Merge branch 'eip_7917' into fusaka-devnet-1

* `ExchangeCapabilities`: Transform `O(n**2)` into `O(2n)` and fix logging.

* Find peers with subnets and logs: Refactor

* Validator custody: Do not wait being subscribed to advertise correct `cgc`. (temp hack)

CHANGELOG.md

@@ -4,6 +4,49 @@ All notable changes to this project will be documented in this file.
 
 The format is based on Keep a Changelog, and this project adheres to Semantic Versioning.
 
+## [v6.0.4](https://github.com/prysmaticlabs/prysm/compare/v6.0.3...v6.0.4) - 2025-06-05
+
+This release has more work on PeerDAS, and light client support. Additionally, we have a few bug fixes:
+- Blob cache size now correctly set at startup.
+- A fix for slashing protection history exports where the validator database was in a nested folder.
+- Corrected behavior of the API call for state committees with an invalid request.
+- `/bin/sh` is now symlinked to `/bin/bash` for Prysm docker images.
+
+In the [Hoodi](https://github.com/eth-clients/hoodi) testnet, the default gas limit is raised to 60M gas. 
+
+### Added
+
+- Add light client mainnet spec test. [[PR]](https://github.com/prysmaticlabs/prysm/pull/15295)
+- Add support for light client req/resp domain. [[PR]](https://github.com/prysmaticlabs/prysm/pull/15281)
+- Added /bin/sh simlink to docker images. [[PR]](https://github.com/prysmaticlabs/prysm/pull/15294)
+- Added Prysm build data to otel tracing spans. [[PR]](https://github.com/prysmaticlabs/prysm/pull/15302)
+- Add light client minimal spec test support for `update_ranking` tests. [[PR]](https://github.com/prysmaticlabs/prysm/pull/15297)
+- Add fulu operation and epoch processing spec tests. [[PR]](https://github.com/prysmaticlabs/prysm/pull/15284)
+- Updated e2e Beacon API evaluator to support more endpoints, including the ones introduced in Electra. [[PR]](https://github.com/prysmaticlabs/prysm/pull/15304)
+- Data column sidecars verification methods. [[PR]](https://github.com/prysmaticlabs/prysm/pull/15232)
+- Implement data column sidecars filesystem. [[PR]](https://github.com/prysmaticlabs/prysm/pull/15257)
+- Add blob schedule support from https://github.com/ethereum/consensus-specs/pull/4277. [[PR]](https://github.com/prysmaticlabs/prysm/pull/15272)
+-  random forkchoice spec tests for fulu. [[PR]](https://github.com/prysmaticlabs/prysm/pull/15287)
+- Add ability to download nightly test vectors. [[PR]](https://github.com/prysmaticlabs/prysm/pull/15312)
+- PeerDAS: Validation pipeline for data column sidecars received via gossip. [[PR]](https://github.com/prysmaticlabs/prysm/pull/15310)
+- PeerDAS: Implement P2P. [[PR]](https://github.com/prysmaticlabs/prysm/pull/15347)
+- PeerDAS: Implement the blockchain package. [[PR]](https://github.com/prysmaticlabs/prysm/pull/15350)
+
+### Changed
+
+- Update spec tests to v1.6.0-alpha.0. [[PR]](https://github.com/prysmaticlabs/prysm/pull/15306)
+- PeerDAS: Refactor the reconstruction pipeline. [[PR]](https://github.com/prysmaticlabs/prysm/pull/15309)
+- PeerDAS: `DataColumnStorage.Get` - Exit early no columns are available. [[PR]](https://github.com/prysmaticlabs/prysm/pull/15309)
+- Default hoodi testnet builder gas limit to 60M. [[PR]](https://github.com/prysmaticlabs/prysm/pull/15361)
+
+### Fixed
+
+- Fix cyclical dependencies issue when using testing/util package. [[PR]](https://github.com/prysmaticlabs/prysm/pull/15248)
+- Set seen blob cache size correctly based on current slot time at start up. [[PR]](https://github.com/prysmaticlabs/prysm/pull/15348)
+- Fix `slashing-protection-history export` failing when `validator.db` is in a nested folder like `data/direct/`. (#14954). [[PR]](https://github.com/prysmaticlabs/prysm/pull/15351)
+- Made `/eth/v1/beacon/states/{state_id}/committees` endpoint return `400` when slot does not belong to the specified epoch, aligning with the Beacon API spec (#15355). [[PR]](https://github.com/prysmaticlabs/prysm/pull/15356)
+- Removed eager validator context cancellation that was causing validator builder registrations to fail occasionally. [[PR]](https://github.com/prysmaticlabs/prysm/pull/15369)
+
 ## [v6.0.3](https://github.com/prysmaticlabs/prysm/compare/v6.0.2...v6.0.3) - 2025-05-21
 
 This release has important bugfixes for users of the [Beacon API](https://ethereum.github.io/beacon-APIs/). These fixes include:

WORKSPACE

@@ -1,7 +1,7 @@
 workspace(name = "prysm")
 
-load("@bazel_tools//tools/build_defs/repo:http.bzl", "http_archive")
 load("@bazel_tools//tools/build_defs/repo:git.bzl", "git_repository")
+load("@bazel_tools//tools/build_defs/repo:http.bzl", "http_archive")
 
 http_archive(
     name = "rules_pkg",
@@ -16,8 +16,6 @@ load("@rules_pkg//:deps.bzl", "rules_pkg_dependencies")
 
 rules_pkg_dependencies()
 
-load("@bazel_tools//tools/build_defs/repo:http.bzl", "http_archive")
-
 http_archive(
     name = "toolchains_protoc",
     sha256 = "abb1540f8a9e045422730670ebb2f25b41fa56ca5a7cf795175a110a0a68f4ad",
@@ -255,16 +253,16 @@ filegroup(
     url = "https://github.com/ethereum/EIPs/archive/5480440fe51742ed23342b68cf106cefd427e39d.tar.gz",
 )
 
-consensus_spec_version = "v1.6.0-alpha.0"
+consensus_spec_version = "v1.6.0-alpha.1"
 
 load("@prysm//tools:download_spectests.bzl", "consensus_spec_tests")
 
 consensus_spec_tests(
     name = "consensus_spec_tests",
     flavors = {
-        "general": "sha256-W7oKvoM0nAkyitykRxAw6kmCvjYC01IqiNJy0AmCnMM=",
-        "minimal": "sha256-ig7/zxomjv6buBWMom4IxAJh3lFJ9+JnY44E7c8ZNP8=",
-        "mainnet": "sha256-mjx+MkXtPhCNv4c4knLYLIkvIdpF7WTjx/ElvGPQzSo=",
+        "general": "sha256-o4t9p3R+fQHF4KOykGmwlG3zDw5wUdVWprkzId8aIsk=",
+        "minimal": "sha256-sU7ToI8t3MR8x0vVjC8ERmAHZDWpEmnAC9FWIpHi5x4=",
+        "mainnet": "sha256-YKS4wngg0LgI9Upp4MYJ77aG+8+e/G4YeqEIlp06LZw=",
     },
     version = consensus_spec_version,
 )
@@ -280,7 +278,7 @@ filegroup(
     visibility = ["//visibility:public"],
 )
     """,
-    integrity = "sha256-u0RkIZIeGttb3sInR31mO64aBSwxALqO5SYIPlqEvPo=",
+    integrity = "sha256-Nv4TEuEJPQIM4E6T9J0FOITsmappmXZjGtlhe1HEXnU=",
     strip_prefix = "consensus-specs-" + consensus_spec_version[1:],
     url = "https://github.com/ethereum/consensus-specs/archive/refs/tags/%s.tar.gz" % consensus_spec_version,
 )

api/server/structs/conversions_state.go

@@ -923,7 +923,14 @@ func BeaconStateFuluFromConsensus(st beaconState.BeaconState) (*BeaconStateFulu,
 	if err != nil {
 		return nil, err
 	}
-
+	srcLookahead, err := st.ProposerLookahead()
+	if err != nil {
+		return nil, err
+	}
+	lookahead := make([]string, len(srcLookahead))
+	for i, v := range srcLookahead {
+		lookahead[i] = fmt.Sprintf("%d", uint64(v))
+	}
 	return &BeaconStateFulu{
 		GenesisTime:                   fmt.Sprintf("%d", st.GenesisTime()),
 		GenesisValidatorsRoot:         hexutil.Encode(st.GenesisValidatorsRoot()),
@@ -962,5 +969,6 @@ func BeaconStateFuluFromConsensus(st beaconState.BeaconState) (*BeaconStateFulu,
 		PendingDeposits:               PendingDepositsFromConsensus(pbd),
 		PendingPartialWithdrawals:     PendingPartialWithdrawalsFromConsensus(ppw),
 		PendingConsolidations:         PendingConsolidationsFromConsensus(pc),
+		ProposerLookahead:             lookahead,
 	}, nil
 }

api/server/structs/endpoints_node.go

@@ -33,8 +33,14 @@ type GetPeerResponse struct {
 	Data *Peer `json:"data"`
 }
 
+// Added Meta to align with beacon-api: https://ethereum.github.io/beacon-APIs/#/Node/getPeers
+type Meta struct {
+	Count int `json:"count"`
+}
+
 type GetPeersResponse struct {
 	Data []*Peer `json:"data"`
+	Meta Meta    `json:"meta"`
 }
 
 type Peer struct {

api/server/structs/state.go

@@ -219,4 +219,5 @@ type BeaconStateFulu struct {
 	PendingDeposits               []*PendingDeposit            `json:"pending_deposits"`
 	PendingPartialWithdrawals     []*PendingPartialWithdrawal  `json:"pending_partial_withdrawals"`
 	PendingConsolidations         []*PendingConsolidation      `json:"pending_consolidations"`
+	ProposerLookahead             []string                     `json:"proposer_lookahead"`
 }

beacon-chain/blockchain/service.go

@@ -31,6 +31,7 @@ import (
 	"github.com/OffchainLabs/prysm/v6/beacon-chain/startup"
 	"github.com/OffchainLabs/prysm/v6/beacon-chain/state"
 	"github.com/OffchainLabs/prysm/v6/beacon-chain/state/stategen"
+	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"
@@ -109,22 +110,26 @@ var ErrMissingClockSetter = errors.New("blockchain Service initialized without a
 type blobNotifierMap struct {
 	sync.RWMutex
 	notifiers map[[32]byte]chan uint64
-	seenIndex map[[32]byte][]bool
+	// TODO: Separate blobs from data columns
+	// seenIndex map[[32]byte][]bool
+	seenIndex map[[32]byte][fieldparams.NumberOfColumns]bool
 }
 
 // notifyIndex notifies a blob by its index for a given root.
 // It uses internal maps to keep track of seen indices and notifier channels.
 func (bn *blobNotifierMap) notifyIndex(root [32]byte, idx uint64, slot primitives.Slot) {
-	maxBlobsPerBlock := params.BeaconConfig().MaxBlobsPerBlock(slot)
-	if idx >= uint64(maxBlobsPerBlock) {
-		return
-	}
+	// TODO: Separate blobs from data columns
+	// maxBlobsPerBlock := params.BeaconConfig().MaxBlobsPerBlock(slot)
+	// if idx >= uint64(maxBlobsPerBlock) {
+	// 	return
+	// }
 
 	bn.Lock()
 	seen := bn.seenIndex[root]
-	if seen == nil {
-		seen = make([]bool, maxBlobsPerBlock)
-	}
+	// TODO: Separate blobs from data columns
+	// if seen == nil {
+	// seen = make([]bool, maxBlobsPerBlock)
+	// }
 	if seen[idx] {
 		bn.Unlock()
 		return
@@ -135,7 +140,9 @@ func (bn *blobNotifierMap) notifyIndex(root [32]byte, idx uint64, slot primitive
 	// Retrieve or create the notifier channel for the given root.
 	c, ok := bn.notifiers[root]
 	if !ok {
-		c = make(chan uint64, maxBlobsPerBlock)
+		// TODO: Separate blobs from data columns
+		// c = make(chan uint64, maxBlobsPerBlock)
+		c = make(chan uint64, fieldparams.NumberOfColumns)
 		bn.notifiers[root] = c
 	}
 
@@ -145,12 +152,15 @@ func (bn *blobNotifierMap) notifyIndex(root [32]byte, idx uint64, slot primitive
 }
 
 func (bn *blobNotifierMap) forRoot(root [32]byte, slot primitives.Slot) chan uint64 {
-	maxBlobsPerBlock := params.BeaconConfig().MaxBlobsPerBlock(slot)
+	// TODO: Separate blobs from data columns
+	// maxBlobsPerBlock := params.BeaconConfig().MaxBlobsPerBlock(slot)
 	bn.Lock()
 	defer bn.Unlock()
 	c, ok := bn.notifiers[root]
 	if !ok {
-		c = make(chan uint64, maxBlobsPerBlock)
+		// TODO: Separate blobs from data columns
+		// c = make(chan uint64, maxBlobsPerBlock)
+		c = make(chan uint64, fieldparams.NumberOfColumns)
 		bn.notifiers[root] = c
 	}
 	return c
@@ -176,7 +186,9 @@ func NewService(ctx context.Context, opts ...Option) (*Service, error) {
 	ctx, cancel := context.WithCancel(ctx)
 	bn := &blobNotifierMap{
 		notifiers: make(map[[32]byte]chan uint64),
-		seenIndex: make(map[[32]byte][]bool),
+		// TODO: Separate blobs from data columns
+		// seenIndex: make(map[[32]byte][]bool),
+		seenIndex: make(map[[32]byte][fieldparams.NumberOfColumns]bool),
 	}
 	srv := &Service{
 		ctx:                  ctx,

beacon-chain/blockchain/service_test.go

@@ -587,7 +587,9 @@ func (s *MockClockSetter) SetClock(g *startup.Clock) error {
 func TestNotifyIndex(t *testing.T) {
 	// Initialize a blobNotifierMap
 	bn := &blobNotifierMap{
-		seenIndex: make(map[[32]byte][]bool),
+		// TODO: Separate blobs from data columns
+		// seenIndex: make(map[[32]byte][]bool),
+		seenIndex: make(map[[32]byte][fieldparams.NumberOfColumns]bool),
 		notifiers: make(map[[32]byte]chan uint64),
 	}
 

beacon-chain/core/blocks/payload.go

@@ -229,13 +229,16 @@ func verifyBlobCommitmentCount(slot primitives.Slot, body interfaces.ReadOnlyBea
 	if body.Version() < version.Deneb {
 		return nil
 	}
+
 	kzgs, err := body.BlobKzgCommitments()
 	if err != nil {
 		return err
 	}
-	maxBlobsPerBlock := params.BeaconConfig().MaxBlobsPerBlock(slot)
-	if len(kzgs) > maxBlobsPerBlock {
-		return fmt.Errorf("too many kzg commitments in block: %d", len(kzgs))
+
+	commitmentCount, maxBlobsPerBlock := len(kzgs), params.BeaconConfig().MaxBlobsPerBlock(slot)
+	if commitmentCount > maxBlobsPerBlock {
+		return fmt.Errorf("too many kzg commitments in block: actual count %d - max allowed %d", commitmentCount, maxBlobsPerBlock)
 	}
+
 	return nil
 }

beacon-chain/core/blocks/payload_test.go

@@ -926,8 +926,10 @@ func TestVerifyBlobCommitmentCount(t *testing.T) {
 	require.NoError(t, err)
 	require.NoError(t, blocks.VerifyBlobCommitmentCount(rb.Slot(), rb.Body()))
 
-	b = &ethpb.BeaconBlockDeneb{Body: &ethpb.BeaconBlockBodyDeneb{BlobKzgCommitments: make([][]byte, params.BeaconConfig().MaxBlobsPerBlock(rb.Slot())+1)}}
+	maxCommitmentsPerBlock := params.BeaconConfig().MaxBlobsPerBlock(rb.Slot())
+
+	b = &ethpb.BeaconBlockDeneb{Body: &ethpb.BeaconBlockBodyDeneb{BlobKzgCommitments: make([][]byte, maxCommitmentsPerBlock+1)}}
 	rb, err = consensusblocks.NewBeaconBlock(b)
 	require.NoError(t, err)
-	require.ErrorContains(t, fmt.Sprintf("too many kzg commitments in block: %d", params.BeaconConfig().MaxBlobsPerBlock(rb.Slot())+1), blocks.VerifyBlobCommitmentCount(rb.Slot(), rb.Body()))
+	require.ErrorContains(t, fmt.Sprintf("too many kzg commitments in block: actual count %d - max allowed %d", maxCommitmentsPerBlock+1, maxCommitmentsPerBlock), blocks.VerifyBlobCommitmentCount(rb.Slot(), rb.Body()))
 }

beacon-chain/core/blocks/signature.go

@@ -96,6 +96,24 @@ func VerifyBlockHeaderSignature(beaconState state.BeaconState, header *ethpb.Sig
 	return signing.VerifyBlockHeaderSigningRoot(header.Header, proposerPubKey, header.Signature, domain)
 }
 
+func VerifyBlockHeaderSignatureUsingCurrentFork(beaconState state.BeaconState, header *ethpb.SignedBeaconBlockHeader) error {
+	currentEpoch := slots.ToEpoch(header.Header.Slot)
+	fork, err := forks.Fork(currentEpoch)
+	if err != nil {
+		return err
+	}
+	domain, err := signing.Domain(fork, currentEpoch, params.BeaconConfig().DomainBeaconProposer, beaconState.GenesisValidatorsRoot())
+	if err != nil {
+		return err
+	}
+	proposer, err := beaconState.ValidatorAtIndex(header.Header.ProposerIndex)
+	if err != nil {
+		return err
+	}
+	proposerPubKey := proposer.PublicKey
+	return signing.VerifyBlockHeaderSigningRoot(header.Header, proposerPubKey, header.Signature, domain)
+}
+
 // VerifyBlockSignatureUsingCurrentFork verifies the proposer signature of a beacon block. This differs
 // from the above method by not using fork data from the state and instead retrieving it
 // via the respective epoch.

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

@@ -37,8 +37,11 @@ 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
 )
 
 // UnAggregatedAttReceivedData is the data sent with UnaggregatedAttReceived events.
@@ -90,6 +93,11 @@ 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/fulu/BUILD.bazel

@@ -2,23 +2,33 @@ load("@prysm//tools/go:def.bzl", "go_library", "go_test")
 
 go_library(
     name = "go_default_library",
-    srcs = ["upgrade.go"],
+    srcs = [
+        "transition.go",
+        "upgrade.go",
+    ],
     importpath = "github.com/OffchainLabs/prysm/v6/beacon-chain/core/fulu",
     visibility = ["//visibility:public"],
     deps = [
+        "//beacon-chain/core/electra:go_default_library",
+        "//beacon-chain/core/helpers:go_default_library",
         "//beacon-chain/core/time:go_default_library",
         "//beacon-chain/state:go_default_library",
         "//beacon-chain/state/state-native:go_default_library",
         "//config/params:go_default_library",
+        "//monitoring/tracing/trace:go_default_library",
         "//proto/engine/v1:go_default_library",
         "//proto/prysm/v1alpha1:go_default_library",
+        "//time/slots:go_default_library",
         "@com_github_pkg_errors//:go_default_library",
     ],
 )
 
 go_test(
     name = "go_default_test",
-    srcs = ["upgrade_test.go"],
+    srcs = [
+        "transition_test.go",
+        "upgrade_test.go",
+    ],
     deps = [
         ":go_default_library",
         "//beacon-chain/core/time:go_default_library",

beacon-chain/core/fulu/transition.go

@@ -0,0 +1,47 @@
+package fulu
+
+import (
+	"context"
+
+	"github.com/OffchainLabs/prysm/v6/beacon-chain/core/electra"
+	"github.com/OffchainLabs/prysm/v6/beacon-chain/core/helpers"
+	"github.com/OffchainLabs/prysm/v6/beacon-chain/state"
+	"github.com/OffchainLabs/prysm/v6/config/params"
+	"github.com/OffchainLabs/prysm/v6/monitoring/tracing/trace"
+	"github.com/OffchainLabs/prysm/v6/time/slots"
+	"github.com/pkg/errors"
+)
+
+func ProcessEpoch(ctx context.Context, state state.BeaconState) error {
+	if err := electra.ProcessEpoch(ctx, state); err != nil {
+		return errors.Wrap(err, "could not process epoch in fulu transition")
+	}
+	return processProposerLookahead(ctx, state)
+}
+
+func processProposerLookahead(ctx context.Context, state state.BeaconState) error {
+	_, span := trace.StartSpan(ctx, "fulu.processProposerLookahead")
+	defer span.End()
+
+	if state == nil || state.IsNil() {
+		return errors.New("nil state")
+	}
+
+	lookAhead, err := state.ProposerLookahead()
+	if err != nil {
+		return errors.Wrap(err, "could not get proposer lookahead")
+	}
+	lastEpochStart := len(lookAhead) - int(params.BeaconConfig().SlotsPerEpoch)
+	copy(lookAhead[:lastEpochStart], lookAhead[params.BeaconConfig().SlotsPerEpoch:])
+	lastEpoch := slots.ToEpoch(state.Slot()) + params.BeaconConfig().MinSeedLookahead + 1
+	indices, err := helpers.ActiveValidatorIndices(ctx, state, lastEpoch)
+	if err != nil {
+		return err
+	}
+	lastEpochProposers, err := helpers.PrecomputeProposerIndices(state, indices, lastEpoch)
+	if err != nil {
+		return errors.Wrap(err, "could not precompute proposer indices")
+	}
+	copy(lookAhead[lastEpochStart:], lastEpochProposers)
+	return state.SetProposerLookahead(lookAhead)
+}

beacon-chain/core/fulu/transition_test.go

@@ -0,0 +1,28 @@
+package fulu_test
+
+import (
+	"context"
+	"testing"
+
+	"github.com/OffchainLabs/prysm/v6/beacon-chain/core/fulu"
+	"github.com/OffchainLabs/prysm/v6/config/params"
+	"github.com/OffchainLabs/prysm/v6/testing/require"
+	"github.com/OffchainLabs/prysm/v6/testing/util"
+)
+
+func TestProcessEpoch_CanProcessFulu(t *testing.T) {
+	st, _ := util.DeterministicGenesisStateElectra(t, params.BeaconConfig().MaxValidatorsPerCommittee)
+	require.NoError(t, st.SetSlot(10*params.BeaconConfig().SlotsPerEpoch))
+	st, err := fulu.UpgradeToFulu(context.Background(), st)
+	require.NoError(t, err)
+	preLookahead, err := st.ProposerLookahead()
+	require.NoError(t, err)
+	err = fulu.ProcessEpoch(context.Background(), st)
+	require.NoError(t, err)
+	postLookahead, err := st.ProposerLookahead()
+	require.NoError(t, err)
+	require.NotEqual(t, preLookahead[0], postLookahead[0])
+	for i, v := range preLookahead[params.BeaconConfig().SlotsPerEpoch:] {
+		require.Equal(t, v, postLookahead[i])
+	}
+}

beacon-chain/core/fulu/upgrade.go

@@ -1,18 +1,22 @@
 package fulu
 
 import (
+	"context"
+
+	"github.com/OffchainLabs/prysm/v6/beacon-chain/core/helpers"
 	"github.com/OffchainLabs/prysm/v6/beacon-chain/core/time"
 	"github.com/OffchainLabs/prysm/v6/beacon-chain/state"
 	state_native "github.com/OffchainLabs/prysm/v6/beacon-chain/state/state-native"
 	"github.com/OffchainLabs/prysm/v6/config/params"
 	enginev1 "github.com/OffchainLabs/prysm/v6/proto/engine/v1"
 	ethpb "github.com/OffchainLabs/prysm/v6/proto/prysm/v1alpha1"
+	"github.com/OffchainLabs/prysm/v6/time/slots"
 	"github.com/pkg/errors"
 )
 
 // UpgradeToFulu updates inputs a generic state to return the version Fulu state.
 // https://github.com/ethereum/consensus-specs/blob/v1.5.0-beta.5/specs/fulu/fork.md#upgrading-the-state
-func UpgradeToFulu(beaconState state.BeaconState) (state.BeaconState, error) {
+func UpgradeToFulu(ctx context.Context, beaconState state.BeaconState) (state.BeaconState, error) {
 	currentSyncCommittee, err := beaconState.CurrentSyncCommittee()
 	if err != nil {
 		return nil, err
@@ -101,8 +105,12 @@ func UpgradeToFulu(beaconState state.BeaconState) (state.BeaconState, error) {
 	if err != nil {
 		return nil, err
 	}
+	proposerLookahead, err := helpers.InitializeProposerLookahead(ctx, beaconState, slots.ToEpoch(beaconState.Slot()))
+	if err != nil {
+		return nil, err
+	}
 
-	s := &ethpb.BeaconStateElectra{
+	s := &ethpb.BeaconStateFulu{
 		GenesisTime:           beaconState.GenesisTime(),
 		GenesisValidatorsRoot: beaconState.GenesisValidatorsRoot(),
 		Slot:                  beaconState.Slot(),
@@ -163,6 +171,7 @@ func UpgradeToFulu(beaconState state.BeaconState) (state.BeaconState, error) {
 		PendingDeposits:               pendingDeposits,
 		PendingPartialWithdrawals:     pendingPartialWithdrawals,
 		PendingConsolidations:         pendingConsolidations,
+		ProposerLookahead:             proposerLookahead,
 	}
 
 	// Need to cast the beaconState to use in helper functions

beacon-chain/core/fulu/upgrade_test.go

@@ -1,6 +1,7 @@
 package fulu_test
 
 import (
+	"context"
 	"testing"
 
 	"github.com/OffchainLabs/prysm/v6/beacon-chain/core/fulu"
@@ -25,7 +26,7 @@ func TestUpgradeToFulu(t *testing.T) {
 	require.NoError(t, st.SetBalances(bals))
 
 	preForkState := st.Copy()
-	mSt, err := fulu.UpgradeToFulu(st)
+	mSt, err := fulu.UpgradeToFulu(context.Background(), st)
 	require.NoError(t, err)
 
 	require.Equal(t, preForkState.GenesisTime(), mSt.GenesisTime())

beacon-chain/core/helpers/beacon_committee.go

@@ -277,10 +277,10 @@ type CommitteeAssignment struct {
 	CommitteeIndex primitives.CommitteeIndex
 }
 
-// verifyAssignmentEpoch verifies if the given epoch is valid for assignment based on the provided state.
+// VerifyAssignmentEpoch verifies if the given epoch is valid for assignment based on the provided state.
 // It checks if the epoch is not greater than the next epoch, and if the start slot of the epoch is greater
 // than or equal to the minimum valid start slot calculated based on the state's current slot and historical roots.
-func verifyAssignmentEpoch(epoch primitives.Epoch, state state.BeaconState) error {
+func VerifyAssignmentEpoch(epoch primitives.Epoch, state state.BeaconState) error {
 	nextEpoch := time.NextEpoch(state)
 	if epoch > nextEpoch {
 		return fmt.Errorf("epoch %d can't be greater than next epoch %d", epoch, nextEpoch)
@@ -308,7 +308,7 @@ func ProposerAssignments(ctx context.Context, state state.BeaconState, epoch pri
 	defer span.End()
 
 	// Verify if the epoch is valid for assignment based on the provided state.
-	if err := verifyAssignmentEpoch(epoch, state); err != nil {
+	if err := VerifyAssignmentEpoch(epoch, state); err != nil {
 		return nil, err
 	}
 	startSlot, err := slots.EpochStart(epoch)
@@ -351,6 +351,61 @@ func ProposerAssignments(ctx context.Context, state state.BeaconState, epoch pri
 	return proposerAssignments, nil
 }
 
+// LiteAssignment is a lite version of CommitteeAssignment, and has committee length
+// and validator committee index instead of the full committee list
+type LiteAssignment struct {
+	AttesterSlot            primitives.Slot           // slot in which to attest
+	CommitteeIndex          primitives.CommitteeIndex // position of the committee in the slot
+	CommitteeLength         uint64                    // number of members in the committee
+	ValidatorCommitteeIndex uint64                    // validator’s offset inside the committee
+}
+
+// PrecomputeCommittees returns an array indexed by (slot-startSlot)
+// whose elements are the beacon committees of that slot.
+func PrecomputeCommittees(
+	ctx context.Context,
+	st state.BeaconState,
+	startSlot primitives.Slot,
+) ([][][]primitives.ValidatorIndex, error) {
+	cfg := params.BeaconConfig()
+	out := make([][][]primitives.ValidatorIndex, cfg.SlotsPerEpoch)
+
+	for relativeSlot := primitives.Slot(0); relativeSlot < cfg.SlotsPerEpoch; relativeSlot++ {
+		slot := startSlot + relativeSlot
+
+		comms, err := BeaconCommittees(ctx, st, slot)
+		if err != nil {
+			return nil, errors.Wrapf(err, "BeaconCommittees failed at slot %d", slot)
+		}
+		out[relativeSlot] = comms
+	}
+	return out, nil
+}
+
+// AssignmentForValidator scans the cached committees once
+// and returns the duty for a single validator.
+func AssignmentForValidator(
+	bySlot [][][]primitives.ValidatorIndex,
+	startSlot primitives.Slot,
+	vIdx primitives.ValidatorIndex,
+) *LiteAssignment {
+	for relativeSlot, committees := range bySlot {
+		for cIdx, committee := range committees {
+			for pos, member := range committee {
+				if member == vIdx {
+					return &LiteAssignment{
+						AttesterSlot:            startSlot + primitives.Slot(relativeSlot),
+						CommitteeIndex:          primitives.CommitteeIndex(cIdx),
+						CommitteeLength:         uint64(len(committee)),
+						ValidatorCommitteeIndex: uint64(pos),
+					}
+				}
+			}
+		}
+	}
+	return nil // validator is not scheduled this epoch
+}
+
 // CommitteeAssignments calculates committee assignments for each validator during the specified epoch.
 // It retrieves active validator indices, determines the number of committees per slot, and computes
 // assignments for each validator based on their presence in the provided validators slice.
@@ -359,7 +414,7 @@ func CommitteeAssignments(ctx context.Context, state state.BeaconState, epoch pr
 	defer span.End()
 
 	// Verify if the epoch is valid for assignment based on the provided state.
-	if err := verifyAssignmentEpoch(epoch, state); err != nil {
+	if err := VerifyAssignmentEpoch(epoch, state); err != nil {
 		return nil, err
 	}
 	startSlot, err := slots.EpochStart(epoch)
@@ -500,21 +555,31 @@ func UpdateProposerIndicesInCache(ctx context.Context, state state.ReadOnlyBeaco
 	if err != nil {
 		return err
 	}
-	// Skip cache update if the key already exists
-	_, ok := proposerIndicesCache.ProposerIndices(epoch, [32]byte(root))
-	if ok {
-		return nil
-	}
-	indices, err := ActiveValidatorIndices(ctx, state, epoch)
-	if err != nil {
-		return err
-	}
-	proposerIndices, err := PrecomputeProposerIndices(state, indices, epoch)
-	if err != nil {
-		return err
-	}
-	if len(proposerIndices) != int(params.BeaconConfig().SlotsPerEpoch) {
-		return errors.New("invalid proposer length returned from state")
+	var proposerIndices []primitives.ValidatorIndex
+	// use the state if post fulu (EIP-7917)
+	if state.Version() >= version.Fulu {
+		lookAhead, err := state.ProposerLookahead()
+		if err != nil {
+			return errors.Wrap(err, "could not get proposer lookahead")
+		}
+		proposerIndices = lookAhead[:params.BeaconConfig().SlotsPerEpoch]
+	} else {
+		// Skip cache update if the key already exists
+		_, ok := proposerIndicesCache.ProposerIndices(epoch, [32]byte(root))
+		if ok {
+			return nil
+		}
+		indices, err := ActiveValidatorIndices(ctx, state, epoch)
+		if err != nil {
+			return err
+		}
+		proposerIndices, err = PrecomputeProposerIndices(state, indices, epoch)
+		if err != nil {
+			return err
+		}
+		if len(proposerIndices) != int(params.BeaconConfig().SlotsPerEpoch) {
+			return errors.New("invalid proposer length returned from state")
+		}
 	}
 	// This is here to deal with tests only
 	var indicesArray [fieldparams.SlotsPerEpoch]primitives.ValidatorIndex
@@ -601,6 +666,25 @@ func ComputeCommittee(
 	return shuffledList[start:end], nil
 }
 
+// InitializeProposerLookahead computes the list of the proposer indices for the next couple of epochs.
+func InitializeProposerLookahead(ctx context.Context, state state.ReadOnlyBeaconState, epoch primitives.Epoch) ([]uint64, error) {
+	lookAhead := make([]uint64, 0, uint64(params.BeaconConfig().MinSeedLookahead+1)*uint64(params.BeaconConfig().SlotsPerEpoch))
+	indices, err := ActiveValidatorIndices(ctx, state, epoch)
+	if err != nil {
+		return nil, errors.Wrap(err, "could not get active indices")
+	}
+	for i := uint64(0); i < uint64(params.BeaconConfig().MinSeedLookahead+1); i++ {
+		proposerIndices, err := PrecomputeProposerIndices(state, indices, epoch+primitives.Epoch(i))
+		if err != nil {
+			return nil, errors.Wrap(err, "could not compute proposer indices")
+		}
+		for _, proposerIndex := range proposerIndices {
+			lookAhead = append(lookAhead, uint64(proposerIndex))
+		}
+	}
+	return lookAhead, nil
+}
+
 // PrecomputeProposerIndices computes proposer indices of the current epoch and returns a list of proposer indices,
 // the index of the list represents the slot number.
 func PrecomputeProposerIndices(state state.ReadOnlyBeaconState, activeIndices []primitives.ValidatorIndex, e primitives.Epoch) ([]primitives.ValidatorIndex, error) {

beacon-chain/core/helpers/beacon_committee_test.go

@@ -871,3 +871,48 @@ func TestBeaconCommitteesFromCache(t *testing.T) {
 		assert.DeepEqual(t, committees[idx], committee)
 	}
 }
+
+func TestPrecomputeCommittees_HappyPath(t *testing.T) {
+	cfg := params.BeaconConfig()
+	start := primitives.Slot(100)
+	ctx := context.Background()
+	st, _ := util.DeterministicGenesisState(t, 256)
+
+	got, err := helpers.PrecomputeCommittees(ctx, st, start)
+
+	require.NoError(t, err)
+	require.Equal(t, len(got), int(cfg.SlotsPerEpoch), "outer slice length mismatch")
+
+	for i := range got {
+		expSlot := start + primitives.Slot(i)
+		comms, err := helpers.BeaconCommittees(ctx, st, expSlot)
+		require.NoError(t, err)
+		require.DeepEqual(t, comms, got[i])
+	}
+}
+
+func TestAssignmentForValidator(t *testing.T) {
+	start := primitives.Slot(200)
+	bySlot := [][][]primitives.ValidatorIndex{
+		{{1, 2, 3}},
+		{{7, 8, 9}},
+	}
+	vIdx := primitives.ValidatorIndex(8)
+
+	got := helpers.AssignmentForValidator(bySlot, start, vIdx)
+
+	require.NotNil(t, got)
+	require.Equal(t, start+1, got.AttesterSlot)
+	require.Equal(t, primitives.CommitteeIndex(0), got.CommitteeIndex)
+	require.Equal(t, uint64(3), got.CommitteeLength)
+	require.Equal(t, uint64(1), got.ValidatorCommitteeIndex)
+
+	t.Run("Not Found", func(t *testing.T) {
+		start = primitives.Slot(300)
+		bySlot = [][][]primitives.ValidatorIndex{
+			{{4, 5, 6}},
+		}
+		got = helpers.AssignmentForValidator(bySlot, start, primitives.ValidatorIndex(99))
+		require.IsNil(t, got)
+	})
+}

beacon-chain/core/helpers/sync_committee_test.go

@@ -78,6 +78,7 @@ func TestIsCurrentEpochSyncCommittee_UsingCommittee(t *testing.T) {
 
 func TestIsCurrentEpochSyncCommittee_DoesNotExist(t *testing.T) {
 	helpers.ClearCache()
+	params.SetupTestConfigCleanup(t)
 
 	validators := make([]*ethpb.Validator, params.BeaconConfig().SyncCommitteeSize)
 	syncCommittee := &ethpb.SyncCommittee{
@@ -264,6 +265,7 @@ func TestCurrentEpochSyncSubcommitteeIndices_UsingCommittee(t *testing.T) {
 }
 
 func TestCurrentEpochSyncSubcommitteeIndices_DoesNotExist(t *testing.T) {
+	params.SetupTestConfigCleanup(t)
 	helpers.ClearCache()
 
 	validators := make([]*ethpb.Validator, params.BeaconConfig().SyncCommitteeSize)

beacon-chain/core/helpers/validators.go

@@ -299,9 +299,29 @@ func ProposerIndexAtSlotFromCheckpoint(c *forkchoicetypes.Checkpoint, slot primi
 	return proposerIndices[slot%params.BeaconConfig().SlotsPerEpoch], nil
 }
 
+func beaconProposerIndexAtSlotFulu(state state.ReadOnlyBeaconState, slot primitives.Slot) (primitives.ValidatorIndex, error) {
+	e := slots.ToEpoch(slot)
+	stateEpoch := slots.ToEpoch(state.Slot())
+	if e < stateEpoch || e > stateEpoch+1 {
+		return 0, errors.Errorf("slot %d is not in the current epoch %d or the next epoch", slot, stateEpoch)
+	}
+	lookAhead, err := state.ProposerLookahead()
+	if err != nil {
+		return 0, errors.Wrap(err, "could not get proposer lookahead")
+	}
+	if e == stateEpoch {
+		return lookAhead[slot%params.BeaconConfig().SlotsPerEpoch], nil
+	}
+	// The caller is requesting the proposer for the next epoch
+	return lookAhead[slot%params.BeaconConfig().SlotsPerEpoch+params.BeaconConfig().SlotsPerEpoch], nil
+}
+
 // BeaconProposerIndexAtSlot returns proposer index at the given slot from the
 // point of view of the given state as head state
 func BeaconProposerIndexAtSlot(ctx context.Context, state state.ReadOnlyBeaconState, slot primitives.Slot) (primitives.ValidatorIndex, error) {
+	if state.Version() >= version.Fulu {
+		return beaconProposerIndexAtSlotFulu(state, slot)
+	}
 	e := slots.ToEpoch(slot)
 	// The cache uses the state root of the previous epoch - minimum_seed_lookahead last slot as key. (e.g. Starting epoch 1, slot 32, the key would be block root at slot 31)
 	// For simplicity, the node will skip caching of genesis epoch.

