zip only json

* Attest timely by default

* Fix deprecated flag naming

api/server/middleware/BUILD.bazel

@@ -8,7 +8,11 @@ go_library(
     ],
     importpath = "github.com/OffchainLabs/prysm/v6/api/server/middleware",
     visibility = ["//visibility:public"],
-    deps = ["@com_github_rs_cors//:go_default_library"],
+    deps = [
+        "//api:go_default_library",
+        "@com_github_rs_cors//:go_default_library",
+        "@com_github_sirupsen_logrus//:go_default_library",
+    ],
 )
 
 go_test(
@@ -22,5 +26,6 @@ go_test(
         "//api:go_default_library",
         "//testing/assert:go_default_library",
         "//testing/require:go_default_library",
+        "@com_github_sirupsen_logrus//:go_default_library",
     ],
 )

api/server/middleware/middleware.go

@@ -1,11 +1,14 @@
 package middleware
 
 import (
+	"compress/gzip"
 	"fmt"
 	"net/http"
 	"strings"
 
+	"github.com/OffchainLabs/prysm/v6/api"
 	"github.com/rs/cors"
+	log "github.com/sirupsen/logrus"
 )
 
 type Middleware func(http.Handler) http.Handler
@@ -112,6 +115,46 @@ func AcceptHeaderHandler(serverAcceptedTypes []string) Middleware {
 	}
 }
 
+// AcceptEncodingHeaderHandler compresses the response before sending it back to the client, if gzip is supported.
+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") {
+				next.ServeHTTP(w, r)
+				return
+			}
+
+			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")
+				}
+			}()
+
+			next.ServeHTTP(gzipRW, r)
+		})
+	}
+}
+
+type gzipResponseWriter struct {
+	gz *gzip.Writer
+	http.ResponseWriter
+	zipped bool
+}
+
+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 {
 	if len(mw) < 1 {
 		return h

api/server/middleware/middleware_test.go

@@ -1,12 +1,16 @@
 package middleware
 
 import (
+	"bytes"
+	"compress/gzip"
+	"io"
 	"net/http"
 	"net/http/httptest"
 	"testing"
 
 	"github.com/OffchainLabs/prysm/v6/api"
 	"github.com/OffchainLabs/prysm/v6/testing/require"
+	log "github.com/sirupsen/logrus"
 )
 
 func TestNormalizeQueryValuesHandler(t *testing.T) {
@@ -124,6 +128,89 @@ 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)
+	})
+
+	handler := AcceptEncodingHeaderHandler()(nextHandler)
+
+	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)
+			}
+			rr := httptest.NewRecorder()
+
+			handler.ServeHTTP(rr, req)
+
+			if tt.expectCompressed {
+				require.Equal(t, "gzip", rr.Header().Get("Content-Encoding"), "Expected Content-Encoding header to be 'gzip'")
+
+				compressedBody := rr.Body.Bytes()
+				require.NotEqual(t, dummyContent, string(compressedBody), "Response body should be compressed and differ from the original")
+
+				gzReader, err := gzip.NewReader(bytes.NewReader(compressedBody))
+				require.NoError(t, err, "Failed to create gzipReader")
+				defer func() {
+					if err := gzReader.Close(); err != nil {
+						log.WithError(err).Error("Failed to close gzip reader")
+					}
+				}()
+
+				decompressedBody, err := io.ReadAll(gzReader)
+				require.NoError(t, err, "Failed to decompress response body")
+				require.Equal(t, dummyContent, string(decompressedBody), "Decompressed content should match the original")
+			} else {
+				require.Equal(t, dummyContent, rr.Body.String(), "Response body should be uncompressed and match the original")
+			}
+		})
+	}
+}
+
 func TestAcceptHeaderHandler(t *testing.T) {
 	acceptedTypes := []string{"application/json", "application/octet-stream"}
 

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/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/endpoints.go

