adding max blobs validation

* Add spec references, a mapping of spec to implementation

* Add changelog fragment

---------

Co-authored-by: james-prysm <90280386+james-prysm@users.noreply.github.com>

.github/workflows/check-specrefs.yml

@@ -0,0 +1,43 @@
+name: Check Spec References
+on: [push, pull_request]
+
+jobs:
+  check-specrefs:
+    runs-on: ubuntu-latest
+
+    steps:
+    - name: Checkout repository
+      uses: actions/checkout@v4
+
+    - name: Check version consistency
+      run: |
+        WORKSPACE_VERSION=$(grep 'consensus_spec_version = ' WORKSPACE | sed 's/.*"\(.*\)"/\1/')
+        ETHSPECIFY_VERSION=$(grep '^version:' specrefs/.ethspecify.yml | sed 's/version: //')
+        if [ "$WORKSPACE_VERSION" != "$ETHSPECIFY_VERSION" ]; then
+          echo "Version mismatch between WORKSPACE and ethspecify"
+          echo "  WORKSPACE: $WORKSPACE_VERSION"
+          echo "  specrefs/.ethspecify.yml: $ETHSPECIFY_VERSION"
+          exit 1
+        else
+          echo "Versions match: $WORKSPACE_VERSION"
+        fi
+
+    - name: Install ethspecify
+      run: python3 -mpip install ethspecify
+
+    - name: Update spec references
+      run: ethspecify process --path=specrefs
+
+    - name: Check for differences
+      run: |
+        if ! git diff --exit-code specrefs >/dev/null; then
+          echo "Spec references are out-of-date!"
+          echo ""
+          git --no-pager diff specrefs
+          exit 1
+        else
+          echo "Spec references are up-to-date!"
+        fi
+
+    - name: Check spec references
+      run: ethspecify check --path=specrefs

WORKSPACE

@@ -253,16 +253,16 @@ filegroup(
     url = "https://github.com/ethereum/EIPs/archive/5480440fe51742ed23342b68cf106cefd427e39d.tar.gz",
 )
 
-consensus_spec_version = "v1.6.0-alpha.1"
+consensus_spec_version = "v1.6.0-alpha.4"
 
 load("@prysm//tools:download_spectests.bzl", "consensus_spec_tests")
 
 consensus_spec_tests(
     name = "consensus_spec_tests",
     flavors = {
-        "general": "sha256-o4t9p3R+fQHF4KOykGmwlG3zDw5wUdVWprkzId8aIsk=",
-        "minimal": "sha256-sU7ToI8t3MR8x0vVjC8ERmAHZDWpEmnAC9FWIpHi5x4=",
-        "mainnet": "sha256-YKS4wngg0LgI9Upp4MYJ77aG+8+e/G4YeqEIlp06LZw=",
+        "general": "sha256-MaN4zu3o0vWZypUHS5r4D8WzJF4wANoadM8qm6iyDs4=",
+        "minimal": "sha256-aZGNPp/bBvJgq3Wf6vyR0H6G3DOkbSuggEmOL4jEmtg=",
+        "mainnet": "sha256-C7jjosvpzUgw3GPajlsWBV02ZbkZ5Uv4ikmOqfDGajI=",
     },
     version = consensus_spec_version,
 )
@@ -278,7 +278,7 @@ filegroup(
     visibility = ["//visibility:public"],
 )
     """,
-    integrity = "sha256-Nv4TEuEJPQIM4E6T9J0FOITsmappmXZjGtlhe1HEXnU=",
+    integrity = "sha256-qreawRS77l8CebiNww8z727qUItw7KlHY1Xqj7IrPdk=",
     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/client/beacon/BUILD.bazel

@@ -16,7 +16,6 @@ go_library(
         "//api/server/structs:go_default_library",
         "//consensus-types/primitives:go_default_library",
         "//encoding/bytesutil:go_default_library",
-        "//network/forks:go_default_library",
         "//proto/prysm/v1alpha1:go_default_library",
         "@com_github_ethereum_go_ethereum//common/hexutil:go_default_library",
         "@com_github_pkg_errors//:go_default_library",

api/client/beacon/client.go

@@ -9,7 +9,6 @@ import (
 	"net/url"
 	"path"
 	"regexp"
-	"sort"
 	"strconv"
 
 	"github.com/OffchainLabs/prysm/v6/api/client"
@@ -17,7 +16,6 @@ import (
 	"github.com/OffchainLabs/prysm/v6/api/server/structs"
 	"github.com/OffchainLabs/prysm/v6/consensus-types/primitives"
 	"github.com/OffchainLabs/prysm/v6/encoding/bytesutil"
-	"github.com/OffchainLabs/prysm/v6/network/forks"
 	ethpb "github.com/OffchainLabs/prysm/v6/proto/prysm/v1alpha1"
 	"github.com/ethereum/go-ethereum/common/hexutil"
 	"github.com/pkg/errors"
@@ -137,24 +135,6 @@ func (c *Client) GetFork(ctx context.Context, stateId StateOrBlockId) (*ethpb.Fo
 	return fr.ToConsensus()
 }
 
-// GetForkSchedule retrieve all forks, past present and future, of which this node is aware.
-func (c *Client) GetForkSchedule(ctx context.Context) (forks.OrderedSchedule, error) {
-	body, err := c.Get(ctx, getForkSchedulePath)
-	if err != nil {
-		return nil, errors.Wrap(err, "error requesting fork schedule")
-	}
-	fsr := &forkScheduleResponse{}
-	err = json.Unmarshal(body, fsr)
-	if err != nil {
-		return nil, err
-	}
-	ofs, err := fsr.OrderedForkSchedule()
-	if err != nil {
-		return nil, errors.Wrap(err, fmt.Sprintf("problem unmarshaling %s response", getForkSchedulePath))
-	}
-	return ofs, nil
-}
-
 // GetConfigSpec retrieve the current configs of the network used by the beacon node.
 func (c *Client) GetConfigSpec(ctx context.Context) (*structs.GetSpecResponse, error) {
 	body, err := c.Get(ctx, getConfigSpecPath)
@@ -334,31 +314,3 @@ func (c *Client) GetBLStoExecutionChanges(ctx context.Context) (*structs.BLSToEx
 	}
 	return poolResponse, nil
 }
-
-type forkScheduleResponse struct {
-	Data []structs.Fork
-}
-
-func (fsr *forkScheduleResponse) OrderedForkSchedule() (forks.OrderedSchedule, error) {
-	ofs := make(forks.OrderedSchedule, 0)
-	for _, d := range fsr.Data {
-		epoch, err := strconv.ParseUint(d.Epoch, 10, 64)
-		if err != nil {
-			return nil, errors.Wrapf(err, "error parsing epoch %s", d.Epoch)
-		}
-		vSlice, err := hexutil.Decode(d.CurrentVersion)
-		if err != nil {
-			return nil, err
-		}
-		if len(vSlice) != 4 {
-			return nil, fmt.Errorf("got %d byte version, expected 4 bytes. version hex=%s", len(vSlice), d.CurrentVersion)
-		}
-		version := bytesutil.ToBytes4(vSlice)
-		ofs = append(ofs, forks.ForkScheduleEntry{
-			Version: version,
-			Epoch:   primitives.Epoch(epoch),
-		})
-	}
-	sort.Sort(ofs)
-	return ofs, nil
-}

api/client/builder/client.go

@@ -102,6 +102,7 @@ type BuilderClient interface {
 	GetHeader(ctx context.Context, slot primitives.Slot, parentHash [32]byte, pubkey [48]byte) (SignedBid, error)
 	RegisterValidator(ctx context.Context, svr []*ethpb.SignedValidatorRegistrationV1) error
 	SubmitBlindedBlock(ctx context.Context, sb interfaces.ReadOnlySignedBeaconBlock) (interfaces.ExecutionData, v1.BlobsBundler, error)
+	SubmitBlindedBlockPostFulu(ctx context.Context, sb interfaces.ReadOnlySignedBeaconBlock) error
 	Status(ctx context.Context) error
 }
 
@@ -152,7 +153,8 @@ func (c *Client) NodeURL() string {
 type reqOption func(*http.Request)
 
 // do is a generic, opinionated request function to reduce boilerplate amongst the methods in this package api/client/builder.
-func (c *Client) do(ctx context.Context, method string, path string, body io.Reader, opts ...reqOption) (res []byte, header http.Header, err error) {
+// It validates that the HTTP response status matches the expectedStatus parameter.
+func (c *Client) do(ctx context.Context, method string, path string, body io.Reader, expectedStatus int, opts ...reqOption) (res []byte, header http.Header, err error) {
 	ctx, span := trace.StartSpan(ctx, "builder.client.do")
 	defer func() {
 		tracing.AnnotateError(span, err)
@@ -187,8 +189,8 @@ func (c *Client) do(ctx context.Context, method string, path string, body io.Rea
 			log.WithError(closeErr).Error("Failed to close response body")
 		}
 	}()
-	if r.StatusCode != http.StatusOK {
-		err = non200Err(r)
+	if r.StatusCode != expectedStatus {
+		err = unexpectedStatusErr(r, expectedStatus)
 		return
 	}
 	res, err = io.ReadAll(io.LimitReader(r.Body, client.MaxBodySize))
@@ -236,7 +238,7 @@ func (c *Client) GetHeader(ctx context.Context, slot primitives.Slot, parentHash
 			r.Header.Set("Accept", api.JsonMediaType)
 		}
 	}
-	data, header, err := c.do(ctx, http.MethodGet, path, nil, getOpts)
+	data, header, err := c.do(ctx, http.MethodGet, path, nil, http.StatusOK, getOpts)
 	if err != nil {
 		return nil, errors.Wrap(err, "error getting header from builder server")
 	}
@@ -409,7 +411,7 @@ func (c *Client) RegisterValidator(ctx context.Context, svr []*ethpb.SignedValid
 		}
 	}
 
-	if _, _, err = c.do(ctx, http.MethodPost, postRegisterValidatorPath, bytes.NewBuffer(body), postOpts); err != nil {
+	if _, _, err = c.do(ctx, http.MethodPost, postRegisterValidatorPath, bytes.NewBuffer(body), http.StatusOK, postOpts); err != nil {
 		return errors.Wrap(err, "do")
 	}
 	log.WithField("registrationCount", len(svr)).Debug("Successfully registered validator(s) on builder")
@@ -471,7 +473,7 @@ func (c *Client) SubmitBlindedBlock(ctx context.Context, sb interfaces.ReadOnlyS
 
 	// post the blinded block - the execution payload response should contain the unblinded payload, along with the
 	// blobs bundle if it is post deneb.
-	data, header, err := c.do(ctx, http.MethodPost, postBlindedBeaconBlockPath, bytes.NewBuffer(body), postOpts)
+	data, header, err := c.do(ctx, http.MethodPost, postBlindedBeaconBlockPath, bytes.NewBuffer(body), http.StatusOK, postOpts)
 	if err != nil {
 		return nil, nil, errors.Wrap(err, "error posting the blinded block to the builder api")
 	}
@@ -501,6 +503,24 @@ func (c *Client) SubmitBlindedBlock(ctx context.Context, sb interfaces.ReadOnlyS
 	return ed, blobs, nil
 }
 
+// SubmitBlindedBlockPostFulu calls the builder API endpoint post-Fulu where relays only return status codes.
+// This method is used after the Fulu fork when MEV-boost relays no longer return execution payloads.
+func (c *Client) SubmitBlindedBlockPostFulu(ctx context.Context, sb interfaces.ReadOnlySignedBeaconBlock) error {
+	body, postOpts, err := c.buildBlindedBlockRequest(sb)
+	if err != nil {
+		return err
+	}
+
+	// Post the blinded block - the response should only contain a status code (no payload)
+	_, _, err = c.do(ctx, http.MethodPost, postBlindedBeaconBlockPath, bytes.NewBuffer(body), http.StatusAccepted, postOpts)
+	if err != nil {
+		return errors.Wrap(err, "error posting the blinded block to the builder api post-Fulu")
+	}
+
+	// Success is indicated by no error (status 202)
+	return nil
+}
+
 func (c *Client) checkBlockVersion(respBytes []byte, header http.Header) (int, error) {
 	var versionHeader string
 	if c.sszEnabled {
@@ -657,11 +677,11 @@ func (c *Client) Status(ctx context.Context) error {
 	getOpts := func(r *http.Request) {
 		r.Header.Set("Accept", api.JsonMediaType)
 	}
-	_, _, err := c.do(ctx, http.MethodGet, getStatus, nil, getOpts)
+	_, _, err := c.do(ctx, http.MethodGet, getStatus, nil, http.StatusOK, getOpts)
 	return err
 }
 
-func non200Err(response *http.Response) error {
+func unexpectedStatusErr(response *http.Response, expected int) error {
 	bodyBytes, err := io.ReadAll(io.LimitReader(response.Body, client.MaxErrBodySize))
 	var errMessage ErrorMessage
 	var body string
@@ -670,7 +690,7 @@ func non200Err(response *http.Response) error {
 	} else {
 		body = "response body:\n" + string(bodyBytes)
 	}
-	msg := fmt.Sprintf("code=%d, url=%s, body=%s", response.StatusCode, response.Request.URL, body)
+	msg := fmt.Sprintf("expected=%d, got=%d, url=%s, body=%s", expected, response.StatusCode, response.Request.URL, body)
 	switch response.StatusCode {
 	case http.StatusUnsupportedMediaType:
 		log.WithError(ErrUnsupportedMediaType).Debug(msg)

api/client/builder/client_test.go

@@ -1555,6 +1555,89 @@ func testSignedBlindedBeaconBlockElectra(t *testing.T) *eth.SignedBlindedBeaconB
 	}
 }
 
+func TestSubmitBlindedBlockPostFulu(t *testing.T) {
+	ctx := t.Context()
+
+	t.Run("success", func(t *testing.T) {
+		hc := &http.Client{
+			Transport: roundtrip(func(r *http.Request) (*http.Response, error) {
+				require.Equal(t, postBlindedBeaconBlockPath, r.URL.Path)
+				require.Equal(t, "bellatrix", r.Header.Get("Eth-Consensus-Version"))
+				require.Equal(t, api.JsonMediaType, r.Header.Get("Content-Type"))
+				require.Equal(t, api.JsonMediaType, r.Header.Get("Accept"))
+				// Post-Fulu: only return status code, no payload
+				return &http.Response{
+					StatusCode: http.StatusAccepted,
+					Body:       io.NopCloser(bytes.NewBufferString("")),
+					Request:    r.Clone(ctx),
+				}, nil
+			}),
+		}
+		c := &Client{
+			hc:      hc,
+			baseURL: &url.URL{Host: "localhost:3500", Scheme: "http"},
+		}
+		sbbb, err := blocks.NewSignedBeaconBlock(testSignedBlindedBeaconBlockBellatrix(t))
+		require.NoError(t, err)
+		err = c.SubmitBlindedBlockPostFulu(ctx, sbbb)
+		require.NoError(t, err)
+	})
+
+	t.Run("success_ssz", func(t *testing.T) {
+		hc := &http.Client{
+			Transport: roundtrip(func(r *http.Request) (*http.Response, error) {
+				require.Equal(t, postBlindedBeaconBlockPath, r.URL.Path)
+				require.Equal(t, "bellatrix", r.Header.Get(api.VersionHeader))
+				require.Equal(t, api.OctetStreamMediaType, r.Header.Get("Content-Type"))
+				require.Equal(t, api.OctetStreamMediaType, r.Header.Get("Accept"))
+				// Post-Fulu: only return status code, no payload
+				return &http.Response{
+					StatusCode: http.StatusAccepted,
+					Body:       io.NopCloser(bytes.NewBufferString("")),
+					Request:    r.Clone(ctx),
+				}, nil
+			}),
+		}
+		c := &Client{
+			hc:         hc,
+			baseURL:    &url.URL{Host: "localhost:3500", Scheme: "http"},
+			sszEnabled: true,
+		}
+		sbbb, err := blocks.NewSignedBeaconBlock(testSignedBlindedBeaconBlockBellatrix(t))
+		require.NoError(t, err)
+		err = c.SubmitBlindedBlockPostFulu(ctx, sbbb)
+		require.NoError(t, err)
+	})
+
+	t.Run("error_response", func(t *testing.T) {
+		hc := &http.Client{
+			Transport: roundtrip(func(r *http.Request) (*http.Response, error) {
+				require.Equal(t, postBlindedBeaconBlockPath, r.URL.Path)
+				require.Equal(t, "bellatrix", r.Header.Get("Eth-Consensus-Version"))
+				message := ErrorMessage{
+					Code:    400,
+					Message: "Bad Request",
+				}
+				resp, err := json.Marshal(message)
+				require.NoError(t, err)
+				return &http.Response{
+					StatusCode: http.StatusBadRequest,
+					Body:       io.NopCloser(bytes.NewBuffer(resp)),
+					Request:    r.Clone(ctx),
+				}, nil
+			}),
+		}
+		c := &Client{
+			hc:      hc,
+			baseURL: &url.URL{Host: "localhost:3500", Scheme: "http"},
+		}
+		sbbb, err := blocks.NewSignedBeaconBlock(testSignedBlindedBeaconBlockBellatrix(t))
+		require.NoError(t, err)
+		err = c.SubmitBlindedBlockPostFulu(ctx, sbbb)
+		require.ErrorIs(t, err, ErrNotOK)
+	})
+}
+
 func TestRequestLogger(t *testing.T) {
 	wo := WithObserver(&requestLogger{})
 	c, err := NewClient("localhost:3500", wo)
@@ -1727,7 +1810,7 @@ func TestSubmitBlindedBlock_BlobsBundlerInterface(t *testing.T) {
 	t.Run("Interface signature verification", func(t *testing.T) {
 		// This test verifies that the SubmitBlindedBlock method signature
 		// has been updated to return BlobsBundler interface
-		
+
 		client := &Client{}
 
 		// Verify the method exists with the correct signature

api/client/builder/testing/mock.go

@@ -45,6 +45,11 @@ func (MockClient) SubmitBlindedBlock(_ context.Context, _ interfaces.ReadOnlySig
 	return nil, nil, nil
 }
 
+// SubmitBlindedBlockPostFulu --
+func (MockClient) SubmitBlindedBlockPostFulu(_ context.Context, _ interfaces.ReadOnlySignedBeaconBlock) error {
+	return nil
+}
+
 // Status --
 func (MockClient) Status(_ context.Context) error {
 	return nil

api/client/builder/types_test.go

@@ -1699,7 +1699,7 @@ func TestExecutionPayloadHeaderCapellaRoundtrip(t *testing.T) {
 	require.DeepEqual(t, string(expected[0:len(expected)-1]), string(m))
 }
 
-func TestErrorMessage_non200Err(t *testing.T) {
+func TestErrorMessage_unexpectedStatusErr(t *testing.T) {
 	mockRequest := &http.Request{
 		URL: &url.URL{Path: "example.com"},
 	}
@@ -1779,7 +1779,7 @@ func TestErrorMessage_non200Err(t *testing.T) {
 	}
 	for _, tt := range tests {
 		t.Run(tt.name, func(t *testing.T) {
-			err := non200Err(tt.args)
+			err := unexpectedStatusErr(tt.args, http.StatusOK)
 			if err != nil && tt.wantMessage != "" {
 				require.ErrorContains(t, tt.wantMessage, err)
 			}

beacon-chain/blockchain/kzg/validation.go

@@ -6,20 +6,20 @@ import (
 )
 
 // Verify performs single or batch verification of commitments depending on the number of given BlobSidecars.
-func Verify(sidecars ...blocks.ROBlob) error {
-	if len(sidecars) == 0 {
+func Verify(blobSidecars ...blocks.ROBlob) error {
+	if len(blobSidecars) == 0 {
 		return nil
 	}
-	if len(sidecars) == 1 {
+	if len(blobSidecars) == 1 {
 		return kzgContext.VerifyBlobKZGProof(
-			bytesToBlob(sidecars[0].Blob),
-			bytesToCommitment(sidecars[0].KzgCommitment),
-			bytesToKZGProof(sidecars[0].KzgProof))
+			bytesToBlob(blobSidecars[0].Blob),
+			bytesToCommitment(blobSidecars[0].KzgCommitment),
+			bytesToKZGProof(blobSidecars[0].KzgProof))
 	}
-	blobs := make([]GoKZG.Blob, len(sidecars))
-	cmts := make([]GoKZG.KZGCommitment, len(sidecars))
-	proofs := make([]GoKZG.KZGProof, len(sidecars))
-	for i, sidecar := range sidecars {
+	blobs := make([]GoKZG.Blob, len(blobSidecars))
+	cmts := make([]GoKZG.KZGCommitment, len(blobSidecars))
+	proofs := make([]GoKZG.KZGProof, len(blobSidecars))
+	for i, sidecar := range blobSidecars {
 		blobs[i] = *bytesToBlob(sidecar.Blob)
 		cmts[i] = bytesToCommitment(sidecar.KzgCommitment)
 		proofs[i] = bytesToKZGProof(sidecar.KzgProof)

beacon-chain/blockchain/kzg/validation_test.go

@@ -22,8 +22,8 @@ func GenerateCommitmentAndProof(blob GoKZG.Blob) (GoKZG.KZGCommitment, GoKZG.KZG
 }
 
 func TestVerify(t *testing.T) {
-	sidecars := make([]blocks.ROBlob, 0)
-	require.NoError(t, Verify(sidecars...))
+	blobSidecars := make([]blocks.ROBlob, 0)
+	require.NoError(t, Verify(blobSidecars...))
 }
 
 func TestBytesToAny(t *testing.T) {

beacon-chain/blockchain/process_block.go

@@ -240,9 +240,10 @@ func (s *Service) onBlockBatch(ctx context.Context, blks []consensusblocks.ROBlo
 			}
 		}
 
-		if err := avs.IsDataAvailable(ctx, s.CurrentSlot(), b); err != nil {
-			return errors.Wrapf(err, "could not validate sidecar availability at slot %d", b.Block().Slot())
+		if err := s.areSidecarsAvailable(ctx, avs, b); err != nil {
+			return errors.Wrapf(err, "could not validate sidecar availability for block %#x at slot %d", b.Root(), b.Block().Slot())
 		}
+
 		args := &forkchoicetypes.BlockAndCheckpoints{Block: b,
 			JustifiedCheckpoint: jCheckpoints[i],
 			FinalizedCheckpoint: fCheckpoints[i]}
@@ -308,6 +309,30 @@ func (s *Service) onBlockBatch(ctx context.Context, blks []consensusblocks.ROBlo
 	return s.saveHeadNoDB(ctx, lastB, lastBR, preState, !isValidPayload)
 }
 
+func (s *Service) areSidecarsAvailable(ctx context.Context, avs das.AvailabilityStore, roBlock consensusblocks.ROBlock) error {
+	blockVersion := roBlock.Version()
+	block := roBlock.Block()
+	slot := block.Slot()
+
+	if blockVersion >= version.Fulu {
+		if err := s.areDataColumnsAvailable(ctx, roBlock.Root(), block); err != nil {
+			return errors.Wrapf(err, "are data columns available for block %#x with slot %d", roBlock.Root(), slot)
+		}
+
+		return nil
+	}
+
+	if blockVersion >= version.Deneb {
+		if err := avs.IsDataAvailable(ctx, s.CurrentSlot(), roBlock); err != nil {
+			return errors.Wrapf(err, "could not validate sidecar availability at slot %d", slot)
+		}
+
+		return nil
+	}
+
+	return nil
+}
+
 func (s *Service) updateEpochBoundaryCaches(ctx context.Context, st state.BeaconState) error {
 	e := coreTime.CurrentEpoch(st)
 	if err := helpers.UpdateCommitteeCache(ctx, st, e); err != nil {
@@ -584,7 +609,7 @@ func (s *Service) runLateBlockTasks() {
 // It returns a map where each key represents a missing BlobSidecar index.
 // An empty map means we have all indices; a non-empty map can be used to compare incoming
 // BlobSidecars against the set of known missing sidecars.
-func missingBlobIndices(bs *filesystem.BlobStorage, root [fieldparams.RootLength]byte, expected [][]byte, slot primitives.Slot) (map[uint64]bool, error) {
+func missingBlobIndices(store *filesystem.BlobStorage, root [fieldparams.RootLength]byte, expected [][]byte, slot primitives.Slot) (map[uint64]bool, error) {
 	maxBlobsPerBlock := params.BeaconConfig().MaxBlobsPerBlock(slot)
 	if len(expected) == 0 {
 		return nil, nil
@@ -592,7 +617,7 @@ func missingBlobIndices(bs *filesystem.BlobStorage, root [fieldparams.RootLength
 	if len(expected) > maxBlobsPerBlock {
 		return nil, errMaxBlobsExceeded
 	}
-	indices := bs.Summary(root)
+	indices := store.Summary(root)
 	missing := make(map[uint64]bool, len(expected))
 	for i := range expected {
 		if len(expected[i]) > 0 && !indices.HasIndex(uint64(i)) {
@@ -607,7 +632,7 @@ func missingBlobIndices(bs *filesystem.BlobStorage, root [fieldparams.RootLength
 // It returns a map where each key represents a missing DataColumnSidecar index.
 // An empty map means we have all indices; a non-empty map can be used to compare incoming
 // DataColumns against the set of known missing sidecars.
-func missingDataColumnIndices(bs *filesystem.DataColumnStorage, root [fieldparams.RootLength]byte, expected map[uint64]bool) (map[uint64]bool, error) {
+func missingDataColumnIndices(store *filesystem.DataColumnStorage, root [fieldparams.RootLength]byte, expected map[uint64]bool) (map[uint64]bool, error) {
 	if len(expected) == 0 {
 		return nil, nil
 	}
@@ -619,7 +644,7 @@ func missingDataColumnIndices(bs *filesystem.DataColumnStorage, root [fieldparam
 	}
 
 	// Get a summary of the data columns stored in the database.
-	summary := bs.Summary(root)
+	summary := store.Summary(root)
 
 	// Check all expected data columns against the summary.
 	missing := make(map[uint64]bool)
@@ -717,7 +742,7 @@ func (s *Service) areDataColumnsAvailable(
 	summary := s.dataColumnStorage.Summary(root)
 	storedDataColumnsCount := summary.Count()
 
-	minimumColumnCountToReconstruct := peerdas.MinimumColumnsCountToReconstruct()
+	minimumColumnCountToReconstruct := peerdas.MinimumColumnCountToReconstruct()
 
 	// As soon as we have enough data column sidecars, we can reconstruct the missing ones.
 	// We don't need to wait for the rest of the data columns to declare the block as available.
@@ -820,7 +845,7 @@ func (s *Service) areDataColumnsAvailable(
 				missingIndices = uint64MapToSortedSlice(missingMap)
 			}
 
-			return errors.Wrapf(ctx.Err(), "data column sidecars slot: %d, BlockRoot: %#x, missing %v", block.Slot(), root, missingIndices)
+			return errors.Wrapf(ctx.Err(), "data column sidecars slot: %d, BlockRoot: %#x, missing: %v", block.Slot(), root, missingIndices)
 		}
 	}
 }

beacon-chain/blockchain/process_block_test.go

@@ -2889,7 +2889,7 @@ func TestIsDataAvailable(t *testing.T) {
 	})
 
 	t.Run("Fulu - more than half of the columns in custody", func(t *testing.T) {
-		minimumColumnsCountToReconstruct := peerdas.MinimumColumnsCountToReconstruct()
+		minimumColumnsCountToReconstruct := peerdas.MinimumColumnCountToReconstruct()
 		indices := make([]uint64, 0, minimumColumnsCountToReconstruct)
 		for i := range minimumColumnsCountToReconstruct {
 			indices = append(indices, i)
@@ -2974,7 +2974,7 @@ func TestIsDataAvailable(t *testing.T) {
 
 		startWaiting := make(chan bool)
 