beacon-chain/core/peerdas/BUILD.bazel

@@ -7,6 +7,7 @@ go_library(
         "info.go",
         "metrics.go",
         "p2p_interface.go",
+        "peer_sampling.go",
         "reconstruction.go",
         "validator.go",
         "verification.go",
@@ -44,6 +45,7 @@ go_test(
         "das_core_test.go",
         "info_test.go",
         "p2p_interface_test.go",
+        "peer_sampling_test.go",
         "reconstruction_test.go",
         "utils_test.go",
         "validator_test.go",

beacon-chain/core/peerdas/peer_sampling.go

@@ -0,0 +1,56 @@
+package peerdas
+
+import (
+	"math/big"
+
+	"github.com/OffchainLabs/prysm/v6/config/params"
+)
+
+// ExtendedSampleCount computes, for a given number of samples per slot and allowed failures the
+// number of samples we should actually query from peers.
+// https://github.com/ethereum/consensus-specs/blob/v1.5.0-beta.5/specs/fulu/peer-sampling.md#get_extended_sample_count
+func ExtendedSampleCount(samplesPerSlot, allowedFailures uint64) uint64 {
+	// Retrieve the columns count
+	columnsCount := params.BeaconConfig().NumberOfColumns
+
+	// If half of the columns are missing, we are able to reconstruct the data.
+	// If half of the columns + 1 are missing, we are not able to reconstruct the data.
+	// This is the smallest worst case.
+	worstCaseMissing := columnsCount/2 + 1
+
+	// Compute the false positive threshold.
+	falsePositiveThreshold := HypergeomCDF(0, columnsCount, worstCaseMissing, samplesPerSlot)
+
+	var sampleCount uint64
+
+	// Finally, compute the extended sample count.
+	for sampleCount = samplesPerSlot; sampleCount < columnsCount+1; sampleCount++ {
+		if HypergeomCDF(allowedFailures, columnsCount, worstCaseMissing, sampleCount) <= falsePositiveThreshold {
+			break
+		}
+	}
+
+	return sampleCount
+}
+
+// HypergeomCDF computes the hypergeometric cumulative distribution function.
+// https://en.wikipedia.org/wiki/Hypergeometric_distribution
+func HypergeomCDF(k, M, n, N uint64) float64 {
+	denominatorInt := new(big.Int).Binomial(int64(M), int64(N)) // lint:ignore uintcast
+	denominator := new(big.Float).SetInt(denominatorInt)
+
+	rBig := big.NewFloat(0)
+
+	for i := uint64(0); i < k+1; i++ {
+		a := new(big.Int).Binomial(int64(n), int64(i)) // lint:ignore uintcast
+		b := new(big.Int).Binomial(int64(M-n), int64(N-i))
+		numeratorInt := new(big.Int).Mul(a, b)
+		numerator := new(big.Float).SetInt(numeratorInt)
+		item := new(big.Float).Quo(numerator, denominator)
+		rBig.Add(rBig, item)
+	}
+
+	r, _ := rBig.Float64()
+
+	return r
+}

beacon-chain/core/peerdas/peer_sampling_test.go

@@ -0,0 +1,60 @@
+package peerdas_test
+
+import (
+	"testing"
+
+	"github.com/OffchainLabs/prysm/v6/beacon-chain/core/peerdas"
+	"github.com/OffchainLabs/prysm/v6/testing/require"
+)
+
+func TestExtendedSampleCount(t *testing.T) {
+	const samplesPerSlot = 16
+
+	testCases := []struct {
+		name                string
+		allowedMissings     uint64
+		extendedSampleCount uint64
+	}{
+		{name: "allowedMissings=0", allowedMissings: 0, extendedSampleCount: 16},
+		{name: "allowedMissings=1", allowedMissings: 1, extendedSampleCount: 20},
+		{name: "allowedMissings=2", allowedMissings: 2, extendedSampleCount: 24},
+		{name: "allowedMissings=3", allowedMissings: 3, extendedSampleCount: 27},
+		{name: "allowedMissings=4", allowedMissings: 4, extendedSampleCount: 29},
+		{name: "allowedMissings=5", allowedMissings: 5, extendedSampleCount: 32},
+		{name: "allowedMissings=6", allowedMissings: 6, extendedSampleCount: 35},
+		{name: "allowedMissings=7", allowedMissings: 7, extendedSampleCount: 37},
+		{name: "allowedMissings=8", allowedMissings: 8, extendedSampleCount: 40},
+		{name: "allowedMissings=9", allowedMissings: 9, extendedSampleCount: 42},
+		{name: "allowedMissings=10", allowedMissings: 10, extendedSampleCount: 44},
+		{name: "allowedMissings=11", allowedMissings: 11, extendedSampleCount: 47},
+		{name: "allowedMissings=12", allowedMissings: 12, extendedSampleCount: 49},
+		{name: "allowedMissings=13", allowedMissings: 13, extendedSampleCount: 51},
+		{name: "allowedMissings=14", allowedMissings: 14, extendedSampleCount: 53},
+		{name: "allowedMissings=15", allowedMissings: 15, extendedSampleCount: 55},
+		{name: "allowedMissings=16", allowedMissings: 16, extendedSampleCount: 57},
+		{name: "allowedMissings=17", allowedMissings: 17, extendedSampleCount: 59},
+		{name: "allowedMissings=18", allowedMissings: 18, extendedSampleCount: 61},
+		{name: "allowedMissings=19", allowedMissings: 19, extendedSampleCount: 63},
+		{name: "allowedMissings=20", allowedMissings: 20, extendedSampleCount: 65},
+	}
+
+	for _, tc := range testCases {
+		t.Run(tc.name, func(t *testing.T) {
+			result := peerdas.ExtendedSampleCount(samplesPerSlot, tc.allowedMissings)
+			require.Equal(t, tc.extendedSampleCount, result)
+		})
+	}
+}
+
+func TestHypergeomCDF(t *testing.T) {
+	// Test case from https://en.wikipedia.org/wiki/Hypergeometric_distribution
+	// Population size: 1000, number of successes in population: 500, sample size: 10, number of successes in sample: 5
+	// Expected result: 0.072
+	const (
+		expected = 0.0796665913283742
+		margin   = 0.000001
+	)
+
+	actual := peerdas.HypergeomCDF(5, 128, 65, 16)
+	require.Equal(t, true, expected-margin <= actual && actual <= expected+margin)
+}

beacon-chain/core/peerdas/validator_test.go

@@ -44,7 +44,7 @@ func TestValidatorsCustodyRequirement(t *testing.T) {
 				validatorsIndex[primitives.ValidatorIndex(i)] = true
 			}
 
-			beaconState, err := state_native.InitializeFromProtoFulu(&ethpb.BeaconStateElectra{Validators: validators})
+			beaconState, err := state_native.InitializeFromProtoFulu(&ethpb.BeaconStateFulu{Validators: validators})
 			require.NoError(t, err)
 
 			actual, err := peerdas.ValidatorsCustodyRequirement(beaconState, validatorsIndex)

beacon-chain/core/time/slot_epoch.go

@@ -53,6 +53,11 @@ func HigherEqualThanAltairVersionAndEpoch(s state.BeaconState, e primitives.Epoc
 	return s.Version() >= version.Altair && e >= params.BeaconConfig().AltairForkEpoch
 }
 
+// PeerDASIsActive checks whether peerDAS is active at the provided slot.
+func PeerDASIsActive(slot primitives.Slot) bool {
+	return params.FuluEnabled() && slots.ToEpoch(slot) >= params.BeaconConfig().FuluForkEpoch
+}
+
 // CanUpgradeToAltair returns true if the input `slot` can upgrade to Altair.
 // Spec code:
 // If state.slot % SLOTS_PER_EPOCH == 0 and compute_epoch_at_slot(state.slot) == ALTAIR_FORK_EPOCH

beacon-chain/core/transition/transition.go

@@ -303,7 +303,11 @@ func ProcessSlotsCore(ctx context.Context, span trace.Span, state state.BeaconSt
 func ProcessEpoch(ctx context.Context, state state.BeaconState) (state.BeaconState, error) {
 	var err error
 	if time.CanProcessEpoch(state) {
-		if state.Version() >= version.Electra {
+		if state.Version() >= version.Fulu {
+			if err = fulu.ProcessEpoch(ctx, state); err != nil {
+				return nil, errors.Wrap(err, fmt.Sprintf("could not process %s epoch", version.String(state.Version())))
+			}
+		} else if state.Version() >= version.Electra {
 			if err = electra.ProcessEpoch(ctx, state); err != nil {
 				return nil, errors.Wrap(err, fmt.Sprintf("could not process %s epoch", version.String(state.Version())))
 			}
@@ -377,7 +381,7 @@ func UpgradeState(ctx context.Context, state state.BeaconState) (state.BeaconSta
 	}
 
 	if time.CanUpgradeToFulu(slot) {
-		state, err = fulu.UpgradeToFulu(state)
+		state, err = fulu.UpgradeToFulu(ctx, state)
 		if err != nil {
 			tracing.AnnotateError(span, err)
 			return nil, err

beacon-chain/das/BUILD.bazel

@@ -4,21 +4,26 @@ go_library(
     name = "go_default_library",
     srcs = [
         "availability.go",
+        "availability_columns.go",
         "cache.go",
+        "data_column_cache.go",
         "iface.go",
         "mock.go",
     ],
     importpath = "github.com/OffchainLabs/prysm/v6/beacon-chain/das",
     visibility = ["//visibility:public"],
     deps = [
+        "//beacon-chain/core/peerdas:go_default_library",
         "//beacon-chain/db/filesystem: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",
         "//runtime/logging:go_default_library",
         "//runtime/version:go_default_library",
         "//time/slots:go_default_library",
+        "@com_github_ethereum_go_ethereum//p2p/enode:go_default_library",
         "@com_github_pkg_errors//:go_default_library",
         "@com_github_sirupsen_logrus//:go_default_library",
     ],
@@ -27,13 +32,18 @@ go_library(
 go_test(
     name = "go_default_test",
     srcs = [
+        "availability_columns_test.go",
         "availability_test.go",
         "cache_test.go",
+        "data_column_cache_test.go",
     ],
     embed = [":go_default_library"],
     deps = [
+        "//beacon-chain/core/peerdas:go_default_library",
         "//beacon-chain/db/filesystem:go_default_library",
         "//beacon-chain/verification: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",
         "//consensus-types/primitives:go_default_library",
@@ -41,6 +51,7 @@ go_test(
         "//testing/require:go_default_library",
         "//testing/util:go_default_library",
         "//time/slots:go_default_library",
+        "@com_github_ethereum_go_ethereum//p2p/enode:go_default_library",
         "@com_github_pkg_errors//:go_default_library",
     ],
 )

beacon-chain/das/availability.go

@@ -53,10 +53,16 @@ func NewLazilyPersistentStore(store *filesystem.BlobStorage, verifier BlobBatchV
 // Persist adds blobs to the working blob cache. Blobs stored in this cache will be persisted
 // for at least as long as the node is running. Once IsDataAvailable succeeds, all blobs referenced
 // by the given block are guaranteed to be persisted for the remainder of the retention period.
-func (s *LazilyPersistentStore) Persist(current primitives.Slot, sc ...blocks.ROBlob) error {
-	if len(sc) == 0 {
+func (s *LazilyPersistentStore) Persist(current primitives.Slot, scg ...blocks.ROSidecar) error {
+	if len(scg) == 0 {
 		return nil
 	}
+
+	sc, err := blocks.BlobSidecarsFromSidecars(scg)
+	if err != nil {
+		return errors.Wrap(err, "blob sidecars from sidecars")
+	}
+
 	if len(sc) > 1 {
 		first := sc[0].BlockRoot()
 		for i := 1; i < len(sc); i++ {

beacon-chain/das/availability_columns.go

@@ -0,0 +1,200 @@
+package das
+
+import (
+	"context"
+
+	"github.com/OffchainLabs/prysm/v6/beacon-chain/core/peerdas"
+	"github.com/OffchainLabs/prysm/v6/beacon-chain/db/filesystem"
+	"github.com/OffchainLabs/prysm/v6/beacon-chain/verification"
+	"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/runtime/version"
+	"github.com/OffchainLabs/prysm/v6/time/slots"
+	"github.com/ethereum/go-ethereum/p2p/enode"
+	errors "github.com/pkg/errors"
+)
+
+// LazilyPersistentStoreColumn is an implementation of AvailabilityStore to be used when batch syncing data columns.
+// This implementation will hold any data columns passed to Persist until the IsDataAvailable is called for their
+// block, at which time they will undergo full verification and be saved to the disk.
+type LazilyPersistentStoreColumn struct {
+	store                  *filesystem.DataColumnStorage
+	nodeID                 enode.ID
+	cache                  *dataColumnCache
+	custodyInfo            *peerdas.CustodyInfo
+	newDataColumnsVerifier verification.NewDataColumnsVerifier
+}
+
+var _ AvailabilityStore = &LazilyPersistentStoreColumn{}
+
+// DataColumnsVerifier enables LazilyPersistentStoreColumn to manage the verification process
+// going from RODataColumn->VerifiedRODataColumn, while avoiding the decision of which individual verifications
+// to run and in what order. Since LazilyPersistentStoreColumn always tries to verify and save data columns only when
+// they are all available, the interface takes a slice of data column sidecars.
+type DataColumnsVerifier interface {
+	VerifiedRODataColumns(ctx context.Context, blk blocks.ROBlock, scs []blocks.RODataColumn) ([]blocks.VerifiedRODataColumn, error)
+}
+
+func NewLazilyPersistentStoreColumn(store *filesystem.DataColumnStorage, nodeID enode.ID, newDataColumnsVerifier verification.NewDataColumnsVerifier, custodyInfo *peerdas.CustodyInfo) *LazilyPersistentStoreColumn {
+	return &LazilyPersistentStoreColumn{
+		store:                  store,
+		nodeID:                 nodeID,
+		cache:                  newDataColumnCache(),
+		custodyInfo:            custodyInfo,
+		newDataColumnsVerifier: newDataColumnsVerifier,
+	}
+}
+
+// PersistColumns adds columns to the working column cache. Columns stored in this cache will be persisted
+// for at least as long as the node is running. Once IsDataAvailable succeeds, all columns referenced
+// by the given block are guaranteed to be persisted for the remainder of the retention period.
+func (s *LazilyPersistentStoreColumn) Persist(current primitives.Slot, sidecars ...blocks.ROSidecar) error {
+	if len(sidecars) == 0 {
+		return nil
+	}
+
+	dataColumnSidecars, err := blocks.DataColumnSidecarsFromSidecars(sidecars)
+	if err != nil {
+		return errors.Wrap(err, "blob sidecars from sidecars")
+	}
+
+	// It is safe to retrieve the first sidecar.
+	firstSidecar := dataColumnSidecars[0]
+
+	if len(sidecars) > 1 {
+		firstRoot := firstSidecar.BlockRoot()
+		for _, sidecar := range dataColumnSidecars[1:] {
+			if sidecar.BlockRoot() != firstRoot {
+				return errMixedRoots
+			}
+		}
+	}
+
+	firstSidecarEpoch, currentEpoch := slots.ToEpoch(firstSidecar.Slot()), slots.ToEpoch(current)
+	if !params.WithinDAPeriod(firstSidecarEpoch, currentEpoch) {
+		return nil
+	}
+
+	key := dataColumnCacheKey{slot: firstSidecar.Slot(), root: firstSidecar.BlockRoot()}
+	entry := s.cache.ensure(key)
+
+	for i := range sidecars {
+		if err := entry.stash(&dataColumnSidecars[i]); err != nil {
+			return errors.Wrap(err, "stash DataColumnSidecar")
+		}
+	}
+
+	return nil
+}
+
+// IsDataAvailable returns nil if all the commitments in the given block are persisted to the db and have been verified.
+// DataColumnsSidecars already in the db are assumed to have been previously verified against the block.
+func (s *LazilyPersistentStoreColumn) IsDataAvailable(ctx context.Context, currentSlot primitives.Slot, block blocks.ROBlock) error {
+	blockCommitments, err := s.fullCommitmentsToCheck(s.nodeID, block, currentSlot)
+	if err != nil {
+		return errors.Wrapf(err, "full commitments to check with block root `%#x` and current slot `%d`", block.Root(), currentSlot)
+	}
+
+	// Return early for blocks that do not have any commitments.
+	if blockCommitments.count() == 0 {
+		return nil
+	}
+
+	// Get the root of the block.
+	blockRoot := block.Root()
+
+	// Build the cache key for the block.
+	key := dataColumnCacheKey{slot: block.Block().Slot(), root: blockRoot}
+
+	// Retrieve the cache entry for the block, or create an empty one if it doesn't exist.
+	entry := s.cache.ensure(key)
+
+	// Delete the cache entry for the block at the end.
+	defer s.cache.delete(key)
+
+	// Set the disk summary for the block in the cache entry.
+	entry.setDiskSummary(s.store.Summary(blockRoot))
+
+	// Verify we have all the expected sidecars, and fail fast if any are missing or inconsistent.
+	// We don't try to salvage problematic batches because this indicates a misbehaving peer and we'd rather
+	// ignore their response and decrease their peer score.
+	roDataColumns, err := entry.filter(blockRoot, blockCommitments)
+	if err != nil {
+		return errors.Wrap(err, "filter")
+	}
+
+	// https://github.com/ethereum/consensus-specs/blob/dev/specs/fulu/p2p-interface.md#datacolumnsidecarsbyrange-v1
+	verifier := s.newDataColumnsVerifier(roDataColumns, verification.ByRangeRequestDataColumnSidecarRequirements)
+
+	if err := verifier.ValidFields(); err != nil {
+		return errors.Wrap(err, "valid")
+	}
+
+	if err := verifier.SidecarInclusionProven(); err != nil {
+		return errors.Wrap(err, "sidecar inclusion proven")
+	}
+
+	if err := verifier.SidecarKzgProofVerified(); err != nil {
+		return errors.Wrap(err, "sidecar KZG proof verified")
+	}
+
+	verifiedRoDataColumns, err := verifier.VerifiedRODataColumns()
+	if err != nil {
+		return errors.Wrap(err, "verified RO data columns - should never happen")
+	}
+
+	if err := s.store.Save(verifiedRoDataColumns); err != nil {
+		return errors.Wrap(err, "save data column sidecars")
+	}
+
+	return nil
+}
+
+// fullCommitmentsToCheck returns the commitments to check for a given block.
+func (s *LazilyPersistentStoreColumn) fullCommitmentsToCheck(nodeID enode.ID, block blocks.ROBlock, currentSlot primitives.Slot) (*safeCommitmentsArray, error) {
+	// Return early for blocks that are pre-Fulu.
+	if block.Version() < version.Fulu {
+		return &safeCommitmentsArray{}, nil
+	}
+
+	// Compute the block epoch.
+	blockSlot := block.Block().Slot()
+	blockEpoch := slots.ToEpoch(blockSlot)
+
+	// Compute the current spoch.
+	currentEpoch := slots.ToEpoch(currentSlot)
+
+	// Return early if the request is out of the MIN_EPOCHS_FOR_DATA_COLUMN_SIDECARS_REQUESTS window.
+	if !params.WithinDAPeriod(blockEpoch, currentEpoch) {
+		return &safeCommitmentsArray{}, nil
+	}
+
+	// Retrieve the KZG commitments for the block.
+	kzgCommitments, err := block.Block().Body().BlobKzgCommitments()
+	if err != nil {
+		return nil, errors.Wrap(err, "blob KZG commitments")
+	}
+
+	// Return early if there are no commitments in the block.
+	if len(kzgCommitments) == 0 {
+		return &safeCommitmentsArray{}, nil
+	}
+
+	// Retrieve the groups count.
+	custodyGroupCount := s.custodyInfo.ActualGroupCount()
+
+	// Retrieve peer info.
+	peerInfo, _, err := peerdas.Info(nodeID, custodyGroupCount)
+	if err != nil {
+		return nil, errors.Wrap(err, "peer info")
+	}
+
+	// Create a safe commitments array for the custody columns.
+	commitmentsArray := &safeCommitmentsArray{}
+	for column := range peerInfo.CustodyColumns {
+		commitmentsArray[column] = kzgCommitments
+	}
+
+	return commitmentsArray, nil
+}

beacon-chain/das/availability_columns_test.go

@@ -0,0 +1,303 @@
+package das
+
+import (
+	"context"
+	"testing"
+
+	"github.com/OffchainLabs/prysm/v6/beacon-chain/core/peerdas"
+	"github.com/OffchainLabs/prysm/v6/beacon-chain/db/filesystem"
+	"github.com/OffchainLabs/prysm/v6/beacon-chain/verification"
+	"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"
+	"github.com/OffchainLabs/prysm/v6/consensus-types/primitives"
+	"github.com/OffchainLabs/prysm/v6/encoding/bytesutil"
+	"github.com/OffchainLabs/prysm/v6/testing/require"
+	"github.com/OffchainLabs/prysm/v6/testing/util"
+	"github.com/OffchainLabs/prysm/v6/time/slots"
+	"github.com/ethereum/go-ethereum/p2p/enode"
+)
+
+func roSidecarsFromDataColumnParamsByBlockRoot(t *testing.T, dataColumnParamsByBlockRoot verification.DataColumnsParamsByRoot) ([]blocks.ROSidecar, []blocks.RODataColumn) {
+	roDataColumns, _ := verification.CreateTestVerifiedRoDataColumnSidecars(t, dataColumnParamsByBlockRoot)
+
+	roSidecars := make([]blocks.ROSidecar, 0, len(roDataColumns))
+	for _, roDataColumn := range roDataColumns {
+		roSidecars = append(roSidecars, blocks.NewSidecarFromDataColumnSidecar(roDataColumn))
+	}
+
+	return roSidecars, roDataColumns
+}
+
+func newSignedRoBlock(t *testing.T, signedBeaconBlock interface{}) blocks.ROBlock {
+	sb, err := blocks.NewSignedBeaconBlock(signedBeaconBlock)
+	require.NoError(t, err)
+
+	rb, err := blocks.NewROBlock(sb)
+	require.NoError(t, err)
+
+	return rb
+}
+
+var commitments = [][]byte{
+	bytesutil.PadTo([]byte("a"), 48),
+	bytesutil.PadTo([]byte("b"), 48),
+	bytesutil.PadTo([]byte("c"), 48),
+	bytesutil.PadTo([]byte("d"), 48),
+}
+
+func TestPersist(t *testing.T) {
+	t.Run("no sidecars", func(t *testing.T) {
+		dataColumnStorage := filesystem.NewEphemeralDataColumnStorage(t)
+		lazilyPersistentStoreColumns := NewLazilyPersistentStoreColumn(dataColumnStorage, enode.ID{}, nil, &peerdas.CustodyInfo{})
+		err := lazilyPersistentStoreColumns.Persist(0)
+		require.NoError(t, err)
+		require.Equal(t, 0, len(lazilyPersistentStoreColumns.cache.entries))
+	})
+
+	t.Run("mixed roots", func(t *testing.T) {
+		dataColumnStorage := filesystem.NewEphemeralDataColumnStorage(t)
+
+		dataColumnParamsByBlockRoot := map[[fieldparams.RootLength]byte][]verification.DataColumnParams{
+			{1}: {{ColumnIndex: 1}},
+			{2}: {{ColumnIndex: 2}},
+		}
+
+		roSidecars, _ := roSidecarsFromDataColumnParamsByBlockRoot(t, dataColumnParamsByBlockRoot)
+		lazilyPersistentStoreColumns := NewLazilyPersistentStoreColumn(dataColumnStorage, enode.ID{}, nil, &peerdas.CustodyInfo{})
+
+		err := lazilyPersistentStoreColumns.Persist(0, roSidecars...)
+		require.ErrorIs(t, err, errMixedRoots)
+		require.Equal(t, 0, len(lazilyPersistentStoreColumns.cache.entries))
+	})
+
+	t.Run("outside DA period", func(t *testing.T) {
+		dataColumnStorage := filesystem.NewEphemeralDataColumnStorage(t)
+
+		dataColumnParamsByBlockRoot := map[[fieldparams.RootLength]byte][]verification.DataColumnParams{
+			{1}: {{ColumnIndex: 1}},
+		}
+
+		roSidecars, _ := roSidecarsFromDataColumnParamsByBlockRoot(t, dataColumnParamsByBlockRoot)
+		lazilyPersistentStoreColumns := NewLazilyPersistentStoreColumn(dataColumnStorage, enode.ID{}, nil, &peerdas.CustodyInfo{})
+
+		err := lazilyPersistentStoreColumns.Persist(1_000_000, roSidecars...)
+		require.NoError(t, err)
+		require.Equal(t, 0, len(lazilyPersistentStoreColumns.cache.entries))
+	})
+
+	t.Run("nominal", func(t *testing.T) {
+		dataColumnStorage := filesystem.NewEphemeralDataColumnStorage(t)
+
+		dataColumnParamsByBlockRoot := map[[fieldparams.RootLength]byte][]verification.DataColumnParams{
+			{}: {{ColumnIndex: 1}, {ColumnIndex: 5}},
+		}
+
+		roSidecars, roDataColumns := roSidecarsFromDataColumnParamsByBlockRoot(t, dataColumnParamsByBlockRoot)
+		lazilyPersistentStoreColumns := NewLazilyPersistentStoreColumn(dataColumnStorage, enode.ID{}, nil, &peerdas.CustodyInfo{})
+
+		err := lazilyPersistentStoreColumns.Persist(0, roSidecars...)
+		require.NoError(t, err)
+		require.Equal(t, 1, len(lazilyPersistentStoreColumns.cache.entries))
+
+		key := dataColumnCacheKey{slot: 0, root: [32]byte{}}
+		entry := lazilyPersistentStoreColumns.cache.entries[key]
+
+		// A call to Persist does NOT save the sidecars to disk.
+		require.Equal(t, uint64(0), entry.diskSummary.Count())
+
+		require.DeepSSZEqual(t, roDataColumns[0], *entry.scs[1])
+		require.DeepSSZEqual(t, roDataColumns[1], *entry.scs[5])
+
+		for i, roDataColumn := range entry.scs {
+			if map[int]bool{1: true, 5: true}[i] {
+				continue
+			}
+
+			require.IsNil(t, roDataColumn)
+		}
+	})
+}
+
+func TestIsDataAvailable(t *testing.T) {
+	newDataColumnsVerifier := func(dataColumnSidecars []blocks.RODataColumn, _ []verification.Requirement) verification.DataColumnsVerifier {
+		return &mockDataColumnsVerifier{t: t, dataColumnSidecars: dataColumnSidecars}
+	}
+
+	ctx := context.Background()
+
+	t.Run("without commitments", func(t *testing.T) {
+		signedBeaconBlockFulu := util.NewBeaconBlockFulu()
+		signedRoBlock := newSignedRoBlock(t, signedBeaconBlockFulu)
+
+		dataColumnStorage := filesystem.NewEphemeralDataColumnStorage(t)
+		lazilyPersistentStoreColumns := NewLazilyPersistentStoreColumn(dataColumnStorage, enode.ID{}, newDataColumnsVerifier, &peerdas.CustodyInfo{})
+
+		err := lazilyPersistentStoreColumns.IsDataAvailable(ctx, 0 /*current slot*/, signedRoBlock)
+		require.NoError(t, err)
+	})
+
+	t.Run("with commitments", func(t *testing.T) {
+		signedBeaconBlockFulu := util.NewBeaconBlockFulu()
+		signedBeaconBlockFulu.Block.Body.BlobKzgCommitments = commitments
+		signedRoBlock := newSignedRoBlock(t, signedBeaconBlockFulu)
+		root := signedRoBlock.Root()
+
+		dataColumnStorage := filesystem.NewEphemeralDataColumnStorage(t)
+		lazilyPersistentStoreColumns := NewLazilyPersistentStoreColumn(dataColumnStorage, enode.ID{}, newDataColumnsVerifier, &peerdas.CustodyInfo{})
+
+		indices := [...]uint64{1, 17, 87, 102}
+		dataColumnsParams := make([]verification.DataColumnParams, 0, len(indices))
+		for _, index := range indices {
+			dataColumnParams := verification.DataColumnParams{
+				ColumnIndex:    index,
+				KzgCommitments: commitments,
+			}
+
+			dataColumnsParams = append(dataColumnsParams, dataColumnParams)
+		}
+
+		dataColumnsParamsByBlockRoot := verification.DataColumnsParamsByRoot{root: dataColumnsParams}
+		_, verifiedRoDataColumns := verification.CreateTestVerifiedRoDataColumnSidecars(t, dataColumnsParamsByBlockRoot)
+
+		key := dataColumnCacheKey{root: root}
+		entry := lazilyPersistentStoreColumns.cache.ensure(key)
+		defer lazilyPersistentStoreColumns.cache.delete(key)
+
+		for _, verifiedRoDataColumn := range verifiedRoDataColumns {
+			err := entry.stash(&verifiedRoDataColumn.RODataColumn)
+			require.NoError(t, err)
+		}
+
+		err := lazilyPersistentStoreColumns.IsDataAvailable(ctx, 0 /*current slot*/, signedRoBlock)
+		require.NoError(t, err)
+
+		actual, err := dataColumnStorage.Get(root, indices[:])
+		require.NoError(t, err)
+
+		summary := dataColumnStorage.Summary(root)
+		require.Equal(t, uint64(len(indices)), summary.Count())
+		require.DeepSSZEqual(t, verifiedRoDataColumns, actual)
+	})
+}
+
+func TestFullCommitmentsToCheck(t *testing.T) {
+	windowSlots, err := slots.EpochEnd(params.BeaconConfig().MinEpochsForDataColumnSidecarsRequest)
+	require.NoError(t, err)
+
+	testCases := []struct {
+		name        string
+		commitments [][]byte
+		block       func(*testing.T) blocks.ROBlock
+		slot        primitives.Slot
+	}{
+		{
+			name: "Pre-Fulu block",
+			block: func(t *testing.T) blocks.ROBlock {
+				return newSignedRoBlock(t, util.NewBeaconBlockElectra())
+			},
+		},
+		{
+			name: "Commitments outside data availability window",
+			block: func(t *testing.T) blocks.ROBlock {
+				beaconBlockElectra := util.NewBeaconBlockElectra()
+
+				// Block is from slot 0, "current slot" is window size +1 (so outside the window)
+				beaconBlockElectra.Block.Body.BlobKzgCommitments = commitments
+
+				return newSignedRoBlock(t, beaconBlockElectra)
+			},
+			slot: windowSlots + 1,
+		},
+		{
+			name: "Commitments within data availability window",
+			block: func(t *testing.T) blocks.ROBlock {
+				signedBeaconBlockFulu := util.NewBeaconBlockFulu()
+				signedBeaconBlockFulu.Block.Body.BlobKzgCommitments = commitments
+				signedBeaconBlockFulu.Block.Slot = 100
+
+				return newSignedRoBlock(t, signedBeaconBlockFulu)
+			},
+			commitments: commitments,
+			slot:        100,
+		},
+	}
+
+	for _, tc := range testCases {
+		t.Run(tc.name, func(t *testing.T) {
+			resetFlags := flags.Get()
+			gFlags := new(flags.GlobalFlags)
+			gFlags.SubscribeAllDataSubnets = true
+			flags.Init(gFlags)
+			defer flags.Init(resetFlags)
+
+			b := tc.block(t)
+			s := NewLazilyPersistentStoreColumn(nil, enode.ID{}, nil, &peerdas.CustodyInfo{})
+
+			commitmentsArray, err := s.fullCommitmentsToCheck(enode.ID{}, b, tc.slot)
+			require.NoError(t, err)
+
+			for _, commitments := range commitmentsArray {
+				require.DeepEqual(t, tc.commitments, commitments)
+			}
+		})
+	}
+}
+
+type mockDataColumnsVerifier struct {
+	t                                                                        *testing.T
+	dataColumnSidecars                                                       []blocks.RODataColumn
+	validCalled, SidecarInclusionProvenCalled, SidecarKzgProofVerifiedCalled bool
+}
+
+var _ verification.DataColumnsVerifier = &mockDataColumnsVerifier{}
+
+func (m *mockDataColumnsVerifier) VerifiedRODataColumns() ([]blocks.VerifiedRODataColumn, error) {
+	require.Equal(m.t, true, m.validCalled && m.SidecarInclusionProvenCalled && m.SidecarKzgProofVerifiedCalled)
+
+	verifiedDataColumnSidecars := make([]blocks.VerifiedRODataColumn, 0, len(m.dataColumnSidecars))
+	for _, dataColumnSidecar := range m.dataColumnSidecars {
+		verifiedDataColumnSidecar := blocks.NewVerifiedRODataColumn(dataColumnSidecar)
+		verifiedDataColumnSidecars = append(verifiedDataColumnSidecars, verifiedDataColumnSidecar)
+	}
+
+	return verifiedDataColumnSidecars, nil
+}
+
+func (m *mockDataColumnsVerifier) SatisfyRequirement(verification.Requirement) {}
+
+func (m *mockDataColumnsVerifier) ValidFields() error {
+	m.validCalled = true
+	return nil
+}
+
+func (m *mockDataColumnsVerifier) CorrectSubnet(dataColumnSidecarSubTopic string, expectedTopics []string) error {
+	return nil
+}
+func (m *mockDataColumnsVerifier) NotFromFutureSlot() error                         { return nil }
+func (m *mockDataColumnsVerifier) SlotAboveFinalized() error                        { return nil }
+func (m *mockDataColumnsVerifier) ValidProposerSignature(ctx context.Context) error { return nil }
+
+func (m *mockDataColumnsVerifier) SidecarParentSeen(parentSeen func([fieldparams.RootLength]byte) bool) error {
+	return nil
+}
+
+func (m *mockDataColumnsVerifier) SidecarParentValid(badParent func([fieldparams.RootLength]byte) bool) error {
+	return nil
+}
+
+func (m *mockDataColumnsVerifier) SidecarParentSlotLower() error       { return nil }
+func (m *mockDataColumnsVerifier) SidecarDescendsFromFinalized() error { return nil }
+
+func (m *mockDataColumnsVerifier) SidecarInclusionProven() error {
+	m.SidecarInclusionProvenCalled = true
+	return nil
+}
+
+func (m *mockDataColumnsVerifier) SidecarKzgProofVerified() error {
+	m.SidecarKzgProofVerifiedCalled = true
+	return nil
+}
+
+func (m *mockDataColumnsVerifier) SidecarProposerExpected(ctx context.Context) error { return nil }

beacon-chain/das/availability_test.go

@@ -116,9 +116,11 @@ func TestLazilyPersistent_Missing(t *testing.T) {
 	ctx := context.Background()
 	store := filesystem.NewEphemeralBlobStorage(t)
 
-	blk, scs := util.GenerateTestDenebBlockWithSidecar(t, [32]byte{}, 1, 3)
+	blk, blobSidecars := util.GenerateTestDenebBlockWithSidecar(t, [32]byte{}, 1, 3)
 
-	mbv := &mockBlobBatchVerifier{t: t, scs: scs}
+	scs := blocks.NewSidecarsFromBlobSidecars(blobSidecars)
+
+	mbv := &mockBlobBatchVerifier{t: t, scs: blobSidecars}
 	as := NewLazilyPersistentStore(store, mbv)
 
 	// Only one commitment persisted, should return error with other indices
@@ -141,12 +143,14 @@ func TestLazilyPersistent_Mismatch(t *testing.T) {
 	ctx := context.Background()
 	store := filesystem.NewEphemeralBlobStorage(t)
 
-	blk, scs := util.GenerateTestDenebBlockWithSidecar(t, [32]byte{}, 1, 3)
+	blk, blobSidecars := util.GenerateTestDenebBlockWithSidecar(t, [32]byte{}, 1, 3)
 
 	mbv := &mockBlobBatchVerifier{t: t, err: errors.New("kzg check should not run")}
-	scs[0].KzgCommitment = bytesutil.PadTo([]byte("nope"), 48)
+	blobSidecars[0].KzgCommitment = bytesutil.PadTo([]byte("nope"), 48)
 	as := NewLazilyPersistentStore(store, mbv)
 
+	scs := blocks.NewSidecarsFromBlobSidecars(blobSidecars)
+
 	// Only one commitment persisted, should return error with other indices
 	require.NoError(t, as.Persist(1, scs[0]))
 	err := as.IsDataAvailable(ctx, 1, blk)
@@ -155,7 +159,10 @@ func TestLazilyPersistent_Mismatch(t *testing.T) {
 }
 
 func TestLazyPersistOnceCommitted(t *testing.T) {
-	_, scs := util.GenerateTestDenebBlockWithSidecar(t, [32]byte{}, 1, 6)
+	_, blobSidecars := util.GenerateTestDenebBlockWithSidecar(t, [32]byte{}, 1, 6)
+
+	scs := blocks.NewSidecarsFromBlobSidecars(blobSidecars)
+
 	as := NewLazilyPersistentStore(filesystem.NewEphemeralBlobStorage(t), &mockBlobBatchVerifier{})
 	// stashes as expected
 	require.NoError(t, as.Persist(1, scs...))
@@ -163,10 +170,13 @@ func TestLazyPersistOnceCommitted(t *testing.T) {
 	require.ErrorIs(t, as.Persist(1, scs...), ErrDuplicateSidecar)
 
 	// ignores index out of bound
-	scs[0].Index = 6
-	require.ErrorIs(t, as.Persist(1, scs[0]), errIndexOutOfBounds)
+	blobSidecars[0].Index = 6
+	require.ErrorIs(t, as.Persist(1, blocks.NewSidecarFromBlobSidecar(blobSidecars[0])), errIndexOutOfBounds)
+
+	_, moreBlobSidecars := util.GenerateTestDenebBlockWithSidecar(t, [32]byte{}, 1, 4)
+
+	more := blocks.NewSidecarsFromBlobSidecars(moreBlobSidecars)
 