@@ -130,6 +130,7 @@ func (s *Service) rewardsEndpoints(blocker lookup.Blocker, stater lookup.Stater,
 			name:     namespace + ".BlockRewards",
 			middleware: []middleware.Middleware{
 				middleware.AcceptHeaderHandler([]string{api.JsonMediaType}),
+				middleware.AcceptEncodingHeaderHandler(),
 			},
 			handler: server.BlockRewards,
 			methods: []string{http.MethodGet},
@@ -140,6 +141,7 @@ func (s *Service) rewardsEndpoints(blocker lookup.Blocker, stater lookup.Stater,
 			middleware: []middleware.Middleware{
 				middleware.ContentTypeHandler([]string{api.JsonMediaType}),
 				middleware.AcceptHeaderHandler([]string{api.JsonMediaType}),
+				middleware.AcceptEncodingHeaderHandler(),
 			},
 			handler: server.AttestationRewards,
 			methods: []string{http.MethodPost},
@@ -150,6 +152,7 @@ func (s *Service) rewardsEndpoints(blocker lookup.Blocker, stater lookup.Stater,
 			middleware: []middleware.Middleware{
 				middleware.ContentTypeHandler([]string{api.JsonMediaType}),
 				middleware.AcceptHeaderHandler([]string{api.JsonMediaType}),
+				middleware.AcceptEncodingHeaderHandler(),
 			},
 			handler: server.SyncCommitteeRewards,
 			methods: []string{http.MethodPost},
@@ -172,6 +175,7 @@ func (s *Service) builderEndpoints(stater lookup.Stater) []endpoint {
 			name:     namespace + ".ExpectedWithdrawals",
 			middleware: []middleware.Middleware{
 				middleware.AcceptHeaderHandler([]string{api.JsonMediaType, api.OctetStreamMediaType}),
+				middleware.AcceptEncodingHeaderHandler(),
 			},
 			handler: server.ExpectedWithdrawals,
 			methods: []string{http.MethodGet},
@@ -194,6 +198,7 @@ func (s *Service) blobEndpoints(blocker lookup.Blocker) []endpoint {
 			name:     namespace + ".Blobs",
 			middleware: []middleware.Middleware{
 				middleware.AcceptHeaderHandler([]string{api.JsonMediaType, api.OctetStreamMediaType}),
+				middleware.AcceptEncodingHeaderHandler(),
 			},
 			handler: server.Blobs,
 			methods: []string{http.MethodGet},
@@ -237,6 +242,7 @@ func (s *Service) validatorEndpoints(
 			name:     namespace + ".GetAggregateAttestation",
 			middleware: []middleware.Middleware{
 				middleware.AcceptHeaderHandler([]string{api.JsonMediaType}),
+				middleware.AcceptEncodingHeaderHandler(),
 			},
 			handler: server.GetAggregateAttestation,
 			methods: []string{http.MethodGet},
@@ -246,6 +252,7 @@ func (s *Service) validatorEndpoints(
 			name:     namespace + ".GetAggregateAttestationV2",
 			middleware: []middleware.Middleware{
 				middleware.AcceptHeaderHandler([]string{api.JsonMediaType, api.OctetStreamMediaType}),
+				middleware.AcceptEncodingHeaderHandler(),
 			},
 			handler: server.GetAggregateAttestationV2,
 			methods: []string{http.MethodGet},
@@ -256,6 +263,7 @@ func (s *Service) validatorEndpoints(
 			middleware: []middleware.Middleware{
 				middleware.ContentTypeHandler([]string{api.JsonMediaType}),
 				middleware.AcceptHeaderHandler([]string{api.JsonMediaType}),
+				middleware.AcceptEncodingHeaderHandler(),
 			},
 			handler: server.SubmitContributionAndProofs,
 			methods: []string{http.MethodPost},
@@ -267,6 +275,7 @@ func (s *Service) validatorEndpoints(
 			middleware: []middleware.Middleware{
 				middleware.ContentTypeHandler([]string{api.JsonMediaType}),
 				middleware.AcceptHeaderHandler([]string{api.JsonMediaType}),
+				middleware.AcceptEncodingHeaderHandler(),
 			},
 			handler: server.SubmitAggregateAndProofs,
 			methods: []string{http.MethodPost},
@@ -277,6 +286,7 @@ func (s *Service) validatorEndpoints(
 			middleware: []middleware.Middleware{
 				middleware.ContentTypeHandler([]string{api.JsonMediaType}),
 				middleware.AcceptHeaderHandler([]string{api.JsonMediaType}),
+				middleware.AcceptEncodingHeaderHandler(),
 			},
 			handler: server.SubmitAggregateAndProofsV2,
 			methods: []string{http.MethodPost},
@@ -286,6 +296,7 @@ func (s *Service) validatorEndpoints(
 			name:     namespace + ".ProduceSyncCommitteeContribution",
 			middleware: []middleware.Middleware{
 				middleware.AcceptHeaderHandler([]string{api.JsonMediaType}),
+				middleware.AcceptEncodingHeaderHandler(),
 			},
 			handler: server.ProduceSyncCommitteeContribution,
 			methods: []string{http.MethodGet},
@@ -296,6 +307,7 @@ func (s *Service) validatorEndpoints(
 			middleware: []middleware.Middleware{
 				middleware.ContentTypeHandler([]string{api.JsonMediaType}),
 				middleware.AcceptHeaderHandler([]string{api.JsonMediaType}),
+				middleware.AcceptEncodingHeaderHandler(),
 			},
 			handler: server.SubmitSyncCommitteeSubscription,
 			methods: []string{http.MethodPost},
@@ -306,6 +318,7 @@ func (s *Service) validatorEndpoints(
 			middleware: []middleware.Middleware{
 				middleware.ContentTypeHandler([]string{api.JsonMediaType}),
 				middleware.AcceptHeaderHandler([]string{api.JsonMediaType}),
+				middleware.AcceptEncodingHeaderHandler(),
 			},
 			handler: server.SubmitBeaconCommitteeSubscription,
 			methods: []string{http.MethodPost},
@@ -315,6 +328,7 @@ func (s *Service) validatorEndpoints(
 			name:     namespace + ".GetAttestationData",
 			middleware: []middleware.Middleware{
 				middleware.AcceptHeaderHandler([]string{api.JsonMediaType, api.OctetStreamMediaType}),
+				middleware.AcceptEncodingHeaderHandler(),
 			},
 			handler: server.GetAttestationData,
 			methods: []string{http.MethodGet},
@@ -325,6 +339,7 @@ func (s *Service) validatorEndpoints(
 			middleware: []middleware.Middleware{
 				middleware.ContentTypeHandler([]string{api.JsonMediaType}),
 				middleware.AcceptHeaderHandler([]string{api.JsonMediaType}),
+				middleware.AcceptEncodingHeaderHandler(),
 			},
 			handler: server.RegisterValidator,
 			methods: []string{http.MethodPost},
@@ -335,6 +350,7 @@ func (s *Service) validatorEndpoints(
 			middleware: []middleware.Middleware{
 				middleware.ContentTypeHandler([]string{api.JsonMediaType}),
 				middleware.AcceptHeaderHandler([]string{api.JsonMediaType}),
+				middleware.AcceptEncodingHeaderHandler(),
 			},
 			handler: server.GetAttesterDuties,
 			methods: []string{http.MethodPost},
@@ -344,6 +360,7 @@ func (s *Service) validatorEndpoints(
 			name:     namespace + ".GetProposerDuties",
 			middleware: []middleware.Middleware{
 				middleware.AcceptHeaderHandler([]string{api.JsonMediaType}),
+				middleware.AcceptEncodingHeaderHandler(),
 			},
 			handler: server.GetProposerDuties,
 			methods: []string{http.MethodGet},
@@ -354,6 +371,7 @@ func (s *Service) validatorEndpoints(
 			middleware: []middleware.Middleware{
 				middleware.ContentTypeHandler([]string{api.JsonMediaType}),
 				middleware.AcceptHeaderHandler([]string{api.JsonMediaType}),
+				middleware.AcceptEncodingHeaderHandler(),
 			},
 			handler: server.GetSyncCommitteeDuties,
 			methods: []string{http.MethodPost},
@@ -364,6 +382,7 @@ func (s *Service) validatorEndpoints(
