+	blockchain.DataColumnReceiver
 	blockchain.HeadFetcher
 	blockchain.FinalizationFetcher
 	blockchain.ForkFetcher
@@ -166,6 +171,8 @@ type Service struct {
 	newBlobVerifier                  verification.NewBlobVerifier
 	newColumnsVerifier               verification.NewDataColumnsVerifier
 	availableBlocker                 coverage.AvailableBlocker
+	reconstructionLock               sync.Mutex
+	reconstructionRandGen            *rand.Rand
 	ctxMap                           ContextByteVersions
 	slasherEnabled                   bool
 	lcStore                          *lightClient.Store
@@ -176,15 +183,15 @@ type Service struct {
 func NewService(ctx context.Context, opts ...Option) *Service {
 	ctx, cancel := context.WithCancel(ctx)
 	r := &Service{
-		ctx:                  ctx,
-		cancel:               cancel,
-		chainStarted:         abool.New(),
-		cfg:                  &config{clock: startup.NewClock(time.Unix(0, 0), [32]byte{})},
-		slotToPendingBlocks:  gcache.New(pendingBlockExpTime /* exp time */, 0 /* disable janitor */),
-		seenPendingBlocks:    make(map[[32]byte]bool),
-		blkRootToPendingAtts: make(map[[32]byte][]ethpb.SignedAggregateAttAndProof),
-		signatureChan:        make(chan *signatureVerifier, verifierLimit),
-		dataColumnLogCh:      make(chan dataColumnLogEntry, 1000),
+		ctx:                   ctx,
+		cancel:                cancel,
+		chainStarted:          abool.New(),
+		cfg:                   &config{clock: startup.NewClock(time.Unix(0, 0), [32]byte{})},
+		slotToPendingBlocks:   gcache.New(pendingBlockExpTime /* exp time */, 0 /* disable janitor */),
+		seenPendingBlocks:     make(map[[32]byte]bool),
+		blkRootToPendingAtts:  make(map[[32]byte][]ethpb.SignedAggregateAttAndProof),
+		dataColumnLogCh:       make(chan dataColumnLogEntry, 1000),
+		reconstructionRandGen: rand.NewGenerator(),
 	}
 
 	for _, opt := range opts {
@@ -192,6 +199,8 @@ func NewService(ctx context.Context, opts ...Option) *Service {
 			return nil
 		}
 	}
+	// Initialize signature channel with configured limit
+	r.signatureChan = make(chan *signatureVerifier, r.cfg.batchVerifierLimit)
 	// Correctly remove it from our seen pending block map.
 	// The eviction method always assumes that the mutex is held.
 	r.slotToPendingBlocks.OnEvicted(func(s string, i interface{}) {

beacon-chain/sync/subscriber.go

@@ -6,12 +6,14 @@ import (
 	"fmt"
 	"reflect"
 	"runtime/debug"
+	"slices"
 	"strings"
 	"time"
 
 	"github.com/OffchainLabs/prysm/v6/beacon-chain/cache"
 	"github.com/OffchainLabs/prysm/v6/beacon-chain/core/altair"
 	"github.com/OffchainLabs/prysm/v6/beacon-chain/core/helpers"
+	"github.com/OffchainLabs/prysm/v6/beacon-chain/core/peerdas"
 	"github.com/OffchainLabs/prysm/v6/beacon-chain/p2p"
 	"github.com/OffchainLabs/prysm/v6/beacon-chain/p2p/peers"
 	"github.com/OffchainLabs/prysm/v6/cmd/beacon-chain/flags"
@@ -188,14 +190,14 @@ func (s *Service) registerSubscribers(epoch primitives.Epoch, digest [4]byte) {
 		)
 	}
 
-	// New gossip topic in Fulu
+	// New gossip topic in Fulu.
 	if params.BeaconConfig().FuluForkEpoch <= epoch {
 		s.subscribeWithParameters(
 			p2p.DataColumnSubnetTopicFormat,
 			s.validateDataColumn,
-			func(context.Context, proto.Message) error { return nil },
+			s.dataColumnSubscriber,
 			digest,
-			func(primitives.Slot) []uint64 { return nil },
+			s.dataColumnSubnetIndices,
 			func(currentSlot primitives.Slot) []uint64 { return []uint64{} },
 		)
 	}
@@ -600,6 +602,19 @@ func (s *Service) enoughPeersAreConnected(subnetTopic string) bool {
 	return peersWithSubnetCount >= threshold
 }
 
+func (s *Service) dataColumnSubnetIndices(_ primitives.Slot) []uint64 {
+	nodeID := s.cfg.p2p.NodeID()
+	custodyGroupCount := s.cfg.custodyInfo.CustodyGroupSamplingSize(peerdas.Target)
+
+	nodeInfo, _, err := peerdas.Info(nodeID, custodyGroupCount)
+	if err != nil {
+		log.WithError(err).Error("Could not retrieve peer info")
+		return []uint64{}
+	}
+
+	return sliceFromMap(nodeInfo.DataColumnsSubnets, true /*sorted*/)
+}
+
 func (s *Service) persistentAndAggregatorSubnetIndices(currentSlot primitives.Slot) []uint64 {
 	if flags.Get().SubscribeToAllSubnets {
 		return sliceFromCount(params.BeaconConfig().AttestationSubnetCount)
@@ -727,3 +742,17 @@ func errorIsIgnored(err error) bool {
 	}
 	return false
 }
+
+// sliceFromMap returns a sorted list of keys from a map.
+func sliceFromMap(m map[uint64]bool, sorted ...bool) []uint64 {
+	result := make([]uint64, 0, len(m))
+	for k := range m {
+		result = append(result, k)
+	}
+
+	if len(sorted) > 0 && sorted[0] {
+		slices.Sort(result)
+	}
+
+	return result
+}

beacon-chain/sync/subscriber_data_column_sidecar.go

@@ -0,0 +1,54 @@
+package sync
+
+import (
+	"context"
+	"fmt"
+
+	"github.com/OffchainLabs/prysm/v6/beacon-chain/core/feed"
+	opfeed "github.com/OffchainLabs/prysm/v6/beacon-chain/core/feed/operation"
+	"github.com/OffchainLabs/prysm/v6/consensus-types/blocks"
+	"github.com/pkg/errors"
+	"google.golang.org/protobuf/proto"
+)
+
+func (s *Service) dataColumnSubscriber(ctx context.Context, msg proto.Message) error {
+	sidecar, ok := msg.(blocks.VerifiedRODataColumn)
+	if !ok {
+		return fmt.Errorf("message was not type blocks.VerifiedRODataColumn, type=%T", msg)
+	}
+
+	if err := s.receiveDataColumnSidecar(ctx, sidecar); err != nil {
+		return errors.Wrap(err, "receive data column")
+	}
+
+	slot := sidecar.Slot()
+	proposerIndex := sidecar.ProposerIndex()
+	root := sidecar.BlockRoot()
+
+	if err := s.reconstructSaveBroadcastDataColumnSidecars(ctx, slot, proposerIndex, root); err != nil {
+		return errors.Wrap(err, "reconstruct data columns")
+	}
+
+	return nil
+}
+
+func (s *Service) receiveDataColumnSidecar(ctx context.Context, sidecar blocks.VerifiedRODataColumn) error {
+	slot := sidecar.SignedBlockHeader.Header.Slot
+	proposerIndex := sidecar.SignedBlockHeader.Header.ProposerIndex
+	columnIndex := sidecar.Index
+
+	s.setSeenDataColumnIndex(slot, proposerIndex, columnIndex)
+
+	if err := s.cfg.chain.ReceiveDataColumn(sidecar); err != nil {
+		return errors.Wrap(err, "receive data column")
+	}
+
+	s.cfg.operationNotifier.OperationFeed().Send(&feed.Event{
+		Type: opfeed.DataColumnSidecarReceived,
+		Data: &opfeed.DataColumnSidecarReceivedData{
+			DataColumn: &sidecar,
+		},
+	})
+
+	return nil
+}