-	_, more := util.GenerateTestDenebBlockWithSidecar(t, [32]byte{}, 1, 4)
 	// ignores sidecars before the retention period
 	slotOOB, err := slots.EpochStart(params.BeaconConfig().MinEpochsForBlobsSidecarsRequest)
 	require.NoError(t, err)

beacon-chain/das/cache.go

@@ -10,12 +10,7 @@ import (
 	"github.com/pkg/errors"
 )
 
-var (
-	ErrDuplicateSidecar   = errors.New("duplicate sidecar stashed in AvailabilityStore")
-	errIndexOutOfBounds   = errors.New("sidecar.index > MAX_BLOBS_PER_BLOCK")
-	errCommitmentMismatch = errors.New("KzgCommitment of sidecar in cache did not match block commitment")
-	errMissingSidecar     = errors.New("no sidecar in cache for block commitment")
-)
+var errIndexOutOfBounds = errors.New("sidecar.index > MAX_BLOBS_PER_BLOCK")
 
 // cacheKey includes the slot so that we can easily iterate through the cache and compare
 // slots for eviction purposes. Whether the input is the block or the sidecar, we always have

beacon-chain/das/data_column_cache.go

@@ -0,0 +1,135 @@
+package das
+
+import (
+	"reflect"
+
+	"github.com/OffchainLabs/prysm/v6/beacon-chain/db/filesystem"
+	fieldparams "github.com/OffchainLabs/prysm/v6/config/fieldparams"
+	"github.com/OffchainLabs/prysm/v6/consensus-types/blocks"
+	"github.com/OffchainLabs/prysm/v6/consensus-types/primitives"
+	"github.com/pkg/errors"
+)
+
+var (
+	ErrDuplicateSidecar   = errors.New("duplicate sidecar stashed in AvailabilityStore")
+	errColumnIndexTooHigh = errors.New("column index too high")
+	errCommitmentMismatch = errors.New("KzgCommitment of sidecar in cache did not match block commitment")
+	errMissingSidecar     = errors.New("no sidecar in cache for block commitment")
+)
+
+// dataColumnCacheKey includes the slot so that we can easily iterate through the cache and compare
+// slots for eviction purposes. Whether the input is the block or the sidecar, we always have
+// the root+slot when interacting with the cache, so it isn't an inconvenience to use both.
+type dataColumnCacheKey struct {
+	slot primitives.Slot
+	root [32]byte
+}
+
+type dataColumnCache struct {
+	entries map[dataColumnCacheKey]*dataColumnCacheEntry
+}
+
+func newDataColumnCache() *dataColumnCache {
+	return &dataColumnCache{entries: make(map[dataColumnCacheKey]*dataColumnCacheEntry)}
+}
+
+// ensure returns the entry for the given key, creating it if it isn't already present.
+func (c *dataColumnCache) ensure(key dataColumnCacheKey) *dataColumnCacheEntry {
+	entry, ok := c.entries[key]
+	if !ok {
+		entry = &dataColumnCacheEntry{}
+		c.entries[key] = entry
+	}
+
+	return entry
+}
+
+// delete removes the cache entry from the cache.
+func (c *dataColumnCache) delete(key dataColumnCacheKey) {
+	delete(c.entries, key)
+}
+
+// dataColumnCacheEntry holds a fixed-length cache of BlobSidecars.
+type dataColumnCacheEntry struct {
+	scs         [fieldparams.NumberOfColumns]*blocks.RODataColumn
+	diskSummary filesystem.DataColumnStorageSummary
+}
+
+func (e *dataColumnCacheEntry) setDiskSummary(sum filesystem.DataColumnStorageSummary) {
+	e.diskSummary = sum
+}
+
+// stash adds an item to the in-memory cache of DataColumnSidecars.
+// Only the first DataColumnSidecar of a given Index will be kept in the cache.
+// stash will return an error if the given data colunn is already in the cache, or if the Index is out of bounds.
+func (e *dataColumnCacheEntry) stash(sc *blocks.RODataColumn) error {
+	if sc.Index >= fieldparams.NumberOfColumns {
+		return errors.Wrapf(errColumnIndexTooHigh, "index=%d", sc.Index)
+	}
+
+	if e.scs[sc.Index] != nil {
+		return errors.Wrapf(ErrDuplicateSidecar, "root=%#x, index=%d, commitment=%#x", sc.BlockRoot(), sc.Index, sc.KzgCommitments)
+	}
+
+	e.scs[sc.Index] = sc
+
+	return nil
+}
+
+func (e *dataColumnCacheEntry) filter(root [32]byte, commitmentsArray *safeCommitmentsArray) ([]blocks.RODataColumn, error) {
+	nonEmptyIndices := commitmentsArray.nonEmptyIndices()
+	if e.diskSummary.AllAvailable(nonEmptyIndices) {
+		return nil, nil
+	}
+
+	commitmentsCount := commitmentsArray.count()
+	sidecars := make([]blocks.RODataColumn, 0, commitmentsCount)
+
+	for i := range nonEmptyIndices {
+		if e.diskSummary.HasIndex(i) {
+			continue
+		}
+
+		if e.scs[i] == nil {
+			return nil, errors.Wrapf(errMissingSidecar, "root=%#x, index=%#x", root, i)
+		}
+
+		if !reflect.DeepEqual(commitmentsArray[i], e.scs[i].KzgCommitments) {
+			return nil, errors.Wrapf(errCommitmentMismatch, "root=%#x, index=%#x, commitment=%#x, block commitment=%#x", root, i, e.scs[i].KzgCommitments, commitmentsArray[i])
+		}
+
+		sidecars = append(sidecars, *e.scs[i])
+	}
+
+	return sidecars, nil
+}
+
+// safeCommitmentsArray is a fixed size array of commitments.
+// This is helpful for avoiding gratuitous bounds checks.
+type safeCommitmentsArray [fieldparams.NumberOfColumns][][]byte
+
+// count returns the number of commitments in the array.
+func (s *safeCommitmentsArray) count() int {
+	count := 0
+
+	for i := range s {
+		if s[i] != nil {
+			count++
+		}
+	}
+
+	return count
+}
+
+// nonEmptyIndices returns a map of indices that are non-nil in the array.
+func (s *safeCommitmentsArray) nonEmptyIndices() map[uint64]bool {
+	columns := make(map[uint64]bool)
+
+	for i := range s {
+		if s[i] != nil {
+			columns[uint64(i)] = true
+		}
+	}
+
+	return columns
+}

beacon-chain/das/data_column_cache_test.go

@@ -0,0 +1,124 @@
+package das
+
+import (
+	"testing"
+
+	"github.com/OffchainLabs/prysm/v6/beacon-chain/db/filesystem"
+	"github.com/OffchainLabs/prysm/v6/beacon-chain/verification"
+	fieldparams "github.com/OffchainLabs/prysm/v6/config/fieldparams"
+	"github.com/OffchainLabs/prysm/v6/consensus-types/blocks"
+	"github.com/OffchainLabs/prysm/v6/testing/require"
+)
+
+func TestEnsureDeleteSetDiskSummary(t *testing.T) {
+	c := newDataColumnCache()
+	key := dataColumnCacheKey{}
+	entry := c.ensure(key)
+	require.DeepEqual(t, dataColumnCacheEntry{}, *entry)
+
+	diskSummary := filesystem.NewDataColumnStorageSummary(42, [fieldparams.NumberOfColumns]bool{true})
+	entry.setDiskSummary(diskSummary)
+	entry = c.ensure(key)
+	require.DeepEqual(t, dataColumnCacheEntry{diskSummary: diskSummary}, *entry)
+
+	c.delete(key)
+	entry = c.ensure(key)
+	require.DeepEqual(t, dataColumnCacheEntry{}, *entry)
+}
+
+func TestStash(t *testing.T) {
+	t.Run("Index too high", func(t *testing.T) {
+		dataColumnParamsByBlockRoot := verification.DataColumnsParamsByRoot{{1}: {{ColumnIndex: 10_000}}}
+		roDataColumns, _ := verification.CreateTestVerifiedRoDataColumnSidecars(t, dataColumnParamsByBlockRoot)
+
+		var entry dataColumnCacheEntry
+		err := entry.stash(&roDataColumns[0])
+		require.NotNil(t, err)
+	})
+
+	t.Run("Nominal and already existing", func(t *testing.T) {
+		dataColumnParamsByBlockRoot := verification.DataColumnsParamsByRoot{{1}: {{ColumnIndex: 1}}}
+		roDataColumns, _ := verification.CreateTestVerifiedRoDataColumnSidecars(t, dataColumnParamsByBlockRoot)
+
+		var entry dataColumnCacheEntry
+		err := entry.stash(&roDataColumns[0])
+		require.NoError(t, err)
+
+		require.DeepEqual(t, roDataColumns[0], entry.scs[1])
+
+		err = entry.stash(&roDataColumns[0])
+		require.NotNil(t, err)
+	})
+}
+
+func TestFilterDataColumns(t *testing.T) {
+	t.Run("All available", func(t *testing.T) {
+		commitmentsArray := safeCommitmentsArray{nil, [][]byte{[]byte{1}}, nil, [][]byte{[]byte{3}}}
+
+		diskSummary := filesystem.NewDataColumnStorageSummary(42, [fieldparams.NumberOfColumns]bool{false, true, false, true})
+
+		dataColumnCacheEntry := dataColumnCacheEntry{diskSummary: diskSummary}
+
+		actual, err := dataColumnCacheEntry.filter([fieldparams.RootLength]byte{}, &commitmentsArray)
+		require.NoError(t, err)
+		require.IsNil(t, actual)
+	})
+
+	t.Run("Some scs missing", func(t *testing.T) {
+		commitmentsArray := safeCommitmentsArray{nil, [][]byte{[]byte{1}}}
+
+		diskSummary := filesystem.NewDataColumnStorageSummary(42, [fieldparams.NumberOfColumns]bool{})
+
+		dataColumnCacheEntry := dataColumnCacheEntry{diskSummary: diskSummary}
+
+		_, err := dataColumnCacheEntry.filter([fieldparams.RootLength]byte{}, &commitmentsArray)
+		require.NotNil(t, err)
+	})
+
+	t.Run("Commitments not equal", func(t *testing.T) {
+		root := [fieldparams.RootLength]byte{}
+		commitmentsArray := safeCommitmentsArray{nil, [][]byte{[]byte{1}}}
+
+		dataColumnParamsByBlockRoot := verification.DataColumnsParamsByRoot{root: {{ColumnIndex: 1}}}
+		roDataColumns, _ := verification.CreateTestVerifiedRoDataColumnSidecars(t, dataColumnParamsByBlockRoot)
+
+		var scs [fieldparams.NumberOfColumns]*blocks.RODataColumn
+		scs[1] = &roDataColumns[0]
+
+		dataColumnCacheEntry := dataColumnCacheEntry{scs: scs}
+
+		_, err := dataColumnCacheEntry.filter(root, &commitmentsArray)
+		require.NotNil(t, err)
+	})
+
+	t.Run("Nominal", func(t *testing.T) {
+		root := [fieldparams.RootLength]byte{}
+		commitmentsArray := safeCommitmentsArray{nil, [][]byte{[]byte{1}}, nil, [][]byte{[]byte{3}}}
+
+		diskSummary := filesystem.NewDataColumnStorageSummary(42, [fieldparams.NumberOfColumns]bool{false, true})
+
+		dataColumnParamsByBlockRoot := verification.DataColumnsParamsByRoot{root: {{ColumnIndex: 3, KzgCommitments: [][]byte{[]byte{3}}}}}
+		expected, _ := verification.CreateTestVerifiedRoDataColumnSidecars(t, dataColumnParamsByBlockRoot)
+
+		var scs [fieldparams.NumberOfColumns]*blocks.RODataColumn
+		scs[3] = &expected[0]
+
+		dataColumnCacheEntry := dataColumnCacheEntry{scs: scs, diskSummary: diskSummary}
+
+		actual, err := dataColumnCacheEntry.filter(root, &commitmentsArray)
+		require.NoError(t, err)
+
+		require.DeepEqual(t, expected, actual)
+	})
+}
+
+func TestCount(t *testing.T) {
+	s := safeCommitmentsArray{nil, [][]byte{[]byte{1}}, nil, [][]byte{[]byte{3}}}
+	require.Equal(t, 2, s.count())
+}
+
+func TestNonEmptyIndices(t *testing.T) {
+	s := safeCommitmentsArray{nil, [][]byte{[]byte{10}}, nil, [][]byte{[]byte{20}}}
+	actual := s.nonEmptyIndices()
+	require.DeepEqual(t, map[uint64]bool{1: true, 3: true}, actual)
+}

beacon-chain/das/iface.go

@@ -15,5 +15,5 @@ import (
 // durably persisted before returning a non-error value.
 type AvailabilityStore interface {
 	IsDataAvailable(ctx context.Context, current primitives.Slot, b blocks.ROBlock) error
-	Persist(current primitives.Slot, sc ...blocks.ROBlob) error
+	Persist(current primitives.Slot, sc ...blocks.ROSidecar) error
 }

beacon-chain/das/mock.go

@@ -5,6 +5,7 @@ import (
 
 	"github.com/OffchainLabs/prysm/v6/consensus-types/blocks"
 	"github.com/OffchainLabs/prysm/v6/consensus-types/primitives"
+	errors "github.com/pkg/errors"
 )
 
 // MockAvailabilityStore is an implementation of AvailabilityStore that can be used by other packages in tests.
@@ -24,9 +25,13 @@ func (m *MockAvailabilityStore) IsDataAvailable(ctx context.Context, current pri
 }
 
 // Persist satisfies the corresponding method of the AvailabilityStore interface in a way that is useful for tests.
-func (m *MockAvailabilityStore) Persist(current primitives.Slot, sc ...blocks.ROBlob) error {
+func (m *MockAvailabilityStore) Persist(current primitives.Slot, sc ...blocks.ROSidecar) error {
+	blobSidecars, err := blocks.BlobSidecarsFromSidecars(sc)
+	if err != nil {
+		return errors.Wrap(err, "blob sidecars from sidecars")
+	}
 	if m.PersistBlobsCallback != nil {
-		return m.PersistBlobsCallback(current, sc...)
+		return m.PersistBlobsCallback(current, blobSidecars...)
 	}
 	return nil
 }

beacon-chain/db/kv/state.go

@@ -518,7 +518,7 @@ func (s *Store) unmarshalState(_ context.Context, enc []byte, validatorEntries [
 
 	switch {
 	case hasFuluKey(enc):
-		protoState := &ethpb.BeaconStateElectra{}
+		protoState := &ethpb.BeaconStateFulu{}
 		if err := protoState.UnmarshalSSZ(enc[len(fuluKey):]); err != nil {
 			return nil, errors.Wrap(err, "failed to unmarshal encoding for Fulu")
 		}
@@ -690,7 +690,7 @@ func marshalState(ctx context.Context, st state.ReadOnlyBeaconState) ([]byte, er
 		}
 		return snappy.Encode(nil, append(ElectraKey, rawObj...)), nil
 	case version.Fulu:
-		rState, ok := st.ToProtoUnsafe().(*ethpb.BeaconStateElectra)
+		rState, ok := st.ToProtoUnsafe().(*ethpb.BeaconStateFulu)
 		if !ok {
 			return nil, errors.New("non valid inner state")
 		}

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 +45,16 @@ var (
 		GetPayloadMethodV3,
 		GetPayloadBodiesByHashV1,
 		GetPayloadBodiesByRangeV1,
+		GetBlobsV1,
 	}
 	electraEngineEndpoints = []string{
 		NewPayloadMethodV4,
 		GetPayloadMethodV4,
 	}
+	fuluEngineEndpoints = []string{
+		GetPayloadMethodV5,
+		GetBlobsV2,
+	}
 )
 
 const (
@@ -73,6 +79,8 @@ 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 +93,21 @@ 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
+	// TODO: Remove temporarily needed hack since geth takes an input blobs txs with blobs proofs, and
+	// does the heavy lifting of building cells proofs, while normally this is done by the tx sender.
+	// This is a cool hack because it lets the CL to act as if the tx sender actually computed the cells proofs.
+	// The only counter part is the `engine_getPayloadv<x>` takes a lot of time.
+	// defaultEngineTimeout = time.Second
+	defaultEngineTimeout = 2 * 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.
@@ -108,6 +126,7 @@ type Reconstructor interface {
 		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)
+	ReconstructDataColumnSidecars(ctx context.Context, block interfaces.ReadOnlySignedBeaconBlock, blockRoot [32]byte) ([]blocks.VerifiedRODataColumn, error)
 }
 
 // EngineCaller defines a client that can interact with an Ethereum
@@ -257,6 +276,9 @@ func (s *Service) ForkchoiceUpdated(
 
 func getPayloadMethodAndMessage(slot primitives.Slot) (string, proto.Message) {
 	pe := slots.ToEpoch(slot)
+	if pe >= params.BeaconConfig().FuluForkEpoch {
+		return GetPayloadMethodV5, &pb.ExecutionBundleFulu{}
+	}
 	if pe >= params.BeaconConfig().ElectraForkEpoch {
 		return GetPayloadMethodV4, &pb.ExecutionBundleElectra{}
 	}
@@ -289,7 +311,7 @@ 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 +320,36 @@ 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, len(supportedEngineEndpoints))
+	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 +520,10 @@ 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 +531,19 @@ 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 +654,73 @@ 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
+	var kzgHashes []common.Hash
+	for _, commitment := range kzgCommitments {
+		kzgHashes = append(kzgHashes, primitives.ConvertKzgCommitmentToVersionedHash(commitment))
+	}
+
+	// Fetch all blobsAndCellsProofs from EL
+	blobAndProofV2s, err := s.GetBlobsV2(ctx, kzgHashes)
+	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 := make([][]byte, 0, len(blobAndProofV2s))
+	cellProofs := make([][]byte, 0, len(blobAndProofV2s))
+	for _, blobsAndProofs := range blobAndProofV2s {
+		if blobsAndProofs == nil {
+			return nil, wrapWithBlockRoot(errMissingBlobsAndProofsFromEL, blockRoot, "")
+		}
+		blobs = append(blobs, blobsAndProofs.Blob)
+		cellProofs = append(cellProofs, blobsAndProofs.KzgProofs...)
+	}
+
+	dataColumnSidecars, err := peerdas.ConstructDataColumnSidecars(signedROBlock, blobs, cellProofs)
+	if err != nil {
+		return nil, wrapWithBlockRoot(err, blockRoot, "construct data column sidecars")
+	}
+
+	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")
+		}
+
+		// We trust the execution layer we are connected to, so we can upgrade the read only data column sidecar into a verified one.
+		verifiedRODataColumn := blocks.NewVerifiedRODataColumn(roDataColumn)
+		verifiedRODataColumns = append(verifiedRODataColumns, verifiedRODataColumn)
+	}
+
+	log.Debug("Data columns successfully reconstructed from EL")
+
+	return verifiedRODataColumns, nil
+}
+
 func fullPayloadFromPayloadBody(
 	header interfaces.ExecutionData, body *pb.ExecutionPayloadBody, bVersion int,
 ) (interfaces.ExecutionData, error) {
@@ -902,3 +1008,8 @@ 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/mock_engine_client.go

@@ -38,6 +38,8 @@ type EngineClient struct {
 	ErrGetPayload               error
 	BlobSidecars                []blocks.VerifiedROBlob
 	ErrorBlobSidecars           error
+	DataColumnSidecars          []blocks.VerifiedRODataColumn
+	ErrorDataColumnSidecars     error
 }
 
 // NewPayload --
@@ -113,6 +115,10 @@ func (e *EngineClient) ReconstructBlobSidecars(context.Context, interfaces.ReadO
 	return e.BlobSidecars, e.ErrorBlobSidecars
 }
 
+func (e *EngineClient) ReconstructDataColumnSidecars(ctx context.Context, block interfaces.ReadOnlySignedBeaconBlock, blockRoot [32]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/BUILD.bazel

@@ -23,6 +23,7 @@ go_library(
         "//beacon-chain/cache:go_default_library",
         "//beacon-chain/cache/depositsnapshot:go_default_library",
         "//beacon-chain/core/light-client: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/db/kv:go_default_library",

beacon-chain/node/node.go

@@ -25,6 +25,7 @@ import (
 	"github.com/OffchainLabs/prysm/v6/beacon-chain/cache"
 	"github.com/OffchainLabs/prysm/v6/beacon-chain/cache/depositsnapshot"
 	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/db/kv"
@@ -86,44 +87,47 @@ type serviceFlagOpts struct {
 // full PoS node. It handles the lifecycle of the entire system and registers
 // services to a service registry.
 type BeaconNode struct {
-	cliCtx                  *cli.Context
-	ctx                     context.Context
-	cancel                  context.CancelFunc
-	services                *runtime.ServiceRegistry
-	lock                    sync.RWMutex
-	stop                    chan struct{} // Channel to wait for termination notifications.
-	db                      db.Database
-	slasherDB               db.SlasherDatabase
-	attestationCache        *cache.AttestationCache
-	attestationPool         attestations.Pool
-	exitPool                voluntaryexits.PoolManager
-	slashingsPool           slashings.PoolManager
-	syncCommitteePool       synccommittee.Pool
-	blsToExecPool           blstoexec.PoolManager
-	depositCache            cache.DepositCache
-	trackedValidatorsCache  *cache.TrackedValidatorsCache
-	payloadIDCache          *cache.PayloadIDCache
-	stateFeed               *event.Feed
-	blockFeed               *event.Feed
-	opFeed                  *event.Feed
-	stateGen                *stategen.State
-	collector               *bcnodeCollector
-	slasherBlockHeadersFeed *event.Feed
-	slasherAttestationsFeed *event.Feed
-	finalizedStateAtStartUp state.BeaconState
-	serviceFlagOpts         *serviceFlagOpts
-	GenesisInitializer      genesis.Initializer
-	CheckpointInitializer   checkpoint.Initializer
-	forkChoicer             forkchoice.ForkChoicer
-	clockWaiter             startup.ClockWaiter
-	BackfillOpts            []backfill.ServiceOption
-	initialSyncComplete     chan struct{}
-	BlobStorage             *filesystem.BlobStorage
-	BlobStorageOptions      []filesystem.BlobStorageOption
-	verifyInitWaiter        *verification.InitializerWaiter
-	syncChecker             *initialsync.SyncChecker
-	slasherEnabled          bool
-	lcStore                 *lightclient.Store
+	cliCtx                   *cli.Context
+	ctx                      context.Context
+	cancel                   context.CancelFunc
+	services                 *runtime.ServiceRegistry
+	lock                     sync.RWMutex
+	stop                     chan struct{} // Channel to wait for termination notifications.
+	db                       db.Database
+	slasherDB                db.SlasherDatabase
+	attestationCache         *cache.AttestationCache
+	attestationPool          attestations.Pool
+	exitPool                 voluntaryexits.PoolManager
+	slashingsPool            slashings.PoolManager
+	syncCommitteePool        synccommittee.Pool
+	blsToExecPool            blstoexec.PoolManager
+	depositCache             cache.DepositCache
+	trackedValidatorsCache   *cache.TrackedValidatorsCache
+	payloadIDCache           *cache.PayloadIDCache
+	stateFeed                *event.Feed
+	blockFeed                *event.Feed
+	opFeed                   *event.Feed
+	stateGen                 *stategen.State
+	collector                *bcnodeCollector
+	slasherBlockHeadersFeed  *event.Feed
+	slasherAttestationsFeed  *event.Feed
+	finalizedStateAtStartUp  state.BeaconState
+	serviceFlagOpts          *serviceFlagOpts
+	GenesisInitializer       genesis.Initializer
+	CheckpointInitializer    checkpoint.Initializer
+	forkChoicer              forkchoice.ForkChoicer
+	clockWaiter              startup.ClockWaiter
+	BackfillOpts             []backfill.ServiceOption
+	initialSyncComplete      chan struct{}
+	BlobStorage              *filesystem.BlobStorage
+	BlobStorageOptions       []filesystem.BlobStorageOption
+	DataColumnStorage        *filesystem.DataColumnStorage
+	DataColumnStorageOptions []filesystem.DataColumnStorageOption
+	custodyInfo              *peerdas.CustodyInfo
+	verifyInitWaiter         *verification.InitializerWaiter
+	syncChecker              *initialsync.SyncChecker
+	slasherEnabled           bool
+	lcStore                  *lightclient.Store
 }
 
 // New creates a new node instance, sets up configuration options, and registers
@@ -161,6 +165,7 @@ func New(cliCtx *cli.Context, cancel context.CancelFunc, opts ...Option) (*Beaco
 		serviceFlagOpts:         &serviceFlagOpts{},
 		initialSyncComplete:     make(chan struct{}),
 		syncChecker:             &initialsync.SyncChecker{},
+		custodyInfo:             &peerdas.CustodyInfo{},
 		slasherEnabled:          cliCtx.Bool(flags.SlasherFlag.Name),
 		lcStore:                 &lightclient.Store{},
 	}
@@ -190,6 +195,15 @@ func New(cliCtx *cli.Context, cancel context.CancelFunc, opts ...Option) (*Beaco
 		beacon.BlobStorage = blobs
 	}
 
+	if beacon.DataColumnStorage == nil {
+		dataColumnStorage, err := filesystem.NewDataColumnStorage(cliCtx.Context, beacon.DataColumnStorageOptions...)
+		if err != nil {
+			return nil, errors.Wrap(err, "new data column storage")
+		}
+
+		beacon.DataColumnStorage = dataColumnStorage
+	}
+
 	bfs, err := startBaseServices(cliCtx, beacon, depositAddress)
 	if err != nil {
 		return nil, errors.Wrap(err, "could not start modules")
@@ -280,7 +294,9 @@ func startBaseServices(cliCtx *cli.Context, beacon *BeaconNode, depositAddress s
 	if err := beacon.startDB(cliCtx, depositAddress); err != nil {
 		return nil, errors.Wrap(err, "could not start DB")
 	}
+
 	beacon.BlobStorage.WarmCache()
+	beacon.DataColumnStorage.WarmCache()
 
 	log.Debugln("Starting Slashing DB")
 	if err := beacon.startSlasherDB(cliCtx); err != nil {
@@ -491,6 +507,10 @@ func (b *BeaconNode) clearDB(clearDB, forceClearDB bool, d *kv.Store, dbPath str
 			return nil, errors.Wrap(err, "could not clear blob storage")
 		}
 
+		if err := b.DataColumnStorage.Clear(); err != nil {
+			return nil, errors.Wrap(err, "could not clear data column storage")
+		}
+
 		d, err = kv.NewKVStore(b.ctx, dbPath)
 		if err != nil {
 			return nil, errors.Wrap(err, "could not create new database")
@@ -697,6 +717,7 @@ func (b *BeaconNode) registerP2P(cliCtx *cli.Context) error {
 		StateNotifier:        b,
 		DB:                   b.db,
 		ClockWaiter:          b.clockWaiter,
+		CustodyInfo:          b.custodyInfo,
 	})
 	if err != nil {
 		return err
@@ -775,9 +796,11 @@ func (b *BeaconNode) registerBlockchainService(fc forkchoice.ForkChoicer, gs *st
 		blockchain.WithClockSynchronizer(gs),
 		blockchain.WithSyncComplete(syncComplete),
 		blockchain.WithBlobStorage(b.BlobStorage),
+		blockchain.WithDataColumnStorage(b.DataColumnStorage),
 		blockchain.WithTrackedValidatorsCache(b.trackedValidatorsCache),
 		blockchain.WithPayloadIDCache(b.payloadIDCache),
 		blockchain.WithSyncChecker(b.syncChecker),
+		blockchain.WithCustodyInfo(b.custodyInfo),
 		blockchain.WithSlasherEnabled(b.slasherEnabled),
 		blockchain.WithLightClientStore(b.lcStore),
 	)
@@ -862,8 +885,11 @@ func (b *BeaconNode) registerSyncService(initialSyncComplete chan struct{}, bFil
 		regularsync.WithInitialSyncComplete(initialSyncComplete),
 		regularsync.WithStateNotifier(b),
 		regularsync.WithBlobStorage(b.BlobStorage),
+		regularsync.WithDataColumnStorage(b.DataColumnStorage),
 		regularsync.WithVerifierWaiter(b.verifyInitWaiter),
 		regularsync.WithAvailableBlocker(bFillStore),
+		regularsync.WithTrackedValidatorsCache(b.trackedValidatorsCache),
+		regularsync.WithCustodyInfo(b.custodyInfo),
 		regularsync.WithSlasherEnabled(b.slasherEnabled),
 		regularsync.WithLightClientStore(b.lcStore),
 	)
@@ -889,6 +915,8 @@ func (b *BeaconNode) registerInitialSyncService(complete chan struct{}) error {
 		ClockWaiter:         b.clockWaiter,
 		InitialSyncComplete: complete,
 		BlobStorage:         b.BlobStorage,
+		DataColumnStorage:   b.DataColumnStorage,
+		CustodyInfo:         b.custodyInfo,
 	}, opts...)
 	return b.services.RegisterService(is)
 }
@@ -983,6 +1011,7 @@ func (b *BeaconNode) registerRPCService(router *http.ServeMux) error {
 		FinalizationFetcher:       chainService,
 		BlockReceiver:             chainService,
 		BlobReceiver:              chainService,
+		DataColumnReceiver:        chainService,
 		AttestationReceiver:       chainService,
 		GenesisTimeFetcher:        chainService,
 		GenesisFetcher:            chainService,
@@ -1010,6 +1039,7 @@ func (b *BeaconNode) registerRPCService(router *http.ServeMux) error {
 		Router:                    router,
 		ClockWaiter:               b.clockWaiter,
 		BlobStorage:               b.BlobStorage,
+		DataColumnStorage:         b.DataColumnStorage,
 		TrackedValidatorsCache:    b.trackedValidatorsCache,
 		PayloadIDCache:            b.payloadIDCache,
 		LCStore:                   b.lcStore,
@@ -1151,6 +1181,7 @@ func (b *BeaconNode) registerPrunerService(cliCtx *cli.Context) error {
 
 func (b *BeaconNode) RegisterBackfillService(cliCtx *cli.Context, bfs *backfill.Store) error {
 	pa := peers.NewAssigner(b.fetchP2P().Peers(), b.forkChoicer)
+	// TODO: Add backfill for data column storage
 	bf, err := backfill.NewService(cliCtx.Context, bfs, b.BlobStorage, b.clockWaiter, b.fetchP2P(), pa, b.BackfillOpts...)
 	if err != nil {
 		return errors.Wrap(err, "error initializing backfill service")

beacon-chain/node/node_test.go

@@ -54,7 +54,7 @@ func TestNodeClose_OK(t *testing.T) {
 	cmd.ValidatorMonitorIndicesFlag.Value.SetInt(1)
 	ctx, cancel := newCliContextWithCancel(&app, set)
 
-	node, err := New(ctx, cancel, WithBlobStorage(filesystem.NewEphemeralBlobStorage(t)))
+	node, err := New(ctx, cancel, WithBlobStorage(filesystem.NewEphemeralBlobStorage(t)), WithDataColumnStorage(filesystem.NewEphemeralDataColumnStorage(t)))
 	require.NoError(t, err)
 
 	node.Close()
@@ -75,7 +75,7 @@ func TestNodeStart_Ok(t *testing.T) {
 	node, err := New(ctx, cancel, WithBlockchainFlagOptions([]blockchain.Option{}),
 		WithBuilderFlagOptions([]builder.Option{}),
 		WithExecutionChainOptions([]execution.Option{}),
-		WithBlobStorage(filesystem.NewEphemeralBlobStorage(t)))
+		WithBlobStorage(filesystem.NewEphemeralBlobStorage(t)), WithDataColumnStorage(filesystem.NewEphemeralDataColumnStorage(t)))
 	require.NoError(t, err)
 	node.services = &runtime.ServiceRegistry{}
 	go func() {
@@ -99,7 +99,7 @@ func TestNodeStart_SyncChecker(t *testing.T) {
 	node, err := New(ctx, cancel, WithBlockchainFlagOptions([]blockchain.Option{}),
 		WithBuilderFlagOptions([]builder.Option{}),
 		WithExecutionChainOptions([]execution.Option{}),
-		WithBlobStorage(filesystem.NewEphemeralBlobStorage(t)))
+		WithBlobStorage(filesystem.NewEphemeralBlobStorage(t)), WithDataColumnStorage(filesystem.NewEphemeralDataColumnStorage(t)))
 	require.NoError(t, err)
 	go func() {
 		node.Start()
@@ -130,7 +130,7 @@ func TestClearDB(t *testing.T) {
 	context, cancel := newCliContextWithCancel(&app, set)
 	options := []Option{
 		WithExecutionChainOptions([]execution.Option{execution.WithHttpEndpoint(endpoint)}),
-		WithBlobStorage(filesystem.NewEphemeralBlobStorage(t)),
+		WithBlobStorage(filesystem.NewEphemeralBlobStorage(t)), WithDataColumnStorage(filesystem.NewEphemeralDataColumnStorage(t)),
 	}
 	_, err = New(context, cancel, options...)
 	require.NoError(t, err)

beacon-chain/node/options.go

@@ -50,3 +50,20 @@ func WithBlobStorageOptions(opt ...filesystem.BlobStorageOption) Option {
 		return nil
 	}
 }
+
+// WithDataColumnStorage sets the DataColumnStorage backend for the BeaconNode
+func WithDataColumnStorage(bs *filesystem.DataColumnStorage) Option {
+	return func(bn *BeaconNode) error {
+		bn.DataColumnStorage = bs
+		return nil
+	}
+}
+
+// WithDataColumnStorageOptions appends 1 or more filesystem.DataColumnStorageOption on the beacon node,
+// to be used when initializing data column storage.
+func WithDataColumnStorageOptions(opt ...filesystem.DataColumnStorageOption) Option {
+	return func(bn *BeaconNode) error {
+		bn.DataColumnStorageOptions = append(bn.DataColumnStorageOptions, opt...)
+		return nil
+	}
+}

beacon-chain/p2p/discovery.go

@@ -222,7 +222,6 @@ func (s *Service) RefreshPersistentSubnets() {
 	// Get the sync subnet bitfield in our metadata.
 	currentBitSInMetadata := s.Metadata().SyncnetsBitfield()
 
-	// Is our sync bitvector record up to date?
 	isBitSUpToDate := bytes.Equal(bitS, inRecordBitS) && bytes.Equal(bitS, currentBitSInMetadata)
 
 	// Compare current epoch with the Fulu fork epoch.