 			middleware: []middleware.Middleware{
 				middleware.ContentTypeHandler([]string{api.JsonMediaType}),
 				middleware.AcceptHeaderHandler([]string{api.JsonMediaType}),
+				middleware.AcceptEncodingHeaderHandler(),
 			},
 			handler: server.PrepareBeaconProposer,
 			methods: []string{http.MethodPost},
@@ -374,6 +393,7 @@ func (s *Service) validatorEndpoints(
 			middleware: []middleware.Middleware{
 				middleware.ContentTypeHandler([]string{api.JsonMediaType}),
 				middleware.AcceptHeaderHandler([]string{api.JsonMediaType}),
+				middleware.AcceptEncodingHeaderHandler(),
 			},
 			handler: server.GetLiveness,
 			methods: []string{http.MethodPost},
@@ -383,6 +403,7 @@ func (s *Service) validatorEndpoints(
 			name:     namespace + ".ProduceBlockV3",
 			middleware: []middleware.Middleware{
 				middleware.AcceptHeaderHandler([]string{api.JsonMediaType, api.OctetStreamMediaType}),
+				middleware.AcceptEncodingHeaderHandler(),
 			},
 			handler: server.ProduceBlockV3,
 			methods: []string{http.MethodGet},
@@ -429,6 +450,7 @@ func (s *Service) nodeEndpoints() []endpoint {
 			name:     namespace + ".GetSyncStatus",
 			middleware: []middleware.Middleware{
 				middleware.AcceptHeaderHandler([]string{api.JsonMediaType}),
+				middleware.AcceptEncodingHeaderHandler(),
 			},
 			handler: server.GetSyncStatus,
 			methods: []string{http.MethodGet},
@@ -438,6 +460,7 @@ func (s *Service) nodeEndpoints() []endpoint {
 			name:     namespace + ".GetIdentity",
 			middleware: []middleware.Middleware{
 				middleware.AcceptHeaderHandler([]string{api.JsonMediaType}),
+				middleware.AcceptEncodingHeaderHandler(),
 			},
 			handler: server.GetIdentity,
 			methods: []string{http.MethodGet},
@@ -447,6 +470,7 @@ func (s *Service) nodeEndpoints() []endpoint {
 			name:     namespace + ".GetPeer",
 			middleware: []middleware.Middleware{
 				middleware.AcceptHeaderHandler([]string{api.JsonMediaType}),
+				middleware.AcceptEncodingHeaderHandler(),
 			},
 			handler: server.GetPeer,
 			methods: []string{http.MethodGet},
@@ -456,6 +480,7 @@ func (s *Service) nodeEndpoints() []endpoint {
 			name:     namespace + ".GetPeers",
 			middleware: []middleware.Middleware{
 				middleware.AcceptHeaderHandler([]string{api.JsonMediaType}),
+				middleware.AcceptEncodingHeaderHandler(),
 			},
 			handler: server.GetPeers,
 			methods: []string{http.MethodGet},
@@ -465,6 +490,7 @@ func (s *Service) nodeEndpoints() []endpoint {
 			name:     namespace + ".GetPeerCount",
 			middleware: []middleware.Middleware{
 				middleware.AcceptHeaderHandler([]string{api.JsonMediaType}),
+				middleware.AcceptEncodingHeaderHandler(),
 			},
 			handler: server.GetPeerCount,
 			methods: []string{http.MethodGet},
@@ -474,6 +500,7 @@ func (s *Service) nodeEndpoints() []endpoint {
 			name:     namespace + ".GetVersion",
 			middleware: []middleware.Middleware{
 				middleware.AcceptHeaderHandler([]string{api.JsonMediaType}),
+				middleware.AcceptEncodingHeaderHandler(),
 			},
 			handler: server.GetVersion,
 			methods: []string{http.MethodGet},
@@ -483,6 +510,7 @@ func (s *Service) nodeEndpoints() []endpoint {
 			name:     namespace + ".GetHealth",
 			middleware: []middleware.Middleware{
 				middleware.AcceptHeaderHandler([]string{api.JsonMediaType}),
+				middleware.AcceptEncodingHeaderHandler(),
 			},
 			handler: server.GetHealth,
 			methods: []string{http.MethodGet},
@@ -533,6 +561,7 @@ func (s *Service) beaconEndpoints(
 			name:     namespace + ".GetCommittees",
 			middleware: []middleware.Middleware{
 				middleware.AcceptHeaderHandler([]string{api.JsonMediaType}),
+				middleware.AcceptEncodingHeaderHandler(),
 			},
 			handler: server.GetCommittees,
 			methods: []string{http.MethodGet},
@@ -542,6 +571,7 @@ func (s *Service) beaconEndpoints(
 			name:     namespace + ".GetStateFork",
 			middleware: []middleware.Middleware{
 				middleware.AcceptHeaderHandler([]string{api.JsonMediaType}),
+				middleware.AcceptEncodingHeaderHandler(),
 			},
 			handler: server.GetStateFork,
 			methods: []string{http.MethodGet},
@@ -551,6 +581,7 @@ func (s *Service) beaconEndpoints(
 			name:     namespace + ".GetStateRoot",
 			middleware: []middleware.Middleware{
 				middleware.AcceptHeaderHandler([]string{api.JsonMediaType}),
+				middleware.AcceptEncodingHeaderHandler(),
 			},
 			handler: server.GetStateRoot,
 			methods: []string{http.MethodGet},
@@ -560,6 +591,7 @@ func (s *Service) beaconEndpoints(
 			name:     namespace + ".GetSyncCommittees",
 			middleware: []middleware.Middleware{
 				middleware.AcceptHeaderHandler([]string{api.JsonMediaType}),
+				middleware.AcceptEncodingHeaderHandler(),
 			},
 			handler: server.GetSyncCommittees,
 			methods: []string{http.MethodGet},
@@ -569,6 +601,7 @@ func (s *Service) beaconEndpoints(
 			name:     namespace + ".GetRandao",
 			middleware: []middleware.Middleware{
 				middleware.AcceptHeaderHandler([]string{api.JsonMediaType}),
+				middleware.AcceptEncodingHeaderHandler(),
 			},
 			handler: server.GetRandao,
 			methods: []string{http.MethodGet},
@@ -580,6 +613,7 @@ func (s *Service) beaconEndpoints(
 			middleware: []middleware.Middleware{
 				middleware.ContentTypeHandler([]string{api.JsonMediaType, api.OctetStreamMediaType}),
 				middleware.AcceptHeaderHandler([]string{api.JsonMediaType}),
+				middleware.AcceptEncodingHeaderHandler(),
 			},
 			handler: server.PublishBlock,
 			methods: []string{http.MethodPost},
@@ -591,6 +625,7 @@ func (s *Service) beaconEndpoints(
 			middleware: []middleware.Middleware{
 				middleware.ContentTypeHandler([]string{api.JsonMediaType, api.OctetStreamMediaType}),
 				middleware.AcceptHeaderHandler([]string{api.JsonMediaType}),
+				middleware.AcceptEncodingHeaderHandler(),
 			},
 			handler: server.PublishBlindedBlock,
 			methods: []string{http.MethodPost},
@@ -601,6 +636,7 @@ func (s *Service) beaconEndpoints(
 			middleware: []middleware.Middleware{
 				middleware.ContentTypeHandler([]string{api.JsonMediaType, api.OctetStreamMediaType}),
 				middleware.AcceptHeaderHandler([]string{api.JsonMediaType}),
+				middleware.AcceptEncodingHeaderHandler(),
 			},
 			handler: server.PublishBlockV2,
 			methods: []string{http.MethodPost},
@@ -611,6 +647,7 @@ func (s *Service) beaconEndpoints(
 			middleware: []middleware.Middleware{
 				middleware.ContentTypeHandler([]string{api.JsonMediaType, api.OctetStreamMediaType}),
 				middleware.AcceptHeaderHandler([]string{api.JsonMediaType}),
+				middleware.AcceptEncodingHeaderHandler(),
 			},
 			handler: server.PublishBlindedBlockV2,
 			methods: []string{http.MethodPost},
@@ -620,6 +657,7 @@ func (s *Service) beaconEndpoints(
 			name:     namespace + ".GetBlockV2",
 			middleware: []middleware.Middleware{
 				middleware.AcceptHeaderHandler([]string{api.JsonMediaType, api.OctetStreamMediaType}),