beacon-chain/sync/sync_test.go

@@ -15,10 +15,12 @@ func TestMain(m *testing.M) {
 
 	resetFlags := flags.Get()
 	flags.Init(&flags.GlobalFlags{
-		BlockBatchLimit:            64,
-		BlockBatchLimitBurstFactor: 10,
-		BlobBatchLimit:             32,
-		BlobBatchLimitBurstFactor:  2,
+		BlockBatchLimit:                 64,
+		BlockBatchLimitBurstFactor:      10,
+		BlobBatchLimit:                  32,
+		BlobBatchLimitBurstFactor:       2,
+		DataColumnBatchLimit:            4096,
+		DataColumnBatchLimitBurstFactor: 2,
 	})
 	defer func() {
 		flags.Init(resetFlags)

beacon-chain/verification/error.go

@@ -30,16 +30,16 @@ var (
 	ErrBlobIndexInvalid = errors.Join(ErrBlobInvalid, errors.New("incorrect blob sidecar index"))
 
 	// errFromFutureSlot means RequireSlotNotTooEarly failed.
-	errFromFutureSlot = errors.Join(ErrBlobInvalid, errors.New("slot is too far in the future"))
+	errFromFutureSlot = errors.New("slot is too far in the future")
 
 	// errSlotNotAfterFinalized means RequireSlotAboveFinalized failed.
-	errSlotNotAfterFinalized = errors.Join(ErrBlobInvalid, errors.New("slot <= finalized checkpoint"))
+	errSlotNotAfterFinalized = errors.New("slot <= finalized checkpoint")
 
 	// ErrInvalidProposerSignature means RequireValidProposerSignature failed.
 	ErrInvalidProposerSignature = errors.Join(ErrBlobInvalid, errors.New("proposer signature could not be verified"))
 
 	// errSidecarParentNotSeen means RequireSidecarParentSeen failed.
-	errSidecarParentNotSeen = errors.Join(ErrBlobInvalid, errors.New("parent root has not been seen"))
+	errSidecarParentNotSeen = errors.New("parent root has not been seen")
 
 	// errSidecarParentInvalid means RequireSidecarParentValid failed.
 	errSidecarParentInvalid = errors.Join(ErrBlobInvalid, errors.New("parent block is not valid"))

changelog/bastin_fix-lc-versioning.md

@@ -0,0 +1,3 @@
+### Fixed
+
+- Fixed the versioning bug for light client data types in the Beacon API.

changelog/bastin_put-lc-store-behind-flag.md

@@ -0,0 +1,3 @@
+### Changed
+
+- Put the initiation of LC Store behind the `enable-light-client` flag.

changelog/bastin_refactor-lc-bootstrap-tests.md

@@ -0,0 +1,3 @@
+### Ignored
+
+- Refactor light client bootstrap tests in the RPC package.

changelog/bastin_refactor-lc-kv-tests.md

@@ -0,0 +1,3 @@
+### Ignored
+
+- Refactor light client kv tests.

changelog/james-prysm_fix-duties-v2-assignment.md

@@ -0,0 +1,3 @@
+### Fixed
+
+- Fix panic on dutiesv2 when there is no committee assignment on the epoch

changelog/james-prysm_ssz-validator-block.md

@@ -0,0 +1,7 @@
+### Added
+
+- New ssz-only flag for validator client to enable calling rest apis in SSZ, starting with get block endpoint.
+
+### Changed
+
+- when REST api is enabled the get Block api defaults to requesting and receiving SSZ instead of JSON, JSON is the fallback.

changelog/manu-bootnodes.md

@@ -0,0 +1,2 @@
+### Fixed 
+- `--chain-config-file`: Do not use any more mainnet boot nodes.

changelog/manu-peerdas-beacon-api.md

@@ -0,0 +1,2 @@
+### Added 
+- Implement beacon API blob sidecar enpoint for Fulu.

changelog/manu-peerdas-columns-by-range-handler.md

@@ -0,0 +1,2 @@
+### Added 
+- Implement `dataColumnSidecarsByRangeRPCHandler`.

changelog/manu-peerdas-dataColumnSidecarByRootRPCHandler.md

@@ -0,0 +1,2 @@
+### Fixed 
+- Non deterministic output order of `dataColumnSidecarByRootRPCHandler`. 

changelog/manu-peerdas-get-blobs-V2.md

@@ -0,0 +1,3 @@
+### Added
+- Implement engine method `GetBlobsV2`
+- Implement execution `ReconstructDataColumnSidecars`, which reconstruct data column sidecars from data fetched from the execution layer.

changelog/manu-peerdas-metadata.md

@@ -0,0 +1,2 @@
+### Added 
+- PeerDAS: Implement the new Fulu Metadata.

changelog/manu-peerdas-reconstruction.md

@@ -0,0 +1,2 @@
+### Added 
+- PeerDAS: Implement reconstruction.

changelog/manu-peerdas-send-data-column-requests.md

@@ -0,0 +1,3 @@
+### Added 
+- Implement `SendDataColumnSidecarsByRangeRequest`.
+- Implement `SendDataColumnSidecarsByRootRequest`.

changelog/manu-peerdas-variou.md

@@ -0,0 +1,9 @@
+### Changed 
+- In `TopicFromMessage`: Do not assume anymore that all Fulu specific topic are V3 only.
+- `readChunkedDataColumnSidecar`: Add `validationFunctions` parameter and add tests.
+
+### Added
+- New `StatusV2` proto message.
+
+### Removed
+- Unused `DataColumnIdentifier` proto message.

changelog/tt_45.md

@@ -0,0 +1,3 @@
+### Changed
+
+- Increase mainnet DefaultBuilderGasLimit from 36M to 45M

changelog/tt_formula_mlk.md

@@ -0,0 +1,7 @@
+### Changed
+
+- Attest timely is now default. `attest-timely` flag is now deprecated.
+
+### Added
+
+- `disable-attest-timely` flag to disable attest timely.