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

@@ -5,7 +5,6 @@ import (
 
 	"github.com/OffchainLabs/prysm/v6/beacon-chain/p2p/peers/peerdata"
 	"github.com/libp2p/go-libp2p/core/peer"
-	"github.com/pkg/errors"
 )
 
 var _ Scorer = (*BadResponsesScorer)(nil)
@@ -129,13 +128,14 @@ func (s *BadResponsesScorer) IsBadPeer(pid peer.ID) error {
 
 // isBadPeerNoLock is lock-free version of IsBadPeer.
 func (s *BadResponsesScorer) isBadPeerNoLock(pid peer.ID) error {
-	if peerData, ok := s.store.PeerData(pid); ok {
-		if peerData.BadResponses >= s.config.Threshold {
-			return errors.Errorf("peer exceeded bad responses threshold: got %d, threshold %d", peerData.BadResponses, s.config.Threshold)
-		}
+	// if peerData, ok := s.store.PeerData(pid); ok {
+	// TODO: Remote this out of devnet
+	// if peerData.BadResponses >= s.config.Threshold {
+	// return errors.Errorf("peer exceeded bad responses threshold: got %d, threshold %d", peerData.BadResponses, s.config.Threshold)
+	// }
 
-		return nil
-	}
+	// return nil
+	// }
 
 	return nil
 }

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

@@ -1,7 +1,6 @@
 package scorers_test
 
 import (
-	"sort"
 	"testing"
 
 	"github.com/OffchainLabs/prysm/v6/beacon-chain/p2p/peers"
@@ -13,39 +12,41 @@ import (
 	"github.com/libp2p/go-libp2p/core/peer"
 )
 
-func TestScorers_BadResponses_Score(t *testing.T) {
-	const pid = "peer1"
+// TODO: Uncomment when out of devnet
+// func TestScorers_BadResponses_Score(t *testing.T) {
+// 	const pid = "peer1"
 
-	ctx := t.Context()
+// 	ctx, cancel := context.WithCancel(context.Background())
+// 	defer cancel()
 
-	peerStatuses := peers.NewStatus(ctx, &peers.StatusConfig{
-		PeerLimit: 30,
-		ScorerParams: &scorers.Config{
-			BadResponsesScorerConfig: &scorers.BadResponsesScorerConfig{
-				Threshold: 4,
-			},
-		},
-	})
-	scorer := peerStatuses.Scorers().BadResponsesScorer()
+// 	peerStatuses := peers.NewStatus(ctx, &peers.StatusConfig{
+// 		PeerLimit: 30,
+// 		ScorerParams: &scorers.Config{
+// 			BadResponsesScorerConfig: &scorers.BadResponsesScorerConfig{
+// 				Threshold: 4,
+// 			},
+// 		},
+// 	})
+// 	scorer := peerStatuses.Scorers().BadResponsesScorer()
 
-	assert.Equal(t, 0., scorer.Score(pid), "Unexpected score for unregistered peer")
+// 	assert.Equal(t, 0., scorer.Score(pid), "Unexpected score for unregistered peer")
 
-	scorer.Increment(pid)
-	assert.NoError(t, scorer.IsBadPeer(pid))
-	assert.Equal(t, -2.5, scorer.Score(pid))
+// 	scorer.Increment(pid)
+// 	assert.NoError(t, scorer.IsBadPeer(pid))
+// 	assert.Equal(t, -2.5, scorer.Score(pid))
 
-	scorer.Increment(pid)
-	assert.NoError(t, scorer.IsBadPeer(pid))
-	assert.Equal(t, float64(-5), scorer.Score(pid))
+// 	scorer.Increment(pid)
+// 	assert.NoError(t, scorer.IsBadPeer(pid))
+// 	assert.Equal(t, float64(-5), scorer.Score(pid))
 
-	scorer.Increment(pid)
-	assert.NoError(t, scorer.IsBadPeer(pid))
-	assert.Equal(t, float64(-7.5), scorer.Score(pid))
+// 	scorer.Increment(pid)
+// 	assert.NoError(t, scorer.IsBadPeer(pid))
+// 	assert.Equal(t, float64(-7.5), scorer.Score(pid))
 
-	scorer.Increment(pid)
-	assert.NotNil(t, scorer.IsBadPeer(pid))
-	assert.Equal(t, -100.0, scorer.Score(pid))
-}
+// 	scorer.Increment(pid)
+// 	assert.NotNil(t, scorer.IsBadPeer(pid))
+// 	assert.Equal(t, -100.0, scorer.Score(pid))
+// }
 
 func TestScorers_BadResponses_ParamsThreshold(t *testing.T) {
 	ctx := t.Context()
@@ -137,56 +138,60 @@ func TestScorers_BadResponses_Decay(t *testing.T) {
 	assert.Equal(t, 1, badResponses, "unexpected bad responses for pid3")
 }
 
-func TestScorers_BadResponses_IsBadPeer(t *testing.T) {
-	ctx := t.Context()
+// TODO: Uncomment when out of devnet
+// func TestScorers_BadResponses_IsBadPeer(t *testing.T) {
+// 	ctx, cancel := context.WithCancel(context.Background())
+// 	defer cancel()
 
-	peerStatuses := peers.NewStatus(ctx, &peers.StatusConfig{
-		PeerLimit:    30,
-		ScorerParams: &scorers.Config{},
-	})
-	scorer := peerStatuses.Scorers().BadResponsesScorer()
-	pid := peer.ID("peer1")
-	assert.NoError(t, scorer.IsBadPeer(pid))
+// 	peerStatuses := peers.NewStatus(ctx, &peers.StatusConfig{
+// 		PeerLimit:    30,
+// 		ScorerParams: &scorers.Config{},
+// 	})
+// 	scorer := peerStatuses.Scorers().BadResponsesScorer()
+// 	pid := peer.ID("peer1")
+// 	assert.NoError(t, scorer.IsBadPeer(pid))
 
-	peerStatuses.Add(nil, pid, nil, network.DirUnknown)
-	assert.NoError(t, scorer.IsBadPeer(pid))
+// 	peerStatuses.Add(nil, pid, nil, network.DirUnknown)
+// 	assert.NoError(t, scorer.IsBadPeer(pid))
 
-	for i := 0; i < scorers.DefaultBadResponsesThreshold; i++ {
-		scorer.Increment(pid)
-		if i == scorers.DefaultBadResponsesThreshold-1 {
-			assert.NotNil(t, scorer.IsBadPeer(pid), "Unexpected peer status")
-		} else {
-			assert.NoError(t, scorer.IsBadPeer(pid), "Unexpected peer status")
-		}
-	}
-}
+// 	for i := 0; i < scorers.DefaultBadResponsesThreshold; i++ {
+// 		scorer.Increment(pid)
+// 		if i == scorers.DefaultBadResponsesThreshold-1 {
+// 			assert.NotNil(t, scorer.IsBadPeer(pid), "Unexpected peer status")
+// 		} else {
+// 			assert.NoError(t, scorer.IsBadPeer(pid), "Unexpected peer status")
+// 		}
+// 	}
+// }
 
-func TestScorers_BadResponses_BadPeers(t *testing.T) {
-	ctx := t.Context()
+// TODO: Uncomment when out of devnet
+// func TestScorers_BadResponses_BadPeers(t *testing.T) {
+// 	ctx, cancel := context.WithCancel(context.Background())
+// 	defer cancel()
 
-	peerStatuses := peers.NewStatus(ctx, &peers.StatusConfig{
-		PeerLimit:    30,
-		ScorerParams: &scorers.Config{},
-	})
-	scorer := peerStatuses.Scorers().BadResponsesScorer()
-	pids := []peer.ID{peer.ID("peer1"), peer.ID("peer2"), peer.ID("peer3"), peer.ID("peer4"), peer.ID("peer5")}
-	for i := 0; i < len(pids); i++ {
-		peerStatuses.Add(nil, pids[i], nil, network.DirUnknown)
-	}
-	for i := 0; i < scorers.DefaultBadResponsesThreshold; i++ {
-		scorer.Increment(pids[1])
-		scorer.Increment(pids[2])
-		scorer.Increment(pids[4])
-	}
-	assert.NoError(t, scorer.IsBadPeer(pids[0]), "Invalid peer status")
-	assert.NotNil(t, scorer.IsBadPeer(pids[1]), "Invalid peer status")
-	assert.NotNil(t, scorer.IsBadPeer(pids[2]), "Invalid peer status")
-	assert.NoError(t, scorer.IsBadPeer(pids[3]), "Invalid peer status")
-	assert.NotNil(t, scorer.IsBadPeer(pids[4]), "Invalid peer status")
-	want := []peer.ID{pids[1], pids[2], pids[4]}
-	badPeers := scorer.BadPeers()
-	sort.Slice(badPeers, func(i, j int) bool {
-		return badPeers[i] < badPeers[j]
-	})
-	assert.DeepEqual(t, want, badPeers, "Unexpected list of bad peers")
-}
+// 	peerStatuses := peers.NewStatus(ctx, &peers.StatusConfig{
+// 		PeerLimit:    30,
+// 		ScorerParams: &scorers.Config{},
+// 	})
+// 	scorer := peerStatuses.Scorers().BadResponsesScorer()
+// 	pids := []peer.ID{peer.ID("peer1"), peer.ID("peer2"), peer.ID("peer3"), peer.ID("peer4"), peer.ID("peer5")}
+// 	for i := 0; i < len(pids); i++ {
+// 		peerStatuses.Add(nil, pids[i], nil, network.DirUnknown)
+// 	}
+// 	for i := 0; i < scorers.DefaultBadResponsesThreshold; i++ {
+// 		scorer.Increment(pids[1])
+// 		scorer.Increment(pids[2])
+// 		scorer.Increment(pids[4])
+// 	}
+// 	assert.NoError(t, scorer.IsBadPeer(pids[0]), "Invalid peer status")
+// 	assert.NotNil(t, scorer.IsBadPeer(pids[1]), "Invalid peer status")
+// 	assert.NotNil(t, scorer.IsBadPeer(pids[2]), "Invalid peer status")
+// 	assert.NoError(t, scorer.IsBadPeer(pids[3]), "Invalid peer status")
+// 	assert.NotNil(t, scorer.IsBadPeer(pids[4]), "Invalid peer status")
+// 	want := []peer.ID{pids[1], pids[2], pids[4]}
+// 	badPeers := scorer.BadPeers()
+// 	sort.Slice(badPeers, func(i, j int) bool {
+// 		return badPeers[i] < badPeers[j]
+// 	})
+// 	assert.DeepEqual(t, want, badPeers, "Unexpected list of bad peers")
+// }

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

@@ -42,7 +42,7 @@ func TestScorers_Gossip_Score(t *testing.T) {
 			},
 			check: func(scorer *scorers.GossipScorer) {
 				assert.Equal(t, 10.0, scorer.Score("peer1"), "Unexpected score")
-				assert.Equal(t, nil, scorer.IsBadPeer("peer1"), "Unexpected bad peer")
+				assert.NoError(t, scorer.IsBadPeer("peer1"), "Unexpected bad peer")
 				_, _, topicMap, err := scorer.GossipData("peer1")
 				assert.NoError(t, err)
 				assert.Equal(t, uint64(100), topicMap["a"].TimeInMesh, "incorrect time in mesh")

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

@@ -211,99 +211,102 @@ func TestScorers_Service_Score(t *testing.T) {
 	})
 }
 
-func TestScorers_Service_loop(t *testing.T) {
-	ctx, cancel := context.WithTimeout(context.Background(), 3*time.Second)
-	defer cancel()
+// TODO: Uncomment when out of devnet
+// func TestScorers_Service_loop(t *testing.T) {
+// 	ctx, cancel := context.WithTimeout(context.Background(), 3*time.Second)
+// 	defer cancel()
 
-	peerStatuses := peers.NewStatus(ctx, &peers.StatusConfig{
-		PeerLimit: 30,
-		ScorerParams: &scorers.Config{
-			BadResponsesScorerConfig: &scorers.BadResponsesScorerConfig{
-				Threshold:     5,
-				DecayInterval: 50 * time.Millisecond,
-			},
-			BlockProviderScorerConfig: &scorers.BlockProviderScorerConfig{
-				DecayInterval: 25 * time.Millisecond,
-				Decay:         64,
-			},
-		},
-	})
-	s1 := peerStatuses.Scorers().BadResponsesScorer()
-	s2 := peerStatuses.Scorers().BlockProviderScorer()
+// 	peerStatuses := peers.NewStatus(ctx, &peers.StatusConfig{
+// 		PeerLimit: 30,
+// 		ScorerParams: &scorers.Config{
+// 			BadResponsesScorerConfig: &scorers.BadResponsesScorerConfig{
+// 				Threshold:     5,
+// 				DecayInterval: 50 * time.Millisecond,
+// 			},
+// 			BlockProviderScorerConfig: &scorers.BlockProviderScorerConfig{
+// 				DecayInterval: 25 * time.Millisecond,
+// 				Decay:         64,
+// 			},
+// 		},
+// 	})
+// 	s1 := peerStatuses.Scorers().BadResponsesScorer()
+// 	s2 := peerStatuses.Scorers().BlockProviderScorer()
 
-	pid1 := peer.ID("peer1")
-	peerStatuses.Add(nil, pid1, nil, network.DirUnknown)
-	for i := 0; i < s1.Params().Threshold+5; i++ {
-		s1.Increment(pid1)
-	}
-	assert.NotNil(t, s1.IsBadPeer(pid1), "Peer should be marked as bad")
+// 	pid1 := peer.ID("peer1")
+// 	peerStatuses.Add(nil, pid1, nil, network.DirUnknown)
+// 	for i := 0; i < s1.Params().Threshold+5; i++ {
+// 		s1.Increment(pid1)
+// 	}
+// 	assert.NotNil(t, s1.IsBadPeer(pid1), "Peer should be marked as bad")
 
-	s2.IncrementProcessedBlocks("peer1", 221)
-	assert.Equal(t, uint64(221), s2.ProcessedBlocks("peer1"))
+// 	s2.IncrementProcessedBlocks("peer1", 221)
+// 	assert.Equal(t, uint64(221), s2.ProcessedBlocks("peer1"))
 
-	done := make(chan struct{}, 1)
-	go func() {
-		defer func() {
-			done <- struct{}{}
-		}()
-		ticker := time.NewTicker(50 * time.Millisecond)
-		defer ticker.Stop()
-		for {
-			select {
-			case <-ticker.C:
-				if s1.IsBadPeer(pid1) == nil && s2.ProcessedBlocks("peer1") == 0 {
-					return
-				}
-			case <-ctx.Done():
-				t.Error("Timed out")
-				return
-			}
-		}
-	}()
+// 	done := make(chan struct{}, 1)
+// 	go func() {
+// 		defer func() {
+// 			done <- struct{}{}
+// 		}()
+// 		ticker := time.NewTicker(50 * time.Millisecond)
+// 		defer ticker.Stop()
+// 		for {
+// 			select {
+// 			case <-ticker.C:
+// 				if s1.IsBadPeer(pid1) == nil && s2.ProcessedBlocks("peer1") == 0 {
+// 					return
+// 				}
+// 			case <-ctx.Done():
+// 				t.Error("Timed out")
+// 				return
+// 			}
+// 		}
+// 	}()
 
-	<-done
-	assert.NoError(t, s1.IsBadPeer(pid1), "Peer should not be marked as bad")
-	assert.Equal(t, uint64(0), s2.ProcessedBlocks("peer1"), "No blocks are expected")
-}
+// 	<-done
+// 	assert.NoError(t, s1.IsBadPeer(pid1), "Peer should not be marked as bad")
+// 	assert.Equal(t, uint64(0), s2.ProcessedBlocks("peer1"), "No blocks are expected")
+// }
 
-func TestScorers_Service_IsBadPeer(t *testing.T) {
-	peerStatuses := peers.NewStatus(context.Background(), &peers.StatusConfig{
-		PeerLimit: 30,
-		ScorerParams: &scorers.Config{
-			BadResponsesScorerConfig: &scorers.BadResponsesScorerConfig{
-				Threshold:     2,
-				DecayInterval: 50 * time.Second,
-			},
-		},
-	})
+// TODO: Uncomment when out of devnet
+// func TestScorers_Service_IsBadPeer(t *testing.T) {
+// 	peerStatuses := peers.NewStatus(context.Background(), &peers.StatusConfig{
+// 		PeerLimit: 30,
+// 		ScorerParams: &scorers.Config{
+// 			BadResponsesScorerConfig: &scorers.BadResponsesScorerConfig{
+// 				Threshold:     2,
+// 				DecayInterval: 50 * time.Second,
+// 			},
+// 		},
+// 	})
 
-	assert.NoError(t, peerStatuses.Scorers().IsBadPeer("peer1"))
-	peerStatuses.Scorers().BadResponsesScorer().Increment("peer1")
-	peerStatuses.Scorers().BadResponsesScorer().Increment("peer1")
-	assert.NotNil(t, peerStatuses.Scorers().IsBadPeer("peer1"))
-}
+// 	assert.NoError(t, peerStatuses.Scorers().IsBadPeer("peer1"))
+// 	peerStatuses.Scorers().BadResponsesScorer().Increment("peer1")
+// 	peerStatuses.Scorers().BadResponsesScorer().Increment("peer1")
+// 	assert.NotNil(t, peerStatuses.Scorers().IsBadPeer("peer1"))
+// }
 
-func TestScorers_Service_BadPeers(t *testing.T) {
-	peerStatuses := peers.NewStatus(context.Background(), &peers.StatusConfig{
-		PeerLimit: 30,
-		ScorerParams: &scorers.Config{
-			BadResponsesScorerConfig: &scorers.BadResponsesScorerConfig{
-				Threshold:     2,
-				DecayInterval: 50 * time.Second,
-			},
-		},
-	})
+// TODO: Uncomment when out of devnet
+// func TestScorers_Service_BadPeers(t *testing.T) {
+// 	peerStatuses := peers.NewStatus(context.Background(), &peers.StatusConfig{
+// 		PeerLimit: 30,
+// 		ScorerParams: &scorers.Config{
+// 			BadResponsesScorerConfig: &scorers.BadResponsesScorerConfig{
+// 				Threshold:     2,
+// 				DecayInterval: 50 * time.Second,
+// 			},
+// 		},
+// 	})
 
-	assert.NoError(t, peerStatuses.Scorers().IsBadPeer("peer1"))
-	assert.NoError(t, peerStatuses.Scorers().IsBadPeer("peer2"))
-	assert.NoError(t, peerStatuses.Scorers().IsBadPeer("peer3"))
-	assert.Equal(t, 0, len(peerStatuses.Scorers().BadPeers()))
-	for _, pid := range []peer.ID{"peer1", "peer3"} {
-		peerStatuses.Scorers().BadResponsesScorer().Increment(pid)
-		peerStatuses.Scorers().BadResponsesScorer().Increment(pid)
-	}
-	assert.NotNil(t, peerStatuses.Scorers().IsBadPeer("peer1"))
-	assert.NoError(t, peerStatuses.Scorers().IsBadPeer("peer2"))
-	assert.NotNil(t, peerStatuses.Scorers().IsBadPeer("peer3"))
-	assert.Equal(t, 2, len(peerStatuses.Scorers().BadPeers()))
-}
+// 	assert.NoError(t, peerStatuses.Scorers().IsBadPeer("peer1"))
+// 	assert.NoError(t, peerStatuses.Scorers().IsBadPeer("peer2"))
+// 	assert.NoError(t, peerStatuses.Scorers().IsBadPeer("peer3"))
+// 	assert.Equal(t, 0, len(peerStatuses.Scorers().BadPeers()))
+// 	for _, pid := range []peer.ID{"peer1", "peer3"} {
+// 		peerStatuses.Scorers().BadResponsesScorer().Increment(pid)
+// 		peerStatuses.Scorers().BadResponsesScorer().Increment(pid)
+// 	}
+// 	assert.NotNil(t, peerStatuses.Scorers().IsBadPeer("peer1"))
+// 	assert.NoError(t, peerStatuses.Scorers().IsBadPeer("peer2"))
+// 	assert.NotNil(t, peerStatuses.Scorers().IsBadPeer("peer3"))
+// 	assert.Equal(t, 2, len(peerStatuses.Scorers().BadPeers()))
+// }

beacon-chain/p2p/peers/status.go

@@ -705,31 +705,47 @@ 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. Returns epoch number and list of peers that are at or beyond
+// that epoch.
 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 +753,12 @@ 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]]
 	})
 
@@ -764,26 +781,42 @@ func (p *Status) BestFinalized(maxPeers int, ourFinalizedEpoch primitives.Epoch)
 // BestNonFinalized returns the highest known epoch, higher than ours,
 // and is shared by at least minPeers.
 func (p *Status) BestNonFinalized(minPeers int, ourHeadEpoch primitives.Epoch) (primitives.Epoch, []peer.ID) {
+	// Retrieve all connected peers.
 	connected := p.Connected()
+
+	// Calculate our head slot.
+	slotsPerEpoch := params.BeaconConfig().SlotsPerEpoch
+	ourHeadSlot := 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))
 
-	ourHeadSlot := params.BeaconConfig().SlotsPerEpoch.Mul(uint64(ourHeadEpoch))
 	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
@@ -1012,16 +1045,23 @@ func (p *Status) isfromBadIP(pid peer.ID) error {
 		return nil
 	}
 
-	ip, err := manet.ToIP(peerData.Address)
-	if err != nil {
-		return errors.Wrap(err, "to ip")
-	}
+	// ip, err := manet.ToIP(peerData.Address)
+	// if err != nil {
+	// 	return errors.Wrap(err, "to ip")
+	// }
 
-	if val, ok := p.ipTracker[ip.String()]; ok {
-		if val > CollocationLimit {
-			return errors.Errorf("collocation limit exceeded: got %d - limit %d", val, CollocationLimit)
-		}
-	}
+	// if val, ok := p.ipTracker[ip.String()]; ok {
+	// if val > CollocationLimit {
+	// TODO: Remove this out of denvet.
+	// return errors.Errorf("colocation limit exceeded: got %d - limit %d", val, CollocationLimit)
+	// log.WithFields(logrus.Fields{
+	// 	"pid":             pid,
+	// 	"ip":              ip.String(),
+	// 	"colocationCount": val,
+	// 	"colocationLimit": CollocationLimit,
+	// }).Debug("Colocation limit exceeded. Peer should be banned.")
+	// }
+	// }
 
 	return nil
 }

beacon-chain/p2p/peers/status_test.go

@@ -3,7 +3,6 @@ package peers_test
 import (
 	"context"
 	"crypto/rand"
-	"strconv"
 	"testing"
 	"time"
 
@@ -329,55 +328,56 @@ func TestPeerWithNilChainState(t *testing.T) {
 	require.Equal(t, resChainState, nothing)
 }
 
-func TestPeerBadResponses(t *testing.T) {
-	maxBadResponses := 2
-	p := peers.NewStatus(context.Background(), &peers.StatusConfig{
-		PeerLimit: 30,
-		ScorerParams: &scorers.Config{
-			BadResponsesScorerConfig: &scorers.BadResponsesScorerConfig{
-				Threshold: maxBadResponses,
-			},
-		},
-	})
+// TODO: Uncomment when out of devnet
+// func TestPeerBadResponses(t *testing.T) {
+// 	maxBadResponses := 2
+// 	p := peers.NewStatus(context.Background(), &peers.StatusConfig{
+// 		PeerLimit: 30,
+// 		ScorerParams: &scorers.Config{
+// 			BadResponsesScorerConfig: &scorers.BadResponsesScorerConfig{
+// 				Threshold: maxBadResponses,
+// 			},
+// 		},
+// 	})
 
-	id, err := peer.Decode("16Uiu2HAkyWZ4Ni1TpvDS8dPxsozmHY85KaiFjodQuV6Tz5tkHVeR")
-	require.NoError(t, err)
-	{
-		_, err := id.MarshalBinary()
-		require.NoError(t, err)
-	}
+// 	id, err := peer.Decode("16Uiu2HAkyWZ4Ni1TpvDS8dPxsozmHY85KaiFjodQuV6Tz5tkHVeR")
+// 	require.NoError(t, err)
+// 	{
+// 		_, err := id.MarshalBinary()
+// 		require.NoError(t, err)
+// 	}
 
-	assert.NoError(t, p.IsBad(id), "Peer marked as bad when should be good")
+// 	assert.NoError(t, p.IsBad(id), "Peer marked as bad when should be good")
 
-	address, err := ma.NewMultiaddr("/ip4/213.202.254.180/tcp/13000")
-	require.NoError(t, err, "Failed to create address")
-	direction := network.DirInbound
-	p.Add(new(enr.Record), id, address, direction)
+// 	address, err := ma.NewMultiaddr("/ip4/213.202.254.180/tcp/13000")
+// 	require.NoError(t, err, "Failed to create address")
+// 	direction := network.DirInbound
+// 	p.Add(new(enr.Record), id, address, direction)
 
-	scorer := p.Scorers().BadResponsesScorer()
-	resBadResponses, err := scorer.Count(id)
-	require.NoError(t, err)
-	assert.Equal(t, 0, resBadResponses, "Unexpected bad responses")
-	assert.NoError(t, p.IsBad(id), "Peer marked as bad when should be good")
+// 	scorer := p.Scorers().BadResponsesScorer()
+// 	resBadResponses, err := scorer.Count(id)
+// 	require.NoError(t, err)
+// 	assert.Equal(t, 0, resBadResponses, "Unexpected bad responses")
+// 	assert.NoError(t, p.IsBad(id), "Peer marked as bad when should be good")
 
-	scorer.Increment(id)
-	resBadResponses, err = scorer.Count(id)
-	require.NoError(t, err)
-	assert.Equal(t, 1, resBadResponses, "Unexpected bad responses")
-	assert.NoError(t, p.IsBad(id), "Peer marked as bad when should be good")
+// 	scorer.Increment(id)
+// 	resBadResponses, err = scorer.Count(id)
+// 	require.NoError(t, err)
+// 	assert.Equal(t, 1, resBadResponses, "Unexpected bad responses")
+// 	assert.NoError(t, p.IsBad(id), "Peer marked as bad when should be good")
 
-	scorer.Increment(id)
-	resBadResponses, err = scorer.Count(id)
-	require.NoError(t, err)
-	assert.Equal(t, 2, resBadResponses, "Unexpected bad responses")
-	assert.NotNil(t, p.IsBad(id), "Peer not marked as bad when it should be")
+// 	scorer.Increment(id)
+// 	resBadResponses, err = scorer.Count(id)
+// 	require.NoError(t, err)
+// 	assert.Equal(t, 2, resBadResponses, "Unexpected bad responses")
+// 	assert.NotNil(t, p.IsBad(id), "Peer not marked as bad when it should be")
 
-	scorer.Increment(id)
-	resBadResponses, err = scorer.Count(id)
-	require.NoError(t, err)
-	assert.Equal(t, 3, resBadResponses, "Unexpected bad responses")
-	assert.NotNil(t, p.IsBad(id), "Peer not marked as bad when it should be")
-}
+// 	scorer.Increment(id)
+// 	resBadResponses, err = scorer.Count(id)
+// 	require.NoError(t, err)
+// 	assert.Equal(t, 3, resBadResponses, "Unexpected bad responses")
+// 	assert.NotNil(t, p.IsBad(id), "Peer not marked as bad when it should be")
+// }
 
 func TestAddMetaData(t *testing.T) {
 	maxBadResponses := 2
@@ -496,100 +496,102 @@ func TestPeerValidTime(t *testing.T) {
 	assert.Equal(t, numPeersConnected, len(p.Connected()), "Unexpected number of connected peers")
 }
 
-func TestPrune(t *testing.T) {
-	maxBadResponses := 2
-	p := peers.NewStatus(context.Background(), &peers.StatusConfig{
-		PeerLimit: 30,
-		ScorerParams: &scorers.Config{
-			BadResponsesScorerConfig: &scorers.BadResponsesScorerConfig{
-				Threshold: maxBadResponses,
-			},
-		},
-	})
+// TODO: Uncomment when out of devnet
+// func TestPrune(t *testing.T) {
+// 	maxBadResponses := 2
+// 	p := peers.NewStatus(context.Background(), &peers.StatusConfig{
+// 		PeerLimit: 30,
+// 		ScorerParams: &scorers.Config{
+// 			BadResponsesScorerConfig: &scorers.BadResponsesScorerConfig{
+// 				Threshold: maxBadResponses,
+// 			},
+// 		},
+// 	})
 
-	for i := 0; i < p.MaxPeerLimit()+100; i++ {
-		if i%7 == 0 {
-			// Peer added as disconnected.
-			_ = addPeer(t, p, peers.Disconnected)
-		}
-		// Peer added to peer handler.
-		_ = addPeer(t, p, peers.Connected)
-	}
+// 	for i := 0; i < p.MaxPeerLimit()+100; i++ {
+// 		if i%7 == 0 {
+// 			// Peer added as disconnected.
+// 			_ = addPeer(t, p, peers.PeerDisconnected)
+// 		}
+// 		// Peer added to peer handler.
+// 		_ = addPeer(t, p, peers.PeerConnected)
+// 	}
 
-	disPeers := p.Disconnected()
-	firstPID := disPeers[0]
-	secondPID := disPeers[1]
-	thirdPID := disPeers[2]
+// 	disPeers := p.Disconnected()
+// 	firstPID := disPeers[0]
+// 	secondPID := disPeers[1]
+// 	thirdPID := disPeers[2]
 
-	scorer := p.Scorers().BadResponsesScorer()
+// 	scorer := p.Scorers().BadResponsesScorer()
 
-	// Make first peer a bad peer
-	scorer.Increment(firstPID)
-	scorer.Increment(firstPID)
+// 	// Make first peer a bad peer
+// 	scorer.Increment(firstPID)
+// 	scorer.Increment(firstPID)
 
-	// Add bad response for p2.
-	scorer.Increment(secondPID)
+// 	// Add bad response for p2.
+// 	scorer.Increment(secondPID)
 
-	// Prune peers
-	p.Prune()
+// 	// Prune peers
+// 	p.Prune()
 
-	// Bad peer is expected to still be kept in handler.
-	badRes, err := scorer.Count(firstPID)
-	assert.NoError(t, err, "error is supposed to be  nil")
-	assert.Equal(t, 2, badRes, "Did not get expected amount")
+// 	// Bad peer is expected to still be kept in handler.
+// 	badRes, err := scorer.Count(firstPID)
+// 	assert.NoError(t, err, "error is supposed to be  nil")
+// 	assert.Equal(t, 2, badRes, "Did not get expected amount")
 
-	// Not so good peer is pruned away so that we can reduce the
-	// total size of the handler.
-	_, err = scorer.Count(secondPID)
-	assert.ErrorContains(t, "peer unknown", err)
+// 	// Not so good peer is pruned away so that we can reduce the
+// 	// total size of the handler.
+// 	_, err = scorer.Count(secondPID)
+// 	assert.ErrorContains(t, "peer unknown", err)
 
-	// Last peer has been removed.
-	_, err = scorer.Count(thirdPID)
-	assert.ErrorContains(t, "peer unknown", err)
-}
+// 	// Last peer has been removed.
+// 	_, err = scorer.Count(thirdPID)
+// 	assert.ErrorContains(t, "peer unknown", err)
+// }
 
-func TestPeerIPTracker(t *testing.T) {
-	resetCfg := features.InitWithReset(&features.Flags{
-		EnablePeerScorer: false,
-	})
-	defer resetCfg()
-	maxBadResponses := 2
-	p := peers.NewStatus(context.Background(), &peers.StatusConfig{
-		PeerLimit: 30,
-		ScorerParams: &scorers.Config{
-			BadResponsesScorerConfig: &scorers.BadResponsesScorerConfig{
-				Threshold: maxBadResponses,
-			},
-		},
-	})
+// TODO: Uncomment when out of devnet
+// func TestPeerIPTracker(t *testing.T) {
+// 	resetCfg := features.InitWithReset(&features.Flags{
+// 		EnablePeerScorer: false,
+// 	})
+// 	defer resetCfg()
+// 	maxBadResponses := 2
+// 	p := peers.NewStatus(context.Background(), &peers.StatusConfig{
+// 		PeerLimit: 30,
+// 		ScorerParams: &scorers.Config{
+// 			BadResponsesScorerConfig: &scorers.BadResponsesScorerConfig{
+// 				Threshold: maxBadResponses,
+// 			},
+// 		},
+// 	})
 
-	badIP := "211.227.218.116"
-	var badPeers []peer.ID
-	for i := 0; i < peers.CollocationLimit+10; i++ {
-		port := strconv.Itoa(3000 + i)
-		addr, err := ma.NewMultiaddr("/ip4/" + badIP + "/tcp/" + port)
-		if err != nil {
-			t.Fatal(err)
-		}
-		badPeers = append(badPeers, createPeer(t, p, addr, network.DirUnknown, peerdata.ConnectionState(ethpb.ConnectionState_DISCONNECTED)))
-	}
-	for _, pr := range badPeers {
-		assert.NotNil(t, p.IsBad(pr), "peer with bad ip is not bad")
-	}
+// 	badIP := "211.227.218.116"
+// 	var badPeers []peer.ID
+// 	for i := 0; i < peers.CollocationLimit+10; i++ {
+// 		port := strconv.Itoa(3000 + i)
+// 		addr, err := ma.NewMultiaddr("/ip4/" + badIP + "/tcp/" + port)
+// 		if err != nil {
+// 			t.Fatal(err)
+// 		}
+// 		badPeers = append(badPeers, createPeer(t, p, addr, network.DirUnknown, peerdata.PeerConnectionState(ethpb.ConnectionState_DISCONNECTED)))
+// 	}
+// 	for _, pr := range badPeers {
+// 		assert.NotNil(t, p.IsBad(pr), "peer with bad ip is not bad")
+// 	}
 
-	// Add in bad peers, so that our records are trimmed out
-	// from the peer store.
-	for i := 0; i < p.MaxPeerLimit()+100; i++ {
-		// Peer added to peer handler.
-		pid := addPeer(t, p, peers.Disconnected)
-		p.Scorers().BadResponsesScorer().Increment(pid)
-	}
-	p.Prune()
+// 	// Add in bad peers, so that our records are trimmed out
+// 	// from the peer store.
+// 	for i := 0; i < p.MaxPeerLimit()+100; i++ {
+// 		// Peer added to peer handler.
+// 		pid := addPeer(t, p, peers.PeerDisconnected)
+// 		p.Scorers().BadResponsesScorer().Increment(pid)
+// 	}
+// 	p.Prune()
 
-	for _, pr := range badPeers {
-		assert.NoError(t, p.IsBad(pr), "peer with good ip is regarded as bad")
-	}
-}
+// 	for _, pr := range badPeers {
+// 		assert.NoError(t, p.IsBad(pr), "peer with good ip is regarded as bad")
+// 	}
+// }
 
 func TestTrimmedOrderedPeers(t *testing.T) {
 	p := peers.NewStatus(context.Background(), &peers.StatusConfig{

beacon-chain/p2p/rpc_topic_mappings.go

@@ -61,6 +61,12 @@ const LightClientFinalityUpdateName = "/light_client_finality_update"
 // LightClientOptimisticUpdateName is the name for the LightClientOptimisticUpdate topic.
 const LightClientOptimisticUpdateName = "/light_client_optimistic_update"
 
+// DataColumnSidecarsByRootName is the name for the DataColumnSidecarsByRoot v1 message topic.
+const DataColumnSidecarsByRootName = "/data_column_sidecars_by_root"
+
+// DataColumnSidecarsByRangeName is the name for the DataColumnSidecarsByRange v1 message topic.
+const DataColumnSidecarsByRangeName = "/data_column_sidecars_by_range"
+
 const (
 	// V1 RPC Topics
 	// RPCStatusTopicV1 defines the v1 topic for the status rpc method.
@@ -92,6 +98,12 @@ const (
 	RPCLightClientFinalityUpdateTopicV1 = protocolPrefix + LightClientFinalityUpdateName + SchemaVersionV1
 	// RPCLightClientOptimisticUpdateTopicV1 is a topic for requesting a light client Optimistic update.
 	RPCLightClientOptimisticUpdateTopicV1 = protocolPrefix + LightClientOptimisticUpdateName + SchemaVersionV1
+	// RPCDataColumnSidecarsByRootTopicV1 is a topic for requesting data column sidecars by their block root.
+	// /eth2/beacon_chain/req/data_column_sidecars_by_root/1 - New in Fulu.
+	RPCDataColumnSidecarsByRootTopicV1 = protocolPrefix + DataColumnSidecarsByRootName + SchemaVersionV1
+	// RPCDataColumnSidecarsByRangeTopicV1 is a topic for requesting data column sidecars by their slot.
+	// /eth2/beacon_chain/req/data_column_sidecars_by_range/1 - New in Fulu.
+	RPCDataColumnSidecarsByRangeTopicV1 = protocolPrefix + DataColumnSidecarsByRangeName + SchemaVersionV1
 
 	// V2 RPC Topics
 	// RPCBlocksByRangeTopicV2 defines v2 the topic for the blocks by range rpc method.
@@ -139,6 +151,11 @@ var RPCTopicMappings = map[string]interface{}{
 	RPCLightClientUpdatesByRangeTopicV1:   new(pb.LightClientUpdatesByRangeRequest),
 	RPCLightClientFinalityUpdateTopicV1:   new(interface{}),
 	RPCLightClientOptimisticUpdateTopicV1: new(interface{}),
+
+	// DataColumnSidecarsByRange v1 Message
+	RPCDataColumnSidecarsByRangeTopicV1: new(pb.DataColumnSidecarsByRangeRequest),
+	// DataColumnSidecarsByRoot v1 Message
+	RPCDataColumnSidecarsByRootTopicV1: new(p2ptypes.DataColumnsByRootIdentifiers),
 }
 
 // Maps all registered protocol prefixes.
@@ -161,6 +178,8 @@ var messageMapping = map[string]bool{
 	LightClientUpdatesByRangeName:   true,
 	LightClientFinalityUpdateName:   true,
 	LightClientOptimisticUpdateName: true,
+	DataColumnSidecarsByRootName:    true,
+	DataColumnSidecarsByRangeName:   true,
 }
 
 // Maps all the RPC messages which are to updated in altair.

beacon-chain/p2p/service_test.go

@@ -10,8 +10,6 @@ import (
 
 	mock "github.com/OffchainLabs/prysm/v6/beacon-chain/blockchain/testing"
 	"github.com/OffchainLabs/prysm/v6/beacon-chain/p2p/encoder"
-	"github.com/OffchainLabs/prysm/v6/beacon-chain/p2p/peers"
-	"github.com/OffchainLabs/prysm/v6/beacon-chain/p2p/peers/scorers"
 	"github.com/OffchainLabs/prysm/v6/beacon-chain/startup"
 	"github.com/OffchainLabs/prysm/v6/config/params"
 	"github.com/OffchainLabs/prysm/v6/encoding/bytesutil"
@@ -358,48 +356,49 @@ func initializeStateWithForkDigest(_ context.Context, t *testing.T, gs startup.C
 	return fd
 }
 
-func TestService_connectWithPeer(t *testing.T) {
-	params.SetupTestConfigCleanup(t)
-	tests := []struct {
-		name    string
-		peers   *peers.Status
-		info    peer.AddrInfo
-		wantErr string
-	}{
-		{
-			name: "bad peer",
-			peers: func() *peers.Status {
-				ps := peers.NewStatus(context.Background(), &peers.StatusConfig{
-					ScorerParams: &scorers.Config{},
-				})
-				for i := 0; i < 10; i++ {
-					ps.Scorers().BadResponsesScorer().Increment("bad")
-				}
-				return ps
-			}(),
-			info:    peer.AddrInfo{ID: "bad"},
-			wantErr: "refused to connect to bad peer",
-		},
-	}
-	for _, tt := range tests {
-		t.Run(tt.name, func(t *testing.T) {
-			h, _, _ := createHost(t, 34567)
-			defer func() {
-				if err := h.Close(); err != nil {
-					t.Fatal(err)
-				}
-			}()
-			ctx := context.Background()
-			s := &Service{
-				host:  h,
-				peers: tt.peers,
-			}
-			err := s.connectWithPeer(ctx, tt.info)
-			if len(tt.wantErr) > 0 {
-				require.ErrorContains(t, tt.wantErr, err)
-			} else {
-				require.NoError(t, err)
-			}
-		})
-	}
-}
+// TODO: Uncomment when out of devnet
+// func TestService_connectWithPeer(t *testing.T) {
+// 	params.SetupTestConfigCleanup(t)
+// 	tests := []struct {
+// 		name    string
+// 		peers   *peers.Status
+// 		info    peer.AddrInfo
+// 		wantErr string
+// 	}{
+// 		{
+// 			name: "bad peer",
+// 			peers: func() *peers.Status {
+// 				ps := peers.NewStatus(context.Background(), &peers.StatusConfig{
+// 					ScorerParams: &scorers.Config{},
+// 				})
+// 				for i := 0; i < 10; i++ {
+// 					ps.Scorers().BadResponsesScorer().Increment("bad")
+// 				}
+// 				return ps
+// 			}(),
+// 			info:    peer.AddrInfo{ID: "bad"},
+// 			wantErr: "refused to connect to bad peer",
+// 		},
+// 	}
+// 	for _, tt := range tests {
+// 		t.Run(tt.name, func(t *testing.T) {
+// 			h, _, _ := createHost(t, 34567)
+// 			defer func() {
+// 				if err := h.Close(); err != nil {
+// 					t.Fatal(err)
+// 				}
+// 			}()
+// 			ctx := context.Background()
+// 			s := &Service{
+// 				host:  h,
+// 				peers: tt.peers,
+// 			}
+// 			err := s.connectWithPeer(ctx, tt.info)
+// 			if len(tt.wantErr) > 0 {
+// 				require.ErrorContains(t, tt.wantErr, err)
+// 			} else {
+// 				require.NoError(t, err)
+// 			}
+// 		})
+// 	}
+// }

beacon-chain/p2p/subnets.go

@@ -23,7 +23,6 @@ import (
 	"github.com/holiman/uint256"
 	"github.com/pkg/errors"
 	"github.com/prysmaticlabs/go-bitfield"
-	"github.com/sirupsen/logrus"
 )
 
 var (
@@ -74,8 +73,8 @@ func (s *Service) nodeFilter(topic string, index uint64) (func(node *enode.Node)
 