+				middleware.AcceptEncodingHeaderHandler(),
 			},
 			handler: server.GetBlockV2,
 			methods: []string{http.MethodGet},
@@ -630,6 +668,7 @@ func (s *Service) beaconEndpoints(
 			name:     namespace + ".GetBlockAttestations",
 			middleware: []middleware.Middleware{
 				middleware.AcceptHeaderHandler([]string{api.JsonMediaType}),
+				middleware.AcceptEncodingHeaderHandler(),
 			},
 			handler: server.GetBlockAttestations,
 			methods: []string{http.MethodGet},
@@ -639,6 +678,7 @@ func (s *Service) beaconEndpoints(
 			name:     namespace + ".GetBlockAttestationsV2",
 			middleware: []middleware.Middleware{
 				middleware.AcceptHeaderHandler([]string{api.JsonMediaType}),
+				middleware.AcceptEncodingHeaderHandler(),
 			},
 			handler: server.GetBlockAttestationsV2,
 			methods: []string{http.MethodGet},
@@ -648,6 +688,7 @@ func (s *Service) beaconEndpoints(
 			name:     namespace + ".GetBlindedBlock",
 			middleware: []middleware.Middleware{
 				middleware.AcceptHeaderHandler([]string{api.JsonMediaType, api.OctetStreamMediaType}),
+				middleware.AcceptEncodingHeaderHandler(),
 			},
 			handler: server.GetBlindedBlock,
 			methods: []string{http.MethodGet},
@@ -657,6 +698,7 @@ func (s *Service) beaconEndpoints(
 			name:     namespace + ".GetBlockRoot",
 			middleware: []middleware.Middleware{
 				middleware.AcceptHeaderHandler([]string{api.JsonMediaType}),
+				middleware.AcceptEncodingHeaderHandler(),
 			},
 			handler: server.GetBlockRoot,
 			methods: []string{http.MethodGet},
@@ -667,6 +709,7 @@ func (s *Service) beaconEndpoints(
 			name:     namespace + ".ListAttestations",
 			middleware: []middleware.Middleware{
 				middleware.AcceptHeaderHandler([]string{api.JsonMediaType}),
+				middleware.AcceptEncodingHeaderHandler(),
 			},
 			handler: server.ListAttestations,
 			methods: []string{http.MethodGet},
@@ -676,6 +719,7 @@ func (s *Service) beaconEndpoints(
 			name:     namespace + ".ListAttestationsV2",
 			middleware: []middleware.Middleware{
 				middleware.AcceptHeaderHandler([]string{api.JsonMediaType}),
+				middleware.AcceptEncodingHeaderHandler(),
 			},
 			handler: server.ListAttestationsV2,
 			methods: []string{http.MethodGet},
@@ -686,6 +730,7 @@ func (s *Service) beaconEndpoints(
 			middleware: []middleware.Middleware{
 				middleware.ContentTypeHandler([]string{api.JsonMediaType}),
 				middleware.AcceptHeaderHandler([]string{api.JsonMediaType}),
+				middleware.AcceptEncodingHeaderHandler(),
 			},
 			handler: server.SubmitAttestations,
 			methods: []string{http.MethodPost},
@@ -696,6 +741,7 @@ func (s *Service) beaconEndpoints(
 			middleware: []middleware.Middleware{
 				middleware.ContentTypeHandler([]string{api.JsonMediaType}),
 				middleware.AcceptHeaderHandler([]string{api.JsonMediaType}),
+				middleware.AcceptEncodingHeaderHandler(),
 			},
 			handler: server.SubmitAttestationsV2,
 			methods: []string{http.MethodPost},
@@ -705,6 +751,7 @@ func (s *Service) beaconEndpoints(
 			name:     namespace + ".ListVoluntaryExits",
 			middleware: []middleware.Middleware{
 				middleware.AcceptHeaderHandler([]string{api.JsonMediaType}),
+				middleware.AcceptEncodingHeaderHandler(),
 			},
 			handler: server.ListVoluntaryExits,
 			methods: []string{http.MethodGet},
@@ -715,6 +762,7 @@ func (s *Service) beaconEndpoints(
 			middleware: []middleware.Middleware{
 				middleware.ContentTypeHandler([]string{api.JsonMediaType}),
 				middleware.AcceptHeaderHandler([]string{api.JsonMediaType}),
+				middleware.AcceptEncodingHeaderHandler(),
 			},
 			handler: server.SubmitVoluntaryExit,
 			methods: []string{http.MethodPost},
@@ -725,6 +773,7 @@ func (s *Service) beaconEndpoints(
 			middleware: []middleware.Middleware{
 				middleware.ContentTypeHandler([]string{api.JsonMediaType}),
 				middleware.AcceptHeaderHandler([]string{api.JsonMediaType}),
+				middleware.AcceptEncodingHeaderHandler(),
 			},
 			handler: server.SubmitSyncCommitteeSignatures,
 			methods: []string{http.MethodPost},
@@ -734,6 +783,7 @@ func (s *Service) beaconEndpoints(
 			name:     namespace + ".ListBLSToExecutionChanges",
 			middleware: []middleware.Middleware{
 				middleware.AcceptHeaderHandler([]string{api.JsonMediaType}),
+				middleware.AcceptEncodingHeaderHandler(),
 			},
 			handler: server.ListBLSToExecutionChanges,
 			methods: []string{http.MethodGet},
@@ -744,6 +794,7 @@ func (s *Service) beaconEndpoints(
 			middleware: []middleware.Middleware{
 				middleware.ContentTypeHandler([]string{api.JsonMediaType}),
 				middleware.AcceptHeaderHandler([]string{api.JsonMediaType}),
+				middleware.AcceptEncodingHeaderHandler(),
 			},
 			handler: server.SubmitBLSToExecutionChanges,
 			methods: []string{http.MethodPost},
@@ -754,6 +805,7 @@ func (s *Service) beaconEndpoints(
 			name:     namespace + ".GetAttesterSlashings",
 			middleware: []middleware.Middleware{
 				middleware.AcceptHeaderHandler([]string{api.JsonMediaType}),
+				middleware.AcceptEncodingHeaderHandler(),
 			},
 			handler: server.GetAttesterSlashings,
 			methods: []string{http.MethodGet},
@@ -763,6 +815,7 @@ func (s *Service) beaconEndpoints(
 			name:     namespace + ".GetAttesterSlashingsV2",
 			middleware: []middleware.Middleware{
 				middleware.AcceptHeaderHandler([]string{api.JsonMediaType}),
+				middleware.AcceptEncodingHeaderHandler(),
 			},
 			handler: server.GetAttesterSlashingsV2,
 			methods: []string{http.MethodGet},
@@ -773,6 +826,7 @@ func (s *Service) beaconEndpoints(
 			middleware: []middleware.Middleware{
 				middleware.ContentTypeHandler([]string{api.JsonMediaType}),
 				middleware.AcceptHeaderHandler([]string{api.JsonMediaType}),
+				middleware.AcceptEncodingHeaderHandler(),
 			},
 			handler: server.SubmitAttesterSlashings,
 			methods: []string{http.MethodPost},
@@ -783,6 +837,7 @@ func (s *Service) beaconEndpoints(
 			middleware: []middleware.Middleware{
 				middleware.ContentTypeHandler([]string{api.JsonMediaType}),
 				middleware.AcceptHeaderHandler([]string{api.JsonMediaType}),
+				middleware.AcceptEncodingHeaderHandler(),
 			},
 			handler: server.SubmitAttesterSlashingsV2,
 			methods: []string{http.MethodPost},
@@ -792,6 +847,7 @@ func (s *Service) beaconEndpoints(
 			name:     namespace + ".GetProposerSlashings",
 			middleware: []middleware.Middleware{
 				middleware.AcceptHeaderHandler([]string{api.JsonMediaType}),
+				middleware.AcceptEncodingHeaderHandler(),
 			},
 			handler: server.GetProposerSlashings,
 			methods: []string{http.MethodGet},
@@ -802,6 +858,7 @@ func (s *Service) beaconEndpoints(
 			middleware: []middleware.Middleware{
 				middleware.ContentTypeHandler([]string{api.JsonMediaType}),
 				middleware.AcceptHeaderHandler([]string{api.JsonMediaType}),
+				middleware.AcceptEncodingHeaderHandler(),
 			},
 			handler: server.SubmitProposerSlashing,
 			methods: []string{http.MethodPost},