changelog/tt_noodles.md

@@ -0,0 +1,7 @@
+### Added
+
+- new `--batch-verifier-limit` flag to configure max number of signatures to batch verify on gossip
+
+### Changed
+
+- default batch signature verification limit increased from 50 to 1000

changelog/tt_steak.md

@@ -0,0 +1,3 @@
+### Changed
+
+- Remove "invalid" from logs for incoming blob sidecar that is missing parent or out of range slot

cmd/beacon-chain/flags/base.go

@@ -212,11 +212,18 @@ var (
 		Usage: "The factor by which blob batch limit may increase on burst.",
 		Value: 3,
 	}
+	// DataColumnBatchLimit specifies the requested data column batch size.
 	DataColumnBatchLimit = &cli.IntFlag{
 		Name:  "data-column-batch-limit",
 		Usage: "The amount of data columns the local peer is bounded to request and respond to in a batch.",
 		Value: 4096,
 	}
+	// DataColumnBatchLimitBurstFactor specifies the factor by which data column batch size may increase.
+	DataColumnBatchLimitBurstFactor = &cli.IntFlag{
+		Name:  "data-column-batch-limit-burst-factor",
+		Usage: "The factor by which data column batch limit may increase on burst.",
+		Value: 2,
+	}
 	// DisableDebugRPCEndpoints disables the debug Beacon API namespace.
 	DisableDebugRPCEndpoints = &cli.BoolFlag{
 		Name:  "disable-debug-rpc-endpoints",
@@ -331,4 +338,10 @@ var (
 		Name:  "subscribe-all-data-subnets",
 		Usage: "Enable subscription to all data subnets.",
 	}
+	// BatchVerifierLimit sets the maximum number of signatures to batch verify at once.
+	BatchVerifierLimit = &cli.IntFlag{
+		Name:  "batch-verifier-limit",
+		Usage: "Maximum number of signatures to batch verify at once for beacon attestation p2p gossip.",
+		Value: 1000,
+	}
 )

cmd/beacon-chain/flags/config.go

@@ -8,16 +8,17 @@ import (
 // GlobalFlags specifies all the global flags for the
 // beacon node.
 type GlobalFlags struct {
-	SubscribeToAllSubnets      bool
-	SubscribeAllDataSubnets    bool
-	MinimumSyncPeers           int
-	MinimumPeersPerSubnet      int
-	MaxConcurrentDials         int
-	BlockBatchLimit            int
-	BlockBatchLimitBurstFactor int
-	BlobBatchLimit             int
-	DataColumnBatchLimit       int
-	BlobBatchLimitBurstFactor  int
+	SubscribeToAllSubnets           bool
+	SubscribeAllDataSubnets         bool
+	MinimumSyncPeers                int
+	MinimumPeersPerSubnet           int
+	MaxConcurrentDials              int
+	BlockBatchLimit                 int
+	BlockBatchLimitBurstFactor      int
+	BlobBatchLimit                  int
+	BlobBatchLimitBurstFactor       int
+	DataColumnBatchLimit            int
+	DataColumnBatchLimitBurstFactor int
 }
 
 var globalConfig *GlobalFlags
@@ -55,8 +56,10 @@ func ConfigureGlobalFlags(ctx *cli.Context) {
 	cfg.BlobBatchLimit = ctx.Int(BlobBatchLimit.Name)
 	cfg.BlobBatchLimitBurstFactor = ctx.Int(BlobBatchLimitBurstFactor.Name)
 	cfg.DataColumnBatchLimit = ctx.Int(DataColumnBatchLimit.Name)
+	cfg.DataColumnBatchLimitBurstFactor = ctx.Int(DataColumnBatchLimitBurstFactor.Name)
 	cfg.MinimumPeersPerSubnet = ctx.Int(MinPeersPerSubnet.Name)
 	cfg.MaxConcurrentDials = ctx.Int(MaxConcurrentDials.Name)
+
 	configureMinimumPeers(ctx, cfg)
 
 	Init(cfg)

cmd/beacon-chain/main.go

@@ -149,6 +149,7 @@ var appFlags = []cli.Flag{
 	bflags.BackfillBatchSize,
 	bflags.BackfillWorkerCount,
 	bflags.BackfillOldestSlot,
+	flags.BatchVerifierLimit,
 }
 
 func init() {

cmd/beacon-chain/usage.go

@@ -72,6 +72,7 @@ var appHelpFlagGroups = []flagGroup{
 			flags.NetworkID,
 			flags.RPCHost,
 			flags.RPCPort,
+			flags.BatchVerifierLimit,
 		},
 	},
 	{

config/features/config.go

@@ -52,6 +52,7 @@ type Flags struct {
 	EnableExperimentalAttestationPool   bool // EnableExperimentalAttestationPool enables an experimental attestation pool design.
 	EnableDutiesV2                      bool // EnableDutiesV2 sets validator client to use the get Duties V2 endpoint
 	EnableWeb                           bool // EnableWeb enables the webui on the validator client
+	SSZOnly                             bool // SSZOnly forces the validator client to use SSZ for communication with the beacon node when REST mode is enabled (useful for debugging)
 	// Logging related toggles.
 	DisableGRPCConnectionLogs bool // Disables logging when a new grpc client has connected.
 	EnableFullSSZDataLogging  bool // Enables logging for full ssz data on rejected gossip messages
@@ -155,7 +156,8 @@ func configureTestnet(ctx *cli.Context) error {
 		params.UseHoodiNetworkConfig()
 	} else {
 		if ctx.IsSet(cmd.ChainConfigFileFlag.Name) {
-			log.Warn("Running on custom Ethereum network specified in a chain configuration yaml file")
+			log.Warning("Running on custom Ethereum network specified in a chain configuration YAML file")
+			params.UseCustomNetworkConfig()
 		} else {
 			log.Info("Running on Ethereum Mainnet")
 		}
@@ -167,11 +169,11 @@ func configureTestnet(ctx *cli.Context) error {
 }
 
 // Insert feature flags within the function to be enabled for Sepolia testnet.
-func applySepoliaFeatureFlags(ctx *cli.Context) {
+func applySepoliaFeatureFlags(_ *cli.Context) {
 }
 
 // Insert feature flags within the function to be enabled for Holesky testnet.
-func applyHoleskyFeatureFlags(ctx *cli.Context) {
+func applyHoleskyFeatureFlags(_ *cli.Context) {
 }
 
 // ConfigureBeaconChain sets the global config based
@@ -316,9 +318,10 @@ func ConfigureValidator(ctx *cli.Context) error {
 		logEnabled(writeWalletPasswordOnWebOnboarding)
 		cfg.WriteWalletPasswordOnWebOnboarding = true
 	}
-	if ctx.Bool(attestTimely.Name) {
-		logEnabled(attestTimely)
-		cfg.AttestTimely = true
+	cfg.AttestTimely = true
+	if ctx.Bool(disableAttestTimely.Name) {
+		logEnabled(disableAttestTimely)
+		cfg.AttestTimely = false
 	}
 	if ctx.Bool(enableSlashingProtectionPruning.Name) {
 		logEnabled(enableSlashingProtectionPruning)
@@ -344,6 +347,11 @@ func ConfigureValidator(ctx *cli.Context) error {
 		logEnabled(EnableWebFlag)
 		cfg.EnableWeb = true
 	}
+	if ctx.Bool(SSZOnly.Name) {
+		logEnabled(SSZOnly)
+		cfg.SSZOnly = true
+	}
+
 	cfg.KeystoreImportDebounceInterval = ctx.Duration(dynamicKeyReloadDebounceInterval.Name)
 	Init(cfg)
 	return nil

config/features/deprecated_flags.go

@@ -98,6 +98,11 @@ var (
 		Usage:  deprecatedUsage,
 		Hidden: true,
 	}
+	deprecatedAttestTimely = &cli.BoolFlag{
+		Name:   "attest-timely",
+		Usage:  deprecatedUsage,
+		Hidden: true,
+	}
 )
 