-		minimumColumnsCountToReconstruct := peerdas.MinimumColumnsCountToReconstruct()
+		minimumColumnsCountToReconstruct := peerdas.MinimumColumnCountToReconstruct()
 		indices := make([]uint64, 0, minimumColumnsCountToReconstruct-missingColumns)
 
 		for i := range minimumColumnsCountToReconstruct - missingColumns {

beacon-chain/blockchain/receive_data_column.go

@@ -17,7 +17,7 @@ func (s *Service) ReceiveDataColumns(dataColumnSidecars []blocks.VerifiedRODataC
 // ReceiveDataColumn receives a single data column.
 func (s *Service) ReceiveDataColumn(dataColumnSidecar blocks.VerifiedRODataColumn) error {
 	if err := s.dataColumnStorage.Save([]blocks.VerifiedRODataColumn{dataColumnSidecar}); err != nil {
-		return errors.Wrap(err, "save data column sidecars")
+		return errors.Wrap(err, "save data column sidecar")
 	}
 
 	return nil

beacon-chain/blockchain/setup_test.go

@@ -89,7 +89,7 @@ func (mb *mockBroadcaster) BroadcastLightClientFinalityUpdate(_ context.Context,
 	return nil
 }
 
-func (mb *mockBroadcaster) BroadcastDataColumn(_ [fieldparams.RootLength]byte, _ uint64, _ *ethpb.DataColumnSidecar) error {
+func (mb *mockBroadcaster) BroadcastDataColumnSidecar(_ [fieldparams.RootLength]byte, _ uint64, _ *ethpb.DataColumnSidecar) error {
 	mb.broadcastCalled = true
 	return nil
 }

beacon-chain/builder/service.go

@@ -25,6 +25,7 @@ var ErrNoBuilder = errors.New("builder endpoint not configured")
 // BlockBuilder defines the interface for interacting with the block builder
 type BlockBuilder interface {
 	SubmitBlindedBlock(ctx context.Context, block interfaces.ReadOnlySignedBeaconBlock) (interfaces.ExecutionData, v1.BlobsBundler, error)
+	SubmitBlindedBlockPostFulu(ctx context.Context, block interfaces.ReadOnlySignedBeaconBlock) error
 	GetHeader(ctx context.Context, slot primitives.Slot, parentHash [32]byte, pubKey [48]byte) (builder.SignedBid, error)
 	RegisterValidator(ctx context.Context, reg []*ethpb.SignedValidatorRegistrationV1) error
 	RegistrationByValidatorID(ctx context.Context, id primitives.ValidatorIndex) (*ethpb.ValidatorRegistrationV1, error)
@@ -101,6 +102,22 @@ func (s *Service) SubmitBlindedBlock(ctx context.Context, b interfaces.ReadOnlyS
 	return s.c.SubmitBlindedBlock(ctx, b)
 }
 
+// SubmitBlindedBlockPostFulu submits a blinded block to the builder relay network post-Fulu.
+// After Fulu, relays only return status codes (no payload).
+func (s *Service) SubmitBlindedBlockPostFulu(ctx context.Context, b interfaces.ReadOnlySignedBeaconBlock) error {
+	ctx, span := trace.StartSpan(ctx, "builder.SubmitBlindedBlockPostFulu")
+	defer span.End()
+	start := time.Now()
+	defer func() {
+		submitBlindedBlockLatency.Observe(float64(time.Since(start).Milliseconds()))
+	}()
+	if s.c == nil {
+		return ErrNoBuilder
+	}
+
+	return s.c.SubmitBlindedBlockPostFulu(ctx, b)
+}
+
 // GetHeader retrieves the header for a given slot and parent hash from the builder relay network.
 func (s *Service) GetHeader(ctx context.Context, slot primitives.Slot, parentHash [32]byte, pubKey [48]byte) (builder.SignedBid, error) {
 	ctx, span := trace.StartSpan(ctx, "builder.GetHeader")

beacon-chain/builder/testing/mock.go

@@ -24,21 +24,22 @@ type Config struct {
 
 // MockBuilderService to mock builder.
 type MockBuilderService struct {
-	HasConfigured         bool
-	Payload               *v1.ExecutionPayload
-	PayloadCapella        *v1.ExecutionPayloadCapella
-	PayloadDeneb          *v1.ExecutionPayloadDeneb
-	BlobBundle            *v1.BlobsBundle
-	BlobBundleV2          *v1.BlobsBundleV2
-	ErrSubmitBlindedBlock error
-	Bid                   *ethpb.SignedBuilderBid
-	BidCapella            *ethpb.SignedBuilderBidCapella
-	BidDeneb              *ethpb.SignedBuilderBidDeneb
-	BidElectra            *ethpb.SignedBuilderBidElectra
-	RegistrationCache     *cache.RegistrationCache
-	ErrGetHeader          error
-	ErrRegisterValidator  error
-	Cfg                   *Config
+	HasConfigured                 bool
+	Payload                       *v1.ExecutionPayload
+	PayloadCapella                *v1.ExecutionPayloadCapella
+	PayloadDeneb                  *v1.ExecutionPayloadDeneb
+	BlobBundle                    *v1.BlobsBundle
+	BlobBundleV2                  *v1.BlobsBundleV2
+	ErrSubmitBlindedBlock         error
+	ErrSubmitBlindedBlockPostFulu error
+	Bid                           *ethpb.SignedBuilderBid
+	BidCapella                    *ethpb.SignedBuilderBidCapella
+	BidDeneb                      *ethpb.SignedBuilderBidDeneb
+	BidElectra                    *ethpb.SignedBuilderBidElectra
+	RegistrationCache             *cache.RegistrationCache
+	ErrGetHeader                  error
+	ErrRegisterValidator          error
+	Cfg                           *Config
 }
 
 // Configured for mocking.
@@ -115,3 +116,8 @@ func (s *MockBuilderService) RegistrationByValidatorID(ctx context.Context, id p
 func (s *MockBuilderService) RegisterValidator(context.Context, []*ethpb.SignedValidatorRegistrationV1) error {
 	return s.ErrRegisterValidator
 }
+
+// SubmitBlindedBlockPostFulu for mocking.
+func (s *MockBuilderService) SubmitBlindedBlockPostFulu(_ context.Context, _ interfaces.ReadOnlySignedBeaconBlock) error {
+	return s.ErrSubmitBlindedBlockPostFulu
+}

beacon-chain/core/blocks/BUILD.bazel

@@ -41,7 +41,6 @@ go_library(
         "//encoding/ssz:go_default_library",
         "//math:go_default_library",
         "//monitoring/tracing/trace:go_default_library",
-        "//network/forks:go_default_library",
         "//proto/engine/v1:go_default_library",
         "//proto/prysm/v1alpha1:go_default_library",
         "//proto/prysm/v1alpha1/attestation:go_default_library",

beacon-chain/core/blocks/signature.go

@@ -11,7 +11,6 @@ import (
 	"github.com/OffchainLabs/prysm/v6/consensus-types/interfaces"
 	"github.com/OffchainLabs/prysm/v6/consensus-types/primitives"
 	"github.com/OffchainLabs/prysm/v6/crypto/bls"
-	"github.com/OffchainLabs/prysm/v6/network/forks"
 	ethpb "github.com/OffchainLabs/prysm/v6/proto/prysm/v1alpha1"
 	"github.com/OffchainLabs/prysm/v6/proto/prysm/v1alpha1/attestation"
 	"github.com/OffchainLabs/prysm/v6/time/slots"
@@ -101,7 +100,7 @@ func VerifyBlockHeaderSignature(beaconState state.BeaconState, header *ethpb.Sig
 // via the respective epoch.
 func VerifyBlockSignatureUsingCurrentFork(beaconState state.ReadOnlyBeaconState, blk interfaces.ReadOnlySignedBeaconBlock, blkRoot [32]byte) error {
 	currentEpoch := slots.ToEpoch(blk.Block().Slot())
-	fork, err := forks.Fork(currentEpoch)
+	fork, err := params.Fork(currentEpoch)
 	if err != nil {
 		return err
 	}

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/peerdas/das_core.go

@@ -223,6 +223,14 @@ func dataColumnsSidecars(
 			cellsForRow := cellsAndProofs[rowIndex].Cells
 			proofsForRow := cellsAndProofs[rowIndex].Proofs
 
+			// Validate that we have enough cells and proofs for this column index
+			if columnIndex >= uint64(len(cellsForRow)) {
+				return nil, errors.Errorf("column index %d exceeds cells length %d for blob %d", columnIndex, len(cellsForRow), rowIndex)
+			}
+			if columnIndex >= uint64(len(proofsForRow)) {
+				return nil, errors.Errorf("column index %d exceeds proofs length %d for blob %d", columnIndex, len(proofsForRow), rowIndex)
+			}
+
 			cell := cellsForRow[columnIndex]
 			column = append(column, cell)
 

beacon-chain/core/peerdas/das_core_test.go

@@ -67,6 +67,55 @@ func TestDataColumnSidecars(t *testing.T) {
 		_, err = peerdas.DataColumnSidecars(signedBeaconBlock, cellsAndProofs)
 		require.ErrorIs(t, err, peerdas.ErrSizeMismatch)
 	})
+
+	t.Run("cells array too short for column index", func(t *testing.T) {
+		// Create a Fulu block with a blob commitment.
+		signedBeaconBlockPb := util.NewBeaconBlockFulu()
+		signedBeaconBlockPb.Block.Body.BlobKzgCommitments = [][]byte{make([]byte, 48)}
+
+		// Create a signed beacon block from the protobuf.
+		signedBeaconBlock, err := blocks.NewSignedBeaconBlock(signedBeaconBlockPb)
+		require.NoError(t, err)
+
+		// Create cells and proofs with insufficient cells for the number of columns.
+		// This simulates a scenario where cellsAndProofs has fewer cells than expected columns.
+		cellsAndProofs := []kzg.CellsAndProofs{
+			{
+				Cells:  make([]kzg.Cell, 10),  // Only 10 cells
+				Proofs: make([]kzg.Proof, 10), // Only 10 proofs
+			},
+		}
+
+		// This should fail because the function will try to access columns up to NumberOfColumns
+		// but we only have 10 cells/proofs.
+		_, err = peerdas.DataColumnSidecars(signedBeaconBlock, cellsAndProofs)
+		require.ErrorContains(t, "column index", err)
+		require.ErrorContains(t, "exceeds cells length", err)
+	})
+
+	t.Run("proofs array too short for column index", func(t *testing.T) {
+		// Create a Fulu block with a blob commitment.
+		signedBeaconBlockPb := util.NewBeaconBlockFulu()
+		signedBeaconBlockPb.Block.Body.BlobKzgCommitments = [][]byte{make([]byte, 48)}
+
+		// Create a signed beacon block from the protobuf.
+		signedBeaconBlock, err := blocks.NewSignedBeaconBlock(signedBeaconBlockPb)
+		require.NoError(t, err)
+
+		// Create cells and proofs with sufficient cells but insufficient proofs.
+		numberOfColumns := params.BeaconConfig().NumberOfColumns
+		cellsAndProofs := []kzg.CellsAndProofs{
+			{
+				Cells:  make([]kzg.Cell, numberOfColumns),
+				Proofs: make([]kzg.Proof, 5), // Only 5 proofs, less than columns
+			},
+		}
+
+		// This should fail when trying to access proof beyond index 4.
+		_, err = peerdas.DataColumnSidecars(signedBeaconBlock, cellsAndProofs)
+		require.ErrorContains(t, "column index", err)
+		require.ErrorContains(t, "exceeds proofs length", err)
+	})
 }
 
 func TestComputeCustodyGroupForColumn(t *testing.T) {

beacon-chain/core/peerdas/reconstruction.go

@@ -18,8 +18,8 @@ var (
 	ErrBlobsCellsProofsMismatch = errors.New("blobs and cells proofs mismatch")
 )
 
-// MinimumColumnsCountToReconstruct return the minimum number of columns needed to proceed to a reconstruction.
-func MinimumColumnsCountToReconstruct() uint64 {
+// MinimumColumnCountToReconstruct return the minimum number of columns needed to proceed to a reconstruction.
+func MinimumColumnCountToReconstruct() uint64 {
 	// If the number of columns is odd, then we need total / 2 + 1 columns to reconstruct.
 	// If the number of columns is even, then we need total / 2 columns to reconstruct.
 	return (params.BeaconConfig().NumberOfColumns + 1) / 2
@@ -58,7 +58,7 @@ func ReconstructDataColumnSidecars(inVerifiedRoSidecars []blocks.VerifiedRODataC
 
 	// Check if there is enough sidecars to reconstruct the missing columns.
 	sidecarCount := len(sidecarByIndex)
-	if uint64(sidecarCount) < MinimumColumnsCountToReconstruct() {
+	if uint64(sidecarCount) < MinimumColumnCountToReconstruct() {
 		return nil, ErrNotEnoughDataColumnSidecars
 	}
 

beacon-chain/core/peerdas/reconstruction_test.go

@@ -48,7 +48,7 @@ func TestMinimumColumnsCountToReconstruct(t *testing.T) {
 			params.OverrideBeaconConfig(cfg)
 
 			// Compute the minimum number of columns needed to reconstruct.
-			actual := peerdas.MinimumColumnsCountToReconstruct()
+			actual := peerdas.MinimumColumnCountToReconstruct()
 			require.Equal(t, tc.expected, actual)
 		})
 	}
@@ -100,7 +100,7 @@ func TestReconstructDataColumnSidecars(t *testing.T) {
 	t.Run("not enough columns to enable reconstruction", func(t *testing.T) {
 		_, _, verifiedRoSidecars := util.GenerateTestFuluBlockWithSidecars(t, 3)
 
-		minimum := peerdas.MinimumColumnsCountToReconstruct()
+		minimum := peerdas.MinimumColumnCountToReconstruct()
 		_, err := peerdas.ReconstructDataColumnSidecars(verifiedRoSidecars[:minimum-1])
 		require.ErrorIs(t, err, peerdas.ErrNotEnoughDataColumnSidecars)
 	})

beacon-chain/core/signing/BUILD.bazel

@@ -4,7 +4,6 @@ go_library(
     name = "go_default_library",
     srcs = [
         "domain.go",
-        "signature.go",
         "signing_root.go",
     ],
     importpath = "github.com/OffchainLabs/prysm/v6/beacon-chain/core/signing",
@@ -25,7 +24,6 @@ go_test(
     name = "go_default_test",
     srcs = [
         "domain_test.go",
-        "signature_test.go",
         "signing_root_test.go",
     ],
     embed = [":go_default_library"],

beacon-chain/core/signing/signature.go

@@ -1,34 +0,0 @@
-package signing
-
-import (
-	"github.com/OffchainLabs/prysm/v6/config/params"
-	ethpb "github.com/OffchainLabs/prysm/v6/proto/prysm/v1alpha1"
-	"github.com/pkg/errors"
-)
-
-var ErrNilRegistration = errors.New("nil signed registration")
-
-// VerifyRegistrationSignature verifies the signature of a validator's registration.
-func VerifyRegistrationSignature(
-	sr *ethpb.SignedValidatorRegistrationV1,
-) error {
-	if sr == nil || sr.Message == nil {
-		return ErrNilRegistration
-	}
-
-	d := params.BeaconConfig().DomainApplicationBuilder
-	// Per spec, we want the fork version and genesis validator to be nil.
-	// Which is genesis value and zero by default.
-	sd, err := ComputeDomain(
-		d,
-		nil, /* fork version */
-		nil /* genesis val root */)
-	if err != nil {
-		return err
-	}
-
-	if err := VerifySigningRoot(sr.Message, sr.Message.Pubkey, sr.Signature, sd); err != nil {
-		return ErrSigFailedToVerify
-	}
-	return nil
-}

beacon-chain/core/signing/signature_test.go

@@ -1,42 +0,0 @@
-package signing_test
-
-import (
-	"testing"
-	"time"
-
-	"github.com/OffchainLabs/prysm/v6/beacon-chain/core/signing"
-	"github.com/OffchainLabs/prysm/v6/config/params"
-	"github.com/OffchainLabs/prysm/v6/crypto/bls"
-	"github.com/OffchainLabs/prysm/v6/encoding/bytesutil"
-	ethpb "github.com/OffchainLabs/prysm/v6/proto/prysm/v1alpha1"
-	"github.com/OffchainLabs/prysm/v6/testing/require"
-)
-
-func TestVerifyRegistrationSignature(t *testing.T) {
-	sk, err := bls.RandKey()
-	require.NoError(t, err)
-	reg := &ethpb.ValidatorRegistrationV1{
-		FeeRecipient: bytesutil.PadTo([]byte("fee"), 20),
-		GasLimit:     123456,
-		Timestamp:    uint64(time.Now().Unix()),
-		Pubkey:       sk.PublicKey().Marshal(),
-	}
-	d := params.BeaconConfig().DomainApplicationBuilder
-	domain, err := signing.ComputeDomain(d, nil, nil)
-	require.NoError(t, err)
-	sr, err := signing.ComputeSigningRoot(reg, domain)
-	require.NoError(t, err)
-	sk.Sign(sr[:]).Marshal()
-
-	sReg := &ethpb.SignedValidatorRegistrationV1{
-		Message:   reg,
-		Signature: sk.Sign(sr[:]).Marshal(),
-	}
-	require.NoError(t, signing.VerifyRegistrationSignature(sReg))
-
-	sReg.Signature = []byte("bad")
-	require.ErrorIs(t, signing.VerifyRegistrationSignature(sReg), signing.ErrSigFailedToVerify)
-
-	sReg.Message = nil
-	require.ErrorIs(t, signing.VerifyRegistrationSignature(sReg), signing.ErrNilRegistration)
-}

beacon-chain/das/BUILD.bazel

@@ -4,7 +4,6 @@ go_library(
     name = "go_default_library",
     srcs = [
         "availability_blobs.go",
-        "availability_columns.go",
         "blob_cache.go",
         "data_column_cache.go",
         "iface.go",
@@ -13,7 +12,6 @@ go_library(
     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",
@@ -23,7 +21,6 @@ go_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",
     ],
@@ -33,7 +30,6 @@ go_test(
     name = "go_default_test",
     srcs = [
         "availability_blobs_test.go",
-        "availability_columns_test.go",
         "blob_cache_test.go",
         "data_column_cache_test.go",
     ],
@@ -49,7 +45,6 @@ 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_blobs.go

@@ -53,30 +53,25 @@ 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 *LazilyPersistentStoreBlob) Persist(current primitives.Slot, sidecars ...blocks.ROSidecar) error {
+func (s *LazilyPersistentStoreBlob) Persist(current primitives.Slot, sidecars ...blocks.ROBlob) error {
 	if len(sidecars) == 0 {
 		return nil
 	}
 
-	blobSidecars, err := blocks.BlobSidecarsFromSidecars(sidecars)
-	if err != nil {
-		return errors.Wrap(err, "blob sidecars from sidecars")
-	}
-
-	if len(blobSidecars) > 1 {
-		firstRoot := blobSidecars[0].BlockRoot()
-		for _, sidecar := range blobSidecars[1:] {
+	if len(sidecars) > 1 {
+		firstRoot := sidecars[0].BlockRoot()
+		for _, sidecar := range sidecars[1:] {
 			if sidecar.BlockRoot() != firstRoot {
 				return errMixedRoots
 			}
 		}
 	}
-	if !params.WithinDAPeriod(slots.ToEpoch(blobSidecars[0].Slot()), slots.ToEpoch(current)) {
+	if !params.WithinDAPeriod(slots.ToEpoch(sidecars[0].Slot()), slots.ToEpoch(current)) {
 		return nil
 	}
-	key := keyFromSidecar(blobSidecars[0])
+	key := keyFromSidecar(sidecars[0])
 	entry := s.cache.ensure(key)
-	for _, blobSidecar := range blobSidecars {
+	for _, blobSidecar := range sidecars {
 		if err := entry.stash(&blobSidecar); err != nil {
 			return err
 		}

beacon-chain/das/availability_blobs_test.go

@@ -118,23 +118,21 @@ func TestLazilyPersistent_Missing(t *testing.T) {
 
 	blk, blobSidecars := util.GenerateTestDenebBlockWithSidecar(t, [32]byte{}, 1, 3)
 
-	scs := blocks.NewSidecarsFromBlobSidecars(blobSidecars)
-
 	mbv := &mockBlobBatchVerifier{t: t, scs: blobSidecars}
 	as := NewLazilyPersistentStore(store, mbv)
 
 	// Only one commitment persisted, should return error with other indices
-	require.NoError(t, as.Persist(1, scs[2]))
+	require.NoError(t, as.Persist(1, blobSidecars[2]))
 	err := as.IsDataAvailable(ctx, 1, blk)
 	require.ErrorIs(t, err, errMissingSidecar)
 
 	// All but one persisted, return missing idx
-	require.NoError(t, as.Persist(1, scs[0]))
+	require.NoError(t, as.Persist(1, blobSidecars[0]))
 	err = as.IsDataAvailable(ctx, 1, blk)
 	require.ErrorIs(t, err, errMissingSidecar)
 
 	// All persisted, return nil
-	require.NoError(t, as.Persist(1, scs...))
+	require.NoError(t, as.Persist(1, blobSidecars...))
 
 	require.NoError(t, as.IsDataAvailable(ctx, 1, blk))
 }
@@ -149,10 +147,8 @@ func TestLazilyPersistent_Mismatch(t *testing.T) {
 	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]))
+	require.NoError(t, as.Persist(1, blobSidecars[0]))
 	err := as.IsDataAvailable(ctx, 1, blk)
 	require.NotNil(t, err)
 	require.ErrorIs(t, err, errCommitmentMismatch)
@@ -161,29 +157,25 @@ func TestLazilyPersistent_Mismatch(t *testing.T) {
 func TestLazyPersistOnceCommitted(t *testing.T) {
 	_, 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...))
+	require.NoError(t, as.Persist(1, blobSidecars...))
 	// ignores duplicates
-	require.ErrorIs(t, as.Persist(1, scs...), ErrDuplicateSidecar)
+	require.ErrorIs(t, as.Persist(1, blobSidecars...), ErrDuplicateSidecar)
 
 	// ignores index out of bound
 	blobSidecars[0].Index = 6
-	require.ErrorIs(t, as.Persist(1, blocks.NewSidecarFromBlobSidecar(blobSidecars[0])), errIndexOutOfBounds)
+	require.ErrorIs(t, as.Persist(1, blobSidecars[0]), errIndexOutOfBounds)
 
 	_, moreBlobSidecars := util.GenerateTestDenebBlockWithSidecar(t, [32]byte{}, 1, 4)
 
-	more := blocks.NewSidecarsFromBlobSidecars(moreBlobSidecars)
-
 	// ignores sidecars before the retention period
 	slotOOB, err := slots.EpochStart(params.BeaconConfig().MinEpochsForBlobsSidecarsRequest)
 	require.NoError(t, err)
-	require.NoError(t, as.Persist(32+slotOOB, more[0]))
+	require.NoError(t, as.Persist(32+slotOOB, moreBlobSidecars[0]))
 
 	// doesn't ignore new sidecars with a different block root
-	require.NoError(t, as.Persist(1, more...))
+	require.NoError(t, as.Persist(1, moreBlobSidecars...))
 }
 
 type mockBlobBatchVerifier struct {

beacon-chain/das/availability_columns.go

@@ -1,213 +0,0 @@
-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
-	newDataColumnsVerifier verification.NewDataColumnsVerifier
-	custodyGroupCount      uint64
-}
-
-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)
-}
-
-// NewLazilyPersistentStoreColumn creates a new LazilyPersistentStoreColumn.
-// WARNING: The resulting LazilyPersistentStoreColumn is NOT thread-safe.
-func NewLazilyPersistentStoreColumn(
-	store *filesystem.DataColumnStorage,
-	nodeID enode.ID,
-	newDataColumnsVerifier verification.NewDataColumnsVerifier,
-	custodyGroupCount uint64,
-) *LazilyPersistentStoreColumn {
-	return &LazilyPersistentStoreColumn{
-		store:                  store,
-		nodeID:                 nodeID,
-		cache:                  newDataColumnCache(),
-		newDataColumnsVerifier: newDataColumnsVerifier,
-		custodyGroupCount:      custodyGroupCount,
-	}
-}
-
-// 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 := cacheKey{slot: firstSidecar.Slot(), root: firstSidecar.BlockRoot()}
-	entry := s.cache.ensure(key)
-
-	for _, sidecar := range dataColumnSidecars {
-		if err := entry.stash(&sidecar); 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 := cacheKey{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, "entry filter")
-	}
-
-	// https://github.com/ethereum/consensus-specs/blob/master/specs/fulu/p2p-interface.md#datacolumnsidecarsbyrange-v1
-	verifier := s.newDataColumnsVerifier(roDataColumns, verification.ByRangeRequestDataColumnSidecarRequirements)
-
-	if err := verifier.ValidFields(); err != nil {
-		return errors.Wrap(err, "valid fields")
-	}
-
-	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) {
-	samplesPerSlot := params.BeaconConfig().SamplesPerSlot
-
-	// 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 epoch.
-	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 peer info.
-	samplingSize := max(s.custodyGroupCount, samplesPerSlot)
-	peerInfo, _, err := peerdas.Info(nodeID, samplingSize)
-	if err != nil {
-		return nil, errors.Wrap(err, "peer info")
-	}
-
-	// Create a safe commitments array for the custody columns.
-	commitmentsArray := &safeCommitmentsArray{}
-	commitmentsArraySize := uint64(len(commitmentsArray))
-
-	for column := range peerInfo.CustodyColumns {
-		if column >= commitmentsArraySize {
-			return nil, errors.Errorf("custody column index %d too high (max allowed %d) - should never happen", column, commitmentsArraySize)
-		}
-
-		commitmentsArray[column] = kzgCommitments
-	}
-
-	return commitmentsArray, nil
-}

beacon-chain/das/availability_columns_test.go

@@ -1,313 +0,0 @@
-package das
-
-import (
-	"context"
-	"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/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"
-)
-
-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, 0)
-		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 := []util.DataColumnParam{
-			{Slot: 1, Index: 1},
-			{Slot: 2, Index: 2},
-		}
-
-		roSidecars, _ := roSidecarsFromDataColumnParamsByBlockRoot(t, dataColumnParamsByBlockRoot)
-		lazilyPersistentStoreColumns := NewLazilyPersistentStoreColumn(dataColumnStorage, enode.ID{}, nil, 0)
-
-		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 := []util.DataColumnParam{
-			{Slot: 1, Index: 1},
-		}
-
-		roSidecars, _ := roSidecarsFromDataColumnParamsByBlockRoot(t, dataColumnParamsByBlockRoot)
-		lazilyPersistentStoreColumns := NewLazilyPersistentStoreColumn(dataColumnStorage, enode.ID{}, nil, 0)
-
-		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) {
-		const slot = 42
-		dataColumnStorage := filesystem.NewEphemeralDataColumnStorage(t)
-
-		dataColumnParamsByBlockRoot := []util.DataColumnParam{
-			{Slot: slot, Index: 1},
-			{Slot: slot, Index: 5},
-		}
-
-		roSidecars, roDataColumns := roSidecarsFromDataColumnParamsByBlockRoot(t, dataColumnParamsByBlockRoot)
-		lazilyPersistentStoreColumns := NewLazilyPersistentStoreColumn(dataColumnStorage, enode.ID{}, nil, 0)
-
-		err := lazilyPersistentStoreColumns.Persist(slot, roSidecars...)
-		require.NoError(t, err)
-		require.Equal(t, 1, len(lazilyPersistentStoreColumns.cache.entries))
-
-		key := cacheKey{slot: slot, root: roDataColumns[0].BlockRoot()}
-		entry, ok := lazilyPersistentStoreColumns.cache.entries[key]
-		require.Equal(t, true, ok)
-
-		// 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 := t.Context()
-
-	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, 0)
-
-		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)
-		block := signedRoBlock.Block()
-		slot := block.Slot()
-		proposerIndex := block.ProposerIndex()
-		parentRoot := block.ParentRoot()
-		stateRoot := block.StateRoot()
-		bodyRoot, err := block.Body().HashTreeRoot()
-		require.NoError(t, err)
-
-		root := signedRoBlock.Root()
-
-		dataColumnStorage := filesystem.NewEphemeralDataColumnStorage(t)
-		lazilyPersistentStoreColumns := NewLazilyPersistentStoreColumn(dataColumnStorage, enode.ID{}, newDataColumnsVerifier, 0)
-
-		indices := [...]uint64{1, 17, 19, 42, 75, 87, 102, 117}
-		dataColumnsParams := make([]util.DataColumnParam, 0, len(indices))
-		for _, index := range indices {
-			dataColumnParams := util.DataColumnParam{
-				Index:          index,
-				KzgCommitments: commitments,
-
-				Slot:          slot,
-				ProposerIndex: proposerIndex,
-				ParentRoot:    parentRoot[:],
-				StateRoot:     stateRoot[:],
-				BodyRoot:      bodyRoot[:],
-			}
-
-			dataColumnsParams = append(dataColumnsParams, dataColumnParams)
-		}
-
-		_, verifiedRoDataColumns := util.CreateTestVerifiedRoDataColumnSidecars(t, dataColumnsParams)
-
-		key := cacheKey{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, 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) {
-			numberOfColumns := params.BeaconConfig().NumberOfColumns
-
-			b := tc.block(t)
-			s := NewLazilyPersistentStoreColumn(nil, enode.ID{}, nil, numberOfColumns)
-
-			commitmentsArray, err := s.fullCommitmentsToCheck(enode.ID{}, b, tc.slot)
-			require.NoError(t, err)
-
-			for _, commitments := range commitmentsArray {
-				require.DeepEqual(t, tc.commitments, commitments)
-			}
-		})
-	}
-}
-
-func roSidecarsFromDataColumnParamsByBlockRoot(t *testing.T, parameters []util.DataColumnParam) ([]blocks.ROSidecar, []blocks.RODataColumn) {
-	roDataColumns, _ := util.CreateTestVerifiedRoDataColumnSidecars(t, parameters)
-
-	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
-}
-
-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/blob_cache.go