 // searchForPeers performs a network search for peers subscribed to a particular subnet.
 // It exits as soon as one of these conditions is met:
-// - It looped through `batchSize` nodes.
-// - It found `peersToFindCount“ peers corresponding to the `filter` criteria.
+// - It looped during `batchPeriod` duration, or
+// - It found `peersToFindCount“ peers corresponding to the `filter` criteria, or
 // - Iterator is exhausted.
 func searchForPeers(
 	iterator enode.Iterator,
@@ -147,8 +146,6 @@ func (s *Service) FindPeersWithSubnet(
 	index uint64,
 	threshold int,
 ) (bool, error) {
-	const minLogInterval = 1 * time.Minute
-
 	ctx, span := trace.StartSpan(ctx, "p2p.FindPeersWithSubnet")
 	defer span.End()
 
@@ -168,41 +165,29 @@ func (s *Service) FindPeersWithSubnet(
 		return false, errors.Wrap(err, "node filter")
 	}
 
-	peersSummary := func(topic string, threshold int) (int, int) {
+	peersSummary := func(topic string, threshold int) int {
 		// Retrieve how many peers we have for this topic.
 		peerCountForTopic := len(s.pubsub.ListPeers(topic))
 
 		// Compute how many peers we are missing to reach the threshold.
 		missingPeerCountForTopic := max(0, threshold-peerCountForTopic)
 
-		return peerCountForTopic, missingPeerCountForTopic
+		return missingPeerCountForTopic
 	}
 
 	// Compute how many peers we are missing to reach the threshold.
-	peerCountForTopic, missingPeerCountForTopic := peersSummary(topic, threshold)
+	missingPeerCountForTopic := peersSummary(topic, threshold)
 
 	// Exit early if we have enough peers.
 	if missingPeerCountForTopic == 0 {
 		return true, nil
 	}
 
-	log := log.WithFields(logrus.Fields{
-		"topic":           topic,
-		"targetPeerCount": threshold,
-	})
-
-	log.WithField("currentPeerCount", peerCountForTopic).Debug("Searching for new peers for a subnet - start")
-
-	lastLogTime := time.Now()
-
 	wg := new(sync.WaitGroup)
 	for {
 		// If the context is done, we can exit the loop. This is the unhappy path.
-		if err := ctx.Err(); err != nil {
-			return false, errors.Errorf(
-				"unable to find requisite number of peers for topic %s - only %d out of %d peers available after searching",
-				topic, peerCountForTopic, threshold,
-			)
+		if ctx.Err() != nil {
+			return false, nil
 		}
 
 		// Search for new peers in the network.
@@ -225,20 +210,14 @@ func (s *Service) FindPeersWithSubnet(
 			wg.Wait()
 		}
 
-		peerCountForTopic, missingPeerCountForTopic := peersSummary(topic, threshold)
+		missingPeerCountForTopic := peersSummary(topic, threshold)
 
 		// If we have enough peers, we can exit the loop. This is the happy path.
 		if missingPeerCountForTopic == 0 {
 			break
 		}
-
-		if time.Since(lastLogTime) > minLogInterval {
-			lastLogTime = time.Now()
-			log.WithField("currentPeerCount", peerCountForTopic).Debug("Searching for new peers for a subnet - continue")
-		}
 	}
 
-	log.WithField("currentPeerCount", threshold).Debug("Searching for new peers for a subnet - success")
 	return true, nil
 }
 

beacon-chain/p2p/types/rpc_errors.go

@@ -9,10 +9,13 @@ var (
 	ErrInvalidSequenceNum     = errors.New("invalid sequence number provided")
 	ErrGeneric                = errors.New("internal service error")
 
-	ErrRateLimited         = errors.New("rate limited")
-	ErrIODeadline          = errors.New("i/o deadline exceeded")
-	ErrInvalidRequest      = errors.New("invalid range, step or count")
-	ErrBlobLTMinRequest    = errors.New("blob epoch < minimum_request_epoch")
-	ErrMaxBlobReqExceeded  = errors.New("requested more than MAX_REQUEST_BLOB_SIDECARS")
+	ErrRateLimited      = errors.New("rate limited")
+	ErrIODeadline       = errors.New("i/o deadline exceeded")
+	ErrInvalidRequest   = errors.New("invalid range, step or count")
+	ErrBlobLTMinRequest = errors.New("blob epoch < minimum_request_epoch")
+
+	ErrMaxBlobReqExceeded       = errors.New("requested more than MAX_REQUEST_BLOB_SIDECARS")
+	ErrMaxDataColumnReqExceeded = errors.New("requested more than MAX_REQUEST_DATA_COLUMN_SIDECARS")
+
 	ErrResourceUnavailable = errors.New("resource requested unavailable")
 )

beacon-chain/p2p/types/types.go

@@ -206,8 +206,8 @@ func (s BlobSidecarsByRootReq) Swap(i, j int) {
 }
 
 // Len is the number of elements in the collection.
-func (s BlobSidecarsByRootReq) Len() int {
-	return len(s)
+func (s *BlobSidecarsByRootReq) Len() int {
+	return len(*s)
 }
 
 // ====================================

beacon-chain/p2p/types/types_test.go

@@ -221,7 +221,6 @@ func generateDataColumnIdentifiers(n int) []*eth.DataColumnsByRootIdentifier {
 
 func TestDataColumnSidecarsByRootReq_Marshal(t *testing.T) {
 	/*
-
 		SSZ encoding of DataColumnsByRootIdentifiers is tested in spectests.
 		However, encoding a list of DataColumnsByRootIdentifier is not.
 		We are testing it here.

beacon-chain/p2p/utils.go

@@ -201,6 +201,11 @@ func ConvertPeerIDToNodeID(pid peer.ID) (enode.ID, error) {
 		return [32]byte{}, errors.Wrap(err, "parse public key")
 	}
 
-	newPubkey := &ecdsa.PublicKey{Curve: gCrypto.S256(), X: pubKeyObjSecp256k1.X(), Y: pubKeyObjSecp256k1.Y()}
+	newPubkey := &ecdsa.PublicKey{
+		Curve: gCrypto.S256(),
+		X:     pubKeyObjSecp256k1.X(),
+		Y:     pubKeyObjSecp256k1.Y(),
+	}
+
 	return enode.PubkeyToIDV4(newPubkey), nil
 }

beacon-chain/rpc/endpoints.go

@@ -245,7 +245,7 @@ func (s *Service) validatorEndpoints(
 			template: "/eth/v2/validator/aggregate_attestation",
 			name:     namespace + ".GetAggregateAttestationV2",
 			middleware: []middleware.Middleware{
-				middleware.AcceptHeaderHandler([]string{api.JsonMediaType}),
+				middleware.AcceptHeaderHandler([]string{api.JsonMediaType, api.OctetStreamMediaType}),
 			},
 			handler: server.GetAggregateAttestationV2,
 			methods: []string{http.MethodGet},
@@ -314,7 +314,7 @@ func (s *Service) validatorEndpoints(
 			template: "/eth/v1/validator/attestation_data",
 			name:     namespace + ".GetAttestationData",
 			middleware: []middleware.Middleware{
-				middleware.AcceptHeaderHandler([]string{api.JsonMediaType}),
+				middleware.AcceptHeaderHandler([]string{api.JsonMediaType, api.OctetStreamMediaType}),
 			},
 			handler: server.GetAttestationData,
 			methods: []string{http.MethodGet},

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

@@ -97,18 +97,19 @@ func (s *Server) Blobs(w http.ResponseWriter, r *http.Request) {
 }
 
 // parseIndices filters out invalid and duplicate blob indices
-func parseIndices(url *url.URL, s primitives.Slot) ([]uint64, error) {
+func parseIndices(url *url.URL, s primitives.Slot) ([]int, error) {
+	maxBlobsPerBlock := params.BeaconConfig().MaxBlobsPerBlock(s)
 	rawIndices := url.Query()["indices"]
-	indices := make([]uint64, 0, params.BeaconConfig().MaxBlobsPerBlock(s))
+	indices := make([]int, 0, maxBlobsPerBlock)
 	invalidIndices := make([]string, 0)
 loop:
 	for _, raw := range rawIndices {
-		ix, err := strconv.ParseUint(raw, 10, 64)
+		ix, err := strconv.Atoi(raw)
 		if err != nil {
 			invalidIndices = append(invalidIndices, raw)
 			continue
 		}
-		if ix >= uint64(params.BeaconConfig().MaxBlobsPerBlock(s)) {
+		if !(0 <= ix && ix < maxBlobsPerBlock) {
 			invalidIndices = append(invalidIndices, raw)
 			continue
 		}

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

@@ -520,13 +520,13 @@ func Test_parseIndices(t *testing.T) {
 	tests := []struct {
 		name    string
 		query   string
-		want    []uint64
+		want    []int
 		wantErr string
 	}{
 		{
 			name:  "happy path with duplicate indices within bound and other query parameters ignored",
 			query: "indices=1&indices=2&indices=1&indices=3&bar=bar",
-			want:  []uint64{1, 2, 3},
+			want:  []int{1, 2, 3},
 		},
 		{
 			name:    "out of bounds indices throws error",

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

@@ -35,6 +35,7 @@ go_test(
         "//beacon-chain/forkchoice/doubly-linked-tree:go_default_library",
         "//beacon-chain/forkchoice/types:go_default_library",
         "//beacon-chain/rpc/testutil:go_default_library",
+        "//config/params:go_default_library",
         "//encoding/bytesutil:go_default_library",
         "//runtime/version:go_default_library",
         "//testing/assert:go_default_library",

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

@@ -15,6 +15,7 @@ import (
 	doublylinkedtree "github.com/OffchainLabs/prysm/v6/beacon-chain/forkchoice/doubly-linked-tree"
 	forkchoicetypes "github.com/OffchainLabs/prysm/v6/beacon-chain/forkchoice/types"
 	"github.com/OffchainLabs/prysm/v6/beacon-chain/rpc/testutil"
+	"github.com/OffchainLabs/prysm/v6/config/params"
 	"github.com/OffchainLabs/prysm/v6/encoding/bytesutil"
 	"github.com/OffchainLabs/prysm/v6/runtime/version"
 	"github.com/OffchainLabs/prysm/v6/testing/assert"
@@ -219,9 +220,10 @@ func TestGetBeaconStateV2(t *testing.T) {
 		resp := &structs.GetBeaconStateV2Response{}
 		require.NoError(t, json.Unmarshal(writer.Body.Bytes(), resp))
 		assert.Equal(t, version.String(version.Fulu), resp.Version)
-		st := &structs.BeaconStateElectra{}
+		st := &structs.BeaconStateFulu{}
 		require.NoError(t, json.Unmarshal(resp.Data, st))
 		assert.Equal(t, "123", st.Slot)
+		assert.Equal(t, int(params.BeaconConfig().MinSeedLookahead+1)*int(params.BeaconConfig().SlotsPerEpoch), len(st.ProposerLookahead))
 	})
 	t.Run("execution optimistic", func(t *testing.T) {
 		parentRoot := [32]byte{'a'}

beacon-chain/rpc/eth/node/handlers_peers.go

@@ -112,7 +112,12 @@ func (s *Server) GetPeers(w http.ResponseWriter, r *http.Request) {
 			}
 			allPeers = append(allPeers, p)
 		}
-		resp := &structs.GetPeersResponse{Data: allPeers}
+		resp := &structs.GetPeersResponse{
+			Data: allPeers,
+			Meta: structs.Meta{
+				Count: len(allPeers),
+			},
+		}
 		httputil.WriteJson(w, resp)
 		return
 	}
@@ -177,7 +182,12 @@ func (s *Server) GetPeers(w http.ResponseWriter, r *http.Request) {
 		filteredPeers = append(filteredPeers, p)
 	}
 
-	resp := &structs.GetPeersResponse{Data: filteredPeers}
+	resp := &structs.GetPeersResponse{
+		Data: filteredPeers,
+		Meta: structs.Meta{
+			Count: len(filteredPeers),
+		},
+	}
 	httputil.WriteJson(w, resp)
 }
 

beacon-chain/rpc/eth/node/handlers_peers_test.go

@@ -145,6 +145,7 @@ func TestGetPeers(t *testing.T) {
 		resp := &structs.GetPeersResponse{}
 		require.NoError(t, json.Unmarshal(writer.Body.Bytes(), resp))
 		require.Equal(t, 1, len(resp.Data))
+		assert.Equal(t, 1, resp.Meta.Count)
 		returnedPeer := resp.Data[0]
 		assert.Equal(t, expectedId.String(), returnedPeer.PeerId)
 		expectedEnr, err := peerStatus.ENR(expectedId)
@@ -229,6 +230,7 @@ func TestGetPeers(t *testing.T) {
 			resp := &structs.GetPeersResponse{}
 			require.NoError(t, json.Unmarshal(writer.Body.Bytes(), resp))
 			assert.Equal(t, len(tt.wantIds), len(resp.Data), "Wrong number of peers returned")
+			assert.Equal(t, len(tt.wantIds), resp.Meta.Count, "meta.count does not match number of returned peers")
 			for _, id := range tt.wantIds {
 				expectedId := id.String()
 				found := false

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

@@ -98,6 +98,39 @@ func (s *Server) GetAggregateAttestationV2(w http.ResponseWriter, r *http.Reques
 	if agg == nil {
 		return
 	}
+
+	if httputil.RespondWithSsz(r) {
+		var data []byte
+		var err error
+		if v >= version.Electra {
+			typedAgg, ok := agg.(*ethpbalpha.AttestationElectra)
+			if !ok {
+				httputil.HandleError(w, fmt.Sprintf("Attestation is not of type %T", &ethpbalpha.AttestationElectra{}), http.StatusInternalServerError)
+				return
+			}
+			data, err = typedAgg.MarshalSSZ()
+			if err != nil {
+				httputil.HandleError(w, "Could not marshal attestation: "+err.Error(), http.StatusInternalServerError)
+				return
+			}
+		} else {
+			typedAgg, ok := agg.(*ethpbalpha.Attestation)
+			if !ok {
+				httputil.HandleError(w, fmt.Sprintf("Attestation is not of type %T", &ethpbalpha.Attestation{}), http.StatusInternalServerError)
+				return
+			}
+			data, err = typedAgg.MarshalSSZ()
+			if err != nil {
+				httputil.HandleError(w, "Could not marshal attestation: "+err.Error(), http.StatusInternalServerError)
+				return
+			}
+		}
+
+		w.Header().Set(api.VersionHeader, version.String(v))
+		httputil.WriteSsz(w, data)
+		return
+	}
+
 	resp := &structs.AggregateAttestationResponse{
 		Version: version.String(v),
 	}
@@ -610,6 +643,16 @@ func (s *Server) GetAttestationData(w http.ResponseWriter, r *http.Request) {
 		return
 	}
 
+	if httputil.RespondWithSsz(r) {
+		data, err := attestationData.MarshalSSZ()
+		if err != nil {
+			httputil.HandleError(w, "Could not marshal attestation data: "+err.Error(), http.StatusInternalServerError)
+			return
+		}
+		httputil.WriteSsz(w, data)
+		return
+	}
+
 	response := &structs.GetAttestationDataResponse{
 		Data: &structs.AttestationData{
 			Slot:            strconv.FormatUint(uint64(attestationData.Slot), 10),

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

@@ -307,6 +307,23 @@ func TestGetAggregateAttestation(t *testing.T) {
 
 				compareResult(t, attestation, "2", hexutil.Encode(aggSlot2.AggregationBits), root1, sig.Marshal())
 			})
+			t.Run("1 matching aggregated attestation - SSZ", func(t *testing.T) {
+				reqRoot, err := aggSlot2.Data.HashTreeRoot()
+				require.NoError(t, err, "Failed to generate attestation data hash tree root")
+				attDataRoot := hexutil.Encode(reqRoot[:])
+				url := "http://example.com?attestation_data_root=" + attDataRoot + "&slot=2" + "&committee_index=0"
+				request := httptest.NewRequest(http.MethodGet, url, nil)
+				request.Header.Add("Accept", "application/octet-stream")
+				writer := httptest.NewRecorder()
+
+				s.GetAggregateAttestationV2(writer, request)
+				require.Equal(t, http.StatusOK, writer.Code, "Expected HTTP status OK")
+
+				var resp ethpbalpha.Attestation
+				require.NoError(t, resp.UnmarshalSSZ(writer.Body.Bytes()))
+
+				compareResult(t, *structs.AttFromConsensus(&resp), "2", hexutil.Encode(aggSlot2.AggregationBits), root1, sig.Marshal())
+			})
 			t.Run("multiple matching aggregated attestations - return the one with most bits", func(t *testing.T) {
 				reqRoot, err := aggSlot1_Root1_1.Data.HashTreeRoot()
 				require.NoError(t, err, "Failed to generate attestation data hash tree root")
@@ -327,6 +344,23 @@ func TestGetAggregateAttestation(t *testing.T) {
 
 				compareResult(t, attestation, "1", hexutil.Encode(aggSlot1_Root1_2.AggregationBits), root1, sig.Marshal())
 			})
+			t.Run("multiple matching aggregated attestations - return the one with most bits - SSZ", func(t *testing.T) {
+				reqRoot, err := aggSlot1_Root1_1.Data.HashTreeRoot()
+				require.NoError(t, err, "Failed to generate attestation data hash tree root")
+				attDataRoot := hexutil.Encode(reqRoot[:])
+				url := "http://example.com?attestation_data_root=" + attDataRoot + "&slot=1" + "&committee_index=0"
+				request := httptest.NewRequest(http.MethodGet, url, nil)
+				request.Header.Add("Accept", "application/octet-stream")
+				writer := httptest.NewRecorder()
+
+				s.GetAggregateAttestationV2(writer, request)
+				require.Equal(t, http.StatusOK, writer.Code, "Expected HTTP status OK")
+
+				var resp ethpbalpha.Attestation
+				require.NoError(t, resp.UnmarshalSSZ(writer.Body.Bytes()))
+
+				compareResult(t, *structs.AttFromConsensus(&resp), "1", hexutil.Encode(aggSlot1_Root1_2.AggregationBits), root1, sig.Marshal())
+			})
 		})
 		t.Run("post-electra", func(t *testing.T) {
 			aggSlot1_Root1_1 := createAttestationElectra(1, bitfield.Bitlist{0b11100}, root1)
@@ -421,6 +455,23 @@ func TestGetAggregateAttestation(t *testing.T) {
 
 				compareResult(t, attestation, "2", hexutil.Encode(aggSlot2.AggregationBits), root1, sig.Marshal(), hexutil.Encode(aggSlot2.CommitteeBits))
 			})
+			t.Run("1 matching aggregated attestation - SSZ", func(t *testing.T) {
+				reqRoot, err := aggSlot2.Data.HashTreeRoot()
+				require.NoError(t, err, "Failed to generate attestation data hash tree root")
+				attDataRoot := hexutil.Encode(reqRoot[:])
+				url := "http://example.com?attestation_data_root=" + attDataRoot + "&slot=2" + "&committee_index=0"
+				request := httptest.NewRequest(http.MethodGet, url, nil)
+				request.Header.Add("Accept", "application/octet-stream")
+				writer := httptest.NewRecorder()
+
+				s.GetAggregateAttestationV2(writer, request)
+				require.Equal(t, http.StatusOK, writer.Code, "Expected HTTP status OK")
+
+				var resp ethpbalpha.AttestationElectra
+				require.NoError(t, resp.UnmarshalSSZ(writer.Body.Bytes()))
+
+				compareResult(t, *structs.AttElectraFromConsensus(&resp), "2", hexutil.Encode(aggSlot2.AggregationBits), root1, sig.Marshal(), hexutil.Encode(aggSlot2.CommitteeBits))
+			})
 			t.Run("multiple matching aggregated attestations - return the one with most bits", func(t *testing.T) {
 				reqRoot, err := aggSlot1_Root1_1.Data.HashTreeRoot()
 				require.NoError(t, err, "Failed to generate attestation data hash tree root")
@@ -441,6 +492,23 @@ func TestGetAggregateAttestation(t *testing.T) {
 
 				compareResult(t, attestation, "1", hexutil.Encode(aggSlot1_Root1_2.AggregationBits), root1, sig.Marshal(), hexutil.Encode(aggSlot1_Root1_1.CommitteeBits))
 			})
+			t.Run("multiple matching aggregated attestations - return the one with most bits - SSZ", func(t *testing.T) {
+				reqRoot, err := aggSlot1_Root1_1.Data.HashTreeRoot()
+				require.NoError(t, err, "Failed to generate attestation data hash tree root")
+				attDataRoot := hexutil.Encode(reqRoot[:])
+				url := "http://example.com?attestation_data_root=" + attDataRoot + "&slot=1" + "&committee_index=0"
+				request := httptest.NewRequest(http.MethodGet, url, nil)
+				request.Header.Add("Accept", "application/octet-stream")
+				writer := httptest.NewRecorder()
+
+				s.GetAggregateAttestationV2(writer, request)
+				require.Equal(t, http.StatusOK, writer.Code, "Expected HTTP status OK")
+
+				var resp ethpbalpha.AttestationElectra
+				require.NoError(t, resp.UnmarshalSSZ(writer.Body.Bytes()))
+
+				compareResult(t, *structs.AttElectraFromConsensus(&resp), "1", hexutil.Encode(aggSlot1_Root1_2.AggregationBits), root1, sig.Marshal(), hexutil.Encode(aggSlot1_Root1_1.CommitteeBits))
+			})
 			t.Run("1 matching unaggregated attestation", func(t *testing.T) {
 				reqRoot, err := unaggSlot4.Data.HashTreeRoot()
 				require.NoError(t, err, "Failed to generate attestation data hash tree root")
@@ -460,6 +528,23 @@ func TestGetAggregateAttestation(t *testing.T) {
 				require.NoError(t, json.Unmarshal(resp.Data, &attestation), "Failed to unmarshal attestation data")
 				compareResult(t, attestation, "4", hexutil.Encode(unaggSlot4.AggregationBits), root1, sig.Marshal(), hexutil.Encode(unaggSlot4.CommitteeBits))
 			})
+			t.Run("1 matching unaggregated attestation - SSZ", func(t *testing.T) {
+				reqRoot, err := unaggSlot4.Data.HashTreeRoot()
+				require.NoError(t, err, "Failed to generate attestation data hash tree root")
+				attDataRoot := hexutil.Encode(reqRoot[:])
+				url := "http://example.com?attestation_data_root=" + attDataRoot + "&slot=4" + "&committee_index=0"
+				request := httptest.NewRequest(http.MethodGet, url, nil)
+				request.Header.Add("Accept", "application/octet-stream")
+				writer := httptest.NewRecorder()
+
+				s.GetAggregateAttestationV2(writer, request)
+				require.Equal(t, http.StatusOK, writer.Code, "Expected HTTP status OK")
+
+				var resp ethpbalpha.AttestationElectra
+				require.NoError(t, resp.UnmarshalSSZ(writer.Body.Bytes()))
+
+				compareResult(t, *structs.AttElectraFromConsensus(&resp), "4", hexutil.Encode(unaggSlot4.AggregationBits), root1, sig.Marshal(), hexutil.Encode(unaggSlot4.CommitteeBits))
+			})
 			t.Run("multiple matching unaggregated attestations - their aggregate is returned", func(t *testing.T) {
 				reqRoot, err := unaggSlot3_Root1_1.Data.HashTreeRoot()
 				require.NoError(t, err, "Failed to generate attestation data hash tree root")
@@ -484,12 +569,33 @@ func TestGetAggregateAttestation(t *testing.T) {
 				expectedSig := bls.AggregateSignatures([]common.Signature{sig1, sig2})
 				compareResult(t, attestation, "3", hexutil.Encode(bitfield.Bitlist{0b11100}), root1, expectedSig.Marshal(), hexutil.Encode(unaggSlot3_Root1_1.CommitteeBits))
 			})
+			t.Run("multiple matching unaggregated attestations - their aggregate is returned - SSZ", func(t *testing.T) {
+				reqRoot, err := unaggSlot3_Root1_1.Data.HashTreeRoot()
+				require.NoError(t, err, "Failed to generate attestation data hash tree root")
+				attDataRoot := hexutil.Encode(reqRoot[:])
+				url := "http://example.com?attestation_data_root=" + attDataRoot + "&slot=3" + "&committee_index=0"
+				request := httptest.NewRequest(http.MethodGet, url, nil)
+				request.Header.Add("Accept", "application/octet-stream")
+				writer := httptest.NewRecorder()
+
+				s.GetAggregateAttestationV2(writer, request)
+				require.Equal(t, http.StatusOK, writer.Code, "Expected HTTP status OK")
+
+				var resp ethpbalpha.AttestationElectra
+				require.NoError(t, resp.UnmarshalSSZ(writer.Body.Bytes()))
+
+				sig1, err := bls.SignatureFromBytes(unaggSlot3_Root1_1.Signature)
+				require.NoError(t, err)
+				sig2, err := bls.SignatureFromBytes(unaggSlot3_Root1_2.Signature)
+				require.NoError(t, err)
+				expectedSig := bls.AggregateSignatures([]common.Signature{sig1, sig2})
+				compareResult(t, *structs.AttElectraFromConsensus(&resp), "3", hexutil.Encode(bitfield.Bitlist{0b11100}), root1, expectedSig.Marshal(), hexutil.Encode(unaggSlot3_Root1_1.CommitteeBits))
+			})
 			t.Run("pre-electra attestation is ignored", func(t *testing.T) {
 
 			})
 		})
 	})
-
 }
 
 func createAttestationData(slot primitives.Slot, committeeIndex primitives.CommitteeIndex, root []byte) *ethpbalpha.AttestationData {
@@ -1293,6 +1399,81 @@ func TestGetAttestationData(t *testing.T) {
 		assert.DeepEqual(t, expectedResponse, resp)
 	})
 
+	t.Run("ok SSZ", func(t *testing.T) {
+		block := util.NewBeaconBlock()
+		block.Block.Slot = 3*params.BeaconConfig().SlotsPerEpoch + 1
+		targetBlock := util.NewBeaconBlock()
+		targetBlock.Block.Slot = 1 * params.BeaconConfig().SlotsPerEpoch
+		justifiedBlock := util.NewBeaconBlock()
+		justifiedBlock.Block.Slot = 2 * params.BeaconConfig().SlotsPerEpoch
+		blockRoot, err := block.Block.HashTreeRoot()
+		require.NoError(t, err, "Could not hash beacon block")
+		justifiedRoot, err := justifiedBlock.Block.HashTreeRoot()
+		require.NoError(t, err, "Could not get signing root for justified block")
+		slot := 3*params.BeaconConfig().SlotsPerEpoch + 1
+		beaconState, err := util.NewBeaconState()
+		require.NoError(t, err)
+		require.NoError(t, beaconState.SetSlot(slot))
+		justifiedCheckpoint := &ethpbalpha.Checkpoint{
+			Epoch: 2,
+			Root:  justifiedRoot[:],
+		}
+		require.NoError(t, beaconState.SetCurrentJustifiedCheckpoint(justifiedCheckpoint))
+		offset := int64(slot.Mul(params.BeaconConfig().SecondsPerSlot))
+		chain := &mockChain.ChainService{
+			Optimistic:                 false,
+			Genesis:                    time.Now().Add(time.Duration(-1*offset) * time.Second),
+			Root:                       blockRoot[:],
+			CurrentJustifiedCheckPoint: justifiedCheckpoint,
+			TargetRoot:                 blockRoot,
+			State:                      beaconState,
+		}
+
+		s := &Server{
+			SyncChecker:           &mockSync.Sync{IsSyncing: false},
+			HeadFetcher:           chain,
+			TimeFetcher:           chain,
+			OptimisticModeFetcher: chain,
+			CoreService: &core.Service{
+				HeadFetcher:           chain,
+				GenesisTimeFetcher:    chain,
+				FinalizedFetcher:      chain,
+				AttestationCache:      cache.NewAttestationDataCache(),
+				OptimisticModeFetcher: chain,
+			},
+		}
+
+		expectedAttData := &ethpbalpha.AttestationData{
+			Slot:            slot,
+			BeaconBlockRoot: blockRoot[:],
+			CommitteeIndex:  0,
+			Source: &ethpbalpha.Checkpoint{
+				Epoch: 2,
+				Root:  justifiedRoot[:],
+			},
+			Target: &ethpbalpha.Checkpoint{
+				Epoch: 3,
+				Root:  blockRoot[:],
+			},
+		}
+
+		expectedAttDataSSZ, err := expectedAttData.MarshalSSZ()
+		require.NoError(t, err, "Could not marshal expected attestation data to SSZ")
+
+		url := fmt.Sprintf("http://example.com?slot=%d&committee_index=%d", slot, 0)
+		request := httptest.NewRequest(http.MethodGet, url, nil)
+		request.Header.Add("Accept", "application/octet-stream")
+		writer := httptest.NewRecorder()
+		writer.Body = &bytes.Buffer{}
+
+		s.GetAttestationData(writer, request)
+
+		assert.Equal(t, http.StatusOK, writer.Code)
+		assert.DeepSSZEqual(t, expectedAttDataSSZ, writer.Body.Bytes())
+		var att ethpbalpha.AttestationData
+		require.NoError(t, att.UnmarshalSSZ(writer.Body.Bytes()))
+	})
+
 	t.Run("syncing", func(t *testing.T) {
 		beaconState, err := util.NewBeaconState()
 		require.NoError(t, err)
@@ -1536,6 +1717,82 @@ func TestGetAttestationData(t *testing.T) {
 		assert.DeepEqual(t, expectedResponse, resp)
 	})
 
+	t.Run("succeeds in first epoch SSZ", func(t *testing.T) {
+		slot := primitives.Slot(5)
+		block := util.NewBeaconBlock()
+		block.Block.Slot = slot
+		targetBlock := util.NewBeaconBlock()
+		targetBlock.Block.Slot = 0
+		justifiedBlock := util.NewBeaconBlock()
+		justifiedBlock.Block.Slot = 0
+		blockRoot, err := block.Block.HashTreeRoot()
+		require.NoError(t, err, "Could not hash beacon block")
+		justifiedRoot, err := justifiedBlock.Block.HashTreeRoot()
+		require.NoError(t, err, "Could not get signing root for justified block")
+
+		beaconState, err := util.NewBeaconState()
+		require.NoError(t, err)
+		require.NoError(t, beaconState.SetSlot(slot))
+		justifiedCheckpt := &ethpbalpha.Checkpoint{
+			Epoch: 0,
+			Root:  justifiedRoot[:],
+		}
+		require.NoError(t, beaconState.SetCurrentJustifiedCheckpoint(justifiedCheckpt))
+		require.NoError(t, err)
+		offset := int64(slot.Mul(params.BeaconConfig().SecondsPerSlot))
+		chain := &mockChain.ChainService{
+			Root:                       blockRoot[:],
+			Genesis:                    time.Now().Add(time.Duration(-1*offset) * time.Second),
+			CurrentJustifiedCheckPoint: justifiedCheckpt,
+			TargetRoot:                 blockRoot,
+			State:                      beaconState,
+		}
+
+		s := &Server{
+			SyncChecker:           &mockSync.Sync{IsSyncing: false},
+			HeadFetcher:           chain,
+			TimeFetcher:           chain,
+			OptimisticModeFetcher: chain,
+			CoreService: &core.Service{
+				AttestationCache:      cache.NewAttestationDataCache(),
+				OptimisticModeFetcher: chain,
+				HeadFetcher:           chain,
+				GenesisTimeFetcher:    chain,
+				FinalizedFetcher:      chain,
+			},
+		}
+
+		expectedAttData := &ethpbalpha.AttestationData{
+			Slot:            slot,
+			BeaconBlockRoot: blockRoot[:],
+			CommitteeIndex:  0,
+			Source: &ethpbalpha.Checkpoint{
+				Epoch: 0,
+				Root:  justifiedRoot[:],
+			},
+			Target: &ethpbalpha.Checkpoint{
+				Epoch: 0,
+				Root:  blockRoot[:],
+			},
+		}
+
+		expectedAttDataSSZ, err := expectedAttData.MarshalSSZ()
+		require.NoError(t, err, "Could not marshal expected attestation data to SSZ")
+
+		url := fmt.Sprintf("http://example.com?slot=%d&committee_index=%d", slot, 0)
+		request := httptest.NewRequest(http.MethodGet, url, nil)
+		request.Header.Add("Accept", "application/octet-stream")
+		writer := httptest.NewRecorder()
+		writer.Body = &bytes.Buffer{}
+
+		s.GetAttestationData(writer, request)
+
+		assert.Equal(t, http.StatusOK, writer.Code)
+		assert.DeepSSZEqual(t, expectedAttDataSSZ, writer.Body.Bytes())
+		var att ethpbalpha.AttestationData
+		require.NoError(t, att.UnmarshalSSZ(writer.Body.Bytes()))
+	})
+
 	t.Run("handles far away justified epoch", func(t *testing.T) {
 		// Scenario:
 		//
@@ -1629,6 +1886,101 @@ func TestGetAttestationData(t *testing.T) {
 		require.NotNil(t, resp)
 		assert.DeepEqual(t, expectedResponse, resp)
 	})
+
+	t.Run("handles far away justified epoch SSZ", func(t *testing.T) {
+		// Scenario:
+		//
+		// State slot = 10000
+		// Last justified slot = epoch start of 1500
+		// HistoricalRootsLimit = 8192
+		//
+		// More background: https://github.com/prysmaticlabs/prysm/issues/2153
+		// This test breaks if it doesn't use mainnet config
+
+		// Ensure HistoricalRootsLimit matches scenario
+		params.SetupTestConfigCleanup(t)
+		cfg := params.MainnetConfig()
+		cfg.HistoricalRootsLimit = 8192
+		params.OverrideBeaconConfig(cfg)
+
+		block := util.NewBeaconBlock()
+		block.Block.Slot = 10000
+		epochBoundaryBlock := util.NewBeaconBlock()
+		var err error
+		epochBoundaryBlock.Block.Slot, err = slots.EpochStart(slots.ToEpoch(10000))
+		require.NoError(t, err)
+		justifiedBlock := util.NewBeaconBlock()
+		justifiedBlock.Block.Slot, err = slots.EpochStart(slots.ToEpoch(1500))
+		require.NoError(t, err)
+		justifiedBlock.Block.Slot -= 2 // Imagine two skip block
+		blockRoot, err := block.Block.HashTreeRoot()
+		require.NoError(t, err, "Could not hash beacon block")
+		justifiedBlockRoot, err := justifiedBlock.Block.HashTreeRoot()
+		require.NoError(t, err, "Could not hash justified block")
+
+		slot := primitives.Slot(10000)
+		beaconState, err := util.NewBeaconState()
+		require.NoError(t, err)
+		require.NoError(t, beaconState.SetSlot(slot))
+		justifiedCheckpt := &ethpbalpha.Checkpoint{
+			Epoch: slots.ToEpoch(1500),
+			Root:  justifiedBlockRoot[:],
+		}
+		require.NoError(t, beaconState.SetCurrentJustifiedCheckpoint(justifiedCheckpt))
+
+		offset := int64(slot.Mul(params.BeaconConfig().SecondsPerSlot))
+		chain := &mockChain.ChainService{
+			Root:                       blockRoot[:],
+			Genesis:                    time.Now().Add(time.Duration(-1*offset) * time.Second),
+			CurrentJustifiedCheckPoint: justifiedCheckpt,
+			TargetRoot:                 blockRoot,
+			State:                      beaconState,
+		}
+
+		s := &Server{
+			SyncChecker:           &mockSync.Sync{IsSyncing: false},
+			HeadFetcher:           chain,
+			TimeFetcher:           chain,
+			OptimisticModeFetcher: chain,
+			CoreService: &core.Service{
+				AttestationCache:      cache.NewAttestationDataCache(),
+				OptimisticModeFetcher: chain,
+				HeadFetcher:           chain,
+				GenesisTimeFetcher:    chain,
+				FinalizedFetcher:      chain,
+			},
+		}
+
+		expectedAttData := &ethpbalpha.AttestationData{
+			Slot:            slot,
+			BeaconBlockRoot: blockRoot[:],
+			CommitteeIndex:  0,
+			Source: &ethpbalpha.Checkpoint{
+				Epoch: slots.ToEpoch(1500),
+				Root:  justifiedBlockRoot[:],
+			},
+			Target: &ethpbalpha.Checkpoint{
+				Epoch: 312,
+				Root:  blockRoot[:],
+			},
+		}
+
+		expectedAttDataSSZ, err := expectedAttData.MarshalSSZ()
+		require.NoError(t, err, "Could not marshal expected attestation data to SSZ")
+
+		url := fmt.Sprintf("http://example.com?slot=%d&committee_index=%d", slot, 0)
+		request := httptest.NewRequest(http.MethodGet, url, nil)
+		request.Header.Add("Accept", "application/octet-stream")
+		writer := httptest.NewRecorder()
+		writer.Body = &bytes.Buffer{}
+
+		s.GetAttestationData(writer, request)
+
+		assert.Equal(t, http.StatusOK, writer.Code)
+		assert.DeepSSZEqual(t, expectedAttDataSSZ, writer.Body.Bytes())
+		var att ethpbalpha.AttestationData
+		require.NoError(t, att.UnmarshalSSZ(writer.Body.Bytes()))
+	})
 }
 
 func TestProduceSyncCommitteeContribution(t *testing.T) {

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",
@@ -36,6 +38,7 @@ go_test(
     ],
     embed = [":go_default_library"],
     deps = [
+        "//beacon-chain/blockchain/kzg:go_default_library",
         "//beacon-chain/blockchain/testing:go_default_library",
         "//beacon-chain/db/filesystem:go_default_library",
         "//beacon-chain/db/testing:go_default_library",
@@ -47,12 +50,16 @@ go_test(
         "//beacon-chain/verification:go_default_library",
         "//config/params:go_default_library",
         "//consensus-types/blocks:go_default_library",
+        "//consensus-types/interfaces:go_default_library",
         "//consensus-types/primitives:go_default_library",
         "//encoding/bytesutil:go_default_library",
         "//proto/prysm/v1alpha1:go_default_library",
         "//testing/assert:go_default_library",
         "//testing/require:go_default_library",
         "//testing/util:go_default_library",
+        "@com_github_consensys_gnark_crypto//ecc/bls12-381/fr:go_default_library",
+        "@com_github_crate_crypto_go_kzg_4844//:go_default_library",
         "@com_github_ethereum_go_ethereum//common/hexutil:go_default_library",
+        "@com_github_sirupsen_logrus//: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"
@@ -40,7 +43,7 @@ func (e BlockIdParseError) Error() string {
 // Blocker is responsible for retrieving blocks.
 type Blocker interface {
 	Block(ctx context.Context, id []byte) (interfaces.ReadOnlySignedBeaconBlock, error)
-	Blobs(ctx context.Context, id string, indices []uint64) ([]*blocks.VerifiedROBlob, *core.RpcError)
+	Blobs(ctx context.Context, id string, indices []int) ([]*blocks.VerifiedROBlob, *core.RpcError)
 }
 