 // Deprecated flags for both the beacon node and validator client.
@@ -118,6 +123,7 @@ var deprecatedFlags = []cli.Flag{
 	deprecatedEnableCommitteeAwarePacking,
 	deprecatedInteropGenesisTimeFlag,
 	deprecatedEnableQuic,
+	deprecatedAttestTimely,
 }
 
 var upcomingDeprecation = []cli.Flag{

config/features/flags.go

@@ -91,9 +91,9 @@ var (
 		Name:  "disable-broadcast-slashings",
 		Usage: "Disables broadcasting slashings submitted to the beacon node.",
 	}
-	attestTimely = &cli.BoolFlag{
-		Name:  "attest-timely",
-		Usage: "Fixes validator can attest timely after current block processes. See #8185 for more details.",
+	disableAttestTimely = &cli.BoolFlag{
+		Name:  "disable-attest-timely",
+		Usage: "Disable validator attesting timely after current block processes. See #8185 for more details.",
 	}
 	enableSlashingProtectionPruning = &cli.BoolFlag{
 		Name:  "enable-slashing-protection-history-pruning",
@@ -201,6 +201,12 @@ var (
 		Usage: "(Work in progress): Enables the web portal for the validator client.",
 		Value: false,
 	}
+
+	// SSZOnly forces the validator client to use SSZ for communication with the beacon node when REST mode is enabled
+	SSZOnly = &cli.BoolFlag{
+		Name:  "ssz-only",
+		Usage: "(debug): Forces the validator client to use SSZ for communication with the beacon node when REST mode is enabled",
+	}
 )
 
 // devModeFlags holds list of flags that are set when development mode is on.
@@ -216,13 +222,14 @@ var ValidatorFlags = append(deprecatedFlags, []cli.Flag{
 	HoodiTestnet,
 	Mainnet,
 	dynamicKeyReloadDebounceInterval,
-	attestTimely,
+	disableAttestTimely,
 	enableSlashingProtectionPruning,
 	EnableMinimalSlashingProtection,
 	enableDoppelGangerProtection,
 	EnableBeaconRESTApi,
 	EnableDutiesV2,
 	EnableWebFlag,
+	SSZOnly,
 }...)
 
 // E2EValidatorFlags contains a list of the validator feature flags to be tested in E2E.

config/params/BUILD.bazel

@@ -14,6 +14,7 @@ go_library(
         "mainnet_config.go",
         "minimal_config.go",
         "network_config.go",
+        "testnet_custom_network_config.go",
         "testnet_e2e_config.go",
         "testnet_holesky_config.go",
         "testnet_hoodi_config.go",

config/params/mainnet_config.go

@@ -268,7 +268,7 @@ var mainnetBeaconConfig = &BeaconChainConfig{
 	BytesPerLogsBloom:                256,
 	MaxExtraDataBytes:                32,
 	EthBurnAddressHex:                "0x0000000000000000000000000000000000000000",
-	DefaultBuilderGasLimit:           uint64(36000000),
+	DefaultBuilderGasLimit:           uint64(45000000),
 
 	// Mevboost circuit breaker
 	MaxBuilderConsecutiveMissedSlots: 3,

config/params/testnet_custom_network_config.go

@@ -0,0 +1,9 @@
+package params
+
+func UseCustomNetworkConfig() {
+	cfg := BeaconNetworkConfig().Copy()
+	cfg.ContractDeploymentBlock = 0
+	cfg.BootstrapNodes = []string{}
+
+	OverrideBeaconNetworkConfig(cfg)
+}

config/proposer/loader/testdata/good-prepare-beacon-proposer-config-multiple.json

@@ -4,7 +4,7 @@
       "fee_recipient": "0x50155530FCE8a85ec7055A5F8b2bE214B3DaeFd3",
       "builder": {
         "enabled": true,
-        "gas_limit": "36000000"
+        "gas_limit": "45000000"
       }
     },
     "0xb057816155ad77931185101128655c0191bd0214c201ca48ed887f6c4c6adf334070efcd75140eada5ac83a92506dd7b": {

config/proposer/loader/testdata/good-prepare-beacon-proposer-config.yaml

@@ -9,4 +9,4 @@ default_config:
   fee_recipient: '0x6e35733c5af9B61374A128e6F85f553aF09ff89A'
   builder:
     enabled: false
-    gas_limit: '36000000'
+    gas_limit: '45000000'

consensus-types/blocks/execution.go

@@ -2,7 +2,6 @@ package blocks
 
 import (
 	"bytes"
-	"errors"
 
 	fieldparams "github.com/OffchainLabs/prysm/v6/config/fieldparams"
 	consensus_types "github.com/OffchainLabs/prysm/v6/consensus-types"
@@ -10,6 +9,7 @@ import (
 	"github.com/OffchainLabs/prysm/v6/encoding/bytesutil"
 	"github.com/OffchainLabs/prysm/v6/encoding/ssz"
 	enginev1 "github.com/OffchainLabs/prysm/v6/proto/engine/v1"
+	"github.com/pkg/errors"
 	fastssz "github.com/prysmaticlabs/fastssz"
 	"google.golang.org/protobuf/proto"
 )
@@ -40,8 +40,10 @@ func NewWrappedExecutionData(v proto.Message) (interfaces.ExecutionData, error)
 	case *enginev1.ExecutionBundleElectra:
 		// note: no payload changes in electra so using deneb
 		return WrappedExecutionPayloadDeneb(pbStruct.Payload)
+	case *enginev1.ExecutionBundleFulu:
+		return WrappedExecutionPayloadDeneb(pbStruct.Payload)
 	default:
-		return nil, ErrUnsupportedVersion
+		return nil, errors.Wrapf(ErrUnsupportedVersion, "type %T", pbStruct)
 	}
 }
 

consensus-types/blocks/get_payload.go

@@ -5,6 +5,7 @@ import (
 	"github.com/OffchainLabs/prysm/v6/consensus-types/interfaces"
 	"github.com/OffchainLabs/prysm/v6/consensus-types/primitives"
 	pb "github.com/OffchainLabs/prysm/v6/proto/engine/v1"
+	"github.com/pkg/errors"
 	"google.golang.org/protobuf/proto"
 )
 
@@ -12,7 +13,7 @@ import (
 // GetPayloadResponseV(1|2|3|4) value.
 type GetPayloadResponse struct {
 	ExecutionData   interfaces.ExecutionData
-	BlobsBundle     *pb.BlobsBundle
+	BlobsBundler    pb.BlobsBundler
 	OverrideBuilder bool
 	// todo: should we convert this to Gwei up front?
 	Bid               primitives.Wei
@@ -24,6 +25,10 @@ type bundleGetter interface {
 	GetBlobsBundle() *pb.BlobsBundle
 }
 