@@ -99,20 +99,26 @@ func (e *blobCacheEntry) filter(root [32]byte, kc [][]byte, slot primitives.Slot
 		if e.diskSummary.HasIndex(i) {
 			continue
 		}
+		// Check if e.scs has this index before accessing
+		var sidecar *blocks.ROBlob
+		if i < uint64(len(e.scs)) {
+			sidecar = e.scs[i]
+		}
+
 		if kc[i] == nil {
-			if e.scs[i] != nil {
-				return nil, errors.Wrapf(errCommitmentMismatch, "root=%#x, index=%#x, commitment=%#x, no block commitment", root, i, e.scs[i].KzgCommitment)
+			if sidecar != nil {
+				return nil, errors.Wrapf(errCommitmentMismatch, "root=%#x, index=%#x, commitment=%#x, no block commitment", root, i, sidecar.KzgCommitment)
 			}
 			continue
 		}
 
-		if e.scs[i] == nil {
+		if sidecar == nil {
 			return nil, errors.Wrapf(errMissingSidecar, "root=%#x, index=%#x", root, i)
 		}
-		if !bytes.Equal(kc[i], e.scs[i].KzgCommitment) {
-			return nil, errors.Wrapf(errCommitmentMismatch, "root=%#x, index=%#x, commitment=%#x, block commitment=%#x", root, i, e.scs[i].KzgCommitment, kc[i])
+		if !bytes.Equal(kc[i], sidecar.KzgCommitment) {
+			return nil, errors.Wrapf(errCommitmentMismatch, "root=%#x, index=%#x, commitment=%#x, block commitment=%#x", root, i, sidecar.KzgCommitment, kc[i])
 		}
-		scs = append(scs, *e.scs[i])
+		scs = append(scs, *sidecar)
 	}
 
 	return scs, nil

beacon-chain/das/blob_cache_test.go

@@ -155,6 +155,41 @@ func TestFilter(t *testing.T) {
 			},
 			err: errCommitmentMismatch,
 		},
+		{
+			name: "empty scs array with commitments",
+			setup: func(t *testing.T) (*blobCacheEntry, [][]byte, []blocks.ROBlob) {
+				// This reproduces the panic condition where entry.scs is empty or nil
+				// but we have commitments to check
+				entry := &blobCacheEntry{
+					scs: nil, // Empty/nil array that caused the panic
+				}
+				// Create a commitment that would trigger the check at index 0
+				commits := [][]byte{
+					bytesutil.PadTo([]byte("commitment1"), 48),
+				}
+				return entry, commits, nil
+			},
+			err: errMissingSidecar,
+		},
+		{
+			name: "scs array shorter than commitments",
+			setup: func(t *testing.T) (*blobCacheEntry, [][]byte, []blocks.ROBlob) {
+				// This reproduces the condition where entry.scs exists but is shorter
+				// than the number of commitments we're checking
+				entry := &blobCacheEntry{
+					scs: make([]*blocks.ROBlob, 2), // Only 2 slots
+				}
+				// Create 4 commitments, accessing index 2 and 3 would have panicked
+				commits := [][]byte{
+					nil,
+					nil,
+					bytesutil.PadTo([]byte("commitment3"), 48),
+					bytesutil.PadTo([]byte("commitment4"), 48),
+				}
+				return entry, commits, nil
+			},
+			err: errMissingSidecar,
+		},
 	}
 	for _, c := range cases {
 		t.Run(c.name, func(t *testing.T) {

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.ROSidecar) error
+	Persist(current primitives.Slot, blobSidecar ...blocks.ROBlob) error
 }

beacon-chain/das/mock.go

@@ -5,13 +5,12 @@ 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.
 type MockAvailabilityStore struct {
 	VerifyAvailabilityCallback func(ctx context.Context, current primitives.Slot, b blocks.ROBlock) error
-	PersistBlobsCallback       func(current primitives.Slot, sc ...blocks.ROBlob) error
+	PersistBlobsCallback       func(current primitives.Slot, blobSidecar ...blocks.ROBlob) error
 }
 
 var _ AvailabilityStore = &MockAvailabilityStore{}
@@ -25,13 +24,9 @@ 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.ROSidecar) error {
-	blobSidecars, err := blocks.BlobSidecarsFromSidecars(sc)
-	if err != nil {
-		return errors.Wrap(err, "blob sidecars from sidecars")
-	}
+func (m *MockAvailabilityStore) Persist(current primitives.Slot, blobSidecar ...blocks.ROBlob) error {
 	if m.PersistBlobsCallback != nil {
-		return m.PersistBlobsCallback(current, blobSidecars...)
+		return m.PersistBlobsCallback(current, blobSidecar...)
 	}
 	return nil
 }

beacon-chain/db/filesystem/data_column.go

@@ -100,6 +100,14 @@ type (
 	}
 )
 
+// DataColumnStorageReader is an interface to read data column sidecars from the filesystem.
+type DataColumnStorageReader interface {
+	Summary(root [fieldparams.RootLength]byte) DataColumnStorageSummary
+	Get(root [fieldparams.RootLength]byte, indices []uint64) ([]blocks.VerifiedRODataColumn, error)
+}
+
+var _ DataColumnStorageReader = &DataColumnStorage{}
+
 // WithDataColumnBasePath is a required option that sets the base path of data column storage.
 func WithDataColumnBasePath(base string) DataColumnStorageOption {
 	return func(b *DataColumnStorage) error {

beacon-chain/db/filesystem/data_column_cache.go

@@ -84,12 +84,6 @@ func (s DataColumnStorageSummary) Stored() map[uint64]bool {
 	return stored
 }
 
-// DataColumnStorageSummarizer can be used to receive a summary of metadata about data columns on disk for a given root.
-// The DataColumnStorageSummary can be used to check which indices (if any) are available for a given block by root.
-type DataColumnStorageSummarizer interface {
-	Summary(root [fieldparams.RootLength]byte) DataColumnStorageSummary
-}
-
 type dataColumnStorageSummaryCache struct {
 	mu                 sync.RWMutex
 	dataColumnCount    float64
@@ -98,8 +92,6 @@ type dataColumnStorageSummaryCache struct {
 	cache              map[[fieldparams.RootLength]byte]DataColumnStorageSummary
 }
 
-var _ DataColumnStorageSummarizer = &dataColumnStorageSummaryCache{}
-
 func newDataColumnStorageSummaryCache() *dataColumnStorageSummaryCache {
 	return &dataColumnStorageSummaryCache{
 		cache:             make(map[[fieldparams.RootLength]byte]DataColumnStorageSummary),

beacon-chain/db/filesystem/mock.go

@@ -144,14 +144,3 @@ func NewEphemeralDataColumnStorageWithMocker(t testing.TB) (*DataColumnMocker, *
 	fs, dcs := NewEphemeralDataColumnStorageAndFs(t)
 	return &DataColumnMocker{fs: fs, dcs: dcs}, dcs
 }
-
-func NewMockDataColumnStorageSummarizer(t *testing.T, set map[[fieldparams.RootLength]byte][]uint64) DataColumnStorageSummarizer {
-	c := newDataColumnStorageSummaryCache()
-	for root, indices := range set {
-		if err := c.set(DataColumnsIdent{Root: root, Epoch: 0, Indices: indices}); err != nil {
-			t.Fatal(err)
-		}
-	}
-
-	return c
-}

beacon-chain/db/iface/interface.go

@@ -115,6 +115,17 @@ type NoHeadAccessDatabase interface {
 	CleanUpDirtyStates(ctx context.Context, slotsPerArchivedPoint primitives.Slot) error
 	DeleteHistoricalDataBeforeSlot(ctx context.Context, slot primitives.Slot, batchSize int) (int, error)
 
+	// Genesis operations.
+	LoadGenesis(ctx context.Context, stateBytes []byte) error
+	SaveGenesisData(ctx context.Context, state state.BeaconState) error
+	EnsureEmbeddedGenesis(ctx context.Context) error
+
+	// Support for checkpoint sync and backfill.
+	SaveOriginCheckpointBlockRoot(ctx context.Context, blockRoot [32]byte) error
+	SaveOrigin(ctx context.Context, serState, serBlock []byte) error
+	SaveBackfillStatus(context.Context, *dbval.BackfillStatus) error
+	BackfillFinalizedIndex(ctx context.Context, blocks []blocks.ROBlock, finalizedChildRoot [32]byte) error
+
 	// Custody operations.
 	UpdateSubscribedToAllDataSubnets(ctx context.Context, subscribed bool) (bool, error)
 	UpdateCustodyInfo(ctx context.Context, earliestAvailableSlot primitives.Slot, custodyGroupCount uint64) (primitives.Slot, uint64, error)
@@ -131,16 +142,6 @@ type HeadAccessDatabase interface {
 	HeadBlock(ctx context.Context) (interfaces.ReadOnlySignedBeaconBlock, error)
 	HeadBlockRoot() ([32]byte, error)
 	SaveHeadBlockRoot(ctx context.Context, blockRoot [32]byte) error
-
-	// Genesis operations.
-	LoadGenesis(ctx context.Context, stateBytes []byte) error
-	SaveGenesisData(ctx context.Context, state state.BeaconState) error
-	EnsureEmbeddedGenesis(ctx context.Context) error
-
-	// Support for checkpoint sync and backfill.
-	SaveOrigin(ctx context.Context, serState, serBlock []byte) error
-	SaveBackfillStatus(context.Context, *dbval.BackfillStatus) error
-	BackfillFinalizedIndex(ctx context.Context, blocks []blocks.ROBlock, finalizedChildRoot [32]byte) error
 }
 
 // SlasherDatabase interface for persisting data related to detecting slashable offenses on Ethereum.

beacon-chain/db/kv/wss_test.go

@@ -20,7 +20,7 @@ func TestSaveOrigin(t *testing.T) {
 
 	// Initialize genesis with mainnet config - this will load the embedded mainnet state
 	require.NoError(t, genesis.Initialize(ctx, t.TempDir()))
-	
+
 	// Get the initialized genesis state
 	st, err := genesis.State()
 	require.NoError(t, err)

beacon-chain/node/node.go

@@ -186,6 +186,7 @@ func New(cliCtx *cli.Context, cancel context.CancelFunc, opts ...Option) (*Beaco
 	beacon.ConfigOptions = append([]params.Option{params.WithGenesisValidatorsRoot(genesis.ValidatorsRoot())}, beacon.ConfigOptions...)
 	params.BeaconConfig().ApplyOptions(beacon.ConfigOptions...)
 	params.BeaconConfig().InitializeForkSchedule()
+	params.LogDigests(params.BeaconConfig())
 
 	synchronizer := startup.NewClockSynchronizer()
 	beacon.clockWaiter = synchronizer
@@ -844,6 +845,7 @@ func (b *BeaconNode) registerInitialSyncService(complete chan struct{}) error {
 		ClockWaiter:         b.clockWaiter,
 		InitialSyncComplete: complete,
 		BlobStorage:         b.BlobStorage,
+		DataColumnStorage:   b.DataColumnStorage,
 	}, opts...)
 	return b.services.RegisterService(is)
 }
@@ -965,6 +967,7 @@ 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,

beacon-chain/p2p/BUILD.bazel

@@ -72,7 +72,6 @@ go_library(
         "//monitoring/tracing:go_default_library",
         "//monitoring/tracing/trace:go_default_library",
         "//network:go_default_library",
-        "//network/forks:go_default_library",
         "//proto/prysm/v1alpha1:go_default_library",
         "//proto/prysm/v1alpha1/metadata:go_default_library",
         "//runtime:go_default_library",
@@ -169,7 +168,6 @@ go_test(
         "//crypto/hash:go_default_library",
         "//encoding/bytesutil:go_default_library",
         "//network:go_default_library",
-        "//network/forks:go_default_library",
         "//proto/eth/v1:go_default_library",
         "//proto/prysm/v1alpha1:go_default_library",
         "//proto/prysm/v1alpha1/metadata:go_default_library",
@@ -179,6 +177,7 @@ go_test(
         "//testing/util:go_default_library",
         "//time:go_default_library",
         "//time/slots:go_default_library",
+        "@com_github_ethereum_go_ethereum//common/hexutil:go_default_library",
         "@com_github_ethereum_go_ethereum//crypto:go_default_library",
         "@com_github_ethereum_go_ethereum//p2p/discover:go_default_library",
         "@com_github_ethereum_go_ethereum//p2p/enode:go_default_library",
@@ -196,7 +195,6 @@ go_test(
         "@com_github_multiformats_go_multiaddr//:go_default_library",
         "@com_github_pkg_errors//:go_default_library",
         "@com_github_prysmaticlabs_go_bitfield//:go_default_library",
-        "@com_github_sirupsen_logrus//:go_default_library",
         "@com_github_sirupsen_logrus//hooks/test:go_default_library",
         "@org_golang_google_protobuf//proto:go_default_library",
     ],

beacon-chain/p2p/broadcaster.go

@@ -15,7 +15,6 @@ import (
 	"github.com/OffchainLabs/prysm/v6/crypto/hash"
 	"github.com/OffchainLabs/prysm/v6/monitoring/tracing"
 	"github.com/OffchainLabs/prysm/v6/monitoring/tracing/trace"
-	"github.com/OffchainLabs/prysm/v6/network/forks"
 	ethpb "github.com/OffchainLabs/prysm/v6/proto/prysm/v1alpha1"
 	"github.com/OffchainLabs/prysm/v6/time/slots"
 	"github.com/pkg/errors"
@@ -274,14 +273,8 @@ func (s *Service) BroadcastLightClientOptimisticUpdate(ctx context.Context, upda
 		return errors.New("attempted to broadcast nil light client optimistic update")
 	}
 
-	forkDigest, err := forks.ForkDigestFromEpoch(slots.ToEpoch(update.AttestedHeader().Beacon().Slot), s.genesisValidatorsRoot)
-	if err != nil {
-		err := errors.Wrap(err, "could not retrieve fork digest")
-		tracing.AnnotateError(span, err)
-		return err
-	}
-
-	if err := s.broadcastObject(ctx, update, lcOptimisticToTopic(forkDigest)); err != nil {
+	digest := params.ForkDigest(slots.ToEpoch(update.AttestedHeader().Beacon().Slot))
+	if err := s.broadcastObject(ctx, update, lcOptimisticToTopic(digest)); err != nil {
 		log.WithError(err).Debug("Failed to broadcast light client optimistic update")
 		err := errors.Wrap(err, "could not publish message")
 		tracing.AnnotateError(span, err)
@@ -300,13 +293,7 @@ func (s *Service) BroadcastLightClientFinalityUpdate(ctx context.Context, update
 		return errors.New("attempted to broadcast nil light client finality update")
 	}
 
-	forkDigest, err := forks.ForkDigestFromEpoch(slots.ToEpoch(update.AttestedHeader().Beacon().Slot), s.genesisValidatorsRoot)
-	if err != nil {
-		err := errors.Wrap(err, "could not retrieve fork digest")
-		tracing.AnnotateError(span, err)
-		return err
-	}
-
+	forkDigest := params.ForkDigest(slots.ToEpoch(update.AttestedHeader().Beacon().Slot))
 	if err := s.broadcastObject(ctx, update, lcFinalityToTopic(forkDigest)); err != nil {
 		log.WithError(err).Debug("Failed to broadcast light client finality update")
 		err := errors.Wrap(err, "could not publish message")
@@ -318,15 +305,15 @@ func (s *Service) BroadcastLightClientFinalityUpdate(ctx context.Context, update
 	return nil
 }
 
-// BroadcastDataColumn broadcasts a data column to the p2p network, the message is assumed to be
+// BroadcastDataColumnSidecar broadcasts a data column to the p2p network, the message is assumed to be
 // broadcasted to the current fork and to the input column subnet.
-func (s *Service) BroadcastDataColumn(
+func (s *Service) BroadcastDataColumnSidecar(
 	root [fieldparams.RootLength]byte,
 	dataColumnSubnet uint64,
 	dataColumnSidecar *ethpb.DataColumnSidecar,
 ) error {
 	// Add tracing to the function.
-	ctx, span := trace.StartSpan(s.ctx, "p2p.BroadcastDataColumn")
+	ctx, span := trace.StartSpan(s.ctx, "p2p.BroadcastDataColumnSidecar")
 	defer span.End()
 
 	// Ensure the data column sidecar is not nil.
@@ -343,12 +330,12 @@ func (s *Service) BroadcastDataColumn(
 	}
 
 	// Non-blocking broadcast, with attempts to discover a column subnet peer if none available.
-	go s.internalBroadcastDataColumn(ctx, root, dataColumnSubnet, dataColumnSidecar, forkDigest)
+	go s.internalBroadcastDataColumnSidecar(ctx, root, dataColumnSubnet, dataColumnSidecar, forkDigest)
 
 	return nil
 }
 
-func (s *Service) internalBroadcastDataColumn(
+func (s *Service) internalBroadcastDataColumnSidecar(
 	ctx context.Context,
 	root [fieldparams.RootLength]byte,
 	columnSubnet uint64,
@@ -356,7 +343,7 @@ func (s *Service) internalBroadcastDataColumn(
 	forkDigest [fieldparams.VersionLength]byte,
 ) {
 	// Add tracing to the function.
-	_, span := trace.StartSpan(ctx, "p2p.internalBroadcastDataColumn")
+	_, span := trace.StartSpan(ctx, "p2p.internalBroadcastDataColumnSidecar")
 	defer span.End()
 
 	// Increase the number of broadcast attempts.

beacon-chain/p2p/broadcaster_test.go

@@ -15,12 +15,13 @@ import (
 	"github.com/OffchainLabs/prysm/v6/beacon-chain/p2p/peers"
 	"github.com/OffchainLabs/prysm/v6/beacon-chain/p2p/peers/scorers"
 	p2ptest "github.com/OffchainLabs/prysm/v6/beacon-chain/p2p/testing"
+	"github.com/OffchainLabs/prysm/v6/beacon-chain/startup"
 	"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/interfaces"
 	"github.com/OffchainLabs/prysm/v6/consensus-types/wrapper"
 	"github.com/OffchainLabs/prysm/v6/encoding/bytesutil"
-	"github.com/OffchainLabs/prysm/v6/network/forks"
 	ethpb "github.com/OffchainLabs/prysm/v6/proto/prysm/v1alpha1"
 	testpb "github.com/OffchainLabs/prysm/v6/proto/testing"
 	"github.com/OffchainLabs/prysm/v6/testing/assert"
@@ -59,6 +60,7 @@ func TestService_Broadcast(t *testing.T) {
 	topic := "/eth2/%x/testing"
 	// Set a test gossip mapping for testpb.TestSimpleMessage.
 	GossipTypeMapping[reflect.TypeOf(msg)] = topic
+	p.clock = startup.NewClock(p.genesisTime, bytesutil.ToBytes32(p.genesisValidatorsRoot))
 	digest, err := p.currentForkDigest()
 	require.NoError(t, err)
 	topic = fmt.Sprintf(topic, digest)
@@ -551,9 +553,7 @@ func TestService_BroadcastLightClientOptimisticUpdate(t *testing.T) {
 	require.NoError(t, err)
 
 	GossipTypeMapping[reflect.TypeOf(msg)] = LightClientOptimisticUpdateTopicFormat
-	digest, err := forks.ForkDigestFromEpoch(slots.ToEpoch(msg.AttestedHeader().Beacon().Slot), p.genesisValidatorsRoot)
-	require.NoError(t, err)
-	topic := fmt.Sprintf(LightClientOptimisticUpdateTopicFormat, digest)
+	topic := fmt.Sprintf(LightClientOptimisticUpdateTopicFormat, params.ForkDigest(slots.ToEpoch(msg.AttestedHeader().Beacon().Slot)))
 
 	// External peer subscribes to the topic.
 	topic += p.Encoding().ProtocolSuffix()
@@ -617,9 +617,7 @@ func TestService_BroadcastLightClientFinalityUpdate(t *testing.T) {
 	require.NoError(t, err)
 
 	GossipTypeMapping[reflect.TypeOf(msg)] = LightClientFinalityUpdateTopicFormat
-	digest, err := forks.ForkDigestFromEpoch(slots.ToEpoch(msg.AttestedHeader().Beacon().Slot), p.genesisValidatorsRoot)
-	require.NoError(t, err)
-	topic := fmt.Sprintf(LightClientFinalityUpdateTopicFormat, digest)
+	topic := fmt.Sprintf(LightClientFinalityUpdateTopicFormat, params.ForkDigest(slots.ToEpoch(msg.AttestedHeader().Beacon().Slot)))
 
 	// External peer subscribes to the topic.
 	topic += p.Encoding().ProtocolSuffix()
@@ -718,7 +716,7 @@ func TestService_BroadcastDataColumn(t *testing.T) {
 
 	// Attempt to broadcast nil object should fail.
 	var emptyRoot [fieldparams.RootLength]byte
-	err = service.BroadcastDataColumn(emptyRoot, subnet, nil)
+	err = service.BroadcastDataColumnSidecar(emptyRoot, subnet, nil)
 	require.ErrorContains(t, "attempted to broadcast nil", err)
 
 	// Subscribe to the topic.
@@ -729,7 +727,7 @@ func TestService_BroadcastDataColumn(t *testing.T) {
 	time.Sleep(50 * time.Millisecond)
 
 	// Broadcast to peers and wait.
-	err = service.BroadcastDataColumn(emptyRoot, subnet, sidecar)
+	err = service.BroadcastDataColumnSidecar(emptyRoot, subnet, sidecar)
 	require.NoError(t, err)
 
 	// Receive the message.

beacon-chain/p2p/discovery.go

@@ -443,20 +443,27 @@ func (s *Service) findPeers(ctx context.Context, missingPeerCount uint) ([]*enod
 			return peersToDial, ctx.Err()
 		}
 
-		// Skip peer not matching the filter.
 		node := iterator.Node()
-		if !s.filterPeer(node) {
-			continue
-		}
 
 		// Remove duplicates, keeping the node with higher seq.
 		existing, ok := nodeByNodeID[node.ID()]
-		if ok && existing.Seq() > node.Seq() {
+		if ok && existing.Seq() >= node.Seq() {
+			continue // keep existing and skip.
+		}
+
+		// Treat nodes that exist in nodeByNodeID with higher seq numbers as new peers
+		// Skip peer not matching the filter.
+		if !s.filterPeer(node) {
+			if ok {
+				// this means the existing peer with the lower sequence number is no longer valid
+				delete(nodeByNodeID, existing.ID())
+				missingPeerCount++
+			}
 			continue
 		}
-		nodeByNodeID[node.ID()] = node
 
 		// We found a new peer. Decrease the missing peer count.
+		nodeByNodeID[node.ID()] = node
 		missingPeerCount--
 	}
 
@@ -585,8 +592,11 @@ func (s *Service) createLocalNode(
 	localNode.SetFallbackIP(ipAddr)
 	localNode.SetFallbackUDP(udpPort)
 
-	localNode, err = addForkEntry(localNode, s.genesisTime, s.genesisValidatorsRoot)
-	if err != nil {
+	currentSlot := slots.CurrentSlot(s.genesisTime)
+	currentEpoch := slots.ToEpoch(currentSlot)
+	current := params.GetNetworkScheduleEntry(currentEpoch)
+	next := params.NextNetworkScheduleEntry(currentEpoch)
+	if err := updateENR(localNode, current, next); err != nil {
 		return nil, errors.Wrap(err, "could not add eth2 fork version entry to enr")
 	}
 
@@ -707,7 +717,7 @@ func (s *Service) filterPeer(node *enode.Node) bool {
 	// Ignore nodes that don't match our fork digest.
 	nodeENR := node.Record()
 	if s.genesisValidatorsRoot != nil {
-		if err := s.compareForkENR(nodeENR); err != nil {
+		if err := compareForkENR(s.dv5Listener.LocalNode().Node().Record(), nodeENR); err != nil {
 			log.WithError(err).Trace("Fork ENR mismatches between peer and local node")
 			return false
 		}

beacon-chain/p2p/discovery_test.go

@@ -1,9 +1,11 @@
 package p2p
 
 import (
+	"bytes"
 	"context"
 	"crypto/ecdsa"
 	"crypto/rand"
+	"crypto/sha256"
 	"fmt"
 	mathRand "math/rand"
 	"net"
@@ -58,6 +60,81 @@ func createAddrAndPrivKey(t *testing.T) (net.IP, *ecdsa.PrivateKey) {
 	return ipAddr, pkey
 }
 