@@ -811,6 +868,7 @@ func (s *Service) beaconEndpoints(
 			name:     namespace + ".GetBlockHeaders",
 			middleware: []middleware.Middleware{
 				middleware.AcceptHeaderHandler([]string{api.JsonMediaType}),
+				middleware.AcceptEncodingHeaderHandler(),
 			},
 			handler: server.GetBlockHeaders,
 			methods: []string{http.MethodGet},
@@ -820,6 +878,7 @@ func (s *Service) beaconEndpoints(
 			name:     namespace + ".GetBlockHeader",
 			middleware: []middleware.Middleware{
 				middleware.AcceptHeaderHandler([]string{api.JsonMediaType}),
+				middleware.AcceptEncodingHeaderHandler(),
 			},
 			handler: server.GetBlockHeader,
 			methods: []string{http.MethodGet},
@@ -829,6 +888,7 @@ func (s *Service) beaconEndpoints(
 			name:     namespace + ".GetGenesis",
 			middleware: []middleware.Middleware{
 				middleware.AcceptHeaderHandler([]string{api.JsonMediaType}),
+				middleware.AcceptEncodingHeaderHandler(),
 			},
 			handler: server.GetGenesis,
 			methods: []string{http.MethodGet},
@@ -838,6 +898,7 @@ func (s *Service) beaconEndpoints(
 			name:     namespace + ".GetFinalityCheckpoints",
 			middleware: []middleware.Middleware{
 				middleware.AcceptHeaderHandler([]string{api.JsonMediaType}),
+				middleware.AcceptEncodingHeaderHandler(),
 			},
 			handler: server.GetFinalityCheckpoints,
 			methods: []string{http.MethodGet},
@@ -848,6 +909,7 @@ func (s *Service) beaconEndpoints(
 			middleware: []middleware.Middleware{
 				middleware.ContentTypeHandler([]string{api.JsonMediaType}),
 				middleware.AcceptHeaderHandler([]string{api.JsonMediaType}),
+				middleware.AcceptEncodingHeaderHandler(),
 			},
 			handler: server.GetValidators,
 			methods: []string{http.MethodGet, http.MethodPost},
@@ -857,6 +919,7 @@ func (s *Service) beaconEndpoints(
 			name:     namespace + ".GetValidator",
 			middleware: []middleware.Middleware{
 				middleware.AcceptHeaderHandler([]string{api.JsonMediaType}),
+				middleware.AcceptEncodingHeaderHandler(),
 			},
 			handler: server.GetValidator,
 			methods: []string{http.MethodGet},
@@ -867,6 +930,7 @@ func (s *Service) beaconEndpoints(
 			middleware: []middleware.Middleware{
 				middleware.ContentTypeHandler([]string{api.JsonMediaType}),
 				middleware.AcceptHeaderHandler([]string{api.JsonMediaType}),
+				middleware.AcceptEncodingHeaderHandler(),
 			},
 			handler: server.GetValidatorBalances,
 			methods: []string{http.MethodGet, http.MethodPost},
@@ -887,6 +951,7 @@ func (s *Service) beaconEndpoints(
 			name:     namespace + ".GetDepositSnapshot",
 			middleware: []middleware.Middleware{
 				middleware.AcceptHeaderHandler([]string{api.JsonMediaType}),
+				middleware.AcceptEncodingHeaderHandler(),
 			},
 			handler: server.GetDepositSnapshot,
 			methods: []string{http.MethodGet},
@@ -896,6 +961,7 @@ func (s *Service) beaconEndpoints(
 			name:     namespace + ".GetPendingDeposits",
 			middleware: []middleware.Middleware{
 				middleware.AcceptHeaderHandler([]string{api.JsonMediaType}),
+				middleware.AcceptEncodingHeaderHandler(),
 			},
 			handler: server.GetPendingDeposits,
 			methods: []string{http.MethodGet},
@@ -914,6 +980,7 @@ func (s *Service) beaconEndpoints(
 			name:     namespace + ".GetPendingPartialWithdrawals",
 			middleware: []middleware.Middleware{
 				middleware.AcceptHeaderHandler([]string{api.JsonMediaType}),
+				middleware.AcceptEncodingHeaderHandler(),
 			},
 			handler: server.GetPendingPartialWithdrawals,
 			methods: []string{http.MethodGet},
@@ -929,6 +996,7 @@ func (*Service) configEndpoints() []endpoint {
 			name:     namespace + ".GetDepositContract",
 			middleware: []middleware.Middleware{
 				middleware.AcceptHeaderHandler([]string{api.JsonMediaType}),
+				middleware.AcceptEncodingHeaderHandler(),
 			},
 			handler: config.GetDepositContract,
 			methods: []string{http.MethodGet},
@@ -938,6 +1006,7 @@ func (*Service) configEndpoints() []endpoint {
 			name:     namespace + ".GetForkSchedule",
 			middleware: []middleware.Middleware{
 				middleware.AcceptHeaderHandler([]string{api.JsonMediaType}),
+				middleware.AcceptEncodingHeaderHandler(),
 			},
 			handler: config.GetForkSchedule,
 			methods: []string{http.MethodGet},
@@ -947,6 +1016,7 @@ func (*Service) configEndpoints() []endpoint {
 			name:     namespace + ".GetSpec",
 			middleware: []middleware.Middleware{
 				middleware.AcceptHeaderHandler([]string{api.JsonMediaType}),
+				middleware.AcceptEncodingHeaderHandler(),
 			},
 			handler: config.GetSpec,
 			methods: []string{http.MethodGet},
@@ -971,6 +1041,7 @@ func (s *Service) lightClientEndpoints(blocker lookup.Blocker, stater lookup.Sta
 			name:     namespace + ".GetLightClientBootstrap",
 			middleware: []middleware.Middleware{
 				middleware.AcceptHeaderHandler([]string{api.JsonMediaType, api.OctetStreamMediaType}),
+				middleware.AcceptEncodingHeaderHandler(),
 			},
 			handler: server.GetLightClientBootstrap,
 			methods: []string{http.MethodGet},
@@ -980,6 +1051,7 @@ func (s *Service) lightClientEndpoints(blocker lookup.Blocker, stater lookup.Sta
 			name:     namespace + ".GetLightClientUpdatesByRange",
 			middleware: []middleware.Middleware{
 				middleware.AcceptHeaderHandler([]string{api.JsonMediaType, api.OctetStreamMediaType}),
+				middleware.AcceptEncodingHeaderHandler(),
 			},
 			handler: server.GetLightClientUpdatesByRange,
 			methods: []string{http.MethodGet},
@@ -989,6 +1061,7 @@ func (s *Service) lightClientEndpoints(blocker lookup.Blocker, stater lookup.Sta
 			name:     namespace + ".GetLightClientFinalityUpdate",
 			middleware: []middleware.Middleware{
 				middleware.AcceptHeaderHandler([]string{api.JsonMediaType, api.OctetStreamMediaType}),
+				middleware.AcceptEncodingHeaderHandler(),
 			},
 			handler: server.GetLightClientFinalityUpdate,
 			methods: []string{http.MethodGet},
@@ -998,6 +1071,7 @@ func (s *Service) lightClientEndpoints(blocker lookup.Blocker, stater lookup.Sta
 			name:     namespace + ".GetLightClientOptimisticUpdate",
 			middleware: []middleware.Middleware{
 				middleware.AcceptHeaderHandler([]string{api.JsonMediaType, api.OctetStreamMediaType}),
+				middleware.AcceptEncodingHeaderHandler(),
 			},
 			handler: server.GetLightClientOptimisticUpdate,
 			methods: []string{http.MethodGet},
@@ -1024,6 +1098,7 @@ func (s *Service) debugEndpoints(stater lookup.Stater) []endpoint {
 			name:     namespace + ".GetBeaconStateV2",
 			middleware: []middleware.Middleware{
 				middleware.AcceptHeaderHandler([]string{api.JsonMediaType, api.OctetStreamMediaType}),
+				middleware.AcceptEncodingHeaderHandler(),
 			},
 			handler: server.GetBeaconStateV2,
 			methods: []string{http.MethodGet},
@@ -1033,6 +1108,7 @@ func (s *Service) debugEndpoints(stater lookup.Stater) []endpoint {
 			name:     namespace + ".GetForkChoiceHeadsV2",
 			middleware: []middleware.Middleware{