+type bundleV2Getter interface {
+	GetBlobsBundle() *pb.BlobsBundleV2
+}
+
 // bidValueGetter is an interface satisfied by get payload responses that have a bid value.
 type bidValueGetter interface {
 	GetValue() []byte
@@ -41,10 +46,13 @@ func NewGetPayloadResponse(msg proto.Message) (*GetPayloadResponse, error) {
 	r := &GetPayloadResponse{}
 	bundleGetter, hasBundle := msg.(bundleGetter)
 	if hasBundle {
-		r.BlobsBundle = bundleGetter.GetBlobsBundle()
+		r.BlobsBundler = bundleGetter.GetBlobsBundle()
+	}
+	bundleV2Getter, hasBundle := msg.(bundleV2Getter)
+	if hasBundle {
+		r.BlobsBundler = bundleV2Getter.GetBlobsBundle()
 	}
 	bidValueGetter, hasBid := msg.(bidValueGetter)
-	executionRequestsGetter, hasExecutionRequests := msg.(executionRequestsGetter)
 	wei := primitives.ZeroWei()
 	if hasBid {
 		// The protobuf types that engine api responses unmarshal into store their values in little endian form.
@@ -60,13 +68,15 @@ func NewGetPayloadResponse(msg proto.Message) (*GetPayloadResponse, error) {
 	}
 	ed, err := NewWrappedExecutionData(msg)
 	if err != nil {
-		return nil, err
+		return nil, errors.Wrap(err, "new wrapped execution data")
 	}
 	r.ExecutionData = ed
+
+	executionRequestsGetter, hasExecutionRequests := msg.(executionRequestsGetter)
 	if hasExecutionRequests {
 		requests, err := executionRequestsGetter.GetDecodedExecutionRequests(params.BeaconConfig().ExecutionRequestLimits())
 		if err != nil {
-			return nil, err
+			return nil, errors.Wrap(err, "get decoded execution requests")
 		}
 		r.ExecutionRequests = requests
 	}

consensus-types/light-client/bootstrap.go

@@ -8,6 +8,7 @@ import (
 	"github.com/OffchainLabs/prysm/v6/consensus-types/interfaces"
 	pb "github.com/OffchainLabs/prysm/v6/proto/prysm/v1alpha1"
 	"github.com/OffchainLabs/prysm/v6/runtime/version"
+	"github.com/OffchainLabs/prysm/v6/time/slots"
 	"google.golang.org/protobuf/proto"
 )
 
@@ -83,7 +84,7 @@ func (h *bootstrapAltair) SizeSSZ() int {
 }
 
 func (h *bootstrapAltair) Version() int {
-	return version.Altair
+	return slots.ToForkVersion(h.header.Beacon().Slot)
 }
 
 func (h *bootstrapAltair) Proto() proto.Message {
@@ -188,7 +189,7 @@ func (h *bootstrapCapella) SizeSSZ() int {
 }
 
 func (h *bootstrapCapella) Version() int {
-	return version.Capella
+	return slots.ToForkVersion(h.header.Beacon().Slot)
 }
 
 func (h *bootstrapCapella) Proto() proto.Message {
@@ -293,7 +294,7 @@ func (h *bootstrapDeneb) SizeSSZ() int {
 }
 
 func (h *bootstrapDeneb) Version() int {
-	return version.Deneb
+	return slots.ToForkVersion(h.header.Beacon().Slot)
 }
 
 func (h *bootstrapDeneb) Proto() proto.Message {
@@ -398,7 +399,7 @@ func (h *bootstrapElectra) SizeSSZ() int {
 }
 
 func (h *bootstrapElectra) Version() int {
-	return version.Electra
+	return slots.ToForkVersion(h.header.Beacon().Slot)
 }
 
 func (h *bootstrapElectra) Proto() proto.Message {

consensus-types/light-client/finality_update.go

@@ -8,7 +8,7 @@ import (
 	"github.com/OffchainLabs/prysm/v6/consensus-types/interfaces"
 	"github.com/OffchainLabs/prysm/v6/consensus-types/primitives"
 	pb "github.com/OffchainLabs/prysm/v6/proto/prysm/v1alpha1"
-	"github.com/OffchainLabs/prysm/v6/runtime/version"
+	"github.com/OffchainLabs/prysm/v6/time/slots"
 	"google.golang.org/protobuf/proto"
 )
 
@@ -174,7 +174,7 @@ func (u *finalityUpdateAltair) Proto() proto.Message {
 }
 
 func (u *finalityUpdateAltair) Version() int {
-	return version.Altair
+	return slots.ToForkVersion(u.attestedHeader.Beacon().Slot)
 }
 
 func (u *finalityUpdateAltair) AttestedHeader() interfaces.LightClientHeader {
@@ -286,7 +286,7 @@ func (u *finalityUpdateCapella) Proto() proto.Message {
 }
 
 func (u *finalityUpdateCapella) Version() int {
-	return version.Capella
+	return slots.ToForkVersion(u.attestedHeader.Beacon().Slot)
 }
 
 func (u *finalityUpdateCapella) AttestedHeader() interfaces.LightClientHeader {
@@ -398,7 +398,7 @@ func (u *finalityUpdateDeneb) Proto() proto.Message {
 }
 
 func (u *finalityUpdateDeneb) Version() int {
-	return version.Deneb
+	return slots.ToForkVersion(u.attestedHeader.Beacon().Slot)
 }
 
 func (u *finalityUpdateDeneb) AttestedHeader() interfaces.LightClientHeader {
@@ -511,7 +511,7 @@ func (u *finalityUpdateElectra) Proto() proto.Message {
 }
 
 func (u *finalityUpdateElectra) Version() int {
-	return version.Electra
+	return slots.ToForkVersion(u.attestedHeader.Beacon().Slot)
 }
 
 func (u *finalityUpdateElectra) AttestedHeader() interfaces.LightClientHeader {

consensus-types/light-client/optimistic_update.go

@@ -7,7 +7,7 @@ import (
 	"github.com/OffchainLabs/prysm/v6/consensus-types/interfaces"
 	"github.com/OffchainLabs/prysm/v6/consensus-types/primitives"
 	pb "github.com/OffchainLabs/prysm/v6/proto/prysm/v1alpha1"
-	"github.com/OffchainLabs/prysm/v6/runtime/version"
+	"github.com/OffchainLabs/prysm/v6/time/slots"
 	"google.golang.org/protobuf/proto"
 )
 
@@ -139,7 +139,7 @@ func (u *optimisticUpdateAltair) Proto() proto.Message {
 }
 
 func (u *optimisticUpdateAltair) Version() int {
-	return version.Altair
+	return slots.ToForkVersion(u.attestedHeader.Beacon().Slot)
 }
 
 func (u *optimisticUpdateAltair) AttestedHeader() interfaces.LightClientHeader {
@@ -223,7 +223,7 @@ func (u *optimisticUpdateCapella) Proto() proto.Message {
 }
 
 func (u *optimisticUpdateCapella) Version() int {
-	return version.Capella
+	return slots.ToForkVersion(u.attestedHeader.Beacon().Slot)
 }
 
 func (u *optimisticUpdateCapella) AttestedHeader() interfaces.LightClientHeader {
@@ -307,7 +307,7 @@ func (u *optimisticUpdateDeneb) Proto() proto.Message {
 }
 
 func (u *optimisticUpdateDeneb) Version() int {
-	return version.Deneb
+	return slots.ToForkVersion(u.attestedHeader.Beacon().Slot)
 }
 
 func (u *optimisticUpdateDeneb) AttestedHeader() interfaces.LightClientHeader {

consensus-types/light-client/update.go

@@ -9,6 +9,7 @@ import (
 	"github.com/OffchainLabs/prysm/v6/consensus-types/primitives"
 	pb "github.com/OffchainLabs/prysm/v6/proto/prysm/v1alpha1"
 	"github.com/OffchainLabs/prysm/v6/runtime/version"
+	"github.com/OffchainLabs/prysm/v6/time/slots"
 	"google.golang.org/protobuf/proto"
 )
 