+// createTestNodeWithID creates a LocalNode for testing with deterministic private key
+// This is needed for deduplication tests where we need the same node ID across different sequence numbers
+func createTestNodeWithID(t *testing.T, id string) *enode.LocalNode {
+	// Create a deterministic reader based on the ID for consistent key generation
+	h := sha256.New()
+	h.Write([]byte(id))
+	seedBytes := h.Sum(nil)
+
+	// Create a deterministic reader using the seed
+	deterministicReader := bytes.NewReader(seedBytes)
+
+	// Generate the private key using the same approach as the production code
+	privKey, _, err := crypto.GenerateSecp256k1Key(deterministicReader)
+	require.NoError(t, err)
+
+	// Convert to ECDSA private key for enode usage
+	ecdsaPrivKey, err := ecdsaprysm.ConvertFromInterfacePrivKey(privKey)
+	require.NoError(t, err)
+
+	db, err := enode.OpenDB("")
+	require.NoError(t, err)
+	t.Cleanup(func() { db.Close() })
+
+	localNode := enode.NewLocalNode(db, ecdsaPrivKey)
+
+	// Set basic properties
+	localNode.SetStaticIP(net.ParseIP("127.0.0.1"))
+	localNode.Set(enr.TCP(3000))
+	localNode.Set(enr.UDP(3000))
+	localNode.Set(enr.WithEntry(eth2EnrKey, make([]byte, 16)))
+
+	return localNode
+}
+
+// createTestNodeRandom creates a LocalNode for testing using the existing createAddrAndPrivKey function
+func createTestNodeRandom(t *testing.T) *enode.LocalNode {
+	_, privKey := createAddrAndPrivKey(t)
+
+	db, err := enode.OpenDB("")
+	require.NoError(t, err)
+	t.Cleanup(func() { db.Close() })
+
+	localNode := enode.NewLocalNode(db, privKey)
+
+	// Set basic properties
+	localNode.SetStaticIP(net.ParseIP("127.0.0.1"))
+	localNode.Set(enr.TCP(3000))
+	localNode.Set(enr.UDP(3000))
+	localNode.Set(enr.WithEntry(eth2EnrKey, make([]byte, 16)))
+
+	return localNode
+}
+
+// setNodeSeq updates a LocalNode to have the specified sequence number
+func setNodeSeq(localNode *enode.LocalNode, seq uint64) {
+	// Force set the sequence number - we need to update the record seq-1 times
+	// because it starts at 1
+	currentSeq := localNode.Node().Seq()
+	for currentSeq < seq {
+		localNode.Set(enr.WithEntry("dummy", currentSeq))
+		currentSeq++
+	}
+}
+
+// setNodeSubnets sets the attestation subnets for a LocalNode
+func setNodeSubnets(localNode *enode.LocalNode, attSubnets []uint64) {
+	if len(attSubnets) > 0 {
+		bitV := bitfield.NewBitvector64()
+		for _, subnet := range attSubnets {
+			bitV.SetBitAt(subnet, true)
+		}
+		localNode.Set(enr.WithEntry(attSubnetEnrKey, &bitV))
+	}
+}
+
 func TestCreateListener(t *testing.T) {
 	port := 1024
 	ipAddr, pkey := createAddrAndPrivKey(t)
@@ -241,7 +318,7 @@ func TestCreateLocalNode(t *testing.T) {
 
 			// Check fork is set.
 			fork := new([]byte)
-			require.NoError(t, localNode.Node().Record().Load(enr.WithEntry(eth2ENRKey, fork)))
+			require.NoError(t, localNode.Node().Record().Load(enr.WithEntry(eth2EnrKey, fork)))
 			require.NotEmpty(t, *fork)
 
 			// Check att subnets.
@@ -492,7 +569,7 @@ func TestMultipleDiscoveryAddresses(t *testing.T) {
 	node := enode.NewLocalNode(db, key)
 	node.Set(enr.IPv4{127, 0, 0, 1})
 	node.Set(enr.IPv6{0x20, 0x01, 0x48, 0x60, 0, 0, 0x20, 0x01, 0, 0, 0, 0, 0, 0, 0x00, 0x68})
-	s := &Service{dv5Listener: mockListener{localNode: node}}
+	s := &Service{dv5Listener: testp2p.NewMockListener(node, nil)}
 
 	multiAddresses, err := s.DiscoveryAddresses()
 	require.NoError(t, err)
@@ -517,7 +594,7 @@ func TestDiscoveryV5_SeqNumber(t *testing.T) {
 	node := enode.NewLocalNode(db, key)
 	node.Set(enr.IPv4{127, 0, 0, 1})
 	currentSeq := node.Seq()
-	s := &Service{dv5Listener: mockListener{localNode: node}}
+	s := &Service{dv5Listener: testp2p.NewMockListener(node, nil)}
 	_, err = s.DiscoveryAddresses()
 	require.NoError(t, err)
 	newSeq := node.Seq()
@@ -529,7 +606,7 @@ func TestDiscoveryV5_SeqNumber(t *testing.T) {
 	nodeTwo.Set(enr.IPv6{0x20, 0x01, 0x48, 0x60, 0, 0, 0x20, 0x01, 0, 0, 0, 0, 0, 0, 0x00, 0x68})
 	seqTwo := nodeTwo.Seq()
 	assert.NotEqual(t, seqTwo, newSeq)
-	sTwo := &Service{dv5Listener: mockListener{localNode: nodeTwo}}
+	sTwo := &Service{dv5Listener: testp2p.NewMockListener(nodeTwo, nil)}
 	_, err = sTwo.DiscoveryAddresses()
 	require.NoError(t, err)
 	assert.Equal(t, seqTwo+1, nodeTwo.Seq())
@@ -886,3 +963,291 @@ func TestRefreshPersistentSubnets(t *testing.T) {
 	// Reset the config.
 	params.OverrideBeaconConfig(defaultCfg)
 }
+
+func TestFindPeers_NodeDeduplication(t *testing.T) {
+	params.SetupTestConfigCleanup(t)
+	cache.SubnetIDs.EmptyAllCaches()
+	defer cache.SubnetIDs.EmptyAllCaches()
+
+	ctx := context.Background()
+
+	// Create LocalNodes and manipulate sequence numbers
+	localNode1 := createTestNodeWithID(t, "node1")
+	localNode2 := createTestNodeWithID(t, "node2")
+	localNode3 := createTestNodeWithID(t, "node3")
+
+	// Create different sequence versions of node1
+	setNodeSeq(localNode1, 1)
+	node1_seq1 := localNode1.Node()
+	setNodeSeq(localNode1, 2)
+	node1_seq2 := localNode1.Node() // Same ID, higher seq
+	setNodeSeq(localNode1, 3)
+	node1_seq3 := localNode1.Node() // Same ID, even higher seq
+
+	// Other nodes with seq 1
+	node2_seq1 := localNode2.Node()
+	node3_seq1 := localNode3.Node()
+
+	tests := []struct {
+		name          string
+		nodes         []*enode.Node
+		missingPeers  uint
+		expectedCount int
+		description   string
+		eval          func(t *testing.T, result []*enode.Node)
+	}{
+		{
+			name: "No duplicates - all unique nodes",
+			nodes: []*enode.Node{
+				node2_seq1,
+				node3_seq1,
+			},
+			missingPeers:  2,
+			expectedCount: 2,
+			description:   "Should return all unique nodes without deduplication",
+			eval:          nil, // No special validation needed
+		},
+		{
+			name: "Duplicate with lower seq comes first - should replace",
+			nodes: []*enode.Node{
+				node1_seq1,
+				node1_seq2, // Higher seq, should replace
+				node2_seq1, // Different node added after duplicates are processed
+			},
+			missingPeers:  2, // Need 2 peers so we process all nodes
+			expectedCount: 2, // Should get node1 (with higher seq) and node2
+			description:   "Should keep node with higher sequence number when duplicate found",
+			eval: func(t *testing.T, result []*enode.Node) {
+				// Should have node2 and node1 with higher seq (node1_seq2)
+				foundNode1WithHigherSeq := false
+				for _, node := range result {
+					if node.ID() == node1_seq2.ID() {
+						require.Equal(t, node1_seq2.Seq(), node.Seq(), "Node1 should have higher seq")
+						foundNode1WithHigherSeq = true
+					}
+				}
+				require.Equal(t, true, foundNode1WithHigherSeq, "Should have node1 with higher seq")
+			},
+		},
+		{
+			name: "Duplicate with higher seq comes first - should keep existing",
+			nodes: []*enode.Node{
+				node1_seq3, // Higher seq
+				node1_seq2, // Lower seq, should be skipped (continue branch)
+				node1_seq1, // Even lower seq, should also be skipped (continue branch)
+				node2_seq1, // Different node added after duplicates are processed
+			},
+			missingPeers:  2,
+			expectedCount: 2,
+			description:   "Should keep existing node when it has higher sequence number and skip all lower seq duplicates",
+			eval: func(t *testing.T, result []*enode.Node) {
+				// Should have kept the node with highest seq (node1_seq3)
+				foundNode1WithHigherSeq := false
+				for _, node := range result {
+					if node.ID() == node1_seq3.ID() {
+						require.Equal(t, node1_seq3.Seq(), node.Seq(), "Node1 should have highest seq")
+						foundNode1WithHigherSeq = true
+					}
+				}
+				require.Equal(t, true, foundNode1WithHigherSeq, "Should have node1 with highest seq")
+			},
+		},
+		{
+			name: "Multiple duplicates with increasing seq",
+			nodes: []*enode.Node{
+				node1_seq1,
+				node1_seq2, // Should replace seq1
+				node1_seq3, // Should replace seq2
+				node2_seq1, // Different node added after duplicates are processed
+			},
+			missingPeers:  2,
+			expectedCount: 2,
+			description:   "Should keep updating to highest sequence number",
+			eval: func(t *testing.T, result []*enode.Node) {
+				// Should have the node with highest seq (node1_seq3)
+				foundNode1WithHigherSeq := false
+				for _, node := range result {
+					if node.ID() == node1_seq3.ID() {
+						require.Equal(t, node1_seq3.Seq(), node.Seq(), "Node1 should have highest seq")
+						foundNode1WithHigherSeq = true
+					}
+				}
+				require.Equal(t, true, foundNode1WithHigherSeq, "Should have node1 with highest seq")
+			},
+		},
+		{
+			name: "Duplicate with equal seq comes after - should skip",
+			nodes: []*enode.Node{
+				node1_seq2, // First occurrence
+				node1_seq2, // Same exact node instance, should be skipped (continue branch for >= case)
+				node2_seq1, // Different node
+			},
+			missingPeers:  2,
+			expectedCount: 2,
+			description:   "Should skip duplicate with equal sequence number",
+			eval: func(t *testing.T, result []*enode.Node) {
+				// Should have exactly one instance of node1_seq2 and one instance of node2_seq1
+				foundNode1 := false
+				foundNode2 := false
+				for _, node := range result {
+					if node.ID() == node1_seq2.ID() {
+						require.Equal(t, node1_seq2.Seq(), node.Seq(), "Node1 should have the expected seq")
+						require.Equal(t, false, foundNode1, "Should have only one instance of node1") // Ensure no duplicates
+						foundNode1 = true
+					}
+					if node.ID() == node2_seq1.ID() {
+						foundNode2 = true
+					}
+				}
+				require.Equal(t, true, foundNode1, "Should have node1")
+				require.Equal(t, true, foundNode2, "Should have node2")
+			},
+		},
+		{
+			name: "Mix of unique and duplicate nodes",
+			nodes: []*enode.Node{
+				node1_seq1,
+				node2_seq1,
+				node1_seq2, // Should replace node1_seq1
+				node3_seq1,
+				node1_seq3, // Should replace node1_seq2
+			},
+			missingPeers:  3,
+			expectedCount: 3,
+			description:   "Should handle mix of unique nodes and duplicates correctly",
+			eval:          nil, // Basic count validation is sufficient
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			fakePeer := testp2p.NewTestP2P(t)
+
+			s := &Service{
+				cfg: &Config{
+					MaxPeers: 30,
+				},
+				genesisValidatorsRoot: bytesutil.PadTo([]byte{'A'}, 32),
+				peers: peers.NewStatus(ctx, &peers.StatusConfig{
+					PeerLimit:    30,
+					ScorerParams: &scorers.Config{},
+				}),
+				host: fakePeer.BHost,
+			}
+
+			localNode := createTestNodeRandom(t)
+			mockIter := testp2p.NewMockIterator(tt.nodes)
+			s.dv5Listener = testp2p.NewMockListener(localNode, mockIter)
+
+			ctxWithTimeout, cancel := context.WithTimeout(ctx, 1*time.Second)
+			defer cancel()
+
+			result, err := s.findPeers(ctxWithTimeout, tt.missingPeers)
+
+			require.NoError(t, err, tt.description)
+			require.Equal(t, tt.expectedCount, len(result), tt.description)
+
+			if tt.eval != nil {
+				tt.eval(t, result)
+			}
+		})
+	}
+}
+
+// callbackIterator allows us to execute callbacks at specific points during iteration
+type callbackIterator struct {
+	nodes     []*enode.Node
+	index     int
+	callbacks map[int]func() // map from index to callback function
+}
+
+func (c *callbackIterator) Next() bool {
+	// Execute callback before checking if we can continue (if one exists)
+	if callback, exists := c.callbacks[c.index]; exists {
+		callback()
+	}
+
+	return c.index < len(c.nodes)
+}
+
+func (c *callbackIterator) Node() *enode.Node {
+	if c.index >= len(c.nodes) {
+		return nil
+	}
+
+	node := c.nodes[c.index]
+	c.index++
+	return node
+}
+
+func (c *callbackIterator) Close() {
+	// Nothing to clean up for this simple implementation
+}
+
+func TestFindPeers_received_bad_existing_node(t *testing.T) {
+	// This test successfully triggers delete(nodeByNodeID, node.ID()) in subnets.go by:
+	// 1. Processing node1_seq1 first (passes filterPeer, gets added to map
+	// 2. Callback marks peer as bad before processing node1_seq2"
+	// 3. Processing node1_seq2 (fails filterPeer, triggers delete since ok=true
+	params.SetupTestConfigCleanup(t)
+	cache.SubnetIDs.EmptyAllCaches()
+	defer cache.SubnetIDs.EmptyAllCaches()
+
+	ctx := context.Background()
+
+	// Create LocalNode with same ID but different sequences
+	localNode1 := createTestNodeWithID(t, "testnode")
+	node1_seq1 := localNode1.Node() // Get current node
+	currentSeq := node1_seq1.Seq()
+	setNodeSeq(localNode1, currentSeq+1) // Increment sequence by 1
+	node1_seq2 := localNode1.Node()      // This should have higher seq
+
+	// Additional node to ensure we have enough peers to process
+	localNode2 := createTestNodeWithID(t, "othernode")
+	node2 := localNode2.Node()
+
+	fakePeer := testp2p.NewTestP2P(t)
+
+	service := &Service{
+		cfg: &Config{
+			MaxPeers: 30,
+		},
+		genesisValidatorsRoot: bytesutil.PadTo([]byte{'A'}, 32),
+		peers: peers.NewStatus(ctx, &peers.StatusConfig{
+			PeerLimit:    30,
+			ScorerParams: &scorers.Config{},
+		}),
+		host: fakePeer.BHost,
+	}
+
+	// Create iterator with callback that marks peer as bad before processing node1_seq2
+	iter := &callbackIterator{
+		nodes: []*enode.Node{node1_seq1, node1_seq2, node2},
+		index: 0,
+		callbacks: map[int]func(){
+			1: func() { // Before processing node1_seq2 (index 1)
+				// Mark peer as bad before processing node1_seq2
+				peerData, _, _ := convertToAddrInfo(node1_seq2)
+				if peerData != nil {
+					service.peers.Add(node1_seq2.Record(), peerData.ID, nil, network.DirUnknown)
+					// Mark as bad peer - need enough increments to exceed threshold (6)
+					for i := 0; i < 10; i++ {
+						service.peers.Scorers().BadResponsesScorer().Increment(peerData.ID)
+					}
+				}
+			},
+		},
+	}
+
+	localNode := createTestNodeRandom(t)
+	service.dv5Listener = testp2p.NewMockListener(localNode, iter)
+
+	// Run findPeers - node1_seq1 gets processed first, then callback marks peer bad, then node1_seq2 fails
+	ctxWithTimeout, cancel := context.WithTimeout(ctx, 1*time.Second)
+	defer cancel()
+
+	result, err := service.findPeers(ctxWithTimeout, 3)
+
+	require.NoError(t, err)
+	require.Equal(t, 1, len(result))
+}

beacon-chain/p2p/fork.go

@@ -3,12 +3,9 @@ package p2p
 import (
 	"bytes"
 	"fmt"
-	"time"
 
 	"github.com/OffchainLabs/prysm/v6/config/params"
-	"github.com/OffchainLabs/prysm/v6/network/forks"
 	pb "github.com/OffchainLabs/prysm/v6/proto/prysm/v1alpha1"
-	prysmTime "github.com/OffchainLabs/prysm/v6/time"
 	"github.com/OffchainLabs/prysm/v6/time/slots"
 	"github.com/ethereum/go-ethereum/p2p/enode"
 	"github.com/ethereum/go-ethereum/p2p/enr"
@@ -16,8 +13,17 @@ import (
 	"github.com/sirupsen/logrus"
 )
 
-// ENR key used for Ethereum consensus-related fork data.
-var eth2ENRKey = params.BeaconNetworkConfig().ETH2Key
+var (
+	errForkScheduleMismatch  = errors.New("peer fork schedule incompatible")
+	errCurrentDigestMismatch = errors.Wrap(errForkScheduleMismatch, "current_fork_digest mismatch")
+	errNextVersionMismatch   = errors.Wrap(errForkScheduleMismatch, "next_fork_version mismatch")
+	errNextDigestMismatch    = errors.Wrap(errForkScheduleMismatch, "nfd (next fork digest) mismatch")
+)
+
+const (
+	eth2EnrKey = "eth2" // The `eth2` ENR entry advertizes the node's view of the fork schedule with an ssz-encoded ENRForkID value.
+	nfdEnrKey  = "nfd"  // The `nfd` ENR entry separately advertizes the "next fork digest" aspect of the fork schedule.
+)
 
 // ForkDigest returns the current fork digest of
 // the node according to the local clock.
@@ -25,97 +31,136 @@ func (s *Service) currentForkDigest() ([4]byte, error) {
 	if !s.isInitialized() {
 		return [4]byte{}, errors.New("state is not initialized")
 	}
-	return forks.CreateForkDigest(s.genesisTime, s.genesisValidatorsRoot)
+
+	currentSlot := slots.CurrentSlot(s.genesisTime)
+	currentEpoch := slots.ToEpoch(currentSlot)
+	return params.ForkDigest(currentEpoch), nil
 }
 
 // Compares fork ENRs between an incoming peer's record and our node's
 // local record values for current and next fork version/epoch.
-func (s *Service) compareForkENR(record *enr.Record) error {
-	currentRecord := s.dv5Listener.LocalNode().Node().Record()
-	peerForkENR, err := forkEntry(record)
+func compareForkENR(self, peer *enr.Record) error {
+	peerEntry, err := forkEntry(peer)
 	if err != nil {
 		return err
 	}
-	currentForkENR, err := forkEntry(currentRecord)
+	selfEntry, err := forkEntry(self)
 	if err != nil {
 		return err
 	}
-	enrString, err := SerializeENR(record)
+	peerString, err := SerializeENR(peer)
 	if err != nil {
 		return err
 	}
 	// Clients SHOULD connect to peers with current_fork_digest, next_fork_version,
 	// and next_fork_epoch that match local values.
-	if !bytes.Equal(peerForkENR.CurrentForkDigest, currentForkENR.CurrentForkDigest) {
-		return fmt.Errorf(
+	if !bytes.Equal(peerEntry.CurrentForkDigest, selfEntry.CurrentForkDigest) {
+		return errors.Wrapf(errCurrentDigestMismatch,
 			"fork digest of peer with ENR %s: %v, does not match local value: %v",
-			enrString,
-			peerForkENR.CurrentForkDigest,
-			currentForkENR.CurrentForkDigest,
+			peerString,
+			peerEntry.CurrentForkDigest,
+			selfEntry.CurrentForkDigest,
 		)
 	}
+
 	// Clients MAY connect to peers with the same current_fork_version but a
 	// different next_fork_version/next_fork_epoch. Unless ENRForkID is manually
 	// updated to matching prior to the earlier next_fork_epoch of the two clients,
 	// these type of connecting clients will be unable to successfully interact
 	// starting at the earlier next_fork_epoch.
-	if peerForkENR.NextForkEpoch != currentForkENR.NextForkEpoch {
+	if peerEntry.NextForkEpoch != selfEntry.NextForkEpoch {
 		log.WithFields(logrus.Fields{
-			"peerNextForkEpoch": peerForkENR.NextForkEpoch,
-			"peerENR":           enrString,
+			"peerNextForkEpoch":   peerEntry.NextForkEpoch,
+			"peerNextForkVersion": peerEntry.NextForkVersion,
+			"peerENR":             peerString,
 		}).Trace("Peer matches fork digest but has different next fork epoch")
+		// We allow the connection because we have a different view of the next fork epoch. This
+		// could be due to peers that have no upgraded ahead of a fork or BPO schedule change, so
+		// we allow the connection to continue until the fork boundary.
+		return nil
 	}
-	if !bytes.Equal(peerForkENR.NextForkVersion, currentForkENR.NextForkVersion) {
-		log.WithFields(logrus.Fields{
-			"peerNextForkVersion": peerForkENR.NextForkVersion,
-			"peerENR":             enrString,
-		}).Trace("Peer matches fork digest but has different next fork version")
+
+	// Since we agree on the next fork epoch, we require next fork version to also be in agreement.
+	if !bytes.Equal(peerEntry.NextForkVersion, selfEntry.NextForkVersion) {
+		return errors.Wrapf(errNextVersionMismatch,
+			"next fork version of peer with ENR %s: %#x, does not match local value: %#x",
+			peerString, peerEntry.NextForkVersion, selfEntry.NextForkVersion)
+	}
+
+	// Fulu adds the following to the spec:
+	// ---
+	// A new entry is added to the ENR under the key nfd, short for next fork digest. This entry
+	// communicates the digest of the next scheduled fork, regardless of whether it is a regular
+	// or a Blob-Parameters-Only fork. This new entry MUST be added once FULU_FORK_EPOCH is assigned
+	// any value other than FAR_FUTURE_EPOCH. Adding this entry prior to the Fulu fork will not
+	// impact peering as nodes will ignore unknown ENR entries and nfd mismatches do not cause
+	// disconnects.
+	// When discovering and interfacing with peers, nodes MUST evaluate nfd alongside their existing
+	// consideration of the ENRForkID::next_* fields under the eth2 key, to form a more accurate
+	// view of the peer's intended next fork for the purposes of sustained peering. If there is a
+	// mismatch, the node MUST NOT disconnect before the fork boundary, but it MAY disconnect
+	// at/after the fork boundary.
+
+	// Nodes unprepared to follow the Fulu fork will be unaware of nfd entries. However, their
+	// existing comparison of eth2 entries (concretely next_fork_epoch) is sufficient to detect
+	// upcoming divergence.
+	// ---
+
+	// Because this is a new in-bound connection, we lean into the pre-fulu point that clients
+	// MAY connect to peers with the same current_fork_version but a different
+	// next_fork_version/next_fork_epoch, which implies we can chose to not connect to them when these
+	// don't match.
+	//
+	// Given that the next_fork_epoch matches, we will require the next_fork_digest to match.
+	if !params.FuluEnabled() {
+		return nil
+	}
+	peerNFD, selfNFD := nfd(peer), nfd(self)
+	if peerNFD != selfNFD {
+		return errors.Wrapf(errNextDigestMismatch,
+			"next fork digest of peer with ENR %s: %v, does not match local value: %v",
+			peerString, peerNFD, selfNFD)
 	}
 	return nil
 }
 
-// Adds a fork entry as an ENR record under the Ethereum consensus EnrKey for
-// the local node. The fork entry is an ssz-encoded enrForkID type
-// which takes into account the current fork version from the current
-// epoch to create a fork digest, the next fork version,
-// and the next fork epoch.
-func addForkEntry(
-	node *enode.LocalNode,
-	genesisTime time.Time,
-	genesisValidatorsRoot []byte,
-) (*enode.LocalNode, error) {
-	digest, err := forks.CreateForkDigest(genesisTime, genesisValidatorsRoot)
-	if err != nil {
-		return nil, err
-	}
-	currentSlot := slots.CurrentSlot(genesisTime)
-	currentEpoch := slots.ToEpoch(currentSlot)
-	if prysmTime.Now().Before(genesisTime) {
-		currentEpoch = 0
-	}
-	nextForkVersion, nextForkEpoch, err := forks.NextForkData(currentEpoch)
-	if err != nil {
-		return nil, err
-	}
+func updateENR(node *enode.LocalNode, entry, next params.NetworkScheduleEntry) error {
 	enrForkID := &pb.ENRForkID{
-		CurrentForkDigest: digest[:],
-		NextForkVersion:   nextForkVersion[:],
-		NextForkEpoch:     nextForkEpoch,
+		CurrentForkDigest: entry.ForkDigest[:],
+		NextForkVersion:   next.ForkVersion[:],
+		NextForkEpoch:     next.Epoch,
 	}
+	if entry.Epoch == next.Epoch {
+		enrForkID.NextForkEpoch = params.BeaconConfig().FarFutureEpoch
+	}
+	logFields := logrus.Fields{
+		"CurrentForkDigest": fmt.Sprintf("%#x", enrForkID.CurrentForkDigest),
+		"NextForkVersion":   fmt.Sprintf("%#x", enrForkID.NextForkVersion),
+		"NextForkEpoch":     fmt.Sprintf("%d", enrForkID.NextForkEpoch),
+	}
+	if params.BeaconConfig().FuluForkEpoch != params.BeaconConfig().FarFutureEpoch {
+		if entry.ForkDigest == next.ForkDigest {
+			node.Set(enr.WithEntry(nfdEnrKey, make([]byte, len(next.ForkDigest))))
+		} else {
+			node.Set(enr.WithEntry(nfdEnrKey, next.ForkDigest[:]))
+		}
+		logFields["NextForkDigest"] = fmt.Sprintf("%#x", next.ForkDigest)
+	}
+	log.WithFields(logFields).Info("Updating ENR Fork ID")
 	enc, err := enrForkID.MarshalSSZ()
 	if err != nil {
-		return nil, err
+		return err
 	}
-	forkEntry := enr.WithEntry(eth2ENRKey, enc)
+	forkEntry := enr.WithEntry(eth2EnrKey, enc)
 	node.Set(forkEntry)
-	return node, nil
+	return nil
 }
 
 // Retrieves an enrForkID from an ENR record by key lookup
 // under the Ethereum consensus EnrKey
 func forkEntry(record *enr.Record) (*pb.ENRForkID, error) {
 	sszEncodedForkEntry := make([]byte, 16)
-	entry := enr.WithEntry(eth2ENRKey, &sszEncodedForkEntry)
+	entry := enr.WithEntry(eth2EnrKey, &sszEncodedForkEntry)
 	err := record.Load(entry)
 	if err != nil {
 		return nil, err
@@ -126,3 +171,15 @@ func forkEntry(record *enr.Record) (*pb.ENRForkID, error) {
 	}
 	return forkEntry, nil
 }
+
+// nfd retrieves the value of the `nfd` ("next fork digest") key from an ENR record.
+func nfd(record *enr.Record) [4]byte {
+	digest := [4]byte{}
+	entry := enr.WithEntry(nfdEnrKey, &digest)
+	if err := record.Load(entry); err != nil {
+		// Treat a missing nfd entry as an empty digest.
+		// We do this to avoid errors when checking peers that have not upgraded for fulu.
+		return [4]byte{}
+	}
+	return digest
+}

beacon-chain/p2p/fork_test.go

@@ -8,254 +8,152 @@ import (
 	"testing"
 	"time"
 