 				middleware.AcceptHeaderHandler([]string{api.JsonMediaType}),
+				middleware.AcceptEncodingHeaderHandler(),
 			},
 			handler: server.GetForkChoiceHeadsV2,
 			methods: []string{http.MethodGet},
@@ -1042,6 +1118,7 @@ func (s *Service) debugEndpoints(stater lookup.Stater) []endpoint {
 			name:     namespace + ".GetForkChoice",
 			middleware: []middleware.Middleware{
 				middleware.AcceptHeaderHandler([]string{api.JsonMediaType}),
+				middleware.AcceptEncodingHeaderHandler(),
 			},
 			handler: server.GetForkChoice,
 			methods: []string{http.MethodGet},
@@ -1066,6 +1143,7 @@ func (s *Service) eventsEndpoints() []endpoint {
 			name:     namespace + ".StreamEvents",
 			middleware: []middleware.Middleware{
 				middleware.AcceptHeaderHandler([]string{api.EventStreamMediaType}),
+				middleware.AcceptEncodingHeaderHandler(),
 			},
 			handler: server.StreamEvents,
 			methods: []string{http.MethodGet},
@@ -1101,6 +1179,7 @@ func (s *Service) prysmBeaconEndpoints(
 			name:     namespace + ".GetWeakSubjectivity",
 			middleware: []middleware.Middleware{
 				middleware.AcceptHeaderHandler([]string{api.JsonMediaType}),
+				middleware.AcceptEncodingHeaderHandler(),
 			},
 			handler: server.GetWeakSubjectivity,
 			methods: []string{http.MethodGet},
@@ -1110,6 +1189,7 @@ func (s *Service) prysmBeaconEndpoints(
 			name:     namespace + ".GetValidatorCount",
 			middleware: []middleware.Middleware{
 				middleware.AcceptHeaderHandler([]string{api.JsonMediaType}),
+				middleware.AcceptEncodingHeaderHandler(),
 			},
 			handler: server.GetValidatorCount,
 			methods: []string{http.MethodGet},
@@ -1119,6 +1199,7 @@ func (s *Service) prysmBeaconEndpoints(
 			name:     namespace + ".GetValidatorCount",
 			middleware: []middleware.Middleware{
 				middleware.AcceptHeaderHandler([]string{api.JsonMediaType}),
+				middleware.AcceptEncodingHeaderHandler(),
 			},
 			handler: server.GetValidatorCount,
 			methods: []string{http.MethodGet},
@@ -1129,6 +1210,7 @@ func (s *Service) prysmBeaconEndpoints(
 			middleware: []middleware.Middleware{
 				middleware.ContentTypeHandler([]string{api.JsonMediaType}),
 				middleware.AcceptHeaderHandler([]string{api.JsonMediaType}),
+				middleware.AcceptEncodingHeaderHandler(),
 			},
 			handler: server.GetIndividualVotes,
 			methods: []string{http.MethodPost},
@@ -1138,6 +1220,7 @@ func (s *Service) prysmBeaconEndpoints(
 			name:     namespace + ".GetChainHead",
 			middleware: []middleware.Middleware{
 				middleware.AcceptHeaderHandler([]string{api.JsonMediaType}),
+				middleware.AcceptEncodingHeaderHandler(),
 			},
 			handler: server.GetChainHead,
 			methods: []string{http.MethodGet},
@@ -1148,6 +1231,7 @@ func (s *Service) prysmBeaconEndpoints(
 			middleware: []middleware.Middleware{
 				middleware.ContentTypeHandler([]string{api.JsonMediaType}),
 				middleware.AcceptHeaderHandler([]string{api.JsonMediaType}),
+				middleware.AcceptEncodingHeaderHandler(),
 			},
 			handler: server.PublishBlobs,
 			methods: []string{http.MethodPost},
@@ -1175,6 +1259,7 @@ func (s *Service) prysmNodeEndpoints() []endpoint {
 			name:     namespace + ".ListTrustedPeer",
 			middleware: []middleware.Middleware{
 				middleware.AcceptHeaderHandler([]string{api.JsonMediaType}),
+				middleware.AcceptEncodingHeaderHandler(),
 			},
 			handler: server.ListTrustedPeer,
 			methods: []string{http.MethodGet},
@@ -1184,6 +1269,7 @@ func (s *Service) prysmNodeEndpoints() []endpoint {
 			name:     namespace + ".ListTrustedPeer",
 			middleware: []middleware.Middleware{
 				middleware.AcceptHeaderHandler([]string{api.JsonMediaType}),
+				middleware.AcceptEncodingHeaderHandler(),
 			},
 			handler: server.ListTrustedPeer,
 			methods: []string{http.MethodGet},
@@ -1194,6 +1280,7 @@ func (s *Service) prysmNodeEndpoints() []endpoint {
 			middleware: []middleware.Middleware{
 				middleware.ContentTypeHandler([]string{api.JsonMediaType}),
 				middleware.AcceptHeaderHandler([]string{api.JsonMediaType}),
+				middleware.AcceptEncodingHeaderHandler(),
 			},
 			handler: server.AddTrustedPeer,
 			methods: []string{http.MethodPost},
@@ -1204,6 +1291,7 @@ func (s *Service) prysmNodeEndpoints() []endpoint {
 			middleware: []middleware.Middleware{
 				middleware.ContentTypeHandler([]string{api.JsonMediaType}),
 				middleware.AcceptHeaderHandler([]string{api.JsonMediaType}),
+				middleware.AcceptEncodingHeaderHandler(),
 			},
 			handler: server.AddTrustedPeer,
 			methods: []string{http.MethodPost},
@@ -1213,6 +1301,7 @@ func (s *Service) prysmNodeEndpoints() []endpoint {
 			name:     namespace + ".RemoveTrustedPeer",
 			middleware: []middleware.Middleware{
 				middleware.AcceptHeaderHandler([]string{api.JsonMediaType}),
+				middleware.AcceptEncodingHeaderHandler(),
 			},
 			handler: server.RemoveTrustedPeer,
 			methods: []string{http.MethodDelete},
@@ -1222,6 +1311,7 @@ func (s *Service) prysmNodeEndpoints() []endpoint {
 			name:     namespace + ".RemoveTrustedPeer",
 			middleware: []middleware.Middleware{
 				middleware.AcceptHeaderHandler([]string{api.JsonMediaType}),
+				middleware.AcceptEncodingHeaderHandler(),
 			},
 			handler: server.RemoveTrustedPeer,
 			methods: []string{http.MethodDelete},
@@ -1244,6 +1334,7 @@ func (s *Service) prysmValidatorEndpoints(stater lookup.Stater, coreService *cor
 			middleware: []middleware.Middleware{
 				middleware.ContentTypeHandler([]string{api.JsonMediaType}),
 				middleware.AcceptHeaderHandler([]string{api.JsonMediaType}),
+				middleware.AcceptEncodingHeaderHandler(),
 			},
 			handler: server.GetPerformance,
 			methods: []string{http.MethodPost},
@@ -1254,6 +1345,7 @@ func (s *Service) prysmValidatorEndpoints(stater lookup.Stater, coreService *cor
 			middleware: []middleware.Middleware{
 				middleware.ContentTypeHandler([]string{api.JsonMediaType}),
 				middleware.AcceptHeaderHandler([]string{api.JsonMediaType}),
+				middleware.AcceptEncodingHeaderHandler(),
 			},
 			handler: server.GetPerformance,
 			methods: []string{http.MethodPost},
@@ -1263,6 +1355,7 @@ func (s *Service) prysmValidatorEndpoints(stater lookup.Stater, coreService *cor
 			name:     namespace + ".GetParticipation",
 			middleware: []middleware.Middleware{
 				middleware.AcceptHeaderHandler([]string{api.JsonMediaType}),
+				middleware.AcceptEncodingHeaderHandler(),
 			},
 			handler: server.GetParticipation,
 			methods: []string{http.MethodGet},
@@ -1272,6 +1365,7 @@ func (s *Service) prysmValidatorEndpoints(stater lookup.Stater, coreService *cor
 			name:     namespace + ".GetActiveSetChanges",
 			middleware: []middleware.Middleware{
 				middleware.AcceptHeaderHandler([]string{api.JsonMediaType}),
+				middleware.AcceptEncodingHeaderHandler(),
 			},
 			handler: server.GetActiveSetChanges,
 			methods: []string{http.MethodGet},