@@ -105,7 +106,7 @@ func (u *updateAltair) Proto() proto.Message {
 }
 
 func (u *updateAltair) Version() int {
-	return version.Altair
+	return slots.ToForkVersion(u.attestedHeader.Beacon().Slot)
 }
 
 func (u *updateAltair) AttestedHeader() interfaces.LightClientHeader {
@@ -272,7 +273,7 @@ func (u *updateCapella) Proto() proto.Message {
 }
 
 func (u *updateCapella) Version() int {
-	return version.Capella
+	return slots.ToForkVersion(u.attestedHeader.Beacon().Slot)
 }
 
 func (u *updateCapella) AttestedHeader() interfaces.LightClientHeader {
@@ -439,7 +440,7 @@ func (u *updateDeneb) Proto() proto.Message {
 }
 
 func (u *updateDeneb) Version() int {
-	return version.Deneb
+	return slots.ToForkVersion(u.attestedHeader.Beacon().Slot)
 }
 
 func (u *updateDeneb) AttestedHeader() interfaces.LightClientHeader {
@@ -607,7 +608,7 @@ func (u *updateElectra) Proto() proto.Message {
 }
 
 func (u *updateElectra) Version() int {
-	return version.Electra
+	return slots.ToForkVersion(u.attestedHeader.Beacon().Slot)
 }
 
 func (u *updateElectra) AttestedHeader() interfaces.LightClientHeader {

proto/prysm/v1alpha1/BUILD.bazel

@@ -2,14 +2,13 @@
 # Common
 ##############################################################################
 
-load("@rules_proto//proto:defs.bzl", "proto_library")
-
 ##############################################################################
 # Go
 ##############################################################################
 # gazelle:ignore
 load("@io_bazel_rules_go//go:def.bzl", "go_library", "go_test")
 load("@io_bazel_rules_go//proto:def.bzl", "go_proto_library")
+load("@rules_proto//proto:defs.bzl", "proto_library")
 load("//proto:ssz_proto_library.bzl", "ssz_proto_files")
 load("//tools:ssz.bzl", "SSZ_DEPS", "ssz_gen_marshal")
 
@@ -189,6 +188,7 @@ ssz_fulu_objs = [
     "DataColumnIdentifier",
     "DataColumnsByRootIdentifier",
     "DataColumnSidecar",
+    "StatusV2",
     "SignedBeaconBlockContentsFulu",
     "SignedBeaconBlockFulu",
     "SignedBlindedBeaconBlockFulu",
@@ -359,15 +359,17 @@ go_library(
     importpath = "github.com/OffchainLabs/prysm/v6/proto/prysm/v1alpha1",
     visibility = ["//visibility:public"],
     deps = SSZ_DEPS + [
+        "//consensus-types/primitives:go_default_library",
         "//encoding/bytesutil:go_default_library",
         "//math:go_default_library",
         "//proto/engine/v1:go_default_library",
         "//proto/eth/ext:go_default_library",
         "//runtime/version:go_default_library",
-        "//consensus-types/primitives:go_default_library",
-        "@com_github_pkg_errors//:go_default_library",
         "@com_github_golang_protobuf//proto:go_default_library",
+        "@com_github_pkg_errors//:go_default_library",
         "@com_github_prysmaticlabs_go_bitfield//:go_default_library",  # keep
+        "@com_github_sirupsen_logrus//:go_default_library",
+        "@com_github_sirupsen_logrus//hooks/test:go_default_library",
         "@googleapis//google/api:annotations_go_proto",
         "@io_bazel_rules_go//proto/wkt:descriptor_go_proto",
         "@io_bazel_rules_go//proto/wkt:empty_go_proto",
@@ -382,8 +384,6 @@ go_library(
         "@org_golang_google_protobuf//runtime/protoimpl:go_default_library",
         "@org_golang_google_protobuf//types/descriptorpb:go_default_library",
         "@org_golang_google_protobuf//types/known/emptypb:go_default_library",
-        "@com_github_sirupsen_logrus//:go_default_library",
-        "@com_github_sirupsen_logrus//hooks/test:go_default_library",
     ],
 )
 

proto/prysm/v1alpha1/beacon_block.go

@@ -5,6 +5,12 @@ import (
 	enginev1 "github.com/OffchainLabs/prysm/v6/proto/engine/v1"
 )
 
+// GenericConverter defines any struct that can be converted to a generic beacon block.
+// We assume all your versioned block structs implement this method.
+type GenericConverter interface {
+	ToGeneric() (*GenericBeaconBlock, error)
+}
+
 // ----------------------------------------------------------------------------
 // Phase 0
 // ----------------------------------------------------------------------------

proto/prysm/v1alpha1/data_columns.pb.go

@@ -109,61 +109,6 @@ func (x *DataColumnSidecar) GetKzgCommitmentsInclusionProof() [][]byte {
 	return nil
 }
 
-type DataColumnIdentifier struct {
-	state         protoimpl.MessageState
-	sizeCache     protoimpl.SizeCache
-	unknownFields protoimpl.UnknownFields
-
-	BlockRoot []byte `protobuf:"bytes,1,opt,name=block_root,json=blockRoot,proto3" json:"block_root,omitempty" ssz-size:"32"`
-	Index     uint64 `protobuf:"varint,2,opt,name=index,proto3" json:"index,omitempty"`
-}
-
-func (x *DataColumnIdentifier) Reset() {
-	*x = DataColumnIdentifier{}
-	if protoimpl.UnsafeEnabled {
-		mi := &file_proto_prysm_v1alpha1_data_columns_proto_msgTypes[1]
-		ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x))
-		ms.StoreMessageInfo(mi)
-	}
-}
-
-func (x *DataColumnIdentifier) String() string {
-	return protoimpl.X.MessageStringOf(x)
-}
-
-func (*DataColumnIdentifier) ProtoMessage() {}
-
-func (x *DataColumnIdentifier) ProtoReflect() protoreflect.Message {
-	mi := &file_proto_prysm_v1alpha1_data_columns_proto_msgTypes[1]
-	if protoimpl.UnsafeEnabled && x != nil {
-		ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x))
-		if ms.LoadMessageInfo() == nil {
-			ms.StoreMessageInfo(mi)
-		}
-		return ms
-	}
-	return mi.MessageOf(x)
-}
-
-// Deprecated: Use DataColumnIdentifier.ProtoReflect.Descriptor instead.
-func (*DataColumnIdentifier) Descriptor() ([]byte, []int) {
-	return file_proto_prysm_v1alpha1_data_columns_proto_rawDescGZIP(), []int{1}
-}
-
-func (x *DataColumnIdentifier) GetBlockRoot() []byte {
-	if x != nil {
-		return x.BlockRoot
-	}
-	return nil
-}
-
-func (x *DataColumnIdentifier) GetIndex() uint64 {
-	if x != nil {
-		return x.Index
-	}
-	return 0
-}
-
 type DataColumnsByRootIdentifier struct {
 	state         protoimpl.MessageState
 	sizeCache     protoimpl.SizeCache
@@ -176,7 +121,7 @@ type DataColumnsByRootIdentifier struct {
 func (x *DataColumnsByRootIdentifier) Reset() {
 	*x = DataColumnsByRootIdentifier{}
 	if protoimpl.UnsafeEnabled {
-		mi := &file_proto_prysm_v1alpha1_data_columns_proto_msgTypes[2]
+		mi := &file_proto_prysm_v1alpha1_data_columns_proto_msgTypes[1]
 		ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x))
 		ms.StoreMessageInfo(mi)
 	}
@@ -189,7 +134,7 @@ func (x *DataColumnsByRootIdentifier) String() string {
 func (*DataColumnsByRootIdentifier) ProtoMessage() {}
 