-	mock "github.com/OffchainLabs/prysm/v6/beacon-chain/blockchain/testing"
-	"github.com/OffchainLabs/prysm/v6/beacon-chain/core/signing"
-	testDB "github.com/OffchainLabs/prysm/v6/beacon-chain/db/testing"
-	fieldparams "github.com/OffchainLabs/prysm/v6/config/fieldparams"
+	"github.com/OffchainLabs/prysm/v6/beacon-chain/startup"
 	"github.com/OffchainLabs/prysm/v6/config/params"
-	"github.com/OffchainLabs/prysm/v6/consensus-types/primitives"
-	"github.com/OffchainLabs/prysm/v6/encoding/bytesutil"
-	"github.com/OffchainLabs/prysm/v6/network/forks"
 	pb "github.com/OffchainLabs/prysm/v6/proto/prysm/v1alpha1"
 	"github.com/OffchainLabs/prysm/v6/testing/assert"
 	"github.com/OffchainLabs/prysm/v6/testing/require"
+	"github.com/ethereum/go-ethereum/common/hexutil"
 	"github.com/ethereum/go-ethereum/p2p/enode"
 	"github.com/ethereum/go-ethereum/p2p/enr"
-	ma "github.com/multiformats/go-multiaddr"
-	"github.com/sirupsen/logrus"
-	logTest "github.com/sirupsen/logrus/hooks/test"
 )
 
-func TestStartDiscv5_DifferentForkDigests(t *testing.T) {
-	const port = 2000
+func TestCompareForkENR(t *testing.T) {
+	params.SetupTestConfigCleanup(t)
+	params.BeaconConfig().FuluForkEpoch = params.BeaconConfig().ElectraForkEpoch + 4096
+	params.BeaconConfig().InitializeForkSchedule()
 
-	ipAddr, pkey := createAddrAndPrivKey(t)
-	genesisTime := time.Now()
-	genesisValidatorsRoot := make([]byte, fieldparams.RootLength)
-	db := testDB.SetupDB(t)
+	db, err := enode.OpenDB("")
+	assert.NoError(t, err)
+	_, k := createAddrAndPrivKey(t)
+	clock := startup.NewClock(time.Now(), params.BeaconConfig().GenesisValidatorsRoot)
+	current := params.GetNetworkScheduleEntry(clock.CurrentEpoch())
+	next := params.NextNetworkScheduleEntry(clock.CurrentEpoch())
+	self := enode.NewLocalNode(db, k)
+	require.NoError(t, updateENR(self, current, next))
 
-	s := &Service{
-		cfg: &Config{
-			UDPPort:              uint(port),
-			StateNotifier:        &mock.MockStateNotifier{},
-			PingInterval:         testPingInterval,
-			DisableLivenessCheck: true,
-			DB:                   db,
+	cases := []struct {
+		name      string
+		expectErr error
+		expectLog string
+		node      func(t *testing.T) *enode.Node
+	}{
+		{
+			name: "match",
+			node: func(t *testing.T) *enode.Node {
+				// Create a peer with the same current fork digest and next fork version/epoch.
+				peer := enode.NewLocalNode(db, k)
+				require.NoError(t, updateENR(peer, current, next))
+				return peer.Node()
+			},
+		},
+		{
+			name: "current digest mismatch",
+			node: func(t *testing.T) *enode.Node {
+				// Create a peer with the same current fork digest and next fork version/epoch.
+				peer := enode.NewLocalNode(db, k)
+				testDigest := [4]byte{0xFF, 0xFF, 0xFF, 0xFF}
+				require.NotEqual(t, current.ForkDigest, testDigest, "ensure test fork digest is unique")
+				currentCopy := current
+				currentCopy.ForkDigest = testDigest
+				require.NoError(t, updateENR(peer, currentCopy, next))
+				return peer.Node()
+			},
+			expectErr: errCurrentDigestMismatch,
+		},
+		{
+			name: "next_fork_epoch match, next_fork_version mismatch",
+			node: func(t *testing.T) *enode.Node {
+				// Create a peer with the same current fork digest and next fork version/epoch.
+				peer := enode.NewLocalNode(db, k)
+				testVersion := [4]byte{0xFF, 0xFF, 0xFF, 0xFF}
+				require.NotEqual(t, next.ForkVersion, testVersion, "ensure test fork version is unique")
+				nextCopy := next
+				nextCopy.ForkVersion = testVersion
+				require.NoError(t, updateENR(peer, current, nextCopy))
+				return peer.Node()
+			},
+			expectErr: errNextVersionMismatch,
+		},
+		{
+			name: "next fork epoch mismatch, next fork digest mismatch",
+			node: func(t *testing.T) *enode.Node {
+				// Create a peer with the same current fork digest and next fork version/epoch.
+				peer := enode.NewLocalNode(db, k)
+				nextCopy := next
+				// next epoch does not match, and neither does the next fork digest.
+				nextCopy.Epoch = nextCopy.Epoch + 1
+				nfd := [4]byte{0xFF, 0xFF, 0xFF, 0xFF}
+				require.NotEqual(t, next.ForkDigest, nfd)
+				//peer.Set(enr.WithEntry(nfdEnrKey, nfd[:]))
+				nextCopy.ForkDigest = nfd
+				require.NoError(t, updateENR(peer, current, nextCopy))
+				return peer.Node()
+			},
+			// no error because we allow a different next fork version / digest if the next fork epoch does not match
+		},
+		{
+			name: "next fork epoch -match-, next fork digest mismatch",
+			node: func(t *testing.T) *enode.Node {
+				peer := enode.NewLocalNode(db, k)
+				nextCopy := next
+				nfd := [4]byte{0xFF, 0xFF, 0xFF, 0xFF}
+				// next epoch *does match*, but the next fork digest doesn't - so we should get an error.
+				require.NotEqual(t, next.ForkDigest, nfd)
+				nextCopy.ForkDigest = nfd
+				//peer.Set(enr.WithEntry(nfdEnrKey, nfd[:]))
+				require.NoError(t, updateENR(peer, current, nextCopy))
+				return peer.Node()
+			},
+			expectErr: errNextDigestMismatch,
 		},
-		genesisTime:           genesisTime,
-		genesisValidatorsRoot: genesisValidatorsRoot,
-		custodyInfo:           &custodyInfo{},
-	}
-	bootListener, err := s.createListener(ipAddr, pkey)
-	require.NoError(t, err)
-	defer bootListener.Close()
-
-	// Allow bootnode's table to have its initial refresh. This allows
-	// inbound nodes to be added in.
-	time.Sleep(5 * time.Second)
-
-	bootNode := bootListener.Self()
-	cfg := &Config{
-		Discv5BootStrapAddrs: []string{bootNode.String()},
-		UDPPort:              uint(port),
-		StateNotifier:        &mock.MockStateNotifier{},
-		PingInterval:         testPingInterval,
-		DisableLivenessCheck: true,
-		DB:                   db,
 	}
 
-	var listeners []*listenerWrapper
-	for i := 1; i <= 5; i++ {
-		port := 3000 + i
-		cfg.UDPPort = uint(port)
-		ipAddr, pkey := createAddrAndPrivKey(t)
-
-		// We give every peer a different genesis validators root, which
-		// will cause each peer to have a different ForkDigest, preventing
-		// them from connecting according to our discovery rules for Ethereum consensus.
-		root := make([]byte, 32)
-		copy(root, strconv.Itoa(port))
-		s = &Service{
-			cfg:                   cfg,
-			genesisTime:           genesisTime,
-			genesisValidatorsRoot: root,
-			custodyInfo:           &custodyInfo{},
-		}
-		listener, err := s.startDiscoveryV5(ipAddr, pkey)
-		assert.NoError(t, err, "Could not start discovery for node")
-		listeners = append(listeners, listener)
+	for _, c := range cases {
+		t.Run(c.name, func(t *testing.T) {
+			peer := c.node(t)
+			err := compareForkENR(self.Node().Record(), peer.Record())
+			if c.expectErr != nil {
+				require.ErrorIs(t, err, c.expectErr, "Expected error to match")
+			} else {
+				require.NoError(t, err, "Expected no error comparing fork ENRs")
+			}
+		})
 	}
-	defer func() {
-		// Close down all peers.
-		for _, listener := range listeners {
-			listener.Close()
-		}
-	}()
-
-	// Wait for the nodes to have their local routing tables to be populated with the other nodes
-	time.Sleep(discoveryWaitTime)
-
-	lastListener := listeners[len(listeners)-1]
-	nodes := lastListener.Lookup(bootNode.ID())
-	if len(nodes) < 4 {
-		t.Errorf("The node's local table doesn't have the expected number of nodes. "+
-			"Expected more than or equal to %d but got %d", 4, len(nodes))
-	}
-
-	// Now, we start a new p2p service. It should have no peers aside from the
-	// bootnode given all nodes provided by discv5 will have different fork digests.
-	cfg.UDPPort = 14000
-	cfg.TCPPort = 14001
-	cfg.MaxPeers = 30
-	s, err = NewService(t.Context(), cfg)
-	require.NoError(t, err)
-	s.genesisTime = genesisTime
-	s.genesisValidatorsRoot = make([]byte, 32)
-	s.dv5Listener = lastListener
-
-	addrs := make([]ma.Multiaddr, 0)
-
-	for _, node := range nodes {
-		if s.filterPeer(node) {
-			nodeAddrs, err := retrieveMultiAddrsFromNode(node)
-			require.NoError(t, err)
-			addrs = append(addrs, nodeAddrs...)
-		}
-	}
-
-	// We should not have valid peers if the fork digest mismatched.
-	assert.Equal(t, 0, len(addrs), "Expected 0 valid peers")
-	require.NoError(t, s.Stop())
 }
 
-func TestStartDiscv5_SameForkDigests_DifferentNextForkData(t *testing.T) {
-	const port = 2000
-
+func TestNfdSetAndLoad(t *testing.T) {
 	params.SetupTestConfigCleanup(t)
-	hook := logTest.NewGlobal()
-	logrus.SetLevel(logrus.TraceLevel)
-	ipAddr, pkey := createAddrAndPrivKey(t)
-	genesisTime := time.Now()
-	genesisValidatorsRoot := make([]byte, 32)
-	db := testDB.SetupDB(t)
-
-	s := &Service{
-		cfg:                   &Config{UDPPort: uint(port), PingInterval: testPingInterval, DisableLivenessCheck: true, DB: db},
-		genesisTime:           genesisTime,
-		genesisValidatorsRoot: genesisValidatorsRoot,
-		custodyInfo:           &custodyInfo{},
-	}
-	bootListener, err := s.createListener(ipAddr, pkey)
-	require.NoError(t, err)
-	defer bootListener.Close()
-
-	// Allow bootnode's table to have its initial refresh. This allows
-	// inbound nodes to be added in.
-	time.Sleep(5 * time.Second)
-
-	bootNode := bootListener.Self()
-	cfg := &Config{
-		Discv5BootStrapAddrs: []string{bootNode.String()},
-		UDPPort:              uint(port),
-		PingInterval:         testPingInterval,
-		DisableLivenessCheck: true,
-		DB:                   db,
-	}
-
-	var listeners []*listenerWrapper
-	for i := 1; i <= 5; i++ {
-		port := 3000 + i
-		cfg.UDPPort = uint(port)
-		ipAddr, pkey := createAddrAndPrivKey(t)
-		c := params.BeaconConfig().Copy()
-		nextForkEpoch := primitives.Epoch(i)
-		c.ForkVersionSchedule[[4]byte{'A', 'B', 'C', 'D'}] = nextForkEpoch
-		params.OverrideBeaconConfig(c)
-
-		// We give every peer a different genesis validators root, which
-		// will cause each peer to have a different ForkDigest, preventing
-		// them from connecting according to our discovery rules for Ethereum consensus.
-		s = &Service{
-			cfg:                   cfg,
-			genesisTime:           genesisTime,
-			genesisValidatorsRoot: genesisValidatorsRoot,
-			custodyInfo:           &custodyInfo{},
-		}
-		listener, err := s.startDiscoveryV5(ipAddr, pkey)
-		assert.NoError(t, err, "Could not start discovery for node")
-		listeners = append(listeners, listener)
-	}
-	defer func() {
-		// Close down all peers.
-		for _, listener := range listeners {
-			listener.Close()
-		}
-	}()
-
-	// Wait for the nodes to have their local routing tables to be populated with the other nodes
-	time.Sleep(discoveryWaitTime)
-
-	lastListener := listeners[len(listeners)-1]
-	nodes := lastListener.Lookup(bootNode.ID())
-	if len(nodes) < 4 {
-		t.Errorf("The node's local table doesn't have the expected number of nodes. "+
-			"Expected more than or equal to %d but got %d", 4, len(nodes))
-	}
-
-	// Now, we start a new p2p service. It should have no peers aside from the
-	// bootnode given all nodes provided by discv5 will have different fork digests.
-	cfg.UDPPort = 14000
-	cfg.TCPPort = 14001
-	cfg.MaxPeers = 30
-	cfg.StateNotifier = &mock.MockStateNotifier{}
-	s, err = NewService(t.Context(), cfg)
-	require.NoError(t, err)
-
-	s.genesisTime = genesisTime
-	s.genesisValidatorsRoot = make([]byte, 32)
-	s.dv5Listener = lastListener
-	addrs := make([]ma.Multiaddr, 0, len(nodes))
-
-	for _, node := range nodes {
-		if s.filterPeer(node) {
-			nodeAddrs, err := retrieveMultiAddrsFromNode(node)
-			require.NoError(t, err)
-			addrs = append(addrs, nodeAddrs...)
-		}
-	}
-	if len(addrs) == 0 {
-		t.Error("Expected to have valid peers, got 0")
-	}
-
-	require.LogsContain(t, hook, "Peer matches fork digest but has different next fork epoch")
-	require.NoError(t, s.Stop())
+	params.BeaconConfig().FuluForkEpoch = params.BeaconConfig().ElectraForkEpoch + 4096
+	params.BeaconConfig().InitializeForkSchedule()
+	db, err := enode.OpenDB("")
+	assert.NoError(t, err)
+	_, k := createAddrAndPrivKey(t)
+	clock := startup.NewClock(time.Now(), params.BeaconConfig().GenesisValidatorsRoot)
+	current := params.GetNetworkScheduleEntry(clock.CurrentEpoch())
+	next := params.NextNetworkScheduleEntry(clock.CurrentEpoch())
+	next.ForkDigest = [4]byte{0xFF, 0xFF, 0xFF, 0xFF} // Ensure a unique digest for testing.
+	self := enode.NewLocalNode(db, k)
+	require.NoError(t, updateENR(self, current, next))
+	n := nfd(self.Node().Record())
+	assert.Equal(t, next.ForkDigest, n, "Expected nfd to match next fork digest")
 }
 
 func TestDiscv5_AddRetrieveForkEntryENR(t *testing.T) {
 	params.SetupTestConfigCleanup(t)
-	c := params.BeaconConfig().Copy()
-	c.ForkVersionSchedule = map[[4]byte]primitives.Epoch{
-		bytesutil.ToBytes4(params.BeaconConfig().GenesisForkVersion): 0,
-		{0, 0, 0, 1}: 1,
-	}
-	nextForkEpoch := primitives.Epoch(1)
-	nextForkVersion := []byte{0, 0, 0, 1}
-	params.OverrideBeaconConfig(c)
+	params.BeaconConfig().InitializeForkSchedule()
 
-	genesisTime := time.Now()
-	genesisValidatorsRoot := make([]byte, 32)
-	digest, err := forks.CreateForkDigest(genesisTime, make([]byte, 32))
-	require.NoError(t, err)
+	clock := startup.NewClock(time.Now(), params.BeaconConfig().GenesisValidatorsRoot)
+	current := params.GetNetworkScheduleEntry(clock.CurrentEpoch())
+	next := params.NextNetworkScheduleEntry(clock.CurrentEpoch())
 	enrForkID := &pb.ENRForkID{
-		CurrentForkDigest: digest[:],
-		NextForkVersion:   nextForkVersion,
-		NextForkEpoch:     nextForkEpoch,
+		CurrentForkDigest: current.ForkDigest[:],
+		NextForkVersion:   next.ForkVersion[:],
+		NextForkEpoch:     next.Epoch,
 	}
 	enc, err := enrForkID.MarshalSSZ()
 	require.NoError(t, err)
-	entry := enr.WithEntry(eth2ENRKey, enc)
-	// In epoch 1 of current time, the fork version should be
-	// {0, 0, 0, 1} according to the configuration override above.
+	entry := enr.WithEntry(eth2EnrKey, enc)
 	temp := t.TempDir()
 	randNum := rand.Int()
 	tempPath := path.Join(temp, strconv.Itoa(randNum))
@@ -267,18 +165,16 @@ func TestDiscv5_AddRetrieveForkEntryENR(t *testing.T) {
 	localNode := enode.NewLocalNode(db, pkey)
 	localNode.Set(entry)
 
-	want, err := signing.ComputeForkDigest([]byte{0, 0, 0, 0}, genesisValidatorsRoot)
-	require.NoError(t, err)
-
 	resp, err := forkEntry(localNode.Node().Record())
 	require.NoError(t, err)
-	assert.DeepEqual(t, want[:], resp.CurrentForkDigest)
-	assert.DeepEqual(t, nextForkVersion, resp.NextForkVersion)
-	assert.Equal(t, nextForkEpoch, resp.NextForkEpoch, "Unexpected next fork epoch")
+	assert.Equal(t, hexutil.Encode(current.ForkDigest[:]), hexutil.Encode(resp.CurrentForkDigest))
+	assert.Equal(t, hexutil.Encode(next.ForkVersion[:]), hexutil.Encode(resp.NextForkVersion))
+	assert.Equal(t, next.Epoch, resp.NextForkEpoch, "Unexpected next fork epoch")
 }
 
-func TestAddForkEntry_Genesis(t *testing.T) {
+func TestAddForkEntry_NextForkVersion(t *testing.T) {
 	params.SetupTestConfigCleanup(t)
+	params.BeaconConfig().InitializeForkSchedule()
 	temp := t.TempDir()
 	randNum := rand.Int()
 	tempPath := path.Join(temp, strconv.Itoa(randNum))
@@ -288,17 +184,135 @@ func TestAddForkEntry_Genesis(t *testing.T) {
 	db, err := enode.OpenDB("")
 	require.NoError(t, err)
 
-	bCfg := params.MainnetConfig()
-	bCfg.ForkVersionSchedule = map[[4]byte]primitives.Epoch{}
-	bCfg.ForkVersionSchedule[bytesutil.ToBytes4(params.BeaconConfig().GenesisForkVersion)] = bCfg.GenesisEpoch
-	params.OverrideBeaconConfig(bCfg)
-
 	localNode := enode.NewLocalNode(db, pkey)
-	localNode, err = addForkEntry(localNode, time.Now().Add(10*time.Second), bytesutil.PadTo([]byte{'A', 'B', 'C', 'D'}, 32))
+	clock := startup.NewClock(time.Now(), params.BeaconConfig().GenesisValidatorsRoot)
+	current := params.GetNetworkScheduleEntry(clock.CurrentEpoch())
+	next := params.NextNetworkScheduleEntry(clock.CurrentEpoch())
+	// Add the fork entry to the local node's ENR.
+	require.NoError(t, updateENR(localNode, current, next))
+	fe, err := forkEntry(localNode.Node().Record())
 	require.NoError(t, err)
-	forkEntry, err := forkEntry(localNode.Node().Record())
-	require.NoError(t, err)
-	assert.DeepEqual(t,
-		params.BeaconConfig().GenesisForkVersion, forkEntry.NextForkVersion,
+	assert.Equal(t,
+		hexutil.Encode(params.BeaconConfig().AltairForkVersion), hexutil.Encode(fe.NextForkVersion),
 		"Wanted Next Fork Version to be equal to genesis fork version")
+
+	last := params.LastForkEpoch()
+	current = params.GetNetworkScheduleEntry(last)
+	next = params.NextNetworkScheduleEntry(last)
+	require.NoError(t, updateENR(localNode, current, next))
+	entry := params.NextNetworkScheduleEntry(last)
+	fe, err = forkEntry(localNode.Node().Record())
+	require.NoError(t, err)
+	assert.Equal(t,
+		hexutil.Encode(entry.ForkVersion[:]), hexutil.Encode(fe.NextForkVersion),
+		"Wanted Next Fork Version to be equal to last entry in schedule")
+
+}
+
+func TestUpdateENR_FuluForkDigest(t *testing.T) {
+	setupTest := func(t *testing.T, fuluEnabled bool) (*enode.LocalNode, func()) {
+		params.SetupTestConfigCleanup(t)
+
+		cfg := params.BeaconConfig().Copy()
+		if fuluEnabled {
+			cfg.FuluForkEpoch = 100
+		} else {
+			cfg.FuluForkEpoch = cfg.FarFutureEpoch
+		}
+		cfg.FuluForkVersion = []byte{5, 0, 0, 0}
+		params.OverrideBeaconConfig(cfg)
+		cfg.InitializeForkSchedule()
+
+		pkey, err := privKey(&Config{DataDir: t.TempDir()})
+		require.NoError(t, err, "Could not get private key")
+		db, err := enode.OpenDB("")
+		require.NoError(t, err)
+
+		localNode := enode.NewLocalNode(db, pkey)
+		cleanup := func() {
+			db.Close()
+		}
+
+		return localNode, cleanup
+	}
+
+	tests := []struct {
+		name         string
+		fuluEnabled  bool
+		currentEntry params.NetworkScheduleEntry
+		nextEntry    params.NetworkScheduleEntry
+		validateNFD  func(t *testing.T, localNode *enode.LocalNode, nextEntry params.NetworkScheduleEntry)
+	}{
+		{
+			name:        "different digests sets nfd to next digest",
+			fuluEnabled: true,
+			currentEntry: params.NetworkScheduleEntry{
+				Epoch:       50,
+				ForkDigest:  [4]byte{1, 2, 3, 4},
+				ForkVersion: [4]byte{1, 0, 0, 0},
+			},
+			nextEntry: params.NetworkScheduleEntry{
+				Epoch:       100,
+				ForkDigest:  [4]byte{5, 6, 7, 8}, // Different from current
+				ForkVersion: [4]byte{2, 0, 0, 0},
+			},
+			validateNFD: func(t *testing.T, localNode *enode.LocalNode, nextEntry params.NetworkScheduleEntry) {
+				var nfdValue []byte
+				err := localNode.Node().Record().Load(enr.WithEntry(nfdEnrKey, &nfdValue))
+				require.NoError(t, err)
+				assert.DeepEqual(t, nextEntry.ForkDigest[:], nfdValue, "nfd entry should equal next fork digest")
+			},
+		},
+		{
+			name:        "same digests sets nfd to empty",
+			fuluEnabled: true,
+			currentEntry: params.NetworkScheduleEntry{
+				Epoch:       50,
+				ForkDigest:  [4]byte{1, 2, 3, 4},
+				ForkVersion: [4]byte{1, 0, 0, 0},
+			},
+			nextEntry: params.NetworkScheduleEntry{
+				Epoch:       100,
+				ForkDigest:  [4]byte{1, 2, 3, 4}, // Same as current
+				ForkVersion: [4]byte{2, 0, 0, 0},
+			},
+			validateNFD: func(t *testing.T, localNode *enode.LocalNode, nextEntry params.NetworkScheduleEntry) {
+				var nfdValue []byte
+				err := localNode.Node().Record().Load(enr.WithEntry(nfdEnrKey, &nfdValue))
+				require.NoError(t, err)
+				assert.DeepEqual(t, make([]byte, len(nextEntry.ForkDigest)), nfdValue, "nfd entry should be empty bytes when digests are same")
+			},
+		},
+		{
+			name:        "fulu disabled does not add nfd field",
+			fuluEnabled: false,
+			currentEntry: params.NetworkScheduleEntry{
+				Epoch:       50,
+				ForkDigest:  [4]byte{1, 2, 3, 4},
+				ForkVersion: [4]byte{1, 0, 0, 0},
+			},
+			nextEntry: params.NetworkScheduleEntry{
+				Epoch:       100,
+				ForkDigest:  [4]byte{5, 6, 7, 8}, // Different from current
+				ForkVersion: [4]byte{2, 0, 0, 0},
+			},
+			validateNFD: func(t *testing.T, localNode *enode.LocalNode, nextEntry params.NetworkScheduleEntry) {
+				var nfdValue []byte
+				err := localNode.Node().Record().Load(enr.WithEntry(nfdEnrKey, &nfdValue))
+				require.ErrorContains(t, "missing ENR key", err, "nfd field should not be present when Fulu fork is disabled")
+			},
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			localNode, cleanup := setupTest(t, tt.fuluEnabled)
+			defer cleanup()
+
+			currentEntry := tt.currentEntry
+			nextEntry := tt.nextEntry
+			require.NoError(t, updateENR(localNode, currentEntry, nextEntry))
+			tt.validateNFD(t, localNode, nextEntry)
+		})
+	}
 }

beacon-chain/p2p/fork_watcher.go

@@ -9,27 +9,26 @@ import (
 // updates the node's discovery service to reflect any new fork version
 // changes.
 func (s *Service) forkWatcher() {
+	// Exit early if discovery is disabled - there's no ENR to update
+	if s.dv5Listener == nil {
+		log.Debug("Discovery disabled, exiting fork watcher")
+		return
+	}
+
 	slotTicker := slots.NewSlotTicker(s.genesisTime, params.BeaconConfig().SecondsPerSlot)
+	var scheduleEntry params.NetworkScheduleEntry
 	for {
 		select {
 		case currSlot := <-slotTicker.C():
-			currEpoch := slots.ToEpoch(currSlot)
-			if currEpoch == params.BeaconConfig().AltairForkEpoch ||
-				currEpoch == params.BeaconConfig().BellatrixForkEpoch ||
-				currEpoch == params.BeaconConfig().CapellaForkEpoch ||
-				currEpoch == params.BeaconConfig().DenebForkEpoch ||
-				currEpoch == params.BeaconConfig().ElectraForkEpoch ||
-				currEpoch == params.BeaconConfig().FuluForkEpoch {
-				// If we are in the fork epoch, we update our enr with
-				// the updated fork digest. These repeatedly does
-				// this over the epoch, which might be slightly wasteful
-				// but is fine nonetheless.
-				if s.dv5Listener != nil { // make sure it's not a local network
-					_, err := addForkEntry(s.dv5Listener.LocalNode(), s.genesisTime, s.genesisValidatorsRoot)
-					if err != nil {
-						log.WithError(err).Error("Could not add fork entry")
-					}
+			currentEpoch := slots.ToEpoch(currSlot)
+			newEntry := params.GetNetworkScheduleEntry(currentEpoch)
+			if newEntry.ForkDigest != scheduleEntry.ForkDigest {
+				nextEntry := params.NextNetworkScheduleEntry(currentEpoch)
+				if err := updateENR(s.dv5Listener.LocalNode(), newEntry, nextEntry); err != nil {
+					log.WithFields(newEntry.LogFields()).WithError(err).Error("Could not add fork entry")
+					continue // don't replace scheduleEntry until this succeeds
 				}
+				scheduleEntry = newEntry
 			}
 		case <-s.ctx.Done():
 			log.Debug("Context closed, exiting goroutine")

beacon-chain/p2p/interfaces.go

@@ -51,7 +51,7 @@ type (
 		BroadcastBlob(ctx context.Context, subnet uint64, blob *ethpb.BlobSidecar) error
 		BroadcastLightClientOptimisticUpdate(ctx context.Context, update interfaces.LightClientOptimisticUpdate) error
 		BroadcastLightClientFinalityUpdate(ctx context.Context, update interfaces.LightClientFinalityUpdate) error
-		BroadcastDataColumn(root [fieldparams.RootLength]byte, columnSubnet uint64, dataColumnSidecar *ethpb.DataColumnSidecar) error
+		BroadcastDataColumnSidecar(root [fieldparams.RootLength]byte, columnSubnet uint64, dataColumnSidecar *ethpb.DataColumnSidecar) error
 	}
 