 // BeaconDbBlocker is an implementation of Blocker. It retrieves blocks from the beacon chain database.
@@ -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:
@@ -129,6 +133,137 @@ func (p *BeaconDbBlocker) Block(ctx context.Context, id []byte) (interfaces.Read
 	return blk, nil
 }
 
+// blobsFromStoredBlobs retrieves blobs corresponding to `indices` and `root` from the store.
+// This function expects blobs to be stored directly (aka. no data columns).
+func (p *BeaconDbBlocker) blobsFromStoredBlobs(indices []int, root []byte, commitments [][]byte) ([]*blocks.VerifiedROBlob, *core.RpcError) {
+	sum := p.BlobStorage.Summary(bytesutil.ToBytes32(root))
+
+	if len(indices) == 0 {
+		for index := range commitments {
+			if sum.HasIndex(uint64(index)) {
+				indices = append(indices, index)
+			}
+		}
+	} else {
+		for _, index := range indices {
+			if uint64(index) >= sum.MaxBlobsForEpoch() {
+				return nil, &core.RpcError{
+					Err:    fmt.Errorf("requested index %d is bigger than the maximum possible blob count %d", index, sum.MaxBlobsForEpoch()),
+					Reason: core.BadRequest,
+				}
+			}
+
+			if !sum.HasIndex(uint64(index)) {
+				return nil, &core.RpcError{
+					Err:    fmt.Errorf("requested index %d not found", index),
+					Reason: core.NotFound,
+				}
+			}
+		}
+	}
+
+	blobs := make([]*blocks.VerifiedROBlob, 0, len(indices))
+	for _, index := range indices {
+		vblob, err := p.BlobStorage.Get(bytesutil.ToBytes32(root), uint64(index))
+		if err != nil {
+			return nil, &core.RpcError{
+				Err:    fmt.Errorf("could not retrieve blob for block root %#x at index %d", root, index),
+				Reason: core.Internal,
+			}
+		}
+		blobs = append(blobs, &vblob)
+	}
+
+	return blobs, nil
+}
+
+// blobsFromStoredDataColumns retrieves data columns from the store, reconstruct the whole matrix if needed, convert the matrix to blobs,
+// and then returns blobs corresponding to `indices` and `root` from the store,
+// This function expects data columns to be stored (aka. no blobs).
+// If not enough data columns are available to extract blobs from them (either directly or after reconstruction), an error is returned.
+func (p *BeaconDbBlocker) blobsFromStoredDataColumns(block blocks.ROBlock, indices []int, rootBytes []byte) ([]*blocks.VerifiedROBlob, *core.RpcError) {
+	root := bytesutil.ToBytes32(rootBytes)
+
+	// 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 success, 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,
+		}
+	}
+
+	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
+}
+
+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
+}
+
 // Blobs returns the blobs for a given block id identifier and blob indices. The identifier can be one of:
 //   - "head" (canonical head in node's view)
 //   - "genesis"
@@ -144,7 +279,7 @@ func (p *BeaconDbBlocker) Block(ctx context.Context, id []byte) (interfaces.Read
 //   - block exists, has commitments, inside retention period (greater of protocol- or user-specified) serve then w/ 200 unless we hit an error reading them.
 //     we are technically not supposed to import a block to forkchoice unless we have the blobs, so the nuance here is if we can't find the file and we are inside the protocol-defined retention period, then it's actually a 500.
 //   - block exists, has commitments, outside retention period (greater of protocol- or user-specified) - ie just like block exists, no commitment
-func (p *BeaconDbBlocker) Blobs(ctx context.Context, id string, indices []uint64) ([]*blocks.VerifiedROBlob, *core.RpcError) {
+func (p *BeaconDbBlocker) Blobs(ctx context.Context, id string, indices []int) ([]*blocks.VerifiedROBlob, *core.RpcError) {
 	var rootSlice []byte
 	switch id {
 	case "genesis":
@@ -212,64 +347,55 @@ func (p *BeaconDbBlocker) Blobs(ctx context.Context, id string, indices []uint64
 
 	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 len(commitments) == 0 {
 		return make([]*blocks.VerifiedROBlob, 0), nil
 	}
 
-	sum := p.BlobStorage.Summary(root)
+	// Get the slot of the block.
+	blockSlot := roBlock.Slot()
 
-	if len(indices) == 0 {
-		for i := range commitments {
-			if sum.HasIndex(uint64(i)) {
-				indices = append(indices, uint64(i))
-			}
-		}
-	} else {
-		for _, ix := range indices {
-			if 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(ix) {
-				return nil, &core.RpcError{
-					Err:    fmt.Errorf("requested index %d not found", ix),
-					Reason: core.NotFound,
-				}
-			}
-		}
-	}
+	// Get the first peerDAS epoch.
+	fuluForkEpoch := params.BeaconConfig().FuluForkEpoch
 
-	blobs := make([]*blocks.VerifiedROBlob, len(indices))
-	for i, index := range indices {
-		vblob, err := p.BlobStorage.Get(root, index)
+	// Compute the first peerDAS slot.
+	fuluForkSlot := primitives.Slot(math.MaxUint64)
+	if fuluForkEpoch != primitives.Epoch(math.MaxUint64) {
+		fuluForkSlot, err = slots.EpochStart(fuluForkEpoch)
 		if err != nil {
-			return nil, &core.RpcError{
-				Err:    fmt.Errorf("could not retrieve blob for block root %#x at index %d", rootSlice, index),
-				Reason: core.Internal,
-			}
+			return nil, &core.RpcError{Err: errors.Wrap(err, "could not calculate peerDAS start slot"), Reason: core.Internal}
 		}
-		blobs[i] = &vblob
 	}
 
-	return blobs, nil
+	if blockSlot >= 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, rootSlice)
+	}
+
+	return p.blobsFromStoredBlobs(indices, rootSlice, commitments)
 }

beacon-chain/rpc/lookup/blocker_test.go

@@ -1,7 +1,10 @@
 package lookup
 
 import (
+	"bytes"
 	"context"
+	"crypto/sha256"
+	"encoding/binary"
 	"fmt"
 	"math"
 	"net/http"
@@ -9,6 +12,7 @@ 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/db/filesystem"
 	testDB "github.com/OffchainLabs/prysm/v6/beacon-chain/db/testing"
@@ -17,12 +21,16 @@ import (
 	"github.com/OffchainLabs/prysm/v6/beacon-chain/verification"
 	"github.com/OffchainLabs/prysm/v6/config/params"
 	"github.com/OffchainLabs/prysm/v6/consensus-types/blocks"
+	"github.com/OffchainLabs/prysm/v6/consensus-types/interfaces"
 	"github.com/OffchainLabs/prysm/v6/encoding/bytesutil"
-	ethpbalpha "github.com/OffchainLabs/prysm/v6/proto/prysm/v1alpha1"
+	ethpb "github.com/OffchainLabs/prysm/v6/proto/prysm/v1alpha1"
 	"github.com/OffchainLabs/prysm/v6/testing/assert"
 	"github.com/OffchainLabs/prysm/v6/testing/require"
 	"github.com/OffchainLabs/prysm/v6/testing/util"
+	"github.com/consensys/gnark-crypto/ecc/bls12-381/fr"
+	GoKZG "github.com/crate-crypto/go-kzg-4844"
 	"github.com/ethereum/go-ethereum/common/hexutil"
+	"github.com/sirupsen/logrus"
 )
 
 func TestGetBlock(t *testing.T) {
@@ -51,7 +59,7 @@ func TestGetBlock(t *testing.T) {
 	b4.Block.ParentRoot = bytesutil.PadTo([]byte{8}, 32)
 	util.SaveBlock(t, ctx, beaconDB, b4)
 
-	wsb, err := blocks.NewSignedBeaconBlock(headBlock.Block.(*ethpbalpha.BeaconBlockContainer_Phase0Block).Phase0Block)
+	wsb, err := blocks.NewSignedBeaconBlock(headBlock.Block.(*ethpb.BeaconBlockContainer_Phase0Block).Phase0Block)
 	require.NoError(t, err)
 
 	fetcher := &BeaconDbBlocker{
@@ -60,7 +68,7 @@ func TestGetBlock(t *testing.T) {
 			DB:                  beaconDB,
 			Block:               wsb,
 			Root:                headBlock.BlockRoot,
-			FinalizedCheckPoint: &ethpbalpha.Checkpoint{Root: blkContainers[64].BlockRoot},
+			FinalizedCheckPoint: &ethpb.Checkpoint{Root: blkContainers[64].BlockRoot},
 			CanonicalRoots:      canonicalRoots,
 		},
 	}
@@ -71,13 +79,13 @@ func TestGetBlock(t *testing.T) {
 	tests := []struct {
 		name    string
 		blockID []byte
-		want    *ethpbalpha.SignedBeaconBlock
+		want    *ethpb.SignedBeaconBlock
 		wantErr bool
 	}{
 		{
 			name:    "slot",
 			blockID: []byte("30"),
-			want:    blkContainers[30].Block.(*ethpbalpha.BeaconBlockContainer_Phase0Block).Phase0Block,
+			want:    blkContainers[30].Block.(*ethpb.BeaconBlockContainer_Phase0Block).Phase0Block,
 		},
 		{
 			name:    "bad formatting",
@@ -87,7 +95,7 @@ func TestGetBlock(t *testing.T) {
 		{
 			name:    "canonical",
 			blockID: []byte("30"),
-			want:    blkContainers[30].Block.(*ethpbalpha.BeaconBlockContainer_Phase0Block).Phase0Block,
+			want:    blkContainers[30].Block.(*ethpb.BeaconBlockContainer_Phase0Block).Phase0Block,
 		},
 		{
 			name:    "non canonical",
@@ -97,12 +105,12 @@ func TestGetBlock(t *testing.T) {
 		{
 			name:    "head",
 			blockID: []byte("head"),
-			want:    headBlock.Block.(*ethpbalpha.BeaconBlockContainer_Phase0Block).Phase0Block,
+			want:    headBlock.Block.(*ethpb.BeaconBlockContainer_Phase0Block).Phase0Block,
 		},
 		{
 			name:    "finalized",
 			blockID: []byte("finalized"),
-			want:    blkContainers[64].Block.(*ethpbalpha.BeaconBlockContainer_Phase0Block).Phase0Block,
+			want:    blkContainers[64].Block.(*ethpb.BeaconBlockContainer_Phase0Block).Phase0Block,
 		},
 		{
 			name:    "genesis",
@@ -117,7 +125,7 @@ func TestGetBlock(t *testing.T) {
 		{
 			name:    "root",
 			blockID: blkContainers[20].BlockRoot,
-			want:    blkContainers[20].Block.(*ethpbalpha.BeaconBlockContainer_Phase0Block).Phase0Block,
+			want:    blkContainers[20].Block.(*ethpb.BeaconBlockContainer_Phase0Block).Phase0Block,
 		},
 		{
 			name:    "non-existent root",
@@ -127,7 +135,7 @@ func TestGetBlock(t *testing.T) {
 		{
 			name:    "hex",
 			blockID: []byte(hexutil.Encode(blkContainers[20].BlockRoot)),
-			want:    blkContainers[20].Block.(*ethpbalpha.BeaconBlockContainer_Phase0Block).Phase0Block,
+			want:    blkContainers[20].Block.(*ethpb.BeaconBlockContainer_Phase0Block).Phase0Block,
 		},
 		{
 			name:    "no block",
@@ -149,7 +157,7 @@ func TestGetBlock(t *testing.T) {
 			require.NoError(t, err)
 			pb, err := result.Proto()
 			require.NoError(t, err)
-			pbBlock, ok := pb.(*ethpbalpha.SignedBeaconBlock)
+			pbBlock, ok := pb.(*ethpb.SignedBeaconBlock)
 			require.Equal(t, true, ok)
 			if !reflect.DeepEqual(pbBlock, tt.want) {
 				t.Error("Expected blocks to equal")
@@ -158,6 +166,118 @@ func TestGetBlock(t *testing.T) {
 	}
 }
 
+func deterministicRandomness(seed int64) [32]byte {
+	// Converts an int64 to a byte slice
+	buf := new(bytes.Buffer)
+	err := binary.Write(buf, binary.BigEndian, seed)
+	if err != nil {
+		logrus.WithError(err).Error("Failed to write int64 to bytes buffer")
+		return [32]byte{}
+	}
+	bytes := buf.Bytes()
+
+	return sha256.Sum256(bytes)
+}
+
+// Returns a serialized random field element in big-endian
+func getRandFieldElement(seed int64) [32]byte {
+	bytes := deterministicRandomness(seed)
+	var r fr.Element
+	r.SetBytes(bytes[:])
+
+	return GoKZG.SerializeScalar(r)
+}
+
+// Returns a random blob using the passed seed as entropy
+func getRandBlob(seed int64) kzg.Blob {
+	var blob kzg.Blob
+	for i := 0; i < len(blob); i += 32 {
+		fieldElementBytes := getRandFieldElement(seed + int64(i))
+		copy(blob[i:i+32], fieldElementBytes[:])
+	}
+	return blob
+}
+
+func generateCommitmentAndProof(blob *kzg.Blob) (*kzg.Commitment, *kzg.Proof, error) {
+	commitment, err := kzg.BlobToKZGCommitment(blob)
+	if err != nil {
+		return nil, nil, err
+	}
+	proof, err := kzg.ComputeBlobKZGProof(blob, commitment)
+	if err != nil {
+		return nil, nil, err
+	}
+	return &commitment, &proof, err
+}
+
+func generateRandomBlocSignedBeaconBlockkAndVerifiedRoBlobs(t *testing.T, blobCount int) (interfaces.SignedBeaconBlock, []*blocks.VerifiedROBlob) {
+	// Create a protobuf signed beacon block.
+	signedBeaconBlockPb := util.NewBeaconBlockDeneb()
+
+	// Generate random blobs and their corresponding commitments and proofs.
+	blobs := make([]kzg.Blob, 0, blobCount)
+	blobKzgCommitments := make([]*kzg.Commitment, 0, blobCount)
+	blobKzgProofs := make([]*kzg.Proof, 0, blobCount)
+
+	for blobIndex := range blobCount {
+		// Create a random blob.
+		blob := getRandBlob(int64(blobIndex))
+		blobs = append(blobs, blob)
+
+		// Generate a blobKZGCommitment for the blob.
+		blobKZGCommitment, proof, err := generateCommitmentAndProof(&blob)
+		require.NoError(t, err)
+
+		blobKzgCommitments = append(blobKzgCommitments, blobKZGCommitment)
+		blobKzgProofs = append(blobKzgProofs, proof)
+	}
+
+	// Set the commitments into the block.
+	blobZkgCommitmentsBytes := make([][]byte, 0, blobCount)
+	for _, blobKZGCommitment := range blobKzgCommitments {
+		blobZkgCommitmentsBytes = append(blobZkgCommitmentsBytes, blobKZGCommitment[:])
+	}
+
+	signedBeaconBlockPb.Block.Body.BlobKzgCommitments = blobZkgCommitmentsBytes
+
+	// Generate verified RO blobs.
+	verifiedROBlobs := make([]*blocks.VerifiedROBlob, 0, blobCount)
+
+	// Create a signed beacon block from the protobuf.
+	signedBeaconBlock, err := blocks.NewSignedBeaconBlock(signedBeaconBlockPb)
+	require.NoError(t, err)
+
+	commitmentInclusionProof, err := blocks.MerkleProofKZGCommitments(signedBeaconBlock.Block().Body())
+	require.NoError(t, err)
+
+	for blobIndex := range blobCount {
+		blob := blobs[blobIndex]
+		blobKZGCommitment := blobKzgCommitments[blobIndex]
+		blobKzgProof := blobKzgProofs[blobIndex]
+
+		// Get the signed beacon block header.
+		signedBeaconBlockHeader, err := signedBeaconBlock.Header()
+		require.NoError(t, err)
+
+		blobSidecar := &ethpb.BlobSidecar{
+			Index:                    uint64(blobIndex),
+			Blob:                     blob[:],
+			KzgCommitment:            blobKZGCommitment[:],
+			KzgProof:                 blobKzgProof[:],
+			SignedBlockHeader:        signedBeaconBlockHeader,
+			CommitmentInclusionProof: commitmentInclusionProof,
+		}
+
+		roBlob, err := blocks.NewROBlob(blobSidecar)
+		require.NoError(t, err)
+
+		verifiedROBlob := blocks.NewVerifiedROBlob(roBlob)
+		verifiedROBlobs = append(verifiedROBlobs, &verifiedROBlob)
+	}
+
+	return signedBeaconBlock, verifiedROBlobs
+}
+
 func TestGetBlob(t *testing.T) {
 	params.SetupTestConfigCleanup(t)
 	cfg := params.BeaconConfig().Copy()
@@ -218,7 +338,7 @@ func TestGetBlob(t *testing.T) {
 	})
 	t.Run("finalized", func(t *testing.T) {
 		blocker := &BeaconDbBlocker{
-			ChainInfoFetcher: &mockChain.ChainService{FinalizedCheckPoint: &ethpbalpha.Checkpoint{Root: blockRoot[:]}},
+			ChainInfoFetcher: &mockChain.ChainService{FinalizedCheckPoint: &ethpb.Checkpoint{Root: blockRoot[:]}},
 			GenesisTimeFetcher: &testutil.MockGenesisTimeFetcher{
 				Genesis: time.Now(),
 			},
@@ -232,7 +352,7 @@ func TestGetBlob(t *testing.T) {
 	})
 	t.Run("justified", func(t *testing.T) {
 		blocker := &BeaconDbBlocker{
-			ChainInfoFetcher: &mockChain.ChainService{CurrentJustifiedCheckPoint: &ethpbalpha.Checkpoint{Root: blockRoot[:]}},
+			ChainInfoFetcher: &mockChain.ChainService{CurrentJustifiedCheckPoint: &ethpb.Checkpoint{Root: blockRoot[:]}},
 			GenesisTimeFetcher: &testutil.MockGenesisTimeFetcher{
 				Genesis: time.Now(),
 			},
@@ -270,14 +390,14 @@ func TestGetBlob(t *testing.T) {
 	})
 	t.Run("one blob only", func(t *testing.T) {
 		blocker := &BeaconDbBlocker{
-			ChainInfoFetcher: &mockChain.ChainService{FinalizedCheckPoint: &ethpbalpha.Checkpoint{Root: blockRoot[:]}},
+			ChainInfoFetcher: &mockChain.ChainService{FinalizedCheckPoint: &ethpb.Checkpoint{Root: blockRoot[:]}},
 			GenesisTimeFetcher: &testutil.MockGenesisTimeFetcher{
 				Genesis: time.Now(),
 			},
 			BeaconDB:    db,
 			BlobStorage: bs,
 		}
-		verifiedBlobs, rpcErr := blocker.Blobs(ctx, "123", []uint64{2})
+		verifiedBlobs, rpcErr := blocker.Blobs(ctx, "123", []int{2})
 		assert.Equal(t, rpcErr == nil, true)
 		require.Equal(t, 1, len(verifiedBlobs))
 		sidecar := verifiedBlobs[0].BlobSidecar
@@ -289,7 +409,7 @@ func TestGetBlob(t *testing.T) {
 	})
 	t.Run("no blobs returns an empty array", func(t *testing.T) {
 		blocker := &BeaconDbBlocker{
-			ChainInfoFetcher: &mockChain.ChainService{FinalizedCheckPoint: &ethpbalpha.Checkpoint{Root: blockRoot[:]}},
+			ChainInfoFetcher: &mockChain.ChainService{FinalizedCheckPoint: &ethpb.Checkpoint{Root: blockRoot[:]}},
 			GenesisTimeFetcher: &testutil.MockGenesisTimeFetcher{
 				Genesis: time.Now(),
 			},
@@ -302,28 +422,28 @@ func TestGetBlob(t *testing.T) {
 	})
 	t.Run("no blob at index", func(t *testing.T) {
 		blocker := &BeaconDbBlocker{
-			ChainInfoFetcher: &mockChain.ChainService{FinalizedCheckPoint: &ethpbalpha.Checkpoint{Root: blockRoot[:]}},
+			ChainInfoFetcher: &mockChain.ChainService{FinalizedCheckPoint: &ethpb.Checkpoint{Root: blockRoot[:]}},
 			GenesisTimeFetcher: &testutil.MockGenesisTimeFetcher{
 				Genesis: time.Now(),
 			},
 			BeaconDB:    db,
 			BlobStorage: bs,
 		}
-		noBlobIndex := uint64(len(blobs)) + 1
-		_, rpcErr := blocker.Blobs(ctx, "123", []uint64{0, noBlobIndex})
+		noBlobIndex := len(blobs) + 1
+		_, rpcErr := blocker.Blobs(ctx, "123", []int{0, noBlobIndex})
 		require.NotNil(t, rpcErr)
 		assert.Equal(t, core.ErrorReason(core.NotFound), rpcErr.Reason)
 	})
 	t.Run("index too big", func(t *testing.T) {
 		blocker := &BeaconDbBlocker{
-			ChainInfoFetcher: &mockChain.ChainService{FinalizedCheckPoint: &ethpbalpha.Checkpoint{Root: blockRoot[:]}},
+			ChainInfoFetcher: &mockChain.ChainService{FinalizedCheckPoint: &ethpb.Checkpoint{Root: blockRoot[:]}},
 			GenesisTimeFetcher: &testutil.MockGenesisTimeFetcher{
 				Genesis: time.Now(),
 			},
 			BeaconDB:    db,
 			BlobStorage: bs,
 		}
-		_, rpcErr := blocker.Blobs(ctx, "123", []uint64{0, math.MaxUint})
+		_, rpcErr := blocker.Blobs(ctx, "123", []int{0, math.MaxInt})
 		require.NotNil(t, rpcErr)
 		assert.Equal(t, core.ErrorReason(core.BadRequest), rpcErr.Reason)
 	})

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

@@ -109,6 +109,8 @@ func (ds *Server) getPeer(pid peer.ID) (*ethpb.DebugPeerResponse, error) {
 			peerInfo.MetadataV0 = metadata.MetadataObjV0()
 		case metadata.MetadataObjV1() != nil:
 			peerInfo.MetadataV1 = metadata.MetadataObjV1()
+		case metadata.MetadataObjV2() != nil:
+			peerInfo.MetadataV2 = metadata.MetadataObjV2()
 		}
 	}
 	addresses := peerStore.Addrs(pid)

beacon-chain/rpc/prysm/v1alpha1/validator/BUILD.bazel

@@ -1,3 +1,5 @@
+# gazelle:ignore
+
 load("@prysm//tools/go:def.bzl", "go_library", "go_test")
 
 go_library(
@@ -8,6 +10,7 @@ go_library(
         "blocks.go",
         "construct_generic_block.go",
         "duties.go",
+        "duties_v2.go",
         "exit.go",
         "log.go",
         "proposer.go",
@@ -36,6 +39,7 @@ go_library(
         "//api/client/builder:go_default_library",
         "//async/event:go_default_library",
         "//beacon-chain/blockchain:go_default_library",
+        "//beacon-chain/blockchain/kzg:go_default_library",
         "//beacon-chain/builder:go_default_library",
         "//beacon-chain/cache:go_default_library",
         "//beacon-chain/cache/depositsnapshot:go_default_library",
@@ -46,6 +50,7 @@ go_library(
         "//beacon-chain/core/feed/operation: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/signing:go_default_library",
         "//beacon-chain/core/time:go_default_library",
         "//beacon-chain/core/transition:go_default_library",
@@ -179,7 +184,6 @@ common_deps = [
     "@org_golang_google_protobuf//types/known/emptypb:go_default_library",
 ]
 
-# gazelle:ignore
 go_test(
     name = "go_default_test",
     timeout = "moderate",
@@ -189,6 +193,7 @@ go_test(
         "blocks_test.go",
         "construct_generic_block_test.go",
         "duties_test.go",
+        "duties_v2_test.go",
         "exit_test.go",
         "proposer_altair_test.go",
         "proposer_attestations_electra_test.go",

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()
@@ -34,12 +39,21 @@ func (vs *Server) constructGenericBeaconBlock(sBlk interfaces.SignedBeaconBlock,
 		return vs.constructBellatrixBlock(blockProto, isBlinded, bidStr), nil
 	case version.Capella:
 		return vs.constructCapellaBlock(blockProto, isBlinded, bidStr), nil
-	case version.Deneb:
-		return vs.constructDenebBlock(blockProto, isBlinded, bidStr, blobsBundle), nil
-	case version.Electra:
-		return vs.constructElectraBlock(blockProto, isBlinded, bidStr, blobsBundle), nil
+	case version.Deneb, version.Electra:
+		bundle, ok := blobsBundler.(*enginev1.BlobsBundle)
+		if blobsBundler != nil && !ok {
+			return nil, fmt.Errorf("expected *BlobsBundler, got %T", blobsBundler)
+		}
+		if sBlk.Version() == version.Deneb {
+			return vs.constructDenebBlock(blockProto, isBlinded, bidStr, bundle), nil
+		}
+		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 +106,7 @@ 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/construct_generic_block_test.go

@@ -29,12 +29,19 @@ func TestConstructGenericBeaconBlock(t *testing.T) {
 		require.NoError(t, err)
 		r1, err := eb.Block.HashTreeRoot()
 		require.NoError(t, err)
-		result, err := vs.constructGenericBeaconBlock(b, nil, primitives.ZeroWei())
+		bundle := &enginev1.BlobsBundleV2{
+			KzgCommitments: [][]byte{{1, 2, 3}},
+			Proofs:         [][]byte{{4, 5, 6}},
+			Blobs:          [][]byte{{7, 8, 9}},
+		}
+		result, err := vs.constructGenericBeaconBlock(b, bundle, primitives.ZeroWei())
 		require.NoError(t, err)
 		r2, err := result.GetFulu().Block.HashTreeRoot()
 		require.NoError(t, err)
 		require.Equal(t, r1, r2)
 		require.Equal(t, result.IsBlinded, false)
+		require.DeepEqual(t, bundle.Blobs, result.GetFulu().GetBlobs())
+		require.DeepEqual(t, bundle.Proofs, result.GetFulu().GetKzgProofs())
 	})
 
 	// Test for Electra version

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

@@ -0,0 +1,268 @@
+package validator
+
+import (
+	"context"
+
+	"github.com/OffchainLabs/prysm/v6/beacon-chain/core/helpers"
+	coreTime "github.com/OffchainLabs/prysm/v6/beacon-chain/core/time"
+	"github.com/OffchainLabs/prysm/v6/beacon-chain/core/transition"
+	"github.com/OffchainLabs/prysm/v6/beacon-chain/rpc/core"
+	"github.com/OffchainLabs/prysm/v6/beacon-chain/state"
+	"github.com/OffchainLabs/prysm/v6/consensus-types/primitives"
+	"github.com/OffchainLabs/prysm/v6/encoding/bytesutil"
+	"github.com/OffchainLabs/prysm/v6/monitoring/tracing/trace"
+	ethpb "github.com/OffchainLabs/prysm/v6/proto/prysm/v1alpha1"
+	"github.com/OffchainLabs/prysm/v6/time/slots"
+	"google.golang.org/grpc/codes"
+	"google.golang.org/grpc/status"
+)
+
+// GetDutiesV2 returns the duties assigned to a list of validators specified
+// in the request object.
+//
+// Deprecated: The gRPC API will remain the default and fully supported through v8 (expected in 2026) but will be eventually removed in favor of REST API.
+func (vs *Server) GetDutiesV2(ctx context.Context, req *ethpb.DutiesRequest) (*ethpb.DutiesV2Response, error) {
+	if vs.SyncChecker.Syncing() {
+		return nil, status.Error(codes.Unavailable, "Syncing to latest head, not ready to respond")
+	}
+	return vs.dutiesv2(ctx, req)
+}
+
+// Compute the validator duties from the head state's corresponding epoch
+// for validators public key / indices requested.
+func (vs *Server) dutiesv2(ctx context.Context, req *ethpb.DutiesRequest) (*ethpb.DutiesV2Response, error) {
+	currentEpoch := slots.ToEpoch(vs.TimeFetcher.CurrentSlot())
+	if req.Epoch > currentEpoch+1 {
+		return nil, status.Errorf(codes.Unavailable, "Request epoch %d can not be greater than next epoch %d", req.Epoch, currentEpoch+1)
+	}
+
+	// Load head state
+	s, err := vs.HeadFetcher.HeadState(ctx)
+	if err != nil {
+		return nil, status.Errorf(codes.Internal, "Could not get head state: %v", err)
+	}
+
+	// Advance to start of requested epoch if necessary
+	s, err = vs.stateForEpoch(ctx, s, req.Epoch)
+	if err != nil {
+		return nil, err
+	}
+
+	// Build duties for each validator
+	ctx, span := trace.StartSpan(ctx, "dutiesv2.BuildResponse")
+	span.SetAttributes(trace.Int64Attribute("num_pubkeys", int64(len(req.PublicKeys))))
+	defer span.End()
+
+	// Load committee and proposer metadata
+	meta, err := loadDutiesMetadata(ctx, s, req.Epoch)
+	if err != nil {
+		return nil, err
+	}
+
+	validatorAssignments := make([]*ethpb.DutiesV2Response_Duty, 0, len(req.PublicKeys))
+	nextValidatorAssignments := make([]*ethpb.DutiesV2Response_Duty, 0, len(req.PublicKeys))
+
+	// start loop for assignments for current and next epochs
+	for _, pubKey := range req.PublicKeys {
+		if ctx.Err() != nil {
+			return nil, status.Errorf(codes.Aborted, "Could not continue fetching assignments: %v", ctx.Err())
+		}
+
+		idx, ok := s.ValidatorIndexByPubkey(bytesutil.ToBytes48(pubKey))
+		if !ok {
+			// Unknown validator: still append placeholder duty with UNKNOWN_STATUS
+			validatorAssignments = append(validatorAssignments, &ethpb.DutiesV2Response_Duty{
+				PublicKey: pubKey,
+				Status:    ethpb.ValidatorStatus_UNKNOWN_STATUS,
+			})
+			nextValidatorAssignments = append(nextValidatorAssignments, &ethpb.DutiesV2Response_Duty{
+				PublicKey: pubKey,
+				Status:    ethpb.ValidatorStatus_UNKNOWN_STATUS,
+			})
+			continue
+		}
+
+		meta.current.liteAssignment = helpers.AssignmentForValidator(meta.current.committeesBySlot, meta.current.startSlot, idx)
+		meta.next.liteAssignment = helpers.AssignmentForValidator(meta.next.committeesBySlot, meta.next.startSlot, idx)
+
+		assignment, nextAssignment, err := vs.buildValidatorDuty(pubKey, idx, s, req.Epoch, meta)
+		if err != nil {
+			return nil, err
+		}
+		validatorAssignments = append(validatorAssignments, assignment)
+		nextValidatorAssignments = append(nextValidatorAssignments, nextAssignment)
+	}
+
+	// Dependent roots for fork choice
+	currDependentRoot, err := vs.ForkchoiceFetcher.DependentRoot(currentEpoch)
+	if err != nil {
+		return nil, status.Errorf(codes.Internal, "Could not get dependent root: %v", err)
+	}
+	prevDependentRoot := currDependentRoot
+	if currDependentRoot != [32]byte{} && currentEpoch > 0 {
+		prevDependentRoot, err = vs.ForkchoiceFetcher.DependentRoot(currentEpoch - 1)
+		if err != nil {
+			return nil, status.Errorf(codes.Internal, "Could not get previous dependent root: %v", err)
+		}
+	}
+
+	return &ethpb.DutiesV2Response{
+		PreviousDutyDependentRoot: prevDependentRoot[:],
+		CurrentDutyDependentRoot:  currDependentRoot[:],
+		CurrentEpochDuties:        validatorAssignments,
+		NextEpochDuties:           nextValidatorAssignments,
+	}, nil
+}
+
+// stateForEpoch returns a state advanced (with empty slot transitions) to the
+// start slot of the requested epoch.
+func (vs *Server) stateForEpoch(ctx context.Context, s state.BeaconState, reqEpoch primitives.Epoch) (state.BeaconState, error) {
+	epochStartSlot, err := slots.EpochStart(reqEpoch)
+	if err != nil {
+		return nil, err
+	}
+	if s.Slot() >= epochStartSlot {
+		return s, nil
+	}
+	headRoot, err := vs.HeadFetcher.HeadRoot(ctx)
+	if err != nil {
+		return nil, status.Errorf(codes.Internal, "Could not retrieve head root: %v", err)
+	}
+	s, err = transition.ProcessSlotsUsingNextSlotCache(ctx, s, headRoot, epochStartSlot)
+	if err != nil {
+		return nil, status.Errorf(codes.Internal, "Could not process slots up to %d: %v", epochStartSlot, err)
+	}
+	return s, nil
+}
+
+// dutiesMetadata bundles together related data needed for duty
+// construction.
+type dutiesMetadata struct {
+	current *metadata
+	next    *metadata
+}
+
+type metadata struct {
+	committeesAtSlot uint64
+	proposalSlots    map[primitives.ValidatorIndex][]primitives.Slot
+	startSlot        primitives.Slot
+	committeesBySlot [][][]primitives.ValidatorIndex
+	liteAssignment   *helpers.LiteAssignment
+}
+
+func loadDutiesMetadata(ctx context.Context, s state.BeaconState, reqEpoch primitives.Epoch) (*dutiesMetadata, error) {
+	meta := &dutiesMetadata{}
+	var err error
+	meta.current, err = loadMetadata(ctx, s, reqEpoch)
+	if err != nil {
+		return nil, err
+	}
+	// note: we only set the proposer slots for the current assignment and not the next epoch assignment
+	meta.current.proposalSlots, err = helpers.ProposerAssignments(ctx, s, reqEpoch)
+	if err != nil {
+		return nil, status.Errorf(codes.Internal, "Could not compute proposer slots: %v", err)
+	}
+
+	meta.next, err = loadMetadata(ctx, s, reqEpoch+1)
+	if err != nil {
+		return nil, err
+	}
+	return meta, nil
+}
+
+func loadMetadata(ctx context.Context, s state.BeaconState, reqEpoch primitives.Epoch) (*metadata, error) {
+	meta := &metadata{}
+
+	if err := helpers.VerifyAssignmentEpoch(reqEpoch, s); err != nil {
+		return nil, err
+	}
+
+	activeValidatorCount, err := helpers.ActiveValidatorCount(ctx, s, reqEpoch)
+	if err != nil {
+		return nil, status.Errorf(codes.Internal, "Could not get active validator count: %v", err)
+	}
+	meta.committeesAtSlot = helpers.SlotCommitteeCount(activeValidatorCount)
+
+	meta.startSlot, err = slots.EpochStart(reqEpoch)
+	if err != nil {
+		return nil, err
+	}
+
+	meta.committeesBySlot, err = helpers.PrecomputeCommittees(ctx, s, meta.startSlot)
+	if err != nil {
+		return nil, err
+	}
+
+	return meta, nil
+}
+
+// buildValidatorDuty builds both current‑epoch and next‑epoch V2 duty objects
+// for a single validator index.
+func (vs *Server) buildValidatorDuty(
+	pubKey []byte,
+	idx primitives.ValidatorIndex,
+	s state.BeaconState,
+	reqEpoch primitives.Epoch,
+	meta *dutiesMetadata,
+) (*ethpb.DutiesV2Response_Duty, *ethpb.DutiesV2Response_Duty, error) {
+	assignment := &ethpb.DutiesV2Response_Duty{PublicKey: pubKey}
+	nextAssignment := &ethpb.DutiesV2Response_Duty{PublicKey: pubKey}
+
+	statusEnum := assignmentStatus(s, idx)
+	assignment.ValidatorIndex = idx
+	assignment.Status = statusEnum
+	assignment.CommitteesAtSlot = meta.current.committeesAtSlot
+	assignment.ProposerSlots = meta.current.proposalSlots[idx]
+	populateCommitteeFields(assignment, meta.current.liteAssignment)
+
+	nextAssignment.ValidatorIndex = idx
+	nextAssignment.Status = statusEnum
+	nextAssignment.CommitteesAtSlot = meta.next.committeesAtSlot
+	populateCommitteeFields(nextAssignment, meta.next.liteAssignment)
+
+	// Sync committee flags
+	if coreTime.HigherEqualThanAltairVersionAndEpoch(s, reqEpoch) {
+		inSync, err := helpers.IsCurrentPeriodSyncCommittee(s, idx)
+		if err != nil {
+			return nil, nil, status.Errorf(codes.Internal, "Could not determine current epoch sync committee: %v", err)
+		}
+		assignment.IsSyncCommittee = inSync
+		nextAssignment.IsSyncCommittee = inSync
+		if inSync {
+			if err := core.RegisterSyncSubnetCurrentPeriodProto(s, reqEpoch, pubKey, statusEnum); err != nil {
+				return nil, nil, status.Errorf(codes.Internal, "Could not register sync subnet current period: %v", err)
+			}
+		}
+
+		// Next epoch sync committee duty is assigned with next period sync committee only during
+		// sync period epoch boundary (ie. EPOCHS_PER_SYNC_COMMITTEE_PERIOD - 1). Else wise
+		// next epoch sync committee duty is the same as current epoch.
+		nextEpoch := reqEpoch + 1
+		currentEpoch := coreTime.CurrentEpoch(s)
+		n := slots.SyncCommitteePeriod(nextEpoch)
+		c := slots.SyncCommitteePeriod(currentEpoch)
+		if n > c {
+			nextInSync, err := helpers.IsNextPeriodSyncCommittee(s, idx)
+			if err != nil {
+				return nil, nil, status.Errorf(codes.Internal, "Could not determine next epoch sync committee: %v", err)
+			}
+			nextAssignment.IsSyncCommittee = nextInSync
+			if nextInSync {
+				go func() {
+					if err := core.RegisterSyncSubnetNextPeriodProto(s, reqEpoch, pubKey, statusEnum); err != nil {
+						log.WithError(err).Warn("Could not register sync subnet next period")
+					}
+				}()
+			}
+		}
+	}
+
+	return assignment, nextAssignment, nil
+}
+
+func populateCommitteeFields(duty *ethpb.DutiesV2Response_Duty, la *helpers.LiteAssignment) {
+	duty.CommitteeLength = la.CommitteeLength
+	duty.CommitteeIndex = la.CommitteeIndex
+	duty.ValidatorCommitteeIndex = la.ValidatorCommitteeIndex
+	duty.AttesterSlot = la.AttesterSlot
+}