 func (x *DataColumnsByRootIdentifier) ProtoReflect() protoreflect.Message {
-	mi := &file_proto_prysm_v1alpha1_data_columns_proto_msgTypes[2]
+	mi := &file_proto_prysm_v1alpha1_data_columns_proto_msgTypes[1]
 	if protoimpl.UnsafeEnabled && x != nil {
 		ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x))
 		if ms.LoadMessageInfo() == nil {
@@ -202,7 +147,7 @@ func (x *DataColumnsByRootIdentifier) ProtoReflect() protoreflect.Message {
 
 // Deprecated: Use DataColumnsByRootIdentifier.ProtoReflect.Descriptor instead.
 func (*DataColumnsByRootIdentifier) Descriptor() ([]byte, []int) {
-	return file_proto_prysm_v1alpha1_data_columns_proto_rawDescGZIP(), []int{2}
+	return file_proto_prysm_v1alpha1_data_columns_proto_rawDescGZIP(), []int{1}
 }
 
 func (x *DataColumnsByRootIdentifier) GetBlockRoot() []byte {
@@ -253,29 +198,24 @@ var file_proto_prysm_v1alpha1_data_columns_proto_rawDesc = []byte{
 	0x63, 0x6c, 0x75, 0x73, 0x69, 0x6f, 0x6e, 0x5f, 0x70, 0x72, 0x6f, 0x6f, 0x66, 0x18, 0x06, 0x20,
 	0x03, 0x28, 0x0c, 0x42, 0x08, 0x8a, 0xb5, 0x18, 0x04, 0x34, 0x2c, 0x33, 0x32, 0x52, 0x1c, 0x6b,
 	0x7a, 0x67, 0x43, 0x6f, 0x6d, 0x6d, 0x69, 0x74, 0x6d, 0x65, 0x6e, 0x74, 0x73, 0x49, 0x6e, 0x63,
-	0x6c, 0x75, 0x73, 0x69, 0x6f, 0x6e, 0x50, 0x72, 0x6f, 0x6f, 0x66, 0x22, 0x53, 0x0a, 0x14, 0x44,
-	0x61, 0x74, 0x61, 0x43, 0x6f, 0x6c, 0x75, 0x6d, 0x6e, 0x49, 0x64, 0x65, 0x6e, 0x74, 0x69, 0x66,
-	0x69, 0x65, 0x72, 0x12, 0x25, 0x0a, 0x0a, 0x62, 0x6c, 0x6f, 0x63, 0x6b, 0x5f, 0x72, 0x6f, 0x6f,
-	0x74, 0x18, 0x01, 0x20, 0x01, 0x28, 0x0c, 0x42, 0x06, 0x8a, 0xb5, 0x18, 0x02, 0x33, 0x32, 0x52,
-	0x09, 0x62, 0x6c, 0x6f, 0x63, 0x6b, 0x52, 0x6f, 0x6f, 0x74, 0x12, 0x14, 0x0a, 0x05, 0x69, 0x6e,
-	0x64, 0x65, 0x78, 0x18, 0x02, 0x20, 0x01, 0x28, 0x04, 0x52, 0x05, 0x69, 0x6e, 0x64, 0x65, 0x78,
-	0x22, 0x67, 0x0a, 0x1b, 0x44, 0x61, 0x74, 0x61, 0x43, 0x6f, 0x6c, 0x75, 0x6d, 0x6e, 0x73, 0x42,
-	0x79, 0x52, 0x6f, 0x6f, 0x74, 0x49, 0x64, 0x65, 0x6e, 0x74, 0x69, 0x66, 0x69, 0x65, 0x72, 0x12,
-	0x25, 0x0a, 0x0a, 0x62, 0x6c, 0x6f, 0x63, 0x6b, 0x5f, 0x72, 0x6f, 0x6f, 0x74, 0x18, 0x01, 0x20,
-	0x01, 0x28, 0x0c, 0x42, 0x06, 0x8a, 0xb5, 0x18, 0x02, 0x33, 0x32, 0x52, 0x09, 0x62, 0x6c, 0x6f,
-	0x63, 0x6b, 0x52, 0x6f, 0x6f, 0x74, 0x12, 0x21, 0x0a, 0x07, 0x63, 0x6f, 0x6c, 0x75, 0x6d, 0x6e,
-	0x73, 0x18, 0x02, 0x20, 0x03, 0x28, 0x04, 0x42, 0x07, 0x92, 0xb5, 0x18, 0x03, 0x31, 0x32, 0x38,
-	0x52, 0x07, 0x63, 0x6f, 0x6c, 0x75, 0x6d, 0x6e, 0x73, 0x42, 0x9a, 0x01, 0x0a, 0x19, 0x6f, 0x72,
-	0x67, 0x2e, 0x65, 0x74, 0x68, 0x65, 0x72, 0x65, 0x75, 0x6d, 0x2e, 0x65, 0x74, 0x68, 0x2e, 0x76,
-	0x31, 0x61, 0x6c, 0x70, 0x68, 0x61, 0x31, 0x42, 0x10, 0x44, 0x61, 0x74, 0x61, 0x43, 0x6f, 0x6c,
-	0x75, 0x6d, 0x6e, 0x73, 0x50, 0x72, 0x6f, 0x74, 0x6f, 0x50, 0x01, 0x5a, 0x39, 0x67, 0x69, 0x74,
-	0x68, 0x75, 0x62, 0x2e, 0x63, 0x6f, 0x6d, 0x2f, 0x4f, 0x66, 0x66, 0x63, 0x68, 0x61, 0x69, 0x6e,
-	0x4c, 0x61, 0x62, 0x73, 0x2f, 0x70, 0x72, 0x79, 0x73, 0x6d, 0x2f, 0x76, 0x36, 0x2f, 0x70, 0x72,
-	0x6f, 0x74, 0x6f, 0x2f, 0x70, 0x72, 0x79, 0x73, 0x6d, 0x2f, 0x76, 0x31, 0x61, 0x6c, 0x70, 0x68,
-	0x61, 0x31, 0x3b, 0x65, 0x74, 0x68, 0xaa, 0x02, 0x15, 0x45, 0x74, 0x68, 0x65, 0x72, 0x65, 0x75,
-	0x6d, 0x2e, 0x45, 0x74, 0x68, 0x2e, 0x76, 0x31, 0x61, 0x6c, 0x70, 0x68, 0x61, 0x31, 0xca, 0x02,
-	0x15, 0x45, 0x74, 0x68, 0x65, 0x72, 0x65, 0x75, 0x6d, 0x5c, 0x45, 0x74, 0x68, 0x5c, 0x76, 0x31,
-	0x61, 0x6c, 0x70, 0x68, 0x61, 0x31, 0x62, 0x06, 0x70, 0x72, 0x6f, 0x74, 0x6f, 0x33,
+	0x6c, 0x75, 0x73, 0x69, 0x6f, 0x6e, 0x50, 0x72, 0x6f, 0x6f, 0x66, 0x22, 0x67, 0x0a, 0x1b, 0x44,
+	0x61, 0x74, 0x61, 0x43, 0x6f, 0x6c, 0x75, 0x6d, 0x6e, 0x73, 0x42, 0x79, 0x52, 0x6f, 0x6f, 0x74,
+	0x49, 0x64, 0x65, 0x6e, 0x74, 0x69, 0x66, 0x69, 0x65, 0x72, 0x12, 0x25, 0x0a, 0x0a, 0x62, 0x6c,
+	0x6f, 0x63, 0x6b, 0x5f, 0x72, 0x6f, 0x6f, 0x74, 0x18, 0x01, 0x20, 0x01, 0x28, 0x0c, 0x42, 0x06,
+	0x8a, 0xb5, 0x18, 0x02, 0x33, 0x32, 0x52, 0x09, 0x62, 0x6c, 0x6f, 0x63, 0x6b, 0x52, 0x6f, 0x6f,
+	0x74, 0x12, 0x21, 0x0a, 0x07, 0x63, 0x6f, 0x6c, 0x75, 0x6d, 0x6e, 0x73, 0x18, 0x02, 0x20, 0x03,
+	0x28, 0x04, 0x42, 0x07, 0x92, 0xb5, 0x18, 0x03, 0x31, 0x32, 0x38, 0x52, 0x07, 0x63, 0x6f, 0x6c,
+	0x75, 0x6d, 0x6e, 0x73, 0x42, 0x9a, 0x01, 0x0a, 0x19, 0x6f, 0x72, 0x67, 0x2e, 0x65, 0x74, 0x68,
+	0x65, 0x72, 0x65, 0x75, 0x6d, 0x2e, 0x65, 0x74, 0x68, 0x2e, 0x76, 0x31, 0x61, 0x6c, 0x70, 0x68,
+	0x61, 0x31, 0x42, 0x10, 0x44, 0x61, 0x74, 0x61, 0x43, 0x6f, 0x6c, 0x75, 0x6d, 0x6e, 0x73, 0x50,
+	0x72, 0x6f, 0x74, 0x6f, 0x50, 0x01, 0x5a, 0x39, 0x67, 0x69, 0x74, 0x68, 0x75, 0x62, 0x2e, 0x63,
+	0x6f, 0x6d, 0x2f, 0x4f, 0x66, 0x66, 0x63, 0x68, 0x61, 0x69, 0x6e, 0x4c, 0x61, 0x62, 0x73, 0x2f,
+	0x70, 0x72, 0x79, 0x73, 0x6d, 0x2f, 0x76, 0x36, 0x2f, 0x70, 0x72, 0x6f, 0x74, 0x6f, 0x2f, 0x70,
+	0x72, 0x79, 0x73, 0x6d, 0x2f, 0x76, 0x31, 0x61, 0x6c, 0x70, 0x68, 0x61, 0x31, 0x3b, 0x65, 0x74,
+	0x68, 0xaa, 0x02, 0x15, 0x45, 0x74, 0x68, 0x65, 0x72, 0x65, 0x75, 0x6d, 0x2e, 0x45, 0x74, 0x68,
+	0x2e, 0x76, 0x31, 0x61, 0x6c, 0x70, 0x68, 0x61, 0x31, 0xca, 0x02, 0x15, 0x45, 0x74, 0x68, 0x65,
+	0x72, 0x65, 0x75, 0x6d, 0x5c, 0x45, 0x74, 0x68, 0x5c, 0x76, 0x31, 0x61, 0x6c, 0x70, 0x68, 0x61,
+	0x31, 0x62, 0x06, 0x70, 0x72, 0x6f, 0x74, 0x6f, 0x33,
 }
 