 	// SetStreamHandler configures p2p to handle streams of a certain topic ID.

beacon-chain/p2p/message_id.go

@@ -7,7 +7,6 @@ import (
 	"github.com/OffchainLabs/prysm/v6/crypto/hash"
 	"github.com/OffchainLabs/prysm/v6/encoding/bytesutil"
 	"github.com/OffchainLabs/prysm/v6/math"
-	"github.com/OffchainLabs/prysm/v6/network/forks"
 	pubsubpb "github.com/libp2p/go-libp2p-pubsub/pb"
 )
 
@@ -39,7 +38,7 @@ func MsgID(genesisValidatorsRoot []byte, pmsg *pubsubpb.Message) string {
 		copy(msg, "invalid")
 		return bytesutil.UnsafeCastToString(msg)
 	}
-	_, fEpoch, err := forks.RetrieveForkDataFromDigest(digest, genesisValidatorsRoot)
+	_, fEpoch, err := params.ForkDataFromDigest(digest)
 	if err != nil {
 		// Impossible condition that should
 		// never be hit.

beacon-chain/p2p/message_id_test.go

@@ -7,10 +7,10 @@ import (
 
 	"github.com/OffchainLabs/prysm/v6/beacon-chain/core/signing"
 	"github.com/OffchainLabs/prysm/v6/beacon-chain/p2p"
+	"github.com/OffchainLabs/prysm/v6/beacon-chain/startup"
 	"github.com/OffchainLabs/prysm/v6/config/params"
 	"github.com/OffchainLabs/prysm/v6/crypto/hash"
 	"github.com/OffchainLabs/prysm/v6/encoding/bytesutil"
-	"github.com/OffchainLabs/prysm/v6/network/forks"
 	"github.com/OffchainLabs/prysm/v6/testing/assert"
 	"github.com/golang/snappy"
 	pubsubpb "github.com/libp2p/go-libp2p-pubsub/pb"
@@ -18,28 +18,27 @@ import (
 
 func TestMsgID_HashesCorrectly(t *testing.T) {
 	params.SetupTestConfigCleanup(t)
-	genesisValidatorsRoot := bytesutil.PadTo([]byte{'A'}, 32)
-	d, err := forks.CreateForkDigest(time.Now(), genesisValidatorsRoot)
-	assert.NoError(t, err)
+	clock := startup.NewClock(time.Now(), bytesutil.ToBytes32([]byte{'A'}))
+	valRoot := clock.GenesisValidatorsRoot()
+	d := params.ForkDigest(clock.CurrentEpoch())
 	tpc := fmt.Sprintf(p2p.BlockSubnetTopicFormat, d)
 	invalidSnappy := [32]byte{'J', 'U', 'N', 'K'}
 	pMsg := &pubsubpb.Message{Data: invalidSnappy[:], Topic: &tpc}
 	hashedData := hash.Hash(append(params.BeaconConfig().MessageDomainInvalidSnappy[:], pMsg.Data...))
 	msgID := string(hashedData[:20])
-	assert.Equal(t, msgID, p2p.MsgID(genesisValidatorsRoot, pMsg), "Got incorrect msg id")
+	assert.Equal(t, msgID, p2p.MsgID(valRoot[:], pMsg), "Got incorrect msg id")
 
 	validObj := [32]byte{'v', 'a', 'l', 'i', 'd'}
 	enc := snappy.Encode(nil, validObj[:])
 	nMsg := &pubsubpb.Message{Data: enc, Topic: &tpc}
 	hashedData = hash.Hash(append(params.BeaconConfig().MessageDomainValidSnappy[:], validObj[:]...))
 	msgID = string(hashedData[:20])
-	assert.Equal(t, msgID, p2p.MsgID(genesisValidatorsRoot, nMsg), "Got incorrect msg id")
+	assert.Equal(t, msgID, p2p.MsgID(valRoot[:], nMsg), "Got incorrect msg id")
 }
 
 func TestMessageIDFunction_HashesCorrectlyAltair(t *testing.T) {
 	params.SetupTestConfigCleanup(t)
-	genesisValidatorsRoot := bytesutil.PadTo([]byte{'A'}, 32)
-	d, err := signing.ComputeForkDigest(params.BeaconConfig().AltairForkVersion, genesisValidatorsRoot)
+	d, err := signing.ComputeForkDigest(params.BeaconConfig().AltairForkVersion, params.BeaconConfig().GenesisValidatorsRoot[:])
 	assert.NoError(t, err)
 	tpc := fmt.Sprintf(p2p.BlockSubnetTopicFormat, d)
 	topicLen := uint64(len(tpc))
@@ -52,7 +51,7 @@ func TestMessageIDFunction_HashesCorrectlyAltair(t *testing.T) {
 	combinedObj = append(combinedObj, pMsg.Data...)
 	hashedData := hash.Hash(combinedObj)
 	msgID := string(hashedData[:20])
-	assert.Equal(t, msgID, p2p.MsgID(genesisValidatorsRoot, pMsg), "Got incorrect msg id")
+	assert.Equal(t, msgID, p2p.MsgID(params.BeaconConfig().GenesisValidatorsRoot[:], pMsg), "Got incorrect msg id")
 
 	validObj := [32]byte{'v', 'a', 'l', 'i', 'd'}
 	enc := snappy.Encode(nil, validObj[:])
@@ -63,13 +62,12 @@ func TestMessageIDFunction_HashesCorrectlyAltair(t *testing.T) {
 	combinedObj = append(combinedObj, validObj[:]...)
 	hashedData = hash.Hash(combinedObj)
 	msgID = string(hashedData[:20])
-	assert.Equal(t, msgID, p2p.MsgID(genesisValidatorsRoot, nMsg), "Got incorrect msg id")
+	assert.Equal(t, msgID, p2p.MsgID(params.BeaconConfig().GenesisValidatorsRoot[:], nMsg), "Got incorrect msg id")
 }
 
 func TestMessageIDFunction_HashesCorrectlyBellatrix(t *testing.T) {
 	params.SetupTestConfigCleanup(t)
-	genesisValidatorsRoot := bytesutil.PadTo([]byte{'A'}, 32)
-	d, err := signing.ComputeForkDigest(params.BeaconConfig().BellatrixForkVersion, genesisValidatorsRoot)
+	d, err := signing.ComputeForkDigest(params.BeaconConfig().BellatrixForkVersion, params.BeaconConfig().GenesisValidatorsRoot[:])
 	assert.NoError(t, err)
 	tpc := fmt.Sprintf(p2p.BlockSubnetTopicFormat, d)
 	topicLen := uint64(len(tpc))
@@ -82,7 +80,7 @@ func TestMessageIDFunction_HashesCorrectlyBellatrix(t *testing.T) {
 	combinedObj = append(combinedObj, pMsg.Data...)
 	hashedData := hash.Hash(combinedObj)
 	msgID := string(hashedData[:20])
-	assert.Equal(t, msgID, p2p.MsgID(genesisValidatorsRoot, pMsg), "Got incorrect msg id")
+	assert.Equal(t, msgID, p2p.MsgID(params.BeaconConfig().GenesisValidatorsRoot[:], pMsg), "Got incorrect msg id")
 
 	validObj := [32]byte{'v', 'a', 'l', 'i', 'd'}
 	enc := snappy.Encode(nil, validObj[:])
@@ -93,7 +91,7 @@ func TestMessageIDFunction_HashesCorrectlyBellatrix(t *testing.T) {
 	combinedObj = append(combinedObj, validObj[:]...)
 	hashedData = hash.Hash(combinedObj)
 	msgID = string(hashedData[:20])
-	assert.Equal(t, msgID, p2p.MsgID(genesisValidatorsRoot, nMsg), "Got incorrect msg id")
+	assert.Equal(t, msgID, p2p.MsgID(params.BeaconConfig().GenesisValidatorsRoot[:], nMsg), "Got incorrect msg id")
 }
 
 func TestMsgID_WithNilTopic(t *testing.T) {

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/pubsub.go

@@ -40,7 +40,7 @@ const (
 	rSubD = 8 // random gossip target
 )
 
-var errInvalidTopic = errors.New("invalid topic format")
+var ErrInvalidTopic = errors.New("invalid topic format")
 
 // Specifies the fixed size context length.
 const digestLength = 4
@@ -219,12 +219,12 @@ func convertTopicScores(topicMap map[string]*pubsub.TopicScoreSnapshot) map[stri
 func ExtractGossipDigest(topic string) ([4]byte, error) {
 	// Ensure the topic prefix is correct.
 	if len(topic) < len(gossipTopicPrefix)+1 || topic[:len(gossipTopicPrefix)] != gossipTopicPrefix {
-		return [4]byte{}, errInvalidTopic
+		return [4]byte{}, ErrInvalidTopic
 	}
 	start := len(gossipTopicPrefix)
 	end := strings.Index(topic[start:], "/")
 	if end == -1 { // Ensure a topic suffix exists.
-		return [4]byte{}, errInvalidTopic
+		return [4]byte{}, ErrInvalidTopic
 	}
 	end += start
 	strDigest := topic[start:end]

beacon-chain/p2p/pubsub_filter.go

@@ -1,15 +1,16 @@
 package p2p
 
 import (
+	"encoding/hex"
 	"fmt"
 	"strings"
 
 	"github.com/OffchainLabs/prysm/v6/beacon-chain/p2p/encoder"
 	"github.com/OffchainLabs/prysm/v6/config/params"
-	"github.com/OffchainLabs/prysm/v6/network/forks"
 	pubsub "github.com/libp2p/go-libp2p-pubsub"
 	pubsubpb "github.com/libp2p/go-libp2p-pubsub/pb"
 	"github.com/libp2p/go-libp2p/core/peer"
+	"github.com/pkg/errors"
 	"github.com/sirupsen/logrus"
 )
 
@@ -32,81 +33,76 @@ var _ pubsub.SubscriptionFilter = (*Service)(nil)
 // (Note: BlobSidecar is not included in this list since it is superseded by DataColumnSidecar)
 const pubsubSubscriptionRequestLimit = 500
 
+func (s *Service) setAllForkDigests() {
+	entries := params.SortedNetworkScheduleEntries()
+	s.allForkDigests = make(map[[4]byte]struct{}, len(entries))
+	for _, entry := range entries {
+		s.allForkDigests[entry.ForkDigest] = struct{}{}
+	}
+}
+
+var (
+	errNotReadyToSubscribe         = fmt.Errorf("not ready to subscribe, service is not initialized")
+	errMissingLeadingSlash         = fmt.Errorf("topic is missing leading slash")
+	errTopicMissingProtocolVersion = fmt.Errorf("topic is missing protocol version (eth2)")
+	errTopicPathWrongPartCount     = fmt.Errorf("topic path has wrong part count")
+	errDigestInvalid               = fmt.Errorf("digest is invalid")
+	errDigestUnexpected            = fmt.Errorf("digest is unexpected")
+	errSnappySuffixMissing         = fmt.Errorf("snappy suffix is missing")
+	errTopicNotFound               = fmt.Errorf("topic not found in gossip topic mappings")
+)
+
 // CanSubscribe returns true if the topic is of interest and we could subscribe to it.
 func (s *Service) CanSubscribe(topic string) bool {
-	if !s.isInitialized() {
+	if err := s.checkSubscribable(topic); err != nil {
+		if !errors.Is(err, errNotReadyToSubscribe) {
+			logrus.WithError(err).WithField("topic", topic).Debug("CanSubscribe failed")
+		}
 		return false
 	}
+	return true
+}
+
+func (s *Service) checkSubscribable(topic string) error {
+	if !s.isInitialized() {
+		return errNotReadyToSubscribe
+	}
 	parts := strings.Split(topic, "/")
 	if len(parts) != 5 {
-		return false
+		return errTopicPathWrongPartCount
 	}
 	// The topic must start with a slash, which means the first part will be empty.
 	if parts[0] != "" {
-		return false
+		return errMissingLeadingSlash
 	}
-	if parts[1] != "eth2" {
-		return false
+	protocol, rawDigest, suffix := parts[1], parts[2], parts[4]
+	if protocol != "eth2" {
+		return errTopicMissingProtocolVersion
 	}
-	phase0ForkDigest, err := s.currentForkDigest()
-	if err != nil {
-		log.WithError(err).Error("Could not determine fork digest")
-		return false
-	}
-	altairForkDigest, err := forks.ForkDigestFromEpoch(params.BeaconConfig().AltairForkEpoch, s.genesisValidatorsRoot)
-	if err != nil {
-		log.WithError(err).Error("Could not determine altair fork digest")
-		return false
-	}
-	bellatrixForkDigest, err := forks.ForkDigestFromEpoch(params.BeaconConfig().BellatrixForkEpoch, s.genesisValidatorsRoot)
-	if err != nil {
-		log.WithError(err).Error("Could not determine Bellatrix fork digest")
-		return false
-	}
-	capellaForkDigest, err := forks.ForkDigestFromEpoch(params.BeaconConfig().CapellaForkEpoch, s.genesisValidatorsRoot)
-	if err != nil {
-		log.WithError(err).Error("Could not determine Capella fork digest")
-		return false
-	}
-	denebForkDigest, err := forks.ForkDigestFromEpoch(params.BeaconConfig().DenebForkEpoch, s.genesisValidatorsRoot)
-	if err != nil {
-		log.WithError(err).Error("Could not determine Deneb fork digest")
-		return false
-	}
-	electraForkDigest, err := forks.ForkDigestFromEpoch(params.BeaconConfig().ElectraForkEpoch, s.genesisValidatorsRoot)
-	if err != nil {
-		log.WithError(err).Error("Could not determine Electra fork digest")
-		return false
-	}
-	fuluForkDigest, err := forks.ForkDigestFromEpoch(params.BeaconConfig().FuluForkEpoch, s.genesisValidatorsRoot)
-	if err != nil {
-		log.WithError(err).Error("Could not determine Fulu fork digest")
-		return false
-	}
-	switch parts[2] {
-	case fmt.Sprintf("%x", phase0ForkDigest):
-	case fmt.Sprintf("%x", altairForkDigest):
-	case fmt.Sprintf("%x", bellatrixForkDigest):
-	case fmt.Sprintf("%x", capellaForkDigest):
-	case fmt.Sprintf("%x", denebForkDigest):
-	case fmt.Sprintf("%x", electraForkDigest):
-	case fmt.Sprintf("%x", fuluForkDigest):
-	default:
-		return false
+	if suffix != encoder.ProtocolSuffixSSZSnappy {
+		return errSnappySuffixMissing
 	}
 
-	if parts[4] != encoder.ProtocolSuffixSSZSnappy {
-		return false
+	var digest [4]byte
+	dl, err := hex.Decode(digest[:], []byte(rawDigest))
+	if err != nil {
+		return errors.Wrapf(errDigestInvalid, "%v", err)
+	}
+	if dl != 4 {
+		return errors.Wrapf(errDigestInvalid, "wrong byte length")
+	}
+	if _, ok := s.allForkDigests[digest]; !ok {
+		return errDigestUnexpected
 	}
 
 	// Check the incoming topic matches any topic mapping. This includes a check for part[3].
 	for gt := range gossipTopicMappings {
 		if _, err := scanfcheck(strings.Join(parts[0:4], "/"), gt); err == nil {
-			return true
+			return nil
 		}
 	}
 
-	return false
+	return errTopicNotFound
 }
 
 // FilterIncomingSubscriptions is invoked for all RPCs containing subscription notifications.
@@ -124,7 +120,22 @@ func (s *Service) FilterIncomingSubscriptions(peerID peer.ID, subs []*pubsubpb.R
 		return nil, pubsub.ErrTooManySubscriptions
 	}
 
-	return pubsub.FilterSubscriptions(subs, s.CanSubscribe), nil
+	return pubsub.FilterSubscriptions(subs, s.logCheckSubscribableError(peerID)), nil
+}
+
+func (s *Service) logCheckSubscribableError(pid peer.ID) func(string) bool {
+	return func(topic string) bool {
+		if err := s.checkSubscribable(topic); err != nil {
+			if !errors.Is(err, errNotReadyToSubscribe) {
+				log.WithError(err).WithFields(logrus.Fields{
+					"peerID": pid,
+					"topic":  topic,
+				}).Debug("Peer subscription rejected")
+			}
+			return false
+		}
+		return true
+	}
 }
 
 // scanfcheck uses fmt.Sscanf to check that a given string matches expected format. This method

beacon-chain/p2p/pubsub_filter_test.go

@@ -12,8 +12,6 @@ import (
 	"github.com/OffchainLabs/prysm/v6/beacon-chain/startup"
 	"github.com/OffchainLabs/prysm/v6/config/params"
 	"github.com/OffchainLabs/prysm/v6/encoding/bytesutil"
-	"github.com/OffchainLabs/prysm/v6/network/forks"
-	"github.com/OffchainLabs/prysm/v6/testing/assert"
 	"github.com/OffchainLabs/prysm/v6/testing/require"
 	prysmTime "github.com/OffchainLabs/prysm/v6/time"
 	pubsubpb "github.com/libp2p/go-libp2p-pubsub/pb"
@@ -22,12 +20,11 @@ import (
 
 func TestService_CanSubscribe(t *testing.T) {
 	params.SetupTestConfigCleanup(t)
-	currentFork := [4]byte{0x01, 0x02, 0x03, 0x04}
+	params.BeaconConfig().InitializeForkSchedule()
 	validProtocolSuffix := "/" + encoder.ProtocolSuffixSSZSnappy
-	genesisTime := time.Now()
-	var valRoot [32]byte
-	digest, err := forks.CreateForkDigest(genesisTime, valRoot[:])
-	assert.NoError(t, err)
+	clock := startup.NewClock(time.Now(), params.BeaconConfig().GenesisValidatorsRoot)
+	currentFork := params.GetNetworkScheduleEntry(clock.CurrentEpoch()).ForkDigest
+	digest := params.ForkDigest(clock.CurrentEpoch())
 	type test struct {
 		name  string
 		topic string
@@ -109,12 +106,14 @@ func TestService_CanSubscribe(t *testing.T) {
 		}
 		tests = append(tests, tt)
 	}
+	valRoot := clock.GenesisValidatorsRoot()
 	for _, tt := range tests {
 		t.Run(tt.name, func(t *testing.T) {
 			s := &Service{
 				genesisValidatorsRoot: valRoot[:],
-				genesisTime:           genesisTime,
+				genesisTime:           clock.GenesisTime(),
 			}
+			s.setAllForkDigests()
 			if got := s.CanSubscribe(tt.topic); got != tt.want {
 				t.Errorf("CanSubscribe(%s) = %v, want %v", tt.topic, got, tt.want)
 			}
@@ -220,11 +219,10 @@ func TestGossipTopicMapping_scanfcheck_GossipTopicFormattingSanityCheck(t *testi
 
 func TestService_FilterIncomingSubscriptions(t *testing.T) {
 	params.SetupTestConfigCleanup(t)
+	params.BeaconConfig().InitializeForkSchedule()
+	clock := startup.NewClock(time.Now(), params.BeaconConfig().GenesisValidatorsRoot)
+	digest := params.ForkDigest(clock.CurrentEpoch())
 	validProtocolSuffix := "/" + encoder.ProtocolSuffixSSZSnappy
-	genesisTime := time.Now()
-	var valRoot [32]byte
-	digest, err := forks.CreateForkDigest(genesisTime, valRoot[:])
-	assert.NoError(t, err)
 	type args struct {
 		id   peer.ID
 		subs []*pubsubpb.RPC_SubOpts
@@ -321,12 +319,14 @@ func TestService_FilterIncomingSubscriptions(t *testing.T) {
 			},
 		},
 	}
+	valRoot := clock.GenesisValidatorsRoot()
 	for _, tt := range tests {
 		t.Run(tt.name, func(t *testing.T) {
 			s := &Service{
 				genesisValidatorsRoot: valRoot[:],
-				genesisTime:           genesisTime,
+				genesisTime:           clock.GenesisTime(),
 			}
+			s.setAllForkDigests()
 			got, err := s.FilterIncomingSubscriptions(tt.args.id, tt.args.subs)
 			if (err != nil) != tt.wantErr {
 				t.Errorf("FilterIncomingSubscriptions() error = %v, wantErr %v", err, tt.wantErr)

beacon-chain/p2p/rpc_topic_mappings.go

@@ -169,7 +169,7 @@ var (
 		RPCDataColumnSidecarsByRangeTopicV1: new(pb.DataColumnSidecarsByRangeRequest),
 
 		// DataColumnSidecarsByRoot v1 Message
-		RPCDataColumnSidecarsByRootTopicV1: new(p2ptypes.DataColumnsByRootIdentifiers),
+		RPCDataColumnSidecarsByRootTopicV1: p2ptypes.DataColumnsByRootIdentifiers{},
 	}
 
 	// Maps all registered protocol prefixes.

beacon-chain/p2p/service.go

@@ -14,6 +14,7 @@ import (
 	"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/p2p/types"
+	"github.com/OffchainLabs/prysm/v6/beacon-chain/startup"
 	"github.com/OffchainLabs/prysm/v6/config/features"
 	"github.com/OffchainLabs/prysm/v6/config/params"
 	"github.com/OffchainLabs/prysm/v6/consensus-types/primitives"
@@ -63,42 +64,42 @@ var (
 )
 
 // Service for managing peer to peer (p2p) networking.
-type (
-	Service struct {
-		started               bool
-		isPreGenesis          bool
-		pingMethod            func(ctx context.Context, id peer.ID) error
-		pingMethodLock        sync.RWMutex
-		cancel                context.CancelFunc
-		cfg                   *Config
-		peers                 *peers.Status
-		addrFilter            *multiaddr.Filters
-		ipLimiter             *leakybucket.Collector
-		privKey               *ecdsa.PrivateKey
-		metaData              metadata.Metadata
-		pubsub                *pubsub.PubSub
-		joinedTopics          map[string]*pubsub.Topic
-		joinedTopicsLock      sync.RWMutex
-		subnetsLock           map[uint64]*sync.RWMutex
-		subnetsLockLock       sync.Mutex // Lock access to subnetsLock
-		initializationLock    sync.Mutex
-		dv5Listener           ListenerRebooter
-		startupErr            error
-		ctx                   context.Context
-		host                  host.Host
-		genesisTime           time.Time
-		genesisValidatorsRoot []byte
-		activeValidatorCount  uint64
-		peerDisconnectionTime *cache.Cache
-		custodyInfo           *custodyInfo
-		custodyInfoLock       sync.RWMutex // Lock access to custodyInfo
-	}
+type Service struct {
+	started               bool
+	isPreGenesis          bool
+	pingMethod            func(ctx context.Context, id peer.ID) error
+	pingMethodLock        sync.RWMutex
+	cancel                context.CancelFunc
+	cfg                   *Config
+	peers                 *peers.Status
+	addrFilter            *multiaddr.Filters
+	ipLimiter             *leakybucket.Collector
+	privKey               *ecdsa.PrivateKey
+	metaData              metadata.Metadata
+	pubsub                *pubsub.PubSub
+	joinedTopics          map[string]*pubsub.Topic
+	joinedTopicsLock      sync.RWMutex
+	subnetsLock           map[uint64]*sync.RWMutex
+	subnetsLockLock       sync.Mutex // Lock access to subnetsLock
+	initializationLock    sync.Mutex
+	dv5Listener           ListenerRebooter
+	startupErr            error
+	ctx                   context.Context
+	host                  host.Host
+	genesisTime           time.Time
+	genesisValidatorsRoot []byte
+	activeValidatorCount  uint64
+	peerDisconnectionTime *cache.Cache
+	custodyInfo           *custodyInfo
+	custodyInfoLock       sync.RWMutex // Lock access to custodyInfo
+	clock                 *startup.Clock
+	allForkDigests        map[[4]byte]struct{}
+}
 
-	custodyInfo struct {
-		earliestAvailableSlot primitives.Slot
-		groupCount            uint64
-	}
-)
+type custodyInfo struct {
+	earliestAvailableSlot primitives.Slot
+	groupCount            uint64
+}
 
 // NewService initializes a new p2p service compatible with shared.Service interface. No
 // connections are made until the Start function is called during the service registry startup.
@@ -202,6 +203,7 @@ func (s *Service) Start() {
 	// Waits until the state is initialized via an event feed.
 	// Used for fork-related data when connecting peers.
 	s.awaitStateInitialized()
+	s.setAllForkDigests()
 	s.isPreGenesis = false
 
 	var relayNodes []string
@@ -455,7 +457,7 @@ func (s *Service) awaitStateInitialized() {
 	s.genesisTime = clock.GenesisTime()
 	gvr := clock.GenesisValidatorsRoot()
 	s.genesisValidatorsRoot = gvr[:]
-	_, err = s.currentForkDigest() // initialize fork digest cache
+	_, err = s.currentForkDigest()
 	if err != nil {
 		log.WithError(err).Error("Could not initialize fork digest")
 	}

beacon-chain/p2p/service_test.go

@@ -13,15 +13,13 @@ import (
 	"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"
+	testp2p "github.com/OffchainLabs/prysm/v6/beacon-chain/p2p/testing"
 	"github.com/OffchainLabs/prysm/v6/beacon-chain/startup"
 	fieldparams "github.com/OffchainLabs/prysm/v6/config/fieldparams"
 	"github.com/OffchainLabs/prysm/v6/config/params"
-	"github.com/OffchainLabs/prysm/v6/encoding/bytesutil"
-	"github.com/OffchainLabs/prysm/v6/network/forks"
 	"github.com/OffchainLabs/prysm/v6/testing/assert"
 	"github.com/OffchainLabs/prysm/v6/testing/require"
 	prysmTime "github.com/OffchainLabs/prysm/v6/time"
-	"github.com/ethereum/go-ethereum/p2p/enode"
 	"github.com/libp2p/go-libp2p"
 	"github.com/libp2p/go-libp2p/core/host"
 	"github.com/libp2p/go-libp2p/core/peer"
@@ -32,48 +30,6 @@ import (
 
 const testPingInterval = 100 * time.Millisecond
 
-type mockListener struct {
-	localNode *enode.LocalNode
-}
-
-func (m mockListener) Self() *enode.Node {
-	return m.localNode.Node()
-}
-
-func (mockListener) Close() {
-	// no-op
-}
-
-func (mockListener) Lookup(enode.ID) []*enode.Node {
-	panic("implement me")
-}
-
-func (mockListener) ReadRandomNodes(_ []*enode.Node) int {
-	panic("implement me")
-}
-
-func (mockListener) Resolve(*enode.Node) *enode.Node {
-	panic("implement me")
-}
-
-func (mockListener) Ping(*enode.Node) error {
-	panic("implement me")
-}
-
-func (mockListener) RequestENR(*enode.Node) (*enode.Node, error) {
-	panic("implement me")
-}
-
-func (mockListener) LocalNode() *enode.LocalNode {
-	panic("implement me")
-}
-
-func (mockListener) RandomNodes() enode.Iterator {
-	panic("implement me")
-}
-
-func (mockListener) RebootListener() error { panic("implement me") }
-
 func createHost(t *testing.T, port uint) (host.Host, *ecdsa.PrivateKey, net.IP) {
 	_, pkey := createAddrAndPrivKey(t)
 	ipAddr := net.ParseIP("127.0.0.1")
@@ -89,7 +45,7 @@ func TestService_Stop_SetsStartedToFalse(t *testing.T) {
 	s, err := NewService(t.Context(), &Config{StateNotifier: &mock.MockStateNotifier{}, DB: testDB.SetupDB(t)})
 	require.NoError(t, err)
 	s.started = true
-	s.dv5Listener = &mockListener{}
+	s.dv5Listener = testp2p.NewMockListener(nil, nil)
 	assert.NoError(t, s.Stop())
 	assert.Equal(t, false, s.started)
 }
@@ -115,7 +71,7 @@ func TestService_Start_OnlyStartsOnce(t *testing.T) {
 	}
 	s, err := NewService(t.Context(), cfg)
 	require.NoError(t, err)
-	s.dv5Listener = &mockListener{}
+	s.dv5Listener = testp2p.NewMockListener(nil, nil)
 	s.custodyInfo = &custodyInfo{}
 	exitRoutine := make(chan bool)
 	go func() {
@@ -135,14 +91,14 @@ func TestService_Start_OnlyStartsOnce(t *testing.T) {
 func TestService_Status_NotRunning(t *testing.T) {
 	params.SetupTestConfigCleanup(t)
 	s := &Service{started: false}
-	s.dv5Listener = &mockListener{}
+	s.dv5Listener = testp2p.NewMockListener(nil, nil)
 	assert.ErrorContains(t, "not running", s.Status(), "Status returned wrong error")
 }
 
 func TestService_Status_NoGenesisTimeSet(t *testing.T) {
 	params.SetupTestConfigCleanup(t)
 	s := &Service{started: true}
-	s.dv5Listener = &mockListener{}
+	s.dv5Listener = testp2p.NewMockListener(nil, nil)
 	assert.ErrorContains(t, "no genesis time set", s.Status(), "Status returned wrong error")
 
 	s.genesisTime = time.Now()
@@ -346,14 +302,16 @@ func TestPeer_Disconnect(t *testing.T) {
 
 func TestService_JoinLeaveTopic(t *testing.T) {
 	params.SetupTestConfigCleanup(t)
+	params.BeaconConfig().InitializeForkSchedule()
 	ctx, cancel := context.WithTimeout(t.Context(), 3*time.Second)
 	defer cancel()
 	gs := startup.NewClockSynchronizer()
 	s, err := NewService(ctx, &Config{StateNotifier: &mock.MockStateNotifier{}, ClockWaiter: gs, DB: testDB.SetupDB(t)})
 	require.NoError(t, err)
 
-	go s.awaitStateInitialized()
 	fd := initializeStateWithForkDigest(ctx, t, gs)
+	s.setAllForkDigests()
+	s.awaitStateInitialized()
 
 	assert.Equal(t, 0, len(s.joinedTopics))
 
@@ -382,15 +340,13 @@ func TestService_JoinLeaveTopic(t *testing.T) {
 // digest associated with that genesis event.
 func initializeStateWithForkDigest(_ context.Context, t *testing.T, gs startup.ClockSetter) [4]byte {
 	gt := prysmTime.Now()
-	gvr := bytesutil.ToBytes32(bytesutil.PadTo([]byte("genesis validators root"), 32))
-	require.NoError(t, gs.SetClock(startup.NewClock(gt, gvr)))
-
-	fd, err := forks.CreateForkDigest(gt, gvr[:])
-	require.NoError(t, err)
+	gvr := params.BeaconConfig().GenesisValidatorsRoot
+	clock := startup.NewClock(gt, gvr)
+	require.NoError(t, gs.SetClock(clock))
 
 	time.Sleep(50 * time.Millisecond) // wait for pubsub filter to initialize.
 