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",
@@ -40,6 +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",
@@ -78,6 +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",
@@ -162,6 +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",
@@ -207,6 +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",
@@ -214,6 +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",

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

@@ -210,6 +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

@@ -55,9 +55,10 @@ func newRateLimiter(p2pProvider p2p.P2P) *limiter {
 	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

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), 18, "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_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 {

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"
@@ -30,16 +32,18 @@ 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")
 )
 
 // ------
@@ -397,6 +401,245 @@ func readChunkedBlobSidecar(stream network.Stream, encoding encoder.NetworkEncod
 // 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

beacon-chain/sync/rpc_send_request_test.go

@@ -11,7 +11,9 @@ import (
 
 	"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"
@@ -885,6 +887,544 @@ 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"

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
+}

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/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-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/rose2221-develop.md

@@ -0,0 +1,5 @@
+### Added
+
+- **Gzip Compression for Beacon API:**  
+  Fixed an issue where the beacon chain server ignored the `Accept-Encoding: gzip` header and returned uncompressed JSON responses. With this change, endpoints that use the `AcceptHeaderHandler` now also compress responses when a client requests gzip encoding. 
+  Fixes [#14593](https://github.com/prysmaticlabs/prysm/issues/14593).

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

cmd/beacon-chain/flags/base.go

@@ -338,4 +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/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

@@ -156,7 +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")
 		}
@@ -168,11 +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
@@ -317,9 +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)

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",
@@ -222,7 +222,7 @@ var ValidatorFlags = append(deprecatedFlags, []cli.Flag{
 	HoodiTestnet,
 	Mainnet,
 	dynamicKeyReloadDebounceInterval,
-	attestTimely,
+	disableAttestTimely,
 	enableSlashingProtectionPruning,
 	EnableMinimalSlashingProtection,
 	enableDoppelGangerProtection,

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 {

testing/spectest/minimal/electra__light_client__single_merkle_proof_test.go

@@ -7,6 +7,6 @@ import (
 	"github.com/OffchainLabs/prysm/v6/testing/spectest/shared/common/light_client"
 )
 
-func TestMainnet_Electra_LightClient_SingleMerkleProof(t *testing.T) {
+func TestMinimal_Electra_LightClient_SingleMerkleProof(t *testing.T) {
 	light_client.RunLightClientSingleMerkleProofTests(t, "minimal", version.Electra)
 }

testing/spectest/minimal/electra__light_client__update_ranking_test.go

@@ -7,6 +7,6 @@ import (
 	"github.com/OffchainLabs/prysm/v6/testing/spectest/shared/common/light_client"
 )
 