 var (
@@ -290,15 +230,14 @@ func file_proto_prysm_v1alpha1_data_columns_proto_rawDescGZIP() []byte {
 	return file_proto_prysm_v1alpha1_data_columns_proto_rawDescData
 }
 
-var file_proto_prysm_v1alpha1_data_columns_proto_msgTypes = make([]protoimpl.MessageInfo, 3)
+var file_proto_prysm_v1alpha1_data_columns_proto_msgTypes = make([]protoimpl.MessageInfo, 2)
 var file_proto_prysm_v1alpha1_data_columns_proto_goTypes = []interface{}{
 	(*DataColumnSidecar)(nil),           // 0: ethereum.eth.v1alpha1.DataColumnSidecar
-	(*DataColumnIdentifier)(nil),        // 1: ethereum.eth.v1alpha1.DataColumnIdentifier
-	(*DataColumnsByRootIdentifier)(nil), // 2: ethereum.eth.v1alpha1.DataColumnsByRootIdentifier
-	(*SignedBeaconBlockHeader)(nil),     // 3: ethereum.eth.v1alpha1.SignedBeaconBlockHeader
+	(*DataColumnsByRootIdentifier)(nil), // 1: ethereum.eth.v1alpha1.DataColumnsByRootIdentifier
+	(*SignedBeaconBlockHeader)(nil),     // 2: ethereum.eth.v1alpha1.SignedBeaconBlockHeader
 }
 var file_proto_prysm_v1alpha1_data_columns_proto_depIdxs = []int32{
-	3, // 0: ethereum.eth.v1alpha1.DataColumnSidecar.signed_block_header:type_name -> ethereum.eth.v1alpha1.SignedBeaconBlockHeader
+	2, // 0: ethereum.eth.v1alpha1.DataColumnSidecar.signed_block_header:type_name -> ethereum.eth.v1alpha1.SignedBeaconBlockHeader
 	1, // [1:1] is the sub-list for method output_type
 	1, // [1:1] is the sub-list for method input_type
 	1, // [1:1] is the sub-list for extension type_name
@@ -326,18 +265,6 @@ func file_proto_prysm_v1alpha1_data_columns_proto_init() {
 			}
 		}
 		file_proto_prysm_v1alpha1_data_columns_proto_msgTypes[1].Exporter = func(v interface{}, i int) interface{} {
-			switch v := v.(*DataColumnIdentifier); i {
-			case 0:
-				return &v.state
-			case 1:
-				return &v.sizeCache
-			case 2:
-				return &v.unknownFields
-			default:
-				return nil
-			}
-		}
-		file_proto_prysm_v1alpha1_data_columns_proto_msgTypes[2].Exporter = func(v interface{}, i int) interface{} {
 			switch v := v.(*DataColumnsByRootIdentifier); i {
 			case 0:
 				return &v.state
@@ -356,7 +283,7 @@ func file_proto_prysm_v1alpha1_data_columns_proto_init() {
 			GoPackagePath: reflect.TypeOf(x{}).PkgPath(),
 			RawDescriptor: file_proto_prysm_v1alpha1_data_columns_proto_rawDesc,
 			NumEnums:      0,
-			NumMessages:   3,
+			NumMessages:   2,
 			NumExtensions: 0,
 			NumServices:   0,
 		},