-	return fd
+	return params.ForkDigest(clock.CurrentEpoch())
 }
 
 func TestService_connectWithPeer(t *testing.T) {

beacon-chain/p2p/subnets.go

@@ -134,6 +134,24 @@ func (s *Service) FindAndDialPeersWithSubnets(
 	return nil
 }
 
+// updateDefectiveSubnets updates the defective subnets map when a node with matching subnets is found.
+// It decrements the defective count for each subnet the node satisfies and removes subnets
+// that are fully satisfied (count reaches 0).
+func updateDefectiveSubnets(
+	nodeSubnets map[uint64]bool,
+	defectiveSubnets map[uint64]int,
+) {
+	for subnet := range defectiveSubnets {
+		if !nodeSubnets[subnet] {
+			continue
+		}
+		defectiveSubnets[subnet]--
+		if defectiveSubnets[subnet] == 0 {
+			delete(defectiveSubnets, subnet)
+		}
+	}
+}
+
 // findPeersWithSubnets finds peers subscribed to defective subnets in batches
 // until enough peers are found or the context is canceled.
 // It returns new peers found during the search.
@@ -169,6 +187,7 @@ func (s *Service) findPeersWithSubnets(
 
 	// Crawl the network for peers subscribed to the defective subnets.
 	nodeByNodeID := make(map[enode.ID]*enode.Node)
+
 	for len(defectiveSubnets) > 0 && iterator.Next() {
 		if err := ctx.Err(); err != nil {
 			// Convert the map to a slice.
@@ -180,14 +199,28 @@ func (s *Service) findPeersWithSubnets(
 			return peersToDial, err
 		}
 
-		// Get all needed subnets that the node is subscribed to.
-		// Skip nodes that are not subscribed to any of the defective subnets.
 		node := iterator.Node()
 
+		// Remove duplicates, keeping the node with higher seq.
+		existing, ok := nodeByNodeID[node.ID()]
+		if ok && existing.Seq() >= node.Seq() {
+			continue // keep existing and skip.
+		}
+
+		// Treat nodes that exist in nodeByNodeID with higher seq numbers as new peers
+		// Skip peer not matching the filter.
 		if !s.filterPeer(node) {
+			if ok {
+				// this means the existing peer with the lower sequence number is no longer valid
+				delete(nodeByNodeID, existing.ID())
+				// Note: We are choosing to not rollback changes to the defective subnets map in favor of calling s.defectiveSubnets once again after dialing peers.
+				// This is a case that should rarely happen and should be handled through a second iteration in FindAndDialPeersWithSubnets
+			}
 			continue
 		}
 
+		// Get all needed subnets that the node is subscribed to.
+		// Skip nodes that are not subscribed to any of the defective subnets.
 		nodeSubnets, err := filter(node)
 		if err != nil {
 			return nil, errors.Wrap(err, "filter node")
@@ -196,30 +229,14 @@ func (s *Service) findPeersWithSubnets(
 			continue
 		}
 
-		// Remove duplicates, keeping the node with higher seq.
-		existing, ok := nodeByNodeID[node.ID()]
-		if ok && existing.Seq() > node.Seq() {
-			continue
-		}
-		nodeByNodeID[node.ID()] = node
-
 		// We found a new peer. Modify the defective subnets map
 		// and the filter accordingly.
-		for subnet := range defectiveSubnets {
-			if !nodeSubnets[subnet] {
-				continue
-			}
+		nodeByNodeID[node.ID()] = node
 
-			defectiveSubnets[subnet]--
-
-			if defectiveSubnets[subnet] == 0 {
-				delete(defectiveSubnets, subnet)
-			}
-
-			filter, err = s.nodeFilter(topicFormat, defectiveSubnets)
-			if err != nil {
-				return nil, errors.Wrap(err, "node filter")
-			}
+		updateDefectiveSubnets(nodeSubnets, defectiveSubnets)
+		filter, err = s.nodeFilter(topicFormat, defectiveSubnets)
+		if err != nil {
+			return nil, errors.Wrap(err, "node filter")
 		}
 	}
 

beacon-chain/p2p/subnets_test.go

@@ -3,7 +3,6 @@ package p2p
 import (
 	"context"
 	"crypto/rand"
-	"encoding/hex"
 	"fmt"
 	"testing"
 	"time"
@@ -11,14 +10,19 @@ import (
 	"github.com/OffchainLabs/prysm/v6/beacon-chain/cache"
 	"github.com/OffchainLabs/prysm/v6/beacon-chain/core/peerdas"
 	testDB "github.com/OffchainLabs/prysm/v6/beacon-chain/db/testing"
+	"github.com/OffchainLabs/prysm/v6/beacon-chain/p2p/peers"
+	"github.com/OffchainLabs/prysm/v6/beacon-chain/p2p/peers/scorers"
+	testp2p "github.com/OffchainLabs/prysm/v6/beacon-chain/p2p/testing"
 	"github.com/OffchainLabs/prysm/v6/cmd/beacon-chain/flags"
 	"github.com/OffchainLabs/prysm/v6/config/params"
 	ecdsaprysm "github.com/OffchainLabs/prysm/v6/crypto/ecdsa"
+	"github.com/OffchainLabs/prysm/v6/encoding/bytesutil"
 	"github.com/OffchainLabs/prysm/v6/testing/assert"
 	"github.com/OffchainLabs/prysm/v6/testing/require"
 	"github.com/ethereum/go-ethereum/p2p/enode"
 	"github.com/ethereum/go-ethereum/p2p/enr"
 	"github.com/libp2p/go-libp2p/core/crypto"
+	"github.com/libp2p/go-libp2p/core/network"
 	"github.com/prysmaticlabs/go-bitfield"
 )
 
@@ -36,17 +40,8 @@ func TestStartDiscV5_FindAndDialPeersWithSubnet(t *testing.T) {
 	// find and connect to a node already subscribed to a specific subnet.
 	// In our case: The node i is subscribed to subnet i, with i = 1, 2, 3
 
-	// Define the genesis validators root, to ensure everybody is on the same network.
-	const (
-		genesisValidatorRootStr = "0xdeadbeefcafecafedeadbeefcafecafedeadbeefcafecafedeadbeefcafecafe"
-		subnetCount             = 3
-		minimumPeersPerSubnet   = 1
-	)
-
-	genesisValidatorsRoot, err := hex.DecodeString(genesisValidatorRootStr[2:])
-	require.NoError(t, err)
-
-	// Create a context.
+	const subnetCount = 3
+	const minimumPeersPerSubnet = 1
 	ctx := t.Context()
 
 	// Use shorter period for testing.
@@ -58,6 +53,7 @@ func TestStartDiscV5_FindAndDialPeersWithSubnet(t *testing.T) {
 
 	// Create flags.
 	params.SetupTestConfigCleanup(t)
+	params.BeaconConfig().InitializeForkSchedule()
 	gFlags := new(flags.GlobalFlags)
 	gFlags.MinimumPeersPerSubnet = 1
 	flags.Init(gFlags)
@@ -74,7 +70,7 @@ func TestStartDiscV5_FindAndDialPeersWithSubnet(t *testing.T) {
 	bootNodeService := &Service{
 		cfg:                   &Config{UDPPort: 2000, TCPPort: 3000, QUICPort: 3000, DisableLivenessCheck: true, PingInterval: testPingInterval},
 		genesisTime:           genesisTime,
-		genesisValidatorsRoot: genesisValidatorsRoot,
+		genesisValidatorsRoot: params.BeaconConfig().GenesisValidatorsRoot[:],
 		custodyInfo:           &custodyInfo{},
 	}
 
@@ -111,7 +107,7 @@ func TestStartDiscV5_FindAndDialPeersWithSubnet(t *testing.T) {
 		require.NoError(t, err)
 
 		service.genesisTime = genesisTime
-		service.genesisValidatorsRoot = genesisValidatorsRoot
+		service.genesisValidatorsRoot = params.BeaconConfig().GenesisValidatorsRoot[:]
 		service.custodyInfo = &custodyInfo{}
 
 		nodeForkDigest, err := service.currentForkDigest()
@@ -158,11 +154,11 @@ func TestStartDiscV5_FindAndDialPeersWithSubnet(t *testing.T) {
 		DB:                   db,
 	}
 
-	service, err := NewService(ctx, cfg)
+	service, err := NewService(t.Context(), cfg)
 	require.NoError(t, err)
 
 	service.genesisTime = genesisTime
-	service.genesisValidatorsRoot = genesisValidatorsRoot
+	service.genesisValidatorsRoot = params.BeaconConfig().GenesisValidatorsRoot[:]
 	service.custodyInfo = &custodyInfo{}
 
 	service.Start()
@@ -550,3 +546,552 @@ func TestInitializePersistentSubnets(t *testing.T) {
 	assert.Equal(t, 2, len(subs))
 	assert.Equal(t, true, expTime.After(time.Now()))
 }
+
+func TestFindPeersWithSubnets_NodeDeduplication(t *testing.T) {
+	params.SetupTestConfigCleanup(t)
+	cache.SubnetIDs.EmptyAllCaches()
+	defer cache.SubnetIDs.EmptyAllCaches()
+
+	ctx := context.Background()
+	db := testDB.SetupDB(t)
+
+	localNode1 := createTestNodeWithID(t, "node1")
+	localNode2 := createTestNodeWithID(t, "node2")
+	localNode3 := createTestNodeWithID(t, "node3")
+
+	// Create different sequence versions of node1 with subnet 1
+	setNodeSubnets(localNode1, []uint64{1})
+	setNodeSeq(localNode1, 1)
+	node1_seq1_subnet1 := localNode1.Node()
+	setNodeSeq(localNode1, 2)
+	node1_seq2_subnet1 := localNode1.Node() // Same ID, higher seq
+	setNodeSeq(localNode1, 3)
+	node1_seq3_subnet1 := localNode1.Node() // Same ID, even higher seq
+
+	// Node2 with different sequences and subnets
+	setNodeSubnets(localNode2, []uint64{1})
+	node2_seq1_subnet1 := localNode2.Node()
+	setNodeSubnets(localNode2, []uint64{2}) // Different subnet
+	setNodeSeq(localNode2, 2)
+	node2_seq2_subnet2 := localNode2.Node()
+
+	// Node3 with multiple subnets
+	setNodeSubnets(localNode3, []uint64{1, 2})
+	node3_seq1_subnet1_2 := localNode3.Node()
+
+	tests := []struct {
+		name             string
+		nodes            []*enode.Node
+		defectiveSubnets map[uint64]int
+		expectedCount    int
+		description      string
+		eval             func(t *testing.T, result []*enode.Node) // Custom validation function
+	}{
+		{
+			name: "No duplicates - unique nodes with same subnet",
+			nodes: []*enode.Node{
+				node2_seq1_subnet1,
+				node3_seq1_subnet1_2,
+			},
+			defectiveSubnets: map[uint64]int{1: 2},
+			expectedCount:    2,
+			description:      "Should return all unique nodes subscribed to subnet",
+			eval:             nil, // No special validation needed
+		},
+		{
+			name: "Duplicate with lower seq first - should replace",
+			nodes: []*enode.Node{
+				node1_seq1_subnet1,
+				node1_seq2_subnet1, // Higher seq, should replace
+				node2_seq1_subnet1, // Different node to ensure we process enough nodes
+			},
+			defectiveSubnets: map[uint64]int{1: 2}, // Need 2 peers for subnet 1
+			expectedCount:    2,
+			description:      "Should replace with higher seq node for same subnet",
+			eval: func(t *testing.T, result []*enode.Node) {
+				found := false
+				for _, node := range result {
+					if node.ID() == node1_seq2_subnet1.ID() && node.Seq() == node1_seq2_subnet1.Seq() {
+						found = true
+						break
+					}
+				}
+				require.Equal(t, true, found, "Should have node with higher seq")
+			},
+		},
+		{
+			name: "Duplicate with higher seq first - should keep existing",
+			nodes: []*enode.Node{
+				node1_seq3_subnet1, // Higher seq
+				node1_seq2_subnet1, // Lower seq, should be skipped (continue branch)
+				node1_seq1_subnet1, // Even lower seq, should also be skipped (continue branch)
+				node2_seq1_subnet1, // Different node
+			},
+			defectiveSubnets: map[uint64]int{1: 2},
+			expectedCount:    2,
+			description:      "Should keep existing node with higher seq and skip lower seq duplicates",
+			eval: func(t *testing.T, result []*enode.Node) {
+				found := false
+				for _, node := range result {
+					if node.ID() == node1_seq3_subnet1.ID() && node.Seq() == node1_seq3_subnet1.Seq() {
+						found = true
+						break
+					}
+				}
+				require.Equal(t, true, found, "Should have node with highest seq")
+			},
+		},
+		{
+			name: "Multiple updates for same node",
+			nodes: []*enode.Node{
+				node1_seq1_subnet1,
+				node1_seq2_subnet1, // Should replace seq1
+				node1_seq3_subnet1, // Should replace seq2
+				node2_seq1_subnet1, // Different node
+			},
+			defectiveSubnets: map[uint64]int{1: 2},
+			expectedCount:    2,
+			description:      "Should keep updating to highest seq",
+			eval: func(t *testing.T, result []*enode.Node) {
+				found := false
+				for _, node := range result {
+					if node.ID() == node1_seq3_subnet1.ID() && node.Seq() == node1_seq3_subnet1.Seq() {
+						found = true
+						break
+					}
+				}
+				require.Equal(t, true, found, "Should have node with highest seq")
+			},
+		},
+		{
+			name: "Duplicate with equal seq in subnets - should skip",
+			nodes: []*enode.Node{
+				node1_seq2_subnet1, // First occurrence
+				node1_seq2_subnet1, // Same exact node instance, should be skipped (continue branch)
+				node2_seq1_subnet1, // Different node
+			},
+			defectiveSubnets: map[uint64]int{1: 2},
+			expectedCount:    2,
+			description:      "Should skip duplicate with equal sequence number in subnet search",
+			eval: func(t *testing.T, result []*enode.Node) {
+				foundNode1 := false
+				foundNode2 := false
+				node1Count := 0
+				for _, node := range result {
+					if node.ID() == node1_seq2_subnet1.ID() {
+						require.Equal(t, node1_seq2_subnet1.Seq(), node.Seq(), "Node1 should have expected seq")
+						foundNode1 = true
+						node1Count++
+					}
+					if node.ID() == node2_seq1_subnet1.ID() {
+						foundNode2 = true
+					}
+				}
+				require.Equal(t, true, foundNode1, "Should have node1")
+				require.Equal(t, true, foundNode2, "Should have node2")
+				require.Equal(t, 1, node1Count, "Should have exactly one instance of node1")
+			},
+		},
+		{
+			name: "Mix with different subnets",
+			nodes: []*enode.Node{
+				node2_seq1_subnet1,
+				node2_seq2_subnet2, // Higher seq but different subnet
+				node3_seq1_subnet1_2,
+			},
+			defectiveSubnets: map[uint64]int{1: 2, 2: 1},
+			expectedCount:    2, // node2 (latest) and node3
+			description:      "Should handle nodes with different subnet subscriptions",
+			eval:             nil, // Basic count validation is sufficient
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			gFlags := new(flags.GlobalFlags)
+			gFlags.MinimumPeersPerSubnet = 1
+			flags.Init(gFlags)
+			defer flags.Init(new(flags.GlobalFlags))
+
+			fakePeer := testp2p.NewTestP2P(t)
+
+			s := &Service{
+				cfg: &Config{
+					MaxPeers: 30,
+					DB:       db,
+				},
+				genesisTime:           time.Now(),
+				genesisValidatorsRoot: bytesutil.PadTo([]byte{'A'}, 32),
+				peers: peers.NewStatus(ctx, &peers.StatusConfig{
+					PeerLimit:    30,
+					ScorerParams: &scorers.Config{},
+				}),
+				host: fakePeer.BHost,
+			}
+
+			localNode := createTestNodeRandom(t)
+
+			mockIter := testp2p.NewMockIterator(tt.nodes)
+			s.dv5Listener = testp2p.NewMockListener(localNode, mockIter)
+
+			digest, err := s.currentForkDigest()
+			require.NoError(t, err)
+
+			ctxWithTimeout, cancel := context.WithTimeout(ctx, 100*time.Millisecond)
+			defer cancel()
+
+			result, err := s.findPeersWithSubnets(
+				ctxWithTimeout,
+				AttestationSubnetTopicFormat,
+				digest,
+				1,
+				tt.defectiveSubnets,
+			)
+
+			require.NoError(t, err, tt.description)
+			require.Equal(t, tt.expectedCount, len(result), tt.description)
+
+			if tt.eval != nil {
+				tt.eval(t, result)
+			}
+		})
+	}
+}
+
+func TestFindPeersWithSubnets_FilterPeerRemoval(t *testing.T) {
+	params.SetupTestConfigCleanup(t)
+	cache.SubnetIDs.EmptyAllCaches()
+	defer cache.SubnetIDs.EmptyAllCaches()
+
+	ctx := context.Background()
+	db := testDB.SetupDB(t)
+
+	localNode1 := createTestNodeWithID(t, "node1")
+	localNode2 := createTestNodeWithID(t, "node2")
+	localNode3 := createTestNodeWithID(t, "node3")
+
+	// Create versions of node1 with subnet 1
+	setNodeSubnets(localNode1, []uint64{1})
+	setNodeSeq(localNode1, 1)
+	node1_seq1_valid_subnet1 := localNode1.Node()
+
+	// Create bad version (higher seq)
+	setNodeSeq(localNode1, 2)
+	node1_seq2_bad_subnet1 := localNode1.Node()
+
+	// Create another valid version
+	setNodeSeq(localNode1, 3)
+	node1_seq3_valid_subnet1 := localNode1.Node()
+
+	// Node2 with subnet 1
+	setNodeSubnets(localNode2, []uint64{1})
+	node2_seq1_valid_subnet1 := localNode2.Node()
+
+	// Node3 with subnet 1 and 2
+	setNodeSubnets(localNode3, []uint64{1, 2})
+	node3_seq1_valid_subnet1_2 := localNode3.Node()
+
+	tests := []struct {
+		name             string
+		nodes            []*enode.Node
+		defectiveSubnets map[uint64]int
+		expectedCount    int
+		description      string
+		eval             func(t *testing.T, result []*enode.Node)
+	}{
+		{
+			name: "Valid node in subnet followed by bad version - should remove",
+			nodes: []*enode.Node{
+				node1_seq1_valid_subnet1, // First add valid node with subnet 1
+				node1_seq2_bad_subnet1,   // Invalid version with higher seq - should delete
+				node2_seq1_valid_subnet1, // Different valid node with subnet 1
+			},
+			defectiveSubnets: map[uint64]int{1: 2}, // Need 2 peers for subnet 1
+			expectedCount:    1,                    // Only node2 should remain
+			description:      "Should remove node from map when bad version arrives, even if it has required subnet",
+			eval: func(t *testing.T, result []*enode.Node) {
+				foundNode1 := false
+				foundNode2 := false
+				for _, node := range result {
+					if node.ID() == node1_seq1_valid_subnet1.ID() {
+						foundNode1 = true
+					}
+					if node.ID() == node2_seq1_valid_subnet1.ID() {
+						foundNode2 = true
+					}
+				}
+				require.Equal(t, false, foundNode1, "Node1 should have been removed despite having subnet")
+				require.Equal(t, true, foundNode2, "Node2 should be present")
+			},
+		},
+		{
+			name: "Bad node with subnet stays bad even with higher seq",
+			nodes: []*enode.Node{
+				node1_seq2_bad_subnet1,   // First bad node - not added
+				node1_seq3_valid_subnet1, // Higher seq but same bad peer ID
+				node2_seq1_valid_subnet1, // Different valid node
+			},
+			defectiveSubnets: map[uint64]int{1: 2},
+			expectedCount:    1, // Only node2 (node1 remains bad)
+			description:      "Bad peer with subnet remains bad even with higher seq",
+			eval: func(t *testing.T, result []*enode.Node) {
+				foundNode1 := false
+				foundNode2 := false
+				for _, node := range result {
+					if node.ID() == node1_seq3_valid_subnet1.ID() {
+						foundNode1 = true
+					}
+					if node.ID() == node2_seq1_valid_subnet1.ID() {
+						foundNode2 = true
+					}
+				}
+				require.Equal(t, false, foundNode1, "Node1 should remain bad despite having subnet")
+				require.Equal(t, true, foundNode2, "Node2 should be present")
+			},
+		},
+		{
+			name: "Mixed valid and bad nodes with subnets",
+			nodes: []*enode.Node{
+				node1_seq1_valid_subnet1,   // Add valid node1 with subnet
+				node2_seq1_valid_subnet1,   // Add valid node2 with subnet
+				node1_seq2_bad_subnet1,     // Invalid update for node1 - should remove
+				node3_seq1_valid_subnet1_2, // Add valid node3 with multiple subnets
+			},
+			defectiveSubnets: map[uint64]int{1: 3}, // Need 3 peers for subnet 1
+			expectedCount:    2,                    // Only node2 and node3 should remain
+			description:      "Should handle removal of nodes with subnets when they become bad",
+			eval: func(t *testing.T, result []*enode.Node) {
+				foundNode1 := false
+				foundNode2 := false
+				foundNode3 := false
+				for _, node := range result {
+					if node.ID() == node1_seq1_valid_subnet1.ID() {
+						foundNode1 = true
+					}
+					if node.ID() == node2_seq1_valid_subnet1.ID() {
+						foundNode2 = true
+					}
+					if node.ID() == node3_seq1_valid_subnet1_2.ID() {
+						foundNode3 = true
+					}
+				}
+				require.Equal(t, false, foundNode1, "Node1 should have been removed")
+				require.Equal(t, true, foundNode2, "Node2 should be present")
+				require.Equal(t, true, foundNode3, "Node3 should be present")
+			},
+		},
+		{
+			name: "Node with subnet marked bad stays bad for all sequences",
+			nodes: []*enode.Node{
+				node1_seq1_valid_subnet1, // Add valid node1 with subnet
+				node1_seq2_bad_subnet1,   // Bad update - should remove and mark bad
+				node1_seq3_valid_subnet1, // Higher seq but still same bad peer ID
+				node2_seq1_valid_subnet1, // Different valid node
+			},
+			defectiveSubnets: map[uint64]int{1: 2},
+			expectedCount:    1, // Only node2 (node1 stays bad)
+			description:      "Once marked bad, subnet peer stays bad for all sequences",
+			eval: func(t *testing.T, result []*enode.Node) {
+				foundNode1 := false
+				foundNode2 := false
+				for _, node := range result {
+					if node.ID() == node1_seq3_valid_subnet1.ID() {
+						foundNode1 = true
+					}
+					if node.ID() == node2_seq1_valid_subnet1.ID() {
+						foundNode2 = true
+					}
+				}
+				require.Equal(t, false, foundNode1, "Node1 should stay bad")
+				require.Equal(t, true, foundNode2, "Node2 should be present")
+			},
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			// Initialize flags for subnet operations
+			gFlags := new(flags.GlobalFlags)
+			gFlags.MinimumPeersPerSubnet = 1
+			flags.Init(gFlags)
+			defer flags.Init(new(flags.GlobalFlags))
+
+			// Create test P2P instance
+			fakePeer := testp2p.NewTestP2P(t)
+
+			// Create mock service
+			s := &Service{
+				cfg: &Config{
+					MaxPeers: 30,
+					DB:       db,
+				},
+				genesisTime:           time.Now(),
+				genesisValidatorsRoot: bytesutil.PadTo([]byte{'A'}, 32),
+				peers: peers.NewStatus(ctx, &peers.StatusConfig{
+					PeerLimit:    30,
+					ScorerParams: &scorers.Config{},
+				}),
+				host: fakePeer.BHost,
+			}
+
+			// Mark specific node versions as "bad" to simulate filterPeer failures
+			for _, node := range tt.nodes {
+				if node == node1_seq2_bad_subnet1 {
+					// Get peer ID from the node to mark it as bad
+					peerData, _, _ := convertToAddrInfo(node)
+					if peerData != nil {
+						s.peers.Add(node.Record(), peerData.ID, nil, network.DirUnknown)
+						// Mark as bad peer - this will make filterPeer return false
+						s.peers.Scorers().BadResponsesScorer().Increment(peerData.ID)
+						s.peers.Scorers().BadResponsesScorer().Increment(peerData.ID)
+						s.peers.Scorers().BadResponsesScorer().Increment(peerData.ID)
+					}
+				}
+			}
+
+			localNode := createTestNodeRandom(t)
+
+			mockIter := testp2p.NewMockIterator(tt.nodes)
+			s.dv5Listener = testp2p.NewMockListener(localNode, mockIter)
+
+			digest, err := s.currentForkDigest()
+			require.NoError(t, err)
+
+			ctxWithTimeout, cancel := context.WithTimeout(ctx, 100*time.Millisecond)
+			defer cancel()
+
+			result, err := s.findPeersWithSubnets(
+				ctxWithTimeout,
+				AttestationSubnetTopicFormat,
+				digest,
+				1,
+				tt.defectiveSubnets,
+			)
+
+			require.NoError(t, err, tt.description)
+			require.Equal(t, tt.expectedCount, len(result), tt.description)
+
+			if tt.eval != nil {
+				tt.eval(t, result)
+			}
+		})
+	}
+}
+
+// callbackIterator allows us to execute callbacks at specific points during iteration
+type callbackIteratorForSubnets struct {
+	nodes     []*enode.Node
+	index     int
+	callbacks map[int]func() // map from index to callback function
+}
+
+func (c *callbackIteratorForSubnets) Next() bool {
+	// Execute callback before checking if we can continue (if one exists)
+	if callback, exists := c.callbacks[c.index]; exists {
+		callback()
+	}
+
+	return c.index < len(c.nodes)
+}
+
+func (c *callbackIteratorForSubnets) Node() *enode.Node {
+	if c.index >= len(c.nodes) {
+		return nil
+	}
+
+	node := c.nodes[c.index]
+	c.index++
+	return node
+}
+
+func (c *callbackIteratorForSubnets) Close() {
+	// Nothing to clean up for this simple implementation
+}
+
+func TestFindPeersWithSubnets_received_bad_existing_node(t *testing.T) {
+	// This test successfully triggers delete(nodeByNodeID, node.ID()) in subnets.go by:
+	// 1. Processing node1_seq1 first (passes filterPeer, gets added to map
+	// 2. Callback marks peer as bad before processing node1_seq2"
+	// 3. Processing node1_seq2 (fails filterPeer, triggers delete since ok=true
+	params.SetupTestConfigCleanup(t)
+	cache.SubnetIDs.EmptyAllCaches()
+	defer cache.SubnetIDs.EmptyAllCaches()
+
+	ctx := context.Background()
+	db := testDB.SetupDB(t)
+
+	// Create LocalNode with same ID but different sequences
+	localNode1 := createTestNodeWithID(t, "testnode")
+	setNodeSubnets(localNode1, []uint64{1})
+	node1_seq1 := localNode1.Node() // Get current node
+	currentSeq := node1_seq1.Seq()
+	setNodeSeq(localNode1, currentSeq+1) // Increment sequence by 1
+	node1_seq2 := localNode1.Node()      // This should have higher seq
+
+	// Additional node to ensure we have enough peers to process
+	localNode2 := createTestNodeWithID(t, "othernode")
+	setNodeSubnets(localNode2, []uint64{1})
+	node2 := localNode2.Node()
+
+	gFlags := new(flags.GlobalFlags)
+	gFlags.MinimumPeersPerSubnet = 1
+	flags.Init(gFlags)
+	defer flags.Init(new(flags.GlobalFlags))
+
+	fakePeer := testp2p.NewTestP2P(t)
+
+	service := &Service{
+		cfg: &Config{
+			MaxPeers: 30,
+			DB:       db,
+		},
+		genesisTime:           time.Now(),
+		genesisValidatorsRoot: bytesutil.PadTo([]byte{'A'}, 32),
+		peers: peers.NewStatus(ctx, &peers.StatusConfig{
+			PeerLimit:    30,
+			ScorerParams: &scorers.Config{},
+		}),
+		host: fakePeer.BHost,
+	}
+
+	// Create iterator with callback that marks peer as bad before processing node1_seq2
+	iter := &callbackIteratorForSubnets{
+		nodes: []*enode.Node{node1_seq1, node1_seq2, node2},
+		index: 0,
+		callbacks: map[int]func(){
+			1: func() { // Before processing node1_seq2 (index 1)
+				// Mark peer as bad before processing node1_seq2
+				peerData, _, _ := convertToAddrInfo(node1_seq2)
+				if peerData != nil {
+					service.peers.Add(node1_seq2.Record(), peerData.ID, nil, network.DirUnknown)
+					// Mark as bad peer - need enough increments to exceed threshold (6)
+					for i := 0; i < 10; i++ {
+						service.peers.Scorers().BadResponsesScorer().Increment(peerData.ID)
+					}
+				}
+			},
+		},
+	}
+
+	localNode := createTestNodeRandom(t)
+	service.dv5Listener = testp2p.NewMockListener(localNode, iter)
+
+	digest, err := service.currentForkDigest()
+	require.NoError(t, err)
+
+	// Run findPeersWithSubnets - node1_seq1 gets processed first, then callback marks peer bad, then node1_seq2 fails
+	ctxWithTimeout, cancel := context.WithTimeout(ctx, 1*time.Second)
+	defer cancel()
+
+	result, err := service.findPeersWithSubnets(
+		ctxWithTimeout,
+		AttestationSubnetTopicFormat,
+		digest,
+		1,
+		map[uint64]int{1: 2}, // Need 2 peers for subnet 1
+	)
+
+	require.NoError(t, err)
+	require.Equal(t, 1, len(result))
+	require.Equal(t, localNode2.Node().ID(), result[0].ID()) // only node2 should remain
+}