beacon-chain/rpc/prysm/v1alpha1/validator/duties_v2_test.go

@@ -0,0 +1,562 @@
+package validator
+
+import (
+	"context"
+	"testing"
+	"time"
+
+	mockChain "github.com/OffchainLabs/prysm/v6/beacon-chain/blockchain/testing"
+	"github.com/OffchainLabs/prysm/v6/beacon-chain/cache"
+	"github.com/OffchainLabs/prysm/v6/beacon-chain/cache/depositsnapshot"
+	"github.com/OffchainLabs/prysm/v6/beacon-chain/core/altair"
+	"github.com/OffchainLabs/prysm/v6/beacon-chain/core/execution"
+	"github.com/OffchainLabs/prysm/v6/beacon-chain/core/helpers"
+	"github.com/OffchainLabs/prysm/v6/beacon-chain/core/transition"
+	mockExecution "github.com/OffchainLabs/prysm/v6/beacon-chain/execution/testing"
+	mockSync "github.com/OffchainLabs/prysm/v6/beacon-chain/sync/initial-sync/testing"
+	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/encoding/bytesutil"
+	ethpb "github.com/OffchainLabs/prysm/v6/proto/prysm/v1alpha1"
+	"github.com/OffchainLabs/prysm/v6/testing/assert"
+	"github.com/OffchainLabs/prysm/v6/testing/require"
+	"github.com/OffchainLabs/prysm/v6/testing/util"
+	"github.com/OffchainLabs/prysm/v6/time/slots"
+)
+
+func TestGetDutiesV2_OK(t *testing.T) {
+	genesis := util.NewBeaconBlock()
+	depChainStart := params.BeaconConfig().MinGenesisActiveValidatorCount
+	deposits, _, err := util.DeterministicDepositsAndKeys(depChainStart)
+	require.NoError(t, err)
+	eth1Data, err := util.DeterministicEth1Data(len(deposits))
+	require.NoError(t, err)
+	bs, err := transition.GenesisBeaconState(context.Background(), deposits, 0, eth1Data)
+	require.NoError(t, err, "Could not setup genesis bs")
+	genesisRoot, err := genesis.Block.HashTreeRoot()
+	require.NoError(t, err, "Could not get signing root")
+
+	pubKeys := make([][]byte, len(deposits))
+	indices := make([]uint64, len(deposits))
+	for i := 0; i < len(deposits); i++ {
+		pubKeys[i] = deposits[i].Data.PublicKey
+		indices[i] = uint64(i)
+	}
+
+	chain := &mockChain.ChainService{
+		State: bs, Root: genesisRoot[:], Genesis: time.Now(),
+	}
+	vs := &Server{
+		HeadFetcher:       chain,
+		TimeFetcher:       chain,
+		ForkchoiceFetcher: chain,
+		SyncChecker:       &mockSync.Sync{IsSyncing: false},
+		PayloadIDCache:    cache.NewPayloadIDCache(),
+	}
+
+	// Test the first validator in registry.
+	req := &ethpb.DutiesRequest{
+		PublicKeys: [][]byte{deposits[0].Data.PublicKey},
+	}
+	res, err := vs.GetDutiesV2(context.Background(), req)
+	require.NoError(t, err, "Could not call epoch committee assignment")
+	if res.CurrentEpochDuties[0].AttesterSlot > bs.Slot()+params.BeaconConfig().SlotsPerEpoch {
+		t.Errorf("Assigned slot %d can't be higher than %d",
+			res.CurrentEpochDuties[0].AttesterSlot, bs.Slot()+params.BeaconConfig().SlotsPerEpoch)
+	}
+
+	// Test the last validator in registry.
+	lastValidatorIndex := depChainStart - 1
+	req = &ethpb.DutiesRequest{
+		PublicKeys: [][]byte{deposits[lastValidatorIndex].Data.PublicKey},
+	}
+	res, err = vs.GetDutiesV2(context.Background(), req)
+	require.NoError(t, err, "Could not call epoch committee assignment")
+	if res.CurrentEpochDuties[0].AttesterSlot > bs.Slot()+params.BeaconConfig().SlotsPerEpoch {
+		t.Errorf("Assigned slot %d can't be higher than %d",
+			res.CurrentEpochDuties[0].AttesterSlot, bs.Slot()+params.BeaconConfig().SlotsPerEpoch)
+	}
+
+	// We request for duties for all validators.
+	req = &ethpb.DutiesRequest{
+		PublicKeys: pubKeys,
+		Epoch:      0,
+	}
+	res, err = vs.GetDutiesV2(context.Background(), req)
+	require.NoError(t, err, "Could not call epoch committee assignment")
+	for i := 0; i < len(res.CurrentEpochDuties); i++ {
+		assert.Equal(t, primitives.ValidatorIndex(i), res.CurrentEpochDuties[i].ValidatorIndex)
+	}
+}
+
+func TestGetAltairDutiesV2_SyncCommitteeOK(t *testing.T) {
+	params.SetupTestConfigCleanup(t)
+	cfg := params.BeaconConfig().Copy()
+	cfg.AltairForkEpoch = primitives.Epoch(0)
+	params.OverrideBeaconConfig(cfg)
+
+	genesis := util.NewBeaconBlock()
+	deposits, _, err := util.DeterministicDepositsAndKeys(params.BeaconConfig().SyncCommitteeSize)
+	require.NoError(t, err)
+	eth1Data, err := util.DeterministicEth1Data(len(deposits))
+	require.NoError(t, err)
+	bs, err := util.GenesisBeaconState(context.Background(), deposits, 0, eth1Data)
+	require.NoError(t, err, "Could not setup genesis bs")
+	h := &ethpb.BeaconBlockHeader{
+		StateRoot:  bytesutil.PadTo([]byte{'a'}, fieldparams.RootLength),
+		ParentRoot: bytesutil.PadTo([]byte{'b'}, fieldparams.RootLength),
+		BodyRoot:   bytesutil.PadTo([]byte{'c'}, fieldparams.RootLength),
+	}
+	require.NoError(t, bs.SetLatestBlockHeader(h))
+	genesisRoot, err := genesis.Block.HashTreeRoot()
+	require.NoError(t, err, "Could not get signing root")
+
+	syncCommittee, err := altair.NextSyncCommittee(context.Background(), bs)
+	require.NoError(t, err)
+	require.NoError(t, bs.SetCurrentSyncCommittee(syncCommittee))
+	pubKeys := make([][]byte, len(deposits))
+	indices := make([]uint64, len(deposits))
+	for i := 0; i < len(deposits); i++ {
+		pubKeys[i] = deposits[i].Data.PublicKey
+		indices[i] = uint64(i)
+	}
+	require.NoError(t, bs.SetSlot(params.BeaconConfig().SlotsPerEpoch*primitives.Slot(params.BeaconConfig().EpochsPerSyncCommitteePeriod)-1))
+	require.NoError(t, helpers.UpdateSyncCommitteeCache(bs))
+
+	pubkeysAs48ByteType := make([][fieldparams.BLSPubkeyLength]byte, len(pubKeys))
+	for i, pk := range pubKeys {
+		pubkeysAs48ByteType[i] = bytesutil.ToBytes48(pk)
+	}
+
+	slot := uint64(params.BeaconConfig().SlotsPerEpoch) * uint64(params.BeaconConfig().EpochsPerSyncCommitteePeriod) * params.BeaconConfig().SecondsPerSlot
+	chain := &mockChain.ChainService{
+		State: bs, Root: genesisRoot[:], Genesis: time.Now().Add(time.Duration(-1*int64(slot-1)) * time.Second),
+	}
+	vs := &Server{
+		HeadFetcher:       chain,
+		TimeFetcher:       chain,
+		ForkchoiceFetcher: chain,
+		Eth1InfoFetcher:   &mockExecution.Chain{},
+		SyncChecker:       &mockSync.Sync{IsSyncing: false},
+		PayloadIDCache:    cache.NewPayloadIDCache(),
+	}
+
+	// Test the first validator in registry.
+	req := &ethpb.DutiesRequest{
+		PublicKeys: [][]byte{deposits[0].Data.PublicKey},
+	}
+	res, err := vs.GetDutiesV2(context.Background(), req)
+	require.NoError(t, err, "Could not call epoch committee assignment")
+	if res.CurrentEpochDuties[0].AttesterSlot > bs.Slot()+params.BeaconConfig().SlotsPerEpoch {
+		t.Errorf("Assigned slot %d can't be higher than %d",
+			res.CurrentEpochDuties[0].AttesterSlot, bs.Slot()+params.BeaconConfig().SlotsPerEpoch)
+	}
+
+	// Test the last validator in registry.
+	lastValidatorIndex := params.BeaconConfig().SyncCommitteeSize - 1
+	req = &ethpb.DutiesRequest{
+		PublicKeys: [][]byte{deposits[lastValidatorIndex].Data.PublicKey},
+	}
+	res, err = vs.GetDutiesV2(context.Background(), req)
+	require.NoError(t, err, "Could not call epoch committee assignment")
+	if res.CurrentEpochDuties[0].AttesterSlot > bs.Slot()+params.BeaconConfig().SlotsPerEpoch {
+		t.Errorf("Assigned slot %d can't be higher than %d",
+			res.CurrentEpochDuties[0].AttesterSlot, bs.Slot()+params.BeaconConfig().SlotsPerEpoch)
+	}
+
+	// We request for duties for all validators.
+	req = &ethpb.DutiesRequest{
+		PublicKeys: pubKeys,
+		Epoch:      0,
+	}
+	res, err = vs.GetDutiesV2(context.Background(), req)
+	require.NoError(t, err, "Could not call epoch committee assignment")
+	for i := 0; i < len(res.CurrentEpochDuties); i++ {
+		require.Equal(t, primitives.ValidatorIndex(i), res.CurrentEpochDuties[i].ValidatorIndex)
+	}
+	for i := 0; i < len(res.CurrentEpochDuties); i++ {
+		require.Equal(t, true, res.CurrentEpochDuties[i].IsSyncCommittee)
+		// Current epoch and next epoch duties should be equal before the sync period epoch boundary.
+		require.Equal(t, res.CurrentEpochDuties[i].IsSyncCommittee, res.NextEpochDuties[i].IsSyncCommittee)
+	}
+
+	// Current epoch and next epoch duties should not be equal at the sync period epoch boundary.
+	req = &ethpb.DutiesRequest{
+		PublicKeys: pubKeys,
+		Epoch:      params.BeaconConfig().EpochsPerSyncCommitteePeriod - 1,
+	}
+	res, err = vs.GetDutiesV2(context.Background(), req)
+	require.NoError(t, err, "Could not call epoch committee assignment")
+	for i := 0; i < len(res.CurrentEpochDuties); i++ {
+		require.NotEqual(t, res.CurrentEpochDuties[i].IsSyncCommittee, res.NextEpochDuties[i].IsSyncCommittee)
+	}
+}
+
+func TestGetBellatrixDutiesV2_SyncCommitteeOK(t *testing.T) {
+	params.SetupTestConfigCleanup(t)
+	cfg := params.BeaconConfig().Copy()
+	cfg.AltairForkEpoch = primitives.Epoch(0)
+	cfg.BellatrixForkEpoch = primitives.Epoch(1)
+	params.OverrideBeaconConfig(cfg)
+
+	genesis := util.NewBeaconBlock()
+	deposits, _, err := util.DeterministicDepositsAndKeys(params.BeaconConfig().SyncCommitteeSize)
+	require.NoError(t, err)
+	eth1Data, err := util.DeterministicEth1Data(len(deposits))
+	require.NoError(t, err)
+	bs, err := util.GenesisBeaconState(context.Background(), deposits, 0, eth1Data)
+	h := &ethpb.BeaconBlockHeader{
+		StateRoot:  bytesutil.PadTo([]byte{'a'}, fieldparams.RootLength),
+		ParentRoot: bytesutil.PadTo([]byte{'b'}, fieldparams.RootLength),
+		BodyRoot:   bytesutil.PadTo([]byte{'c'}, fieldparams.RootLength),
+	}
+	require.NoError(t, bs.SetLatestBlockHeader(h))
+	require.NoError(t, err, "Could not setup genesis bs")
+	genesisRoot, err := genesis.Block.HashTreeRoot()
+	require.NoError(t, err, "Could not get signing root")
+
+	syncCommittee, err := altair.NextSyncCommittee(context.Background(), bs)
+	require.NoError(t, err)
+	require.NoError(t, bs.SetCurrentSyncCommittee(syncCommittee))
+	pubKeys := make([][]byte, len(deposits))
+	indices := make([]uint64, len(deposits))
+	for i := 0; i < len(deposits); i++ {
+		pubKeys[i] = deposits[i].Data.PublicKey
+		indices[i] = uint64(i)
+	}
+	require.NoError(t, bs.SetSlot(params.BeaconConfig().SlotsPerEpoch*primitives.Slot(params.BeaconConfig().EpochsPerSyncCommitteePeriod)-1))
+	require.NoError(t, helpers.UpdateSyncCommitteeCache(bs))
+
+	bs, err = execution.UpgradeToBellatrix(bs)
+	require.NoError(t, err)
+
+	pubkeysAs48ByteType := make([][fieldparams.BLSPubkeyLength]byte, len(pubKeys))
+	for i, pk := range pubKeys {
+		pubkeysAs48ByteType[i] = bytesutil.ToBytes48(pk)
+	}
+
+	slot := uint64(params.BeaconConfig().SlotsPerEpoch) * uint64(params.BeaconConfig().EpochsPerSyncCommitteePeriod) * params.BeaconConfig().SecondsPerSlot
+	chain := &mockChain.ChainService{
+		State: bs, Root: genesisRoot[:], Genesis: time.Now().Add(time.Duration(-1*int64(slot-1)) * time.Second),
+	}
+	vs := &Server{
+		HeadFetcher:       chain,
+		TimeFetcher:       chain,
+		ForkchoiceFetcher: chain,
+		Eth1InfoFetcher:   &mockExecution.Chain{},
+		SyncChecker:       &mockSync.Sync{IsSyncing: false},
+		PayloadIDCache:    cache.NewPayloadIDCache(),
+	}
+
+	// Test the first validator in registry.
+	req := &ethpb.DutiesRequest{
+		PublicKeys: [][]byte{deposits[0].Data.PublicKey},
+	}
+	res, err := vs.GetDutiesV2(context.Background(), req)
+	require.NoError(t, err, "Could not call epoch committee assignment")
+	if res.CurrentEpochDuties[0].AttesterSlot > bs.Slot()+params.BeaconConfig().SlotsPerEpoch {
+		t.Errorf("Assigned slot %d can't be higher than %d",
+			res.CurrentEpochDuties[0].AttesterSlot, bs.Slot()+params.BeaconConfig().SlotsPerEpoch)
+	}
+
+	// Test the last validator in registry.
+	lastValidatorIndex := params.BeaconConfig().SyncCommitteeSize - 1
+	req = &ethpb.DutiesRequest{
+		PublicKeys: [][]byte{deposits[lastValidatorIndex].Data.PublicKey},
+	}
+	res, err = vs.GetDutiesV2(context.Background(), req)
+	require.NoError(t, err, "Could not call epoch committee assignment")
+	if res.CurrentEpochDuties[0].AttesterSlot > bs.Slot()+params.BeaconConfig().SlotsPerEpoch {
+		t.Errorf("Assigned slot %d can't be higher than %d",
+			res.CurrentEpochDuties[0].AttesterSlot, bs.Slot()+params.BeaconConfig().SlotsPerEpoch)
+	}
+
+	// We request for duties for all validators.
+	req = &ethpb.DutiesRequest{
+		PublicKeys: pubKeys,
+		Epoch:      0,
+	}
+	res, err = vs.GetDutiesV2(context.Background(), req)
+	require.NoError(t, err, "Could not call epoch committee assignment")
+	for i := 0; i < len(res.CurrentEpochDuties); i++ {
+		assert.Equal(t, primitives.ValidatorIndex(i), res.CurrentEpochDuties[i].ValidatorIndex)
+	}
+	for i := 0; i < len(res.CurrentEpochDuties); i++ {
+		assert.Equal(t, true, res.CurrentEpochDuties[i].IsSyncCommittee)
+		// Current epoch and next epoch duties should be equal before the sync period epoch boundary.
+		assert.Equal(t, res.CurrentEpochDuties[i].IsSyncCommittee, res.NextEpochDuties[i].IsSyncCommittee)
+	}
+
+	// Current epoch and next epoch duties should not be equal at the sync period epoch boundary.
+	req = &ethpb.DutiesRequest{
+		PublicKeys: pubKeys,
+		Epoch:      params.BeaconConfig().EpochsPerSyncCommitteePeriod - 1,
+	}
+	res, err = vs.GetDutiesV2(context.Background(), req)
+	require.NoError(t, err, "Could not call epoch committee assignment")
+	for i := 0; i < len(res.CurrentEpochDuties); i++ {
+		require.NotEqual(t, res.CurrentEpochDuties[i].IsSyncCommittee, res.NextEpochDuties[i].IsSyncCommittee)
+	}
+}
+
+func TestGetAltairDutiesV2_UnknownPubkey(t *testing.T) {
+	params.SetupTestConfigCleanup(t)
+	cfg := params.BeaconConfig().Copy()
+	cfg.AltairForkEpoch = primitives.Epoch(0)
+	params.OverrideBeaconConfig(cfg)
+
+	genesis := util.NewBeaconBlock()
+	deposits, _, err := util.DeterministicDepositsAndKeys(params.BeaconConfig().SyncCommitteeSize)
+	require.NoError(t, err)
+	eth1Data, err := util.DeterministicEth1Data(len(deposits))
+	require.NoError(t, err)
+	bs, err := util.GenesisBeaconState(context.Background(), deposits, 0, eth1Data)
+	require.NoError(t, err)
+	h := &ethpb.BeaconBlockHeader{
+		StateRoot:  bytesutil.PadTo([]byte{'a'}, fieldparams.RootLength),
+		ParentRoot: bytesutil.PadTo([]byte{'b'}, fieldparams.RootLength),
+		BodyRoot:   bytesutil.PadTo([]byte{'c'}, fieldparams.RootLength),
+	}
+	require.NoError(t, bs.SetLatestBlockHeader(h))
+	require.NoError(t, err, "Could not setup genesis bs")
+	genesisRoot, err := genesis.Block.HashTreeRoot()
+	require.NoError(t, err, "Could not get signing root")
+
+	require.NoError(t, bs.SetSlot(params.BeaconConfig().SlotsPerEpoch*primitives.Slot(params.BeaconConfig().EpochsPerSyncCommitteePeriod)-1))
+	require.NoError(t, helpers.UpdateSyncCommitteeCache(bs))
+
+	slot := uint64(params.BeaconConfig().SlotsPerEpoch) * uint64(params.BeaconConfig().EpochsPerSyncCommitteePeriod) * params.BeaconConfig().SecondsPerSlot
+	chain := &mockChain.ChainService{
+		State: bs, Root: genesisRoot[:], Genesis: time.Now().Add(time.Duration(-1*int64(slot-1)) * time.Second),
+	}
+	depositCache, err := depositsnapshot.New()
+	require.NoError(t, err)
+
+	vs := &Server{
+		HeadFetcher:       chain,
+		ForkchoiceFetcher: chain,
+		TimeFetcher:       chain,
+		Eth1InfoFetcher:   &mockExecution.Chain{},
+		SyncChecker:       &mockSync.Sync{IsSyncing: false},
+		DepositFetcher:    depositCache,
+		PayloadIDCache:    cache.NewPayloadIDCache(),
+	}
+
+	unknownPubkey := bytesutil.PadTo([]byte{'u'}, 48)
+
+	req := &ethpb.DutiesRequest{
+		PublicKeys: [][]byte{unknownPubkey},
+	}
+	res, err := vs.GetDutiesV2(context.Background(), req)
+	require.NoError(t, err)
+	assert.Equal(t, false, res.CurrentEpochDuties[0].IsSyncCommittee)
+	assert.Equal(t, false, res.NextEpochDuties[0].IsSyncCommittee)
+}
+
+func TestGetDutiesV2_StateAdvancement(t *testing.T) {
+	params.SetupTestConfigCleanup(t)
+	cfg := params.BeaconConfig().Copy()
+	cfg.ElectraForkEpoch = primitives.Epoch(0)
+	params.OverrideBeaconConfig(cfg)
+
+	epochStart, err := slots.EpochStart(1)
+	require.NoError(t, err)
+	st, _ := util.DeterministicGenesisStateElectra(t, 1)
+	require.NoError(t, st.SetSlot(epochStart-1))
+
+	// Request epoch 1 which requires slot 32 processing
+	req := &ethpb.DutiesRequest{
+		PublicKeys: [][]byte{pubKey(0)},
+		Epoch:      1,
+	}
+	b, err := blocks.NewSignedBeaconBlock(util.HydrateSignedBeaconBlockElectra(&ethpb.SignedBeaconBlockElectra{}))
+	require.NoError(t, err)
+	b.SetSlot(epochStart)
+	currentSlot := epochStart - 1
+	// Mock chain service with state at slot 0
+	chain := &mockChain.ChainService{
+		Root:  make([]byte, 32),
+		State: st,
+		Block: b,
+		Slot:  &currentSlot,
+	}
+
+	vs := &Server{
+		HeadFetcher:       chain,
+		TimeFetcher:       chain,
+		ForkchoiceFetcher: chain,
+		SyncChecker:       &mockSync.Sync{IsSyncing: false},
+	}
+
+	// Verify state processing occurs
+	res, err := vs.GetDutiesV2(context.Background(), req)
+	require.NoError(t, err)
+	require.NotNil(t, res)
+}
+
+func TestGetDutiesV2_SlotOutOfUpperBound(t *testing.T) {
+	chain := &mockChain.ChainService{
+		Genesis: time.Now(),
+	}
+	vs := &Server{
+		ForkchoiceFetcher: chain,
+		TimeFetcher:       chain,
+		SyncChecker:       &mockSync.Sync{IsSyncing: false},
+	}
+	req := &ethpb.DutiesRequest{
+		Epoch: primitives.Epoch(chain.CurrentSlot()/params.BeaconConfig().SlotsPerEpoch + 2),
+	}
+	_, err := vs.GetDutiesV2(context.Background(), req)
+	require.ErrorContains(t, "can not be greater than next epoch", err)
+}
+
+func TestGetDutiesV2_CurrentEpoch_ShouldNotFail(t *testing.T) {
+	genesis := util.NewBeaconBlock()
+	depChainStart := params.BeaconConfig().MinGenesisActiveValidatorCount
+	deposits, _, err := util.DeterministicDepositsAndKeys(depChainStart)
+	require.NoError(t, err)
+	eth1Data, err := util.DeterministicEth1Data(len(deposits))
+	require.NoError(t, err)
+	bState, err := transition.GenesisBeaconState(context.Background(), deposits, 0, eth1Data)
+	require.NoError(t, err, "Could not setup genesis state")
+	// Set state to non-epoch start slot.
+	require.NoError(t, bState.SetSlot(5))
+
+	genesisRoot, err := genesis.Block.HashTreeRoot()
+	require.NoError(t, err, "Could not get signing root")
+
+	pubKeys := make([][fieldparams.BLSPubkeyLength]byte, len(deposits))
+	indices := make([]uint64, len(deposits))
+	for i := 0; i < len(deposits); i++ {
+		pubKeys[i] = bytesutil.ToBytes48(deposits[i].Data.PublicKey)
+		indices[i] = uint64(i)
+	}
+
+	chain := &mockChain.ChainService{
+		State: bState, Root: genesisRoot[:], Genesis: time.Now(),
+	}
+	vs := &Server{
+		HeadFetcher:       chain,
+		ForkchoiceFetcher: chain,
+		TimeFetcher:       chain,
+		SyncChecker:       &mockSync.Sync{IsSyncing: false},
+		PayloadIDCache:    cache.NewPayloadIDCache(),
+	}
+
+	// Test the first validator in registry.
+	req := &ethpb.DutiesRequest{
+		PublicKeys: [][]byte{deposits[0].Data.PublicKey},
+	}
+	res, err := vs.GetDutiesV2(context.Background(), req)
+	require.NoError(t, err)
+	assert.Equal(t, 1, len(res.CurrentEpochDuties), "Expected 1 assignment")
+}
+
+func TestGetDutiesV2_MultipleKeys_OK(t *testing.T) {
+	genesis := util.NewBeaconBlock()
+	depChainStart := uint64(64)
+
+	deposits, _, err := util.DeterministicDepositsAndKeys(depChainStart)
+	require.NoError(t, err)
+	eth1Data, err := util.DeterministicEth1Data(len(deposits))
+	require.NoError(t, err)
+	bs, err := transition.GenesisBeaconState(context.Background(), deposits, 0, eth1Data)
+	require.NoError(t, err, "Could not setup genesis bs")
+	genesisRoot, err := genesis.Block.HashTreeRoot()
+	require.NoError(t, err, "Could not get signing root")
+
+	pubKeys := make([][fieldparams.BLSPubkeyLength]byte, len(deposits))
+	indices := make([]uint64, len(deposits))
+	for i := 0; i < len(deposits); i++ {
+		pubKeys[i] = bytesutil.ToBytes48(deposits[i].Data.PublicKey)
+		indices[i] = uint64(i)
+	}
+
+	chain := &mockChain.ChainService{
+		State: bs, Root: genesisRoot[:], Genesis: time.Now(),
+	}
+	vs := &Server{
+		HeadFetcher:       chain,
+		ForkchoiceFetcher: chain,
+		TimeFetcher:       chain,
+		SyncChecker:       &mockSync.Sync{IsSyncing: false},
+		PayloadIDCache:    cache.NewPayloadIDCache(),
+	}
+
+	pubkey0 := deposits[0].Data.PublicKey
+	pubkey1 := deposits[1].Data.PublicKey
+
+	// Test the first validator in registry.
+	req := &ethpb.DutiesRequest{
+		PublicKeys: [][]byte{pubkey0, pubkey1},
+	}
+	res, err := vs.GetDutiesV2(context.Background(), req)
+	require.NoError(t, err, "Could not call epoch committee assignment")
+	assert.Equal(t, 2, len(res.CurrentEpochDuties))
+	assert.Equal(t, primitives.Slot(4), res.CurrentEpochDuties[0].AttesterSlot)
+	assert.Equal(t, primitives.Slot(4), res.CurrentEpochDuties[1].AttesterSlot)
+}
+
+func TestGetDutiesV2_NextSyncCommitteePeriod(t *testing.T) {
+	params.SetupTestConfigCleanup(t)
+	cfg := params.BeaconConfig().Copy()
+	cfg.AltairForkEpoch = primitives.Epoch(0)
+	cfg.EpochsPerSyncCommitteePeriod = 1
+	params.OverrideBeaconConfig(cfg)
+
+	// Configure sync committee period boundary
+	epochsPerPeriod := params.BeaconConfig().EpochsPerSyncCommitteePeriod
+	boundaryEpoch := epochsPerPeriod - 1
+
+	// Create state at last epoch of current period
+	deposits, _, err := util.DeterministicDepositsAndKeys(params.BeaconConfig().SyncCommitteeSize)
+	require.NoError(t, err)
+	eth1Data, err := util.DeterministicEth1Data(len(deposits))
+	require.NoError(t, err)
+	st, err := util.GenesisBeaconState(context.Background(), deposits, 0, eth1Data)
+	require.NoError(t, err)
+
+	syncCommittee, err := altair.NextSyncCommittee(context.Background(), st)
+	require.NoError(t, err)
+	require.NoError(t, st.SetCurrentSyncCommittee(syncCommittee))
+	require.NoError(t, st.SetSlot(params.BeaconConfig().SlotsPerEpoch*primitives.Slot(boundaryEpoch)))
+
+	validatorPubkey := deposits[0].Data.PublicKey
+
+	// Request duties for boundary epoch + 1
+	req := &ethpb.DutiesRequest{
+		PublicKeys: [][]byte{validatorPubkey},
+		Epoch:      boundaryEpoch + 1,
+	}
+
+	genesisRoot := [32]byte{}
+	chain := &mockChain.ChainService{
+		State: st,
+		Root:  genesisRoot[:],
+	}
+	vs := &Server{
+		HeadFetcher:       chain,
+		TimeFetcher:       chain,
+		ForkchoiceFetcher: chain,
+		SyncChecker:       &mockSync.Sync{IsSyncing: false},
+	}
+
+	res, err := vs.GetDutiesV2(context.Background(), req)
+	require.NoError(t, err)
+
+	//Verify next epoch duties have updated sync committee status
+	require.NotEqual(t,
+		res.CurrentEpochDuties[0].IsSyncCommittee,
+		res.NextEpochDuties[0].IsSyncCommittee,
+	)
+}
+
+func TestGetDutiesV2_SyncNotReady(t *testing.T) {
+	vs := &Server{
+		SyncChecker: &mockSync.Sync{IsSyncing: true},
+	}
+	_, err := vs.GetDutiesV2(context.Background(), &ethpb.DutiesRequest{})
+	assert.ErrorContains(t, "Syncing to latest head", err)
+}

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

@@ -15,9 +15,13 @@ import (
 	blockfeed "github.com/OffchainLabs/prysm/v6/beacon-chain/core/feed/block"
 	"github.com/OffchainLabs/prysm/v6/beacon-chain/core/feed/operation"
 	"github.com/OffchainLabs/prysm/v6/beacon-chain/core/helpers"
+	"github.com/OffchainLabs/prysm/v6/beacon-chain/core/peerdas"
+	coreTime "github.com/OffchainLabs/prysm/v6/beacon-chain/core/time"
 	"github.com/OffchainLabs/prysm/v6/beacon-chain/core/transition"
 	"github.com/OffchainLabs/prysm/v6/beacon-chain/db/kv"
 	"github.com/OffchainLabs/prysm/v6/beacon-chain/state"
+	"github.com/OffchainLabs/prysm/v6/config/features"
+	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"
@@ -58,28 +62,31 @@ func (vs *Server) GetBeaconBlock(ctx context.Context, req *ethpb.BlockRequest) (
 	if err != nil {
 		log.WithError(err).Error("Could not convert slot to time")
 	}
-	log.WithFields(logrus.Fields{
-		"slot":               req.Slot,
-		"sinceSlotStartTime": time.Since(t),
-	}).Info("Begin building block")
+
+	log := log.WithField("slot", req.Slot)
+	log.WithField("sinceSlotStartTime", time.Since(t)).Info("Begin building block")
 
 	// A syncing validator should not produce a block.
 	if vs.SyncChecker.Syncing() {
+		log.Error("Fail to build block: node is syncing")
 		return nil, status.Error(codes.Unavailable, "Syncing to latest head, not ready to respond")
 	}
 	// An optimistic validator MUST NOT produce a block (i.e., sign across the DOMAIN_BEACON_PROPOSER domain).
 	if slots.ToEpoch(req.Slot) >= params.BeaconConfig().BellatrixForkEpoch {
 		if err := vs.optimisticStatus(ctx); err != nil {
+			log.WithError(err).Error("Fail to build block: node is optimistic")
 			return nil, status.Errorf(codes.Unavailable, "Validator is not ready to propose: %v", err)
 		}
 	}
 
 	head, parentRoot, err := vs.getParentState(ctx, req.Slot)
 	if err != nil {
+		log.WithError(err).Error("Fail to build block: could not get parent state")
 		return nil, err
 	}
 	sBlk, err := getEmptyBlock(req.Slot)
 	if err != nil {
+		log.WithError(err).Error("Fail to build block: could not get empty block")
 		return nil, status.Errorf(codes.Internal, "Could not prepare block: %v", err)
 	}
 	// Set slot, graffiti, randao reveal, and parent root.
@@ -91,6 +98,7 @@ func (vs *Server) GetBeaconBlock(ctx context.Context, req *ethpb.BlockRequest) (
 	// Set proposer index.
 	idx, err := helpers.BeaconProposerIndex(ctx, head)
 	if err != nil {
+		log.WithError(err).Error("Fail to build block: could not calculate proposer index")
 		return nil, fmt.Errorf("could not calculate proposer index %w", err)
 	}
 	sBlk.SetProposerIndex(idx)
@@ -101,7 +109,7 @@ func (vs *Server) GetBeaconBlock(ctx context.Context, req *ethpb.BlockRequest) (
 	}
 
 	resp, err := vs.BuildBlockParallel(ctx, sBlk, head, req.SkipMevBoost, builderBoostFactor)
-	log := log.WithFields(logrus.Fields{
+	log = log.WithFields(logrus.Fields{
 		"slot":               req.Slot,
 		"sinceSlotStartTime": time.Since(t),
 		"validator":          sBlk.Block().ProposerIndex(),
@@ -232,7 +240,7 @@ 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 {
@@ -274,7 +282,13 @@ func (vs *Server) BuildBlockParallel(ctx context.Context, sBlk interfaces.Signed
 // Deprecated: The gRPC API will remain the default and fully supported through v8 (expected in 2026) but will be eventually removed in favor of REST API.
 //
 // ProposeBeaconBlock handles the proposal of beacon blocks.
+// TODO: Add tests
 func (vs *Server) ProposeBeaconBlock(ctx context.Context, req *ethpb.GenericSignedBeaconBlock) (*ethpb.ProposeResponse, error) {
+	var (
+		blobSidecars       []*ethpb.BlobSidecar
+		dataColumnSideCars []*ethpb.DataColumnSidecar
+	)
+
 	ctx, span := trace.StartSpan(ctx, "ProposerServer.ProposeBeaconBlock")
 	defer span.End()
 
@@ -286,12 +300,12 @@ func (vs *Server) ProposeBeaconBlock(ctx context.Context, req *ethpb.GenericSign
 	if err != nil {
 		return nil, status.Errorf(codes.InvalidArgument, "%s: %v", "decode block failed", err)
 	}
+	isPeerDASEnabled := coreTime.PeerDASIsActive(block.Block().Slot())
 
-	var sidecars []*ethpb.BlobSidecar
 	if block.IsBlinded() {
-		block, sidecars, err = vs.handleBlindedBlock(ctx, block)
+		block, blobSidecars, dataColumnSideCars, err = vs.handleBlindedBlock(ctx, block, isPeerDASEnabled)
 	} else if block.Version() >= version.Deneb {
-		sidecars, err = vs.blobSidecarsFromUnblindedBlock(block, req)
+		blobSidecars, dataColumnSideCars, err = vs.handleUnblindedBlock(block, req, isPeerDASEnabled)
 	}
 	if err != nil {
 		return nil, status.Errorf(codes.Internal, "%s: %v", "handle block failed", err)
@@ -302,9 +316,10 @@ func (vs *Server) ProposeBeaconBlock(ctx context.Context, req *ethpb.GenericSign
 		return nil, status.Errorf(codes.Internal, "Could not hash tree root: %v", err)
 	}
 
+	slot := block.Block().Slot()
+
 	var wg sync.WaitGroup
 	errChan := make(chan error, 1)
-
 	wg.Add(1)
 	go func() {
 		defer wg.Done()
@@ -315,8 +330,14 @@ func (vs *Server) ProposeBeaconBlock(ctx context.Context, req *ethpb.GenericSign
 		errChan <- nil
 	}()
 
-	if err := vs.broadcastAndReceiveBlobs(ctx, sidecars, root); err != nil {
-		return nil, status.Errorf(codes.Internal, "Could not broadcast/receive blobs: %v", err)
+	if isPeerDASEnabled {
+		if err := vs.broadcastAndReceiveDataColumns(ctx, dataColumnSideCars, root, slot); err != nil {
+			return nil, status.Errorf(codes.Internal, "Could not broadcast/receive data columns: %v", err)
+		}
+	} else {
+		if err := vs.broadcastAndReceiveBlobs(ctx, blobSidecars, root); err != nil {
+			return nil, status.Errorf(codes.Internal, "Could not broadcast/receive blobs: %v", err)
+		}
 	}
 
 	wg.Wait()
@@ -328,46 +349,75 @@ func (vs *Server) ProposeBeaconBlock(ctx context.Context, req *ethpb.GenericSign
 }
 
 // handleBlindedBlock processes blinded beacon blocks.
-func (vs *Server) handleBlindedBlock(ctx context.Context, block interfaces.SignedBeaconBlock) (interfaces.SignedBeaconBlock, []*ethpb.BlobSidecar, error) {
+func (vs *Server) handleBlindedBlock(ctx context.Context, block interfaces.SignedBeaconBlock, isPeerDASEnabled bool) (interfaces.SignedBeaconBlock, []*ethpb.BlobSidecar, []*ethpb.DataColumnSidecar, error) {
 	if block.Version() < version.Bellatrix {
-		return nil, nil, errors.New("pre-Bellatrix blinded block")
+		return nil, nil, nil, errors.New("pre-Bellatrix blinded block")
 	}
+
 	if vs.BlockBuilder == nil || !vs.BlockBuilder.Configured() {
-		return nil, nil, errors.New("unconfigured block builder")
+		return nil, nil, nil, errors.New("unconfigured block builder")
 	}
 
 	copiedBlock, err := block.Copy()
 	if err != nil {
-		return nil, nil, err
+		return nil, nil, nil, errors.Wrap(err, "block copy")
 	}
 
 	payload, bundle, err := vs.BlockBuilder.SubmitBlindedBlock(ctx, block)
 	if err != nil {
-		return nil, nil, errors.Wrap(err, "submit blinded block failed")
+		return nil, nil, nil, errors.Wrap(err, "submit blinded block")
 	}
 
 	if err := copiedBlock.Unblind(payload); err != nil {
-		return nil, nil, errors.Wrap(err, "unblind failed")
+		return nil, nil, nil, errors.Wrap(err, "unblind")
 	}
 