-func TestMainnet_Electra_LightClient_UpdateRanking(t *testing.T) {
+func TestMinimal_Electra_LightClient_UpdateRanking(t *testing.T) {
 	light_client.RunLightClientUpdateRankingTests(t, "minimal", version.Electra)
 }

testing/spectest/shared/common/light_client/BUILD.bazel

@@ -14,6 +14,7 @@ go_library(
         "//beacon-chain/core/light-client:go_default_library",
         "//beacon-chain/state:go_default_library",
         "//beacon-chain/state/state-native:go_default_library",
+        "//config/params:go_default_library",
         "//consensus-types/interfaces:go_default_library",
         "//consensus-types/light-client:go_default_library",
         "//container/trie:go_default_library",

testing/spectest/shared/common/light_client/update_ranking.go

@@ -7,6 +7,7 @@ import (
 
 	"github.com/OffchainLabs/prysm/v6/beacon-chain/core/helpers"
 	lightclient "github.com/OffchainLabs/prysm/v6/beacon-chain/core/light-client"
+	"github.com/OffchainLabs/prysm/v6/config/params"
 	"github.com/OffchainLabs/prysm/v6/consensus-types/interfaces"
 	lightclienttypes "github.com/OffchainLabs/prysm/v6/consensus-types/light-client"
 	ethpb "github.com/OffchainLabs/prysm/v6/proto/prysm/v1alpha1"
@@ -20,6 +21,24 @@ import (
 // RunLightClientUpdateRankingTests executes "light_client/update_ranking/pyspec_tests/update_ranking" tests.
 func RunLightClientUpdateRankingTests(t *testing.T, config string, v int) {
 	require.NoError(t, utils.SetConfig(t, config))
+	if v >= version.Altair {
+		params.BeaconConfig().AltairForkEpoch = 0
+	}
+	if v >= version.Bellatrix {
+		params.BeaconConfig().BellatrixForkEpoch = 0
+	}
+	if v >= version.Capella {
+		params.BeaconConfig().CapellaForkEpoch = 0
+	}
+	if v >= version.Deneb {
+		params.BeaconConfig().DenebForkEpoch = 0
+	}
+	if v >= version.Electra {
+		params.BeaconConfig().ElectraForkEpoch = 0
+	}
+	if v >= version.Fulu {
+		params.BeaconConfig().FuluForkEpoch = 0
+	}
 
 	_, testsFolderPath := utils.TestFolders(t, config, version.String(v), "light_client/update_ranking/pyspec_tests/")
 	testTypes, err := util.BazelListDirectories(testsFolderPath)

testing/util/fulu.go

@@ -1,7 +1,6 @@
 package util
 
 import (
-	"encoding/binary"
 	"math/big"
 	"testing"
 
@@ -110,14 +109,21 @@ func GenerateTestFuluBlockWithSidecars(t *testing.T, blobCount int, options ...F
 	block.Block.ParentRoot = generator.parent[:]
 	block.Block.ProposerIndex = generator.proposer
 
-	block.Block.Body.BlobKzgCommitments = make([][]byte, blobCount)
-	for i := range blobCount {
-		var commitment [fieldparams.KzgCommitmentSize]byte
-		binary.LittleEndian.PutUint16(commitment[:16], uint16(i))
-		binary.LittleEndian.PutUint16(commitment[16:32], uint16(generator.slot))
-		block.Block.Body.BlobKzgCommitments[i] = commitment[:]
+	blobs := make([]kzg.Blob, 0, generator.blobCount)
+	commitments := make([][]byte, 0, generator.blobCount)
+
+	for i := range generator.blobCount {
+		blob := kzg.Blob{uint8(i)}
+
+		commitment, err := kzg.BlobToKZGCommitment(&blob)
+		require.NoError(t, err)
+
+		blobs = append(blobs, blob)
+		commitments = append(commitments, commitment[:])
 	}
 
+	block.Block.Body.BlobKzgCommitments = commitments
+
 	body, err := blocks.NewBeaconBlockBody(block.Block.Body)
 	require.NoError(t, err)
 
@@ -149,39 +155,30 @@ func GenerateTestFuluBlockWithSidecars(t *testing.T, blobCount int, options ...F
 	root, err := block.Block.HashTreeRoot()
 	require.NoError(t, err)
 
-	sbb, err := blocks.NewSignedBeaconBlock(block)
+	signedBeaconBlock, err := blocks.NewSignedBeaconBlock(block)
 	require.NoError(t, err)
 
-	sh, err := sbb.Header()
-	require.NoError(t, err)
-
-	blobs := make([]kzg.Blob, blobCount)
-	for i, commitment := range block.Block.Body.BlobKzgCommitments {
-		roSidecars := GenerateTestDenebBlobSidecar(t, root, sh, i, commitment, inclusion[i])
-		blobs[i] = kzg.Blob(roSidecars.Blob)
-	}
-
 	cellsAndProofs := GenerateCellsAndProofs(t, blobs)
 
-	dataColumns, err := peerdas.DataColumnSidecars(sbb, cellsAndProofs)
+	sidecars, err := peerdas.DataColumnSidecars(signedBeaconBlock, cellsAndProofs)
 	require.NoError(t, err)
 
-	roSidecars := make([]blocks.RODataColumn, 0, len(dataColumns))
-	roVerifiedSidecars := make([]blocks.VerifiedRODataColumn, 0, len(dataColumns))
-	for _, dataColumn := range dataColumns {
-		roSidecar, err := blocks.NewRODataColumnWithRoot(dataColumn, root)
+	roSidecars := make([]blocks.RODataColumn, 0, len(sidecars))
+	verifiedRoSidecars := make([]blocks.VerifiedRODataColumn, 0, len(sidecars))
+	for _, sidecar := range sidecars {
+		roSidecar, err := blocks.NewRODataColumnWithRoot(sidecar, root)
 		require.NoError(t, err)
 
 		roVerifiedSidecar := blocks.NewVerifiedRODataColumn(roSidecar)
 
 		roSidecars = append(roSidecars, roSidecar)
-		roVerifiedSidecars = append(roVerifiedSidecars, roVerifiedSidecar)
+		verifiedRoSidecars = append(verifiedRoSidecars, roVerifiedSidecar)
 	}
 
-	rob, err := blocks.NewROBlockWithRoot(sbb, root)
+	roBlock, err := blocks.NewROBlockWithRoot(signedBeaconBlock, root)
 	require.NoError(t, err)
 
-	return rob, roSidecars, roVerifiedSidecars
+	return roBlock, roSidecars, verifiedRoSidecars
 }
 
 func GenerateCellsAndProofs(t testing.TB, blobs []kzg.Blob) []kzg.CellsAndProofs {