-	sidecars, err := unblindBlobsSidecars(copiedBlock, bundle)
+	if isPeerDASEnabled {
+		dataColumnSideCars, err := peerdas.ConstructDataColumnSidecars(block, bundle.GetBlobs(), bundle.GetProofs())
+		if err != nil {
+			return nil, nil, nil, errors.Wrap(err, "construct data column sidecars")
+		}
+
+		return copiedBlock, nil, dataColumnSideCars, nil
+	}
+
+	blobSidecars, err := unblindBlobsSidecars(copiedBlock, bundle)
 	if err != nil {
-		return nil, nil, errors.Wrap(err, "unblind blobs sidecars: commitment value doesn't match block")
+		return nil, nil, nil, errors.Wrap(err, "unblind blobs sidecars: commitment value doesn't match block")
 	}
 
-	return copiedBlock, sidecars, nil
+	return copiedBlock, blobSidecars, nil, nil
 }
 
-func (vs *Server) blobSidecarsFromUnblindedBlock(block interfaces.SignedBeaconBlock, req *ethpb.GenericSignedBeaconBlock) ([]*ethpb.BlobSidecar, error) {
+func (vs *Server) handleUnblindedBlock(
+	block interfaces.SignedBeaconBlock,
+	req *ethpb.GenericSignedBeaconBlock,
+	isPeerDASEnabled bool,
+) ([]*ethpb.BlobSidecar, []*ethpb.DataColumnSidecar, error) {
 	rawBlobs, proofs, err := blobsAndProofs(req)
 	if err != nil {
-		return nil, err
+		return nil, nil, err
 	}
-	return BuildBlobSidecars(block, rawBlobs, proofs)
+
+	if isPeerDASEnabled {
+		dataColumnSideCars, err := peerdas.ConstructDataColumnSidecars(block, rawBlobs, proofs)
+		if err != nil {
+			return nil, nil, errors.Wrap(err, "construct data column sidecars")
+		}
+
+		return nil, dataColumnSideCars, nil
+	}
+
+	blobSidecars, err := BuildBlobSidecars(block, rawBlobs, proofs)
+	if err != nil {
+		return nil, nil, errors.Wrap(err, "build blob sidecars")
+	}
+
+	return blobSidecars, nil, nil
 }
 
 // broadcastReceiveBlock broadcasts a block and handles its reception.
-func (vs *Server) broadcastReceiveBlock(ctx context.Context, block interfaces.SignedBeaconBlock, root [32]byte) error {
+func (vs *Server) broadcastReceiveBlock(ctx context.Context, block interfaces.SignedBeaconBlock, root [fieldparams.RootLength]byte) error {
 	protoBlock, err := block.Proto()
 	if err != nil {
 		return errors.Wrap(err, "protobuf conversion failed")
@@ -383,7 +433,7 @@ func (vs *Server) broadcastReceiveBlock(ctx context.Context, block interfaces.Si
 }
 
 // broadcastAndReceiveBlobs handles the broadcasting and reception of blob sidecars.
-func (vs *Server) broadcastAndReceiveBlobs(ctx context.Context, sidecars []*ethpb.BlobSidecar, root [32]byte) error {
+func (vs *Server) broadcastAndReceiveBlobs(ctx context.Context, sidecars []*ethpb.BlobSidecar, root [fieldparams.RootLength]byte) error {
 	eg, eCtx := errgroup.WithContext(ctx)
 	for i, sc := range sidecars {
 		// Copy the iteration instance to a local variable to give each go-routine its own copy to play with.
@@ -412,6 +462,69 @@ func (vs *Server) broadcastAndReceiveBlobs(ctx context.Context, sidecars []*ethp
 	return eg.Wait()
 }
 
+// broadcastAndReceiveDataColumns handles the broadcasting and reception of data columns sidecars.
+func (vs *Server) broadcastAndReceiveDataColumns(
+	ctx context.Context,
+	sidecars []*ethpb.DataColumnSidecar,
+	root [fieldparams.RootLength]byte,
+	slot primitives.Slot,
+) error {
+	dataColumnsWithholdCount := features.Get().DataColumnsWithholdCount
+	verifiedRODataColumns := make([]blocks.VerifiedRODataColumn, 0, len(sidecars))
+
+	eg, _ := errgroup.WithContext(ctx)
+	for _, sd := range sidecars {
+		roDataColumn, err := blocks.NewRODataColumnWithRoot(sd, root)
+		if err != nil {
+			return errors.Wrap(err, "new read-only data column with root")
+		}
+
+		// We build this block ourselves, so we can upgrade the read only data column sidecar into a verified one.
+		verifiedRODataColumn := blocks.NewVerifiedRODataColumn(roDataColumn)
+		verifiedRODataColumns = append(verifiedRODataColumns, verifiedRODataColumn)
+
+		// Copy the iteration instance to a local variable to give each go-routine its own copy to play with.
+		// See https://golang.org/doc/faq#closures_and_goroutines for more details.
+		sidecar := sd
+		eg.Go(func() error {
+			if sidecar.Index < dataColumnsWithholdCount {
+				log.WithFields(logrus.Fields{
+					"root":  fmt.Sprintf("%#x", root),
+					"slot":  slot,
+					"index": sidecar.Index,
+				}).Warning("Withholding data column")
+
+				return nil
+			}
+
+			// Compute the subnet index based on the column index.
+			subnet := peerdas.ComputeSubnetForDataColumnSidecar(sidecar.Index)
+
+			if err := vs.P2P.BroadcastDataColumn(root, subnet, sidecar); err != nil {
+				return errors.Wrap(err, "broadcast data column")
+			}
+
+			return nil
+		})
+	}
+
+	if err := eg.Wait(); err != nil {
+		return errors.Wrap(err, "wait for data columns to be broadcasted")
+	}
+
+	if err := vs.DataColumnReceiver.ReceiveDataColumns(verifiedRODataColumns); err != nil {
+		return errors.Wrap(err, "receive data column")
+	}
+
+	for _, verifiedRODataColumn := range verifiedRODataColumns {
+		vs.OperationNotifier.OperationFeed().Send(&feed.Event{
+			Type: operation.DataColumnSidecarReceived,
+			Data: &operation.DataColumnSidecarReceivedData{DataColumn: &verifiedRODataColumn}, // #nosec G601
+		})
+	}
+	return nil
+}
+
 // Deprecated: The gRPC API will remain the default and fully supported through v8 (expected in 2026) but will be eventually removed in favor of REST API.
 //
 // PrepareBeaconProposer caches and updates the fee recipient for the given proposer.

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

@@ -520,7 +520,7 @@ func TestServer_setExecutionData(t *testing.T) {
 			PayloadIDBytes: id,
 			GetPayloadResponse: &blocks.GetPayloadResponse{
 				ExecutionData: ed,
-				BlobsBundle:   blobsBundle,
+				BlobsBundler:  blobsBundle,
 				Bid:           primitives.ZeroWei(),
 			},
 		}
@@ -528,7 +528,7 @@ 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/rpc/prysm/v1alpha1/validator/server.go

@@ -67,6 +67,7 @@ type Server struct {
 	SyncCommitteePool       synccommittee.Pool
 	BlockReceiver           blockchain.BlockReceiver
 	BlobReceiver            blockchain.BlobReceiver
+	DataColumnReceiver      blockchain.DataColumnReceiver
 	MockEth1Votes           bool
 	Eth1BlockFetcher        execution.POWBlockFetcher
 	PendingDepositsFetcher  depositsnapshot.PendingDepositsFetcher

beacon-chain/rpc/service.go

@@ -89,6 +89,7 @@ type Config struct {
 	AttestationReceiver       blockchain.AttestationReceiver
 	BlockReceiver             blockchain.BlockReceiver
 	BlobReceiver              blockchain.BlobReceiver
+	DataColumnReceiver        blockchain.DataColumnReceiver
 	ExecutionChainService     execution.Chain
 	ChainStartFetcher         execution.ChainStartFetcher
 	ExecutionChainInfoFetcher execution.ChainInfoFetcher
@@ -120,6 +121,7 @@ type Config struct {
 	Router                    *http.ServeMux
 	ClockWaiter               startup.ClockWaiter
 	BlobStorage               *filesystem.BlobStorage
+	DataColumnStorage         *filesystem.DataColumnStorage
 	TrackedValidatorsCache    *cache.TrackedValidatorsCache
 	PayloadIDCache            *cache.PayloadIDCache
 	LCStore                   *lightClient.Store
@@ -196,6 +198,7 @@ func NewService(ctx context.Context, cfg *Config) *Service {
 		ChainInfoFetcher:   s.cfg.ChainInfoFetcher,
 		GenesisTimeFetcher: s.cfg.GenesisTimeFetcher,
 		BlobStorage:        s.cfg.BlobStorage,
+		DataColumnStorage:  s.cfg.DataColumnStorage,
 	}
 	rewardFetcher := &rewards.BlockRewardService{Replayer: ch, DB: s.cfg.BeaconDB}
 	coreService := &core.Service{
@@ -236,6 +239,7 @@ func NewService(ctx context.Context, cfg *Config) *Service {
 		P2P:                     s.cfg.Broadcaster,
 		BlockReceiver:           s.cfg.BlockReceiver,
 		BlobReceiver:            s.cfg.BlobReceiver,
+		DataColumnReceiver:      s.cfg.DataColumnReceiver,
 		MockEth1Votes:           s.cfg.MockEth1Votes,
 		Eth1BlockFetcher:        s.cfg.ExecutionChainService,
 		PendingDepositsFetcher:  s.cfg.PendingDepositFetcher,

beacon-chain/rpc/testutil/mock_blocker.go

@@ -36,6 +36,6 @@ func (m *MockBlocker) Block(_ context.Context, b []byte) (interfaces.ReadOnlySig
 }
 
 // Blobs --
-func (m *MockBlocker) Blobs(_ context.Context, _ string, _ []uint64) ([]*blocks.VerifiedROBlob, *core.RpcError) {
-	panic("implement me") // lint:nopanic -- Test code.
+func (*MockBlocker) Blobs(_ context.Context, _ string, _ []int) ([]*blocks.VerifiedROBlob, *core.RpcError) {
+	return nil, &core.RpcError{}
 }

beacon-chain/state/interfaces.go

@@ -61,6 +61,7 @@ type ReadOnlyBeaconState interface {
 	ReadOnlySyncCommittee
 	ReadOnlyDeposits
 	ReadOnlyConsolidations
+	ReadOnlyProposerLookahead
 	ToProtoUnsafe() interface{}
 	ToProto() interface{}
 	GenesisTime() uint64
@@ -95,6 +96,7 @@ type WriteOnlyBeaconState interface {
 	WriteOnlyConsolidations
 	WriteOnlyWithdrawals
 	WriteOnlyDeposits
+	WriteOnlyProposerLookahead
 	SetGenesisTime(val uint64) error
 	SetGenesisValidatorsRoot(val []byte) error
 	SetSlot(val primitives.Slot) error
@@ -239,6 +241,10 @@ type ReadOnlyConsolidations interface {
 	NumPendingConsolidations() (uint64, error)
 }
 
+type ReadOnlyProposerLookahead interface {
+	ProposerLookahead() ([]primitives.ValidatorIndex, error)
+}
+
 // WriteOnlyBlockRoots defines a struct which only has write access to block roots methods.
 type WriteOnlyBlockRoots interface {
 	SetBlockRoots(val [][]byte) error
@@ -340,3 +346,7 @@ type WriteOnlyDeposits interface {
 	SetPendingDeposits(val []*ethpb.PendingDeposit) error
 	SetDepositBalanceToConsume(primitives.Gwei) error
 }
+
+type WriteOnlyProposerLookahead interface {
+	SetProposerLookahead([]primitives.ValidatorIndex) error
+}

beacon-chain/state/state-native/BUILD.bazel

@@ -17,6 +17,7 @@ go_library(
         "getters_misc.go",
         "getters_participation.go",
         "getters_payload_header.go",
+        "getters_proposer_lookahead.go",
         "getters_randao.go",
         "getters_state.go",
         "getters_sync_committee.go",
@@ -37,6 +38,7 @@ go_library(
         "setters_misc.go",
         "setters_participation.go",
         "setters_payload_header.go",
+        "setters_proposer_lookahead.go",
         "setters_randao.go",
         "setters_state.go",
         "setters_sync_committee.go",
@@ -97,6 +99,7 @@ go_test(
         "getters_deposits_test.go",
         "getters_exit_test.go",
         "getters_participation_test.go",
+        "getters_setters_lookahead_test.go",
         "getters_test.go",
         "getters_validator_test.go",
         "getters_withdrawal_test.go",

beacon-chain/state/state-native/README.md

@@ -3,7 +3,7 @@
 Note: Whenever only the name of a file is provided, it's assumed to be in the `/beacon-chain/state/state-native` package.
 
 - Add a `BeaconState[Version]FieldCount` configuration item to `/config/params/config.go` and set it in `/config/params/mainnet_config.go`.
-- Add the field to the `BeaconState` struct in `beacon_state_mainnet.go` and `beacon_state_minimal.go`. Update the marshaling code too.
+- Add the field to the `BeaconState` struct in `beacon_state.go`. Update the marshaling structs in the same file too.
 - Add the field's metadata to `/beacon-chain/state/state-native/types/types.go`.
 - Add a getter and a setter for the field, either to existing `getter_XXX.go`/`setter_XXX.go` files or create new ones if the field doesn't fit anywhere.
 Add the new getter and setter to `/beacon-chain/state/interfaces.go`.
@@ -19,6 +19,6 @@ between states.
   - Add the following functions: `InitializeFromProto[Version]()`, `InitializeFromProtoUnsafe[Version]()`.
   - Update the following functions: `Copy()`, `initializeMerkleLayers()`, `RecordStateMetrics()` (applies only to multi-value slice fields), `rootSelector()`,
 `finalizerCleanup()` (applies only to multi-value slice fields).
-- If the field is a slice, add it to the field map in `types.go`.
+- If the field is a slice, add it to the field map in `types.go`. This only applies to large slices that need to be rehashed only in part. In particular, this mostly applies for arrays of objects, and not for arrays of basic SSZ types as these are not hashed by taking the root of each element. 
 - If the field is a slice, update the `fieldConverters()` function in `/beacon-chain/state/fieldtrie/field_trie_helpers.go`. The exact implementation will vary
-depending on a few factors (is the field similar to an existing one, is it a multi-value slice etc.)
+depending on a few factors (is the field similar to an existing one, is it a multi-value slice etc). This applies only for the slices as mentioned in the previous comment. 

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

@@ -70,6 +70,7 @@ type BeaconState struct {
 	pendingDeposits               []*ethpb.PendingDeposit           // pending_deposits: List[PendingDeposit, PENDING_DEPOSITS_LIMIT]
 	pendingPartialWithdrawals     []*ethpb.PendingPartialWithdrawal // pending_partial_withdrawals: List[PartialWithdrawal, PENDING_PARTIAL_WITHDRAWALS_LIMIT]
 	pendingConsolidations         []*ethpb.PendingConsolidation     // pending_consolidations: List[PendingConsolidation, PENDING_CONSOLIDATIONS_LIMIT]
+	proposerLookahead             []primitives.ValidatorIndex       // proposer_look_ahead: List[uint64, (MIN_LOOKAHEAD + 1)*SLOTS_PER_EPOCH]
 
 	id                    uint64
 	lock                  sync.RWMutex
@@ -125,6 +126,7 @@ type beaconStateMarshalable struct {
 	PendingDeposits                     []*ethpb.PendingDeposit                 `json:"pending_deposits" yaml:"pending_deposits"`
 	PendingPartialWithdrawals           []*ethpb.PendingPartialWithdrawal       `json:"pending_partial_withdrawals" yaml:"pending_partial_withdrawals"`
 	PendingConsolidations               []*ethpb.PendingConsolidation           `json:"pending_consolidations" yaml:"pending_consolidations"`
+	ProposerLookahead                   []primitives.ValidatorIndex             `json:"proposer_look_ahead" yaml:"proposer_look_ahead"`
 }
 
 func (b *BeaconState) MarshalJSON() ([]byte, error) {
@@ -194,6 +196,7 @@ func (b *BeaconState) MarshalJSON() ([]byte, error) {
 		PendingDeposits:                     b.pendingDeposits,
 		PendingPartialWithdrawals:           b.pendingPartialWithdrawals,
 		PendingConsolidations:               b.pendingConsolidations,
+		ProposerLookahead:                   b.proposerLookahead,
 	}
 	return json.Marshal(marshalable)
 }

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

@@ -0,0 +1,19 @@
+package state_native
+
+import (
+	"slices"
+
+	"github.com/OffchainLabs/prysm/v6/consensus-types/primitives"
+	"github.com/OffchainLabs/prysm/v6/runtime/version"
+)
+
+// ProposerLookahead is a non-mutating call to the beacon state which returns a slice of
+// validator indices that hold the  proposers in the next few slots.
+func (b *BeaconState) ProposerLookahead() ([]primitives.ValidatorIndex, error) {
+	if b.version < version.Fulu {
+		return nil, errNotSupported("ProposerLookahead", b.version)
+	}
+	b.lock.RLock()
+	defer b.lock.RUnlock()
+	return slices.Clone(b.proposerLookahead), nil
+}

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

@@ -0,0 +1,44 @@
+package state_native_test
+
+import (
+	"testing"
+
+	state_native "github.com/OffchainLabs/prysm/v6/beacon-chain/state/state-native"
+	"github.com/OffchainLabs/prysm/v6/config/params"
+	"github.com/OffchainLabs/prysm/v6/consensus-types/primitives"
+	ethpb "github.com/OffchainLabs/prysm/v6/proto/prysm/v1alpha1"
+	"github.com/OffchainLabs/prysm/v6/testing/require"
+)
+
+func TestProposerLookahead(t *testing.T) {
+	t.Run("Fulu expected values", func(t *testing.T) {
+		lookahead := make([]uint64, int(params.BeaconConfig().MinSeedLookahead+1)*int(params.BeaconConfig().SlotsPerEpoch))
+		want := make([]primitives.ValidatorIndex, int(params.BeaconConfig().MinSeedLookahead+1)*int(params.BeaconConfig().SlotsPerEpoch))
+		st, err := state_native.InitializeFromProtoFulu(&ethpb.BeaconStateFulu{
+			ProposerLookahead: lookahead,
+		})
+		require.NoError(t, err)
+		got, err := st.ProposerLookahead()
+		require.NoError(t, err)
+		require.Equal(t, len(want), len(got))
+		for i, w := range want {
+			require.Equal(t, w, got[i], "index %d", i)
+		}
+	})
+
+	t.Run("Fulu error on invalid size", func(t *testing.T) {
+		lookahead := make([]primitives.ValidatorIndex, int(params.BeaconConfig().MinSeedLookahead+1)*int(params.BeaconConfig().SlotsPerEpoch)+1)
+		st, err := state_native.InitializeFromProtoFulu(&ethpb.BeaconStateFulu{})
+		require.NoError(t, err)
+		require.ErrorContains(t, "invalid size for proposer lookahead", st.SetProposerLookahead(lookahead))
+	})
+
+	t.Run("earlier than electra returns error", func(t *testing.T) {
+		st, err := state_native.InitializeFromProtoDeneb(&ethpb.BeaconStateDeneb{})
+		require.NoError(t, err)
+		_, err = st.ProposerLookahead()
+		require.ErrorContains(t, "is not supported", err)
+		lookahead := make([]primitives.ValidatorIndex, int(params.BeaconConfig().MinSeedLookahead+1)*int(params.BeaconConfig().SlotsPerEpoch))
+		require.ErrorContains(t, "is not supported", st.SetProposerLookahead(lookahead))
+	})
+}

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

@@ -182,7 +182,7 @@ func (b *BeaconState) ToProtoUnsafe() interface{} {
 			NextWithdrawalValidatorIndex: b.nextWithdrawalValidatorIndex,
 			HistoricalSummaries:          b.historicalSummaries,
 		}
-	case version.Electra, version.Fulu:
+	case version.Electra:
 		return &ethpb.BeaconStateElectra{
 			GenesisTime:                   b.genesisTime,
 			GenesisValidatorsRoot:         gvrCopy[:],
@@ -222,6 +222,51 @@ func (b *BeaconState) ToProtoUnsafe() interface{} {
 			PendingPartialWithdrawals:     b.pendingPartialWithdrawals,
 			PendingConsolidations:         b.pendingConsolidations,
 		}
+	case version.Fulu:
+		lookahead := make([]uint64, len(b.proposerLookahead))
+		for i, v := range b.proposerLookahead {
+			lookahead[i] = uint64(v)
+		}
+		return &ethpb.BeaconStateFulu{
+			GenesisTime:                   b.genesisTime,
+			GenesisValidatorsRoot:         gvrCopy[:],
+			Slot:                          b.slot,
+			Fork:                          b.fork,
+			LatestBlockHeader:             b.latestBlockHeader,
+			BlockRoots:                    br,
+			StateRoots:                    sr,
+			HistoricalRoots:               b.historicalRoots.Slice(),
+			Eth1Data:                      b.eth1Data,
+			Eth1DataVotes:                 b.eth1DataVotes,
+			Eth1DepositIndex:              b.eth1DepositIndex,
+			Validators:                    vals,
+			Balances:                      bals,
+			RandaoMixes:                   rm,
+			Slashings:                     b.slashings,
+			PreviousEpochParticipation:    b.previousEpochParticipation,
+			CurrentEpochParticipation:     b.currentEpochParticipation,
+			JustificationBits:             b.justificationBits,
+			PreviousJustifiedCheckpoint:   b.previousJustifiedCheckpoint,
+			CurrentJustifiedCheckpoint:    b.currentJustifiedCheckpoint,
+			FinalizedCheckpoint:           b.finalizedCheckpoint,
+			InactivityScores:              inactivityScores,
+			CurrentSyncCommittee:          b.currentSyncCommittee,
+			NextSyncCommittee:             b.nextSyncCommittee,
+			LatestExecutionPayloadHeader:  b.latestExecutionPayloadHeaderDeneb,
+			NextWithdrawalIndex:           b.nextWithdrawalIndex,
+			NextWithdrawalValidatorIndex:  b.nextWithdrawalValidatorIndex,
+			HistoricalSummaries:           b.historicalSummaries,
+			DepositRequestsStartIndex:     b.depositRequestsStartIndex,
+			DepositBalanceToConsume:       b.depositBalanceToConsume,
+			ExitBalanceToConsume:          b.exitBalanceToConsume,
+			EarliestExitEpoch:             b.earliestExitEpoch,
+			ConsolidationBalanceToConsume: b.consolidationBalanceToConsume,
+			EarliestConsolidationEpoch:    b.earliestConsolidationEpoch,
+			PendingDeposits:               b.pendingDeposits,
+			PendingPartialWithdrawals:     b.pendingPartialWithdrawals,
+			PendingConsolidations:         b.pendingConsolidations,
+			ProposerLookahead:             lookahead,
+		}
 	default:
 		return nil
 	}
@@ -388,7 +433,7 @@ func (b *BeaconState) ToProto() interface{} {
 			NextWithdrawalValidatorIndex: b.nextWithdrawalValidatorIndex,
 			HistoricalSummaries:          b.historicalSummariesVal(),
 		}
-	case version.Electra, version.Fulu:
+	case version.Electra:
 		return &ethpb.BeaconStateElectra{
 			GenesisTime:                   b.genesisTime,
 			GenesisValidatorsRoot:         gvrCopy[:],
@@ -428,6 +473,51 @@ func (b *BeaconState) ToProto() interface{} {
 			PendingPartialWithdrawals:     b.pendingPartialWithdrawalsVal(),
 			PendingConsolidations:         b.pendingConsolidationsVal(),
 		}
+	case version.Fulu:
+		lookahead := make([]uint64, len(b.proposerLookahead))
+		for i, v := range b.proposerLookahead {
+			lookahead[i] = uint64(v)
+		}
+		return &ethpb.BeaconStateFulu{
+			GenesisTime:                   b.genesisTime,
+			GenesisValidatorsRoot:         gvrCopy[:],
+			Slot:                          b.slot,
+			Fork:                          b.forkVal(),
+			LatestBlockHeader:             b.latestBlockHeaderVal(),
+			BlockRoots:                    br,
+			StateRoots:                    sr,
+			HistoricalRoots:               b.historicalRoots.Slice(),
+			Eth1Data:                      b.eth1DataVal(),
+			Eth1DataVotes:                 b.eth1DataVotesVal(),
+			Eth1DepositIndex:              b.eth1DepositIndex,
+			Validators:                    b.validatorsVal(),
+			Balances:                      b.balancesVal(),
+			RandaoMixes:                   rm,
+			Slashings:                     b.slashingsVal(),
+			PreviousEpochParticipation:    b.previousEpochParticipationVal(),
+			CurrentEpochParticipation:     b.currentEpochParticipationVal(),
+			JustificationBits:             b.justificationBitsVal(),
+			PreviousJustifiedCheckpoint:   b.previousJustifiedCheckpointVal(),
+			CurrentJustifiedCheckpoint:    b.currentJustifiedCheckpointVal(),
+			FinalizedCheckpoint:           b.finalizedCheckpointVal(),
+			InactivityScores:              b.inactivityScoresVal(),
+			CurrentSyncCommittee:          b.currentSyncCommitteeVal(),
+			NextSyncCommittee:             b.nextSyncCommitteeVal(),
+			LatestExecutionPayloadHeader:  b.latestExecutionPayloadHeaderDeneb.Copy(),
+			NextWithdrawalIndex:           b.nextWithdrawalIndex,
+			NextWithdrawalValidatorIndex:  b.nextWithdrawalValidatorIndex,
+			HistoricalSummaries:           b.historicalSummariesVal(),
+			DepositRequestsStartIndex:     b.depositRequestsStartIndex,
+			DepositBalanceToConsume:       b.depositBalanceToConsume,
+			ExitBalanceToConsume:          b.exitBalanceToConsume,
+			EarliestExitEpoch:             b.earliestExitEpoch,
+			ConsolidationBalanceToConsume: b.consolidationBalanceToConsume,
+			EarliestConsolidationEpoch:    b.earliestConsolidationEpoch,
+			PendingDeposits:               b.pendingDepositsVal(),
+			PendingPartialWithdrawals:     b.pendingPartialWithdrawalsVal(),
+			PendingConsolidations:         b.pendingConsolidationsVal(),
+			ProposerLookahead:             lookahead,
+		}
 	default:
 		return nil
 	}
@@ -554,4 +644,12 @@ func ProtobufBeaconStateElectra(s interface{}) (*ethpb.BeaconStateElectra, error
 	return pbState, nil
 }
 
-var ProtobufBeaconStateFulu = ProtobufBeaconStateElectra
+// ProtobufBeaconStateFulu transforms an input into beacon state Fulu in the form of protobuf.
+// Error is returned if the input is not type protobuf beacon state.
+func ProtobufBeaconStateFulu(s interface{}) (*ethpb.BeaconStateFulu, error) {
+	pbState, ok := s.(*ethpb.BeaconStateFulu)
+	if !ok {
+		return nil, errors.New("input is not type pb.BeaconStateFulu")
+	}
+	return pbState, nil
+}

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

@@ -320,5 +320,13 @@ func ComputeFieldRootsWithHasher(ctx context.Context, state *BeaconState) ([][]b
 		fieldRoots[types.PendingConsolidations.RealPosition()] = pcRoot[:]
 	}
 
+	if state.version >= version.Fulu {
+		// Proposer lookahead root.
+		proposerLookaheadRoot, err := stateutil.ProposerLookaheadRoot(state.proposerLookahead)
+		if err != nil {
+			return nil, errors.Wrap(err, "could not compute proposer lookahead merkleization")
+		}
+		fieldRoots[types.ProposerLookahead.RealPosition()] = proposerLookaheadRoot[:]
+	}
 	return fieldRoots, nil
 }

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

@@ -0,0 +1,30 @@
+package state_native
+
+import (
+	"errors"
+
+	"github.com/OffchainLabs/prysm/v6/beacon-chain/state/state-native/types"
+	"github.com/OffchainLabs/prysm/v6/beacon-chain/state/stateutil"
+	"github.com/OffchainLabs/prysm/v6/config/params"
+	"github.com/OffchainLabs/prysm/v6/consensus-types/primitives"
+	"github.com/OffchainLabs/prysm/v6/runtime/version"
+)
+
+// SetProposerLookahead is a mutating call to the beacon state which sets the proposer lookahead
+func (b *BeaconState) SetProposerLookahead(lookahead []primitives.ValidatorIndex) error {
+	if b.version < version.Fulu {
+		return errNotSupported("SetProposerLookahead", b.version)
+	}
+	if len(lookahead) != int((params.BeaconConfig().MinSeedLookahead+1))*int(params.BeaconConfig().SlotsPerEpoch) {
+		return errors.New("invalid size for proposer lookahead")
+	}
+	b.lock.Lock()
+	defer b.lock.Unlock()
+	b.sharedFieldReferences[types.ProposerLookahead].MinusRef()
+	b.sharedFieldReferences[types.ProposerLookahead] = stateutil.NewRef(1)
+
+	b.proposerLookahead = lookahead
+
+	b.markFieldAsDirty(types.ProposerLookahead)
+	return nil
+}

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

@@ -14,6 +14,7 @@ import (
 	"github.com/OffchainLabs/prysm/v6/config/features"
 	fieldparams "github.com/OffchainLabs/prysm/v6/config/fieldparams"
 	"github.com/OffchainLabs/prysm/v6/config/params"
+	"github.com/OffchainLabs/prysm/v6/consensus-types/primitives"
 	mvslice "github.com/OffchainLabs/prysm/v6/container/multi-value-slice"
 	"github.com/OffchainLabs/prysm/v6/container/slice"
 	"github.com/OffchainLabs/prysm/v6/encoding/bytesutil"
@@ -108,7 +109,10 @@ var (
 		types.PendingConsolidations,
 	)
 
-	fuluFields = electraFields
+	fuluFields = append(
+		electraFields,
+		types.ProposerLookahead,
+	)
 )
 
 const (
@@ -118,14 +122,14 @@ const (
 	capellaSharedFieldRefCount                    = 13
 	denebSharedFieldRefCount                      = 13
 	electraSharedFieldRefCount                    = 16
-	fuluSharedFieldRefCount                       = 16
+	fuluSharedFieldRefCount                       = 17
 	experimentalStatePhase0SharedFieldRefCount    = 5
 	experimentalStateAltairSharedFieldRefCount    = 5
 	experimentalStateBellatrixSharedFieldRefCount = 6
 	experimentalStateCapellaSharedFieldRefCount   = 7
 	experimentalStateDenebSharedFieldRefCount     = 7
 	experimentalStateElectraSharedFieldRefCount   = 10
-	experimentalStateFuluSharedFieldRefCount      = 10
+	experimentalStateFuluSharedFieldRefCount      = 11
 )
 
 // InitializeFromProtoPhase0 the beacon state from a protobuf representation.
@@ -159,8 +163,8 @@ func InitializeFromProtoElectra(st *ethpb.BeaconStateElectra) (state.BeaconState
 }
 
 // InitializeFromProtoFulu the beacon state from a protobuf representation.
-func InitializeFromProtoFulu(st *ethpb.BeaconStateElectra) (state.BeaconState, error) {
-	return InitializeFromProtoUnsafeFulu(proto.Clone(st).(*ethpb.BeaconStateElectra))
+func InitializeFromProtoFulu(st *ethpb.BeaconStateFulu) (state.BeaconState, error) {
+	return InitializeFromProtoUnsafeFulu(proto.Clone(st).(*ethpb.BeaconStateFulu))
 }
 
 // InitializeFromProtoUnsafePhase0 directly uses the beacon state protobuf fields
@@ -842,7 +846,7 @@ func InitializeFromProtoUnsafeElectra(st *ethpb.BeaconStateElectra) (state.Beaco
 
 // InitializeFromProtoUnsafeFulu directly uses the beacon state protobuf fields
 // and sets them as fields of the BeaconState type.
-func InitializeFromProtoUnsafeFulu(st *ethpb.BeaconStateElectra) (state.BeaconState, error) {
+func InitializeFromProtoUnsafeFulu(st *ethpb.BeaconStateFulu) (state.BeaconState, error) {
 	if st == nil {
 		return nil, errors.New("received nil state")
 	}
@@ -852,6 +856,10 @@ func InitializeFromProtoUnsafeFulu(st *ethpb.BeaconStateElectra) (state.BeaconSt
 		hRoots[i] = bytesutil.ToBytes32(r)
 	}
 
+	proposerLookahead := make([]primitives.ValidatorIndex, len(st.ProposerLookahead))
+	for i, v := range st.ProposerLookahead {
+		proposerLookahead[i] = primitives.ValidatorIndex(v)
+	}
 	fieldCount := params.BeaconConfig().BeaconStateFuluFieldCount
 	b := &BeaconState{
 		version:                           version.Fulu,
@@ -886,6 +894,7 @@ func InitializeFromProtoUnsafeFulu(st *ethpb.BeaconStateElectra) (state.BeaconSt
 		pendingDeposits:                   st.PendingDeposits,
 		pendingPartialWithdrawals:         st.PendingPartialWithdrawals,
 		pendingConsolidations:             st.PendingConsolidations,
+		proposerLookahead:                 proposerLookahead,
 
 		dirtyFields:      make(map[types.FieldIndex]bool, fieldCount),
 		dirtyIndices:     make(map[types.FieldIndex][]uint64, fieldCount),
@@ -950,6 +959,7 @@ func InitializeFromProtoUnsafeFulu(st *ethpb.BeaconStateElectra) (state.BeaconSt
 	b.sharedFieldReferences[types.PendingDeposits] = stateutil.NewRef(1)
 	b.sharedFieldReferences[types.PendingPartialWithdrawals] = stateutil.NewRef(1)
 	b.sharedFieldReferences[types.PendingConsolidations] = stateutil.NewRef(1)
+	b.sharedFieldReferences[types.ProposerLookahead] = stateutil.NewRef(1) // New in Fulu.
 	if !features.Get().EnableExperimentalState {
 		b.sharedFieldReferences[types.BlockRoots] = stateutil.NewRef(1)
 		b.sharedFieldReferences[types.StateRoots] = stateutil.NewRef(1)
@@ -1015,6 +1025,7 @@ func (b *BeaconState) Copy() state.BeaconState {
 		currentEpochAttestations:  b.currentEpochAttestations,
 		eth1DataVotes:             b.eth1DataVotes,
 		slashings:                 b.slashings,
+		proposerLookahead:         b.proposerLookahead,
 
 		// Large arrays, increases over time.
 		balances:                   b.balances,
@@ -1441,6 +1452,8 @@ func (b *BeaconState) rootSelector(ctx context.Context, field types.FieldIndex)
 		return stateutil.PendingPartialWithdrawalsRoot(b.pendingPartialWithdrawals)
 	case types.PendingConsolidations:
 		return stateutil.PendingConsolidationsRoot(b.pendingConsolidations)
+	case types.ProposerLookahead:
+		return stateutil.ProposerLookaheadRoot(b.proposerLookahead)
 	}
 	return [32]byte{}, errors.New("invalid field index provided")
 }

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

@@ -112,6 +112,8 @@ func (f FieldIndex) String() string {
 		return "pendingPartialWithdrawals"
 	case PendingConsolidations:
 		return "pendingConsolidations"
+	case ProposerLookahead:
+		return "proposerLookahead"
 	default:
 		return fmt.Sprintf("unknown field index number: %d", f)
 	}
@@ -195,6 +197,8 @@ func (f FieldIndex) RealPosition() int {
 		return 35
 	case PendingConsolidations:
 		return 36
+	case ProposerLookahead:
+		return 37
 	default:
 		return -1
 	}
@@ -259,6 +263,7 @@ const (
 	PendingDeposits               // Electra: EIP-7251
 	PendingPartialWithdrawals     // Electra: EIP-7251
 	PendingConsolidations         // Electra: EIP-7251
+	ProposerLookahead             // Fulu: EIP 7917
 )
 
 // Enumerator keeps track of the number of states created since the node's start.

beacon-chain/state/stategen/getter.go

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

beacon-chain/state/stategen/service.go

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

beacon-chain/state/stategen/service_test.go

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

beacon-chain/state/stateutil/BUILD.bazel

@@ -15,6 +15,7 @@ go_library(
         "pending_consolidations_root.go",
         "pending_deposits_root.go",
         "pending_partial_withdrawals_root.go",
+        "proposer_lookahead_root.go",
         "reference.go",
         "sync_committee.root.go",
         "trie_helpers.go",
@@ -49,6 +50,7 @@ go_test(
         "benchmark_test.go",
         "field_root_test.go",
         "field_root_validator_test.go",
+        "proposer_lookahead_root_test.go",
         "reference_bench_test.go",
         "state_root_test.go",
         "trie_helpers_test.go",

beacon-chain/state/stateutil/proposer_lookahead_root.go

@@ -0,0 +1,18 @@
+package stateutil
+
+import (
+	"encoding/binary"
+
+	"github.com/OffchainLabs/prysm/v6/consensus-types/primitives"
+	"github.com/OffchainLabs/prysm/v6/encoding/ssz"
+)
+
+// ProposerLookaheadRoot computes the hash tree root of the proposer lookahead
+func ProposerLookaheadRoot(lookahead []primitives.ValidatorIndex) ([32]byte, error) {
+	chunks := make([][32]byte, (len(lookahead)*8+31)/32)
+	for i, idx := range lookahead {
+		j := i / 4
+		binary.LittleEndian.PutUint64(chunks[j][(i%4)*8:], uint64(idx))
+	}
+	return ssz.MerkleizeVector(chunks, uint64(len(chunks))), nil
+}