beacon-chain/p2p/testing/BUILD.bazel

@@ -7,6 +7,7 @@ go_library(
         "fuzz_p2p.go",
         "mock_broadcaster.go",
         "mock_host.go",
+        "mock_listener.go",
         "mock_metadataprovider.go",
         "mock_peermanager.go",
         "mock_peersprovider.go",

beacon-chain/p2p/testing/fuzz_p2p.go

@@ -167,8 +167,8 @@ func (*FakeP2P) BroadcastLightClientFinalityUpdate(_ context.Context, _ interfac
 	return nil
 }
 
-// BroadcastDataColumn -- fake.
-func (*FakeP2P) BroadcastDataColumn(_ [fieldparams.RootLength]byte, _ uint64, _ *ethpb.DataColumnSidecar) error {
+// BroadcastDataColumnSidecar -- fake.
+func (*FakeP2P) BroadcastDataColumnSidecar(_ [fieldparams.RootLength]byte, _ uint64, _ *ethpb.DataColumnSidecar) error {
 	return nil
 }
 

beacon-chain/p2p/testing/mock_broadcaster.go

@@ -62,8 +62,8 @@ func (m *MockBroadcaster) BroadcastLightClientFinalityUpdate(_ context.Context,
 	return nil
 }
 
-// BroadcastDataColumn broadcasts a data column for mock.
-func (m *MockBroadcaster) BroadcastDataColumn([fieldparams.RootLength]byte, uint64, *ethpb.DataColumnSidecar) error {
+// BroadcastDataColumnSidecar broadcasts a data column for mock.
+func (m *MockBroadcaster) BroadcastDataColumnSidecar([fieldparams.RootLength]byte, uint64, *ethpb.DataColumnSidecar) error {
 	m.BroadcastCalled.Store(true)
 	return nil
 }

beacon-chain/p2p/testing/mock_listener.go

@@ -0,0 +1,128 @@
+package testing
+
+import (
+	"github.com/ethereum/go-ethereum/p2p/enode"
+)
+
+// MockListener is a mock implementation of the Listener and ListenerRebooter interfaces
+// that can be used in tests. It provides configurable behavior for all methods.
+type MockListener struct {
+	LocalNodeFunc   func() *enode.LocalNode
+	SelfFunc        func() *enode.Node
+	RandomNodesFunc func() enode.Iterator
+	LookupFunc      func(enode.ID) []*enode.Node
+	ResolveFunc     func(*enode.Node) *enode.Node
+	PingFunc        func(*enode.Node) error
+	RequestENRFunc  func(*enode.Node) (*enode.Node, error)
+	RebootFunc      func() error
+	CloseFunc       func()
+
+	// Default implementations
+	localNode *enode.LocalNode
+	iterator  enode.Iterator
+}
+
+// NewMockListener creates a new MockListener with default implementations
+func NewMockListener(localNode *enode.LocalNode, iterator enode.Iterator) *MockListener {
+	return &MockListener{
+		localNode: localNode,
+		iterator:  iterator,
+	}
+}
+
+func (m *MockListener) LocalNode() *enode.LocalNode {
+	if m.LocalNodeFunc != nil {
+		return m.LocalNodeFunc()
+	}
+	return m.localNode
+}
+
+func (m *MockListener) Self() *enode.Node {
+	if m.SelfFunc != nil {
+		return m.SelfFunc()
+	}
+	if m.localNode != nil {
+		return m.localNode.Node()
+	}
+	return nil
+}
+
+func (m *MockListener) RandomNodes() enode.Iterator {
+	if m.RandomNodesFunc != nil {
+		return m.RandomNodesFunc()
+	}
+	return m.iterator
+}
+
+func (m *MockListener) Lookup(id enode.ID) []*enode.Node {
+	if m.LookupFunc != nil {
+		return m.LookupFunc(id)
+	}
+	return nil
+}
+
+func (m *MockListener) Resolve(node *enode.Node) *enode.Node {
+	if m.ResolveFunc != nil {
+		return m.ResolveFunc(node)
+	}
+	return nil
+}
+
+func (m *MockListener) Ping(node *enode.Node) error {
+	if m.PingFunc != nil {
+		return m.PingFunc(node)
+	}
+	return nil
+}
+
+func (m *MockListener) RequestENR(node *enode.Node) (*enode.Node, error) {
+	if m.RequestENRFunc != nil {
+		return m.RequestENRFunc(node)
+	}
+	return nil, nil
+}
+
+func (m *MockListener) RebootListener() error {
+	if m.RebootFunc != nil {
+		return m.RebootFunc()
+	}
+	return nil
+}
+
+func (m *MockListener) Close() {
+	if m.CloseFunc != nil {
+		m.CloseFunc()
+	}
+}
+
+// MockIterator is a mock implementation of enode.Iterator for testing
+type MockIterator struct {
+	Nodes    []*enode.Node
+	Position int
+	Closed   bool
+}
+
+func NewMockIterator(nodes []*enode.Node) *MockIterator {
+	return &MockIterator{
+		Nodes: nodes,
+	}
+}
+
+func (m *MockIterator) Next() bool {
+	if m.Closed || m.Position >= len(m.Nodes) {
+		return false
+	}
+	m.Position++
+	return true
+}
+
+func (m *MockIterator) Node() *enode.Node {
+	if m.Position == 0 || m.Position > len(m.Nodes) {
+		return nil
+	}
+	return m.Nodes[m.Position-1]
+}
+
+func (m *MockIterator) Close() {
+	m.Closed = true
+}

beacon-chain/p2p/testing/p2p.go

@@ -228,8 +228,8 @@ func (p *TestP2P) BroadcastLightClientFinalityUpdate(_ context.Context, _ interf
 	return nil
 }
 
-// BroadcastDataColumn broadcasts a data column for mock.
-func (p *TestP2P) BroadcastDataColumn([fieldparams.RootLength]byte, uint64, *ethpb.DataColumnSidecar) error {
+// BroadcastDataColumnSidecar broadcasts a data column for mock.
+func (p *TestP2P) BroadcastDataColumnSidecar([fieldparams.RootLength]byte, uint64, *ethpb.DataColumnSidecar) error {
 	p.BroadcastCalled.Store(true)
 	return nil
 }

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

@@ -72,6 +72,7 @@ go_library(
 go_test(
     name = "go_default_test",
     srcs = [
+        "handlers_equivocation_test.go",
         "handlers_pool_test.go",
         "handlers_state_test.go",
         "handlers_test.go",

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

@@ -701,7 +701,7 @@ func (s *Server) publishBlockSSZ(ctx context.Context, w http.ResponseWriter, r *
 	// Validate and optionally broadcast sidecars on equivocation.
 	if err := s.validateBroadcast(ctx, r, genericBlock); err != nil {
 		if errors.Is(err, errEquivocatedBlock) {
-			b, err := blocks.NewSignedBeaconBlock(genericBlock)
+			b, err := blocks.NewSignedBeaconBlock(genericBlock.Block)
 			if err != nil {
 				httputil.HandleError(w, err.Error(), http.StatusBadRequest)
 				return
@@ -855,7 +855,7 @@ func (s *Server) publishBlock(ctx context.Context, w http.ResponseWriter, r *htt
 	// Validate and optionally broadcast sidecars on equivocation.
 	if err := s.validateBroadcast(ctx, r, genericBlock); err != nil {
 		if errors.Is(err, errEquivocatedBlock) {
-			b, err := blocks.NewSignedBeaconBlock(genericBlock)
+			b, err := blocks.NewSignedBeaconBlock(genericBlock.Block)
 			if err != nil {
 				httputil.HandleError(w, err.Error(), http.StatusBadRequest)
 				return
@@ -1078,6 +1078,10 @@ func (s *Server) validateBlobSidecars(blk interfaces.SignedBeaconBlock, blobs []
 	if len(blobs) != len(proofs) || len(blobs) != len(kzgs) {
 		return errors.New("number of blobs, proofs, and commitments do not match")
 	}
+	maxBlobsPerBlock := params.BeaconConfig().MaxBlobsPerBlock(blk.Block().Slot())
+	if len(blobs) > maxBlobsPerBlock {
+		return fmt.Errorf("number of blobs over max, %d > %d", len(blobs), maxBlobsPerBlock)
+	}
 	for i, blob := range blobs {
 		b := kzg4844.Blob(blob)
 		if err := kzg4844.VerifyBlobProof(&b, kzg4844.Commitment(kzgs[i]), kzg4844.Proof(proofs[i])); err != nil {
@@ -1220,7 +1224,7 @@ func (s *Server) GetStateFork(w http.ResponseWriter, r *http.Request) {
 	fork := st.Fork()
 	isOptimistic, err := helpers.IsOptimistic(ctx, []byte(stateId), s.OptimisticModeFetcher, s.Stater, s.ChainInfoFetcher, s.BeaconDB)
 	if err != nil {
-		httputil.HandleError(w, "Could not check optimistic status"+err.Error(), http.StatusInternalServerError)
+		helpers.HandleIsOptimisticError(w, err)
 		return
 	}
 	blockRoot, err := st.LatestBlockHeader().HashTreeRoot()
@@ -1331,7 +1335,7 @@ func (s *Server) GetCommittees(w http.ResponseWriter, r *http.Request) {
 
 	isOptimistic, err := helpers.IsOptimistic(ctx, []byte(stateId), s.OptimisticModeFetcher, s.Stater, s.ChainInfoFetcher, s.BeaconDB)
 	if err != nil {
-		httputil.HandleError(w, "Could not check optimistic status: "+err.Error(), http.StatusInternalServerError)
+		helpers.HandleIsOptimisticError(w, err)
 		return
 	}
 
@@ -1512,7 +1516,7 @@ func (s *Server) GetFinalityCheckpoints(w http.ResponseWriter, r *http.Request)
 	}
 	isOptimistic, err := helpers.IsOptimistic(ctx, []byte(stateId), s.OptimisticModeFetcher, s.Stater, s.ChainInfoFetcher, s.BeaconDB)
 	if err != nil {
-		httputil.HandleError(w, "Could not check optimistic status: "+err.Error(), http.StatusInternalServerError)
+		helpers.HandleIsOptimisticError(w, err)
 		return
 	}
 	blockRoot, err := st.LatestBlockHeader().HashTreeRoot()
@@ -1686,7 +1690,7 @@ func (s *Server) GetPendingConsolidations(w http.ResponseWriter, r *http.Request
 	} else {
 		isOptimistic, err := helpers.IsOptimistic(ctx, []byte(stateId), s.OptimisticModeFetcher, s.Stater, s.ChainInfoFetcher, s.BeaconDB)
 		if err != nil {
-			httputil.HandleError(w, "Could not check optimistic status: "+err.Error(), http.StatusInternalServerError)
+			helpers.HandleIsOptimisticError(w, err)
 			return
 		}
 		blockRoot, err := st.LatestBlockHeader().HashTreeRoot()
@@ -1742,7 +1746,7 @@ func (s *Server) GetPendingDeposits(w http.ResponseWriter, r *http.Request) {
 	} else {
 		isOptimistic, err := helpers.IsOptimistic(ctx, []byte(stateId), s.OptimisticModeFetcher, s.Stater, s.ChainInfoFetcher, s.BeaconDB)
 		if err != nil {
-			httputil.HandleError(w, "Could not check optimistic status: "+err.Error(), http.StatusInternalServerError)
+			helpers.HandleIsOptimisticError(w, err)
 			return
 		}
 		blockRoot, err := st.LatestBlockHeader().HashTreeRoot()
@@ -1798,7 +1802,7 @@ func (s *Server) GetPendingPartialWithdrawals(w http.ResponseWriter, r *http.Req
 	} else {
 		isOptimistic, err := helpers.IsOptimistic(ctx, []byte(stateId), s.OptimisticModeFetcher, s.Stater, s.ChainInfoFetcher, s.BeaconDB)
 		if err != nil {
-			httputil.HandleError(w, "Could not check optimistic status: "+err.Error(), http.StatusInternalServerError)
+			helpers.HandleIsOptimisticError(w, err)
 			return
 		}
 		blockRoot, err := st.LatestBlockHeader().HashTreeRoot()
@@ -1851,7 +1855,7 @@ func (s *Server) GetProposerLookahead(w http.ResponseWriter, r *http.Request) {
 	} else {
 		isOptimistic, err := helpers.IsOptimistic(ctx, []byte(stateId), s.OptimisticModeFetcher, s.Stater, s.ChainInfoFetcher, s.BeaconDB)
 		if err != nil {
-			httputil.HandleError(w, "Could not check optimistic status: "+err.Error(), http.StatusInternalServerError)
+			helpers.HandleIsOptimisticError(w, err)
 			return
 		}
 		blockRoot, err := st.LatestBlockHeader().HashTreeRoot()

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

@@ -0,0 +1,35 @@
+package beacon
+
+import (
+	"encoding/json"
+	"testing"
+
+	"github.com/OffchainLabs/prysm/v6/api/server/structs"
+	rpctesting "github.com/OffchainLabs/prysm/v6/beacon-chain/rpc/eth/shared/testing"
+	"github.com/OffchainLabs/prysm/v6/consensus-types/blocks"
+	"github.com/OffchainLabs/prysm/v6/testing/require"
+)
+
+// TestBlocks_NewSignedBeaconBlock_EquivocationFix tests that blocks.NewSignedBeaconBlock
+// correctly handles the fixed case where genericBlock.Block is passed instead of genericBlock
+func TestBlocks_NewSignedBeaconBlock_EquivocationFix(t *testing.T) {
+	// Parse the Phase0 JSON block
+	var block structs.SignedBeaconBlock
+	err := json.Unmarshal([]byte(rpctesting.Phase0Block), &block)
+	require.NoError(t, err)
+	
+	// Convert to generic format
+	genericBlock, err := block.ToGeneric()
+	require.NoError(t, err)
+	
+	// Test the FIX: pass genericBlock.Block instead of genericBlock
+	// This is what our fix changed in handlers.go line 704 and 858
+	_, err = blocks.NewSignedBeaconBlock(genericBlock.Block)
+	require.NoError(t, err, "NewSignedBeaconBlock should work with genericBlock.Block")
+	
+	// Test the BROKEN version: pass genericBlock directly (this should fail)
+	_, err = blocks.NewSignedBeaconBlock(genericBlock)
+	if err == nil {
+		t.Errorf("NewSignedBeaconBlock should fail with whole genericBlock but succeeded")
+	}
+}

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

@@ -56,7 +56,7 @@ func (s *Server) GetStateRoot(w http.ResponseWriter, r *http.Request) {
 	}
 	isOptimistic, err := helpers.IsOptimistic(ctx, []byte(stateId), s.OptimisticModeFetcher, s.Stater, s.ChainInfoFetcher, s.BeaconDB)
 	if err != nil {
-		httputil.HandleError(w, "Could not check optimistic status: "+err.Error(), http.StatusInternalServerError)
+		helpers.HandleIsOptimisticError(w, err)
 		return
 	}
 	blockRoot, err := st.LatestBlockHeader().HashTreeRoot()
@@ -125,7 +125,7 @@ func (s *Server) GetRandao(w http.ResponseWriter, r *http.Request) {
 
 	isOptimistic, err := helpers.IsOptimistic(ctx, []byte(stateId), s.OptimisticModeFetcher, s.Stater, s.ChainInfoFetcher, s.BeaconDB)
 	if err != nil {
-		httputil.HandleError(w, "Could not check optimistic status: "+err.Error(), http.StatusInternalServerError)
+		helpers.HandleIsOptimisticError(w, err)
 		return
 	}
 
@@ -227,7 +227,7 @@ func (s *Server) GetSyncCommittees(w http.ResponseWriter, r *http.Request) {
 
 	isOptimistic, err := helpers.IsOptimistic(ctx, []byte(stateId), s.OptimisticModeFetcher, s.Stater, s.ChainInfoFetcher, s.BeaconDB)
 	if err != nil {
-		httputil.HandleError(w, "Could not check optimistic status: "+err.Error(), http.StatusInternalServerError)
+		helpers.HandleIsOptimisticError(w, err)
 		return
 	}
 

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

@@ -4800,6 +4800,222 @@ func Test_validateBlobSidecars(t *testing.T) {
 	b, err = blocks.NewSignedBeaconBlock(blk)
 	require.NoError(t, err)
 	require.ErrorContains(t, "could not verify blob proof: can't verify opening proof", s.validateBlobSidecars(b, [][]byte{blob[:]}, [][]byte{proof[:]}))
+
+	blobs := [][]byte{}
+	commitments := [][]byte{}
+	proofs := [][]byte{}
+	for i := 0; i < 10; i++ {
+		blobs = append(blobs, blob[:])
+		commitments = append(commitments, commitment[:])
+		proofs = append(proofs, proof[:])
+	}
+	t.Run("pre-Deneb block should return early", func(t *testing.T) {
+		// Create a pre-Deneb block (e.g., Capella)
+		blk := util.NewBeaconBlockCapella()
+		b, err := blocks.NewSignedBeaconBlock(blk)
+		require.NoError(t, err)
+		s := &Server{}
+		// Should return nil for pre-Deneb blocks regardless of blobs
+		require.NoError(t, s.validateBlobSidecars(b, [][]byte{}, [][]byte{}))
+		require.NoError(t, s.validateBlobSidecars(b, blobs[:1], proofs[:1]))
+	})
+
+	t.Run("Deneb block with valid single blob", func(t *testing.T) {
+		blk := util.NewBeaconBlockDeneb()
+		blk.Block.Body.BlobKzgCommitments = [][]byte{commitment[:]}
+		b, err := blocks.NewSignedBeaconBlock(blk)
+		require.NoError(t, err)
+		s := &Server{}
+		require.NoError(t, s.validateBlobSidecars(b, [][]byte{blob[:]}, [][]byte{proof[:]}))
+	})
+
+	t.Run("Deneb block with max blobs (6)", func(t *testing.T) {
+		cfg := params.BeaconConfig().Copy()
+		defer params.OverrideBeaconConfig(cfg)
+
+		testCfg := params.BeaconConfig().Copy()
+		testCfg.DenebForkEpoch = 0
+		testCfg.ElectraForkEpoch = 100
+		testCfg.DeprecatedMaxBlobsPerBlock = 6
+		params.OverrideBeaconConfig(testCfg)
+
+		blk := util.NewBeaconBlockDeneb()
+		blk.Block.Slot = 10 // Deneb slot
+		blk.Block.Body.BlobKzgCommitments = commitments[:6]
+		b, err := blocks.NewSignedBeaconBlock(blk)
+		require.NoError(t, err)
+		s := &Server{}
+		// Should pass with exactly 6 blobs
+		require.NoError(t, s.validateBlobSidecars(b, blobs[:6], proofs[:6]))
+	})
+
+	t.Run("Deneb block exceeding max blobs", func(t *testing.T) {
+		cfg := params.BeaconConfig().Copy()
+		defer params.OverrideBeaconConfig(cfg)
+
+		testCfg := params.BeaconConfig().Copy()
+		testCfg.DenebForkEpoch = 0
+		testCfg.ElectraForkEpoch = 100
+		testCfg.DeprecatedMaxBlobsPerBlock = 6
+		params.OverrideBeaconConfig(testCfg)
+
+		blk := util.NewBeaconBlockDeneb()
+		blk.Block.Slot = 10 // Deneb slot
+		blk.Block.Body.BlobKzgCommitments = commitments[:7]
+		b, err := blocks.NewSignedBeaconBlock(blk)
+		require.NoError(t, err)
+		s := &Server{}
+		// Should fail with 7 blobs when max is 6
+		err = s.validateBlobSidecars(b, blobs[:7], proofs[:7])
+		require.ErrorContains(t, "number of blobs over max, 7 > 6", err)
+	})
+
+	t.Run("Electra block with valid blobs", func(t *testing.T) {
+		cfg := params.BeaconConfig().Copy()
+		defer params.OverrideBeaconConfig(cfg)
+
+		// Set up Electra config with max 9 blobs
+		testCfg := params.BeaconConfig().Copy()
+		testCfg.DenebForkEpoch = 0
+		testCfg.ElectraForkEpoch = 5
+		testCfg.DeprecatedMaxBlobsPerBlock = 6
+		testCfg.DeprecatedMaxBlobsPerBlockElectra = 9
+		params.OverrideBeaconConfig(testCfg)
+
+		blk := util.NewBeaconBlockElectra()
+		blk.Block.Slot = 160 // Electra slot (epoch 5+)
+		blk.Block.Body.BlobKzgCommitments = commitments[:9]
+		b, err := blocks.NewSignedBeaconBlock(blk)
+		require.NoError(t, err)
+		s := &Server{}
+		// Should pass with 9 blobs in Electra
+		require.NoError(t, s.validateBlobSidecars(b, blobs[:9], proofs[:9]))
+	})
+
+	t.Run("Electra block exceeding max blobs", func(t *testing.T) {
+		cfg := params.BeaconConfig().Copy()
+		defer params.OverrideBeaconConfig(cfg)
+
+		// Set up Electra config with max 9 blobs
+		testCfg := params.BeaconConfig().Copy()
+		testCfg.DenebForkEpoch = 0
+		testCfg.ElectraForkEpoch = 5
+		testCfg.DeprecatedMaxBlobsPerBlock = 6
+		testCfg.DeprecatedMaxBlobsPerBlockElectra = 9
+		params.OverrideBeaconConfig(testCfg)
+
+		blk := util.NewBeaconBlockElectra()
+		blk.Block.Slot = 160 // Electra slot
+		blk.Block.Body.BlobKzgCommitments = commitments[:10]
+		b, err := blocks.NewSignedBeaconBlock(blk)
+		require.NoError(t, err)
+		s := &Server{}
+		// Should fail with 10 blobs when max is 9
+		err = s.validateBlobSidecars(b, blobs[:10], proofs[:10])
+		require.ErrorContains(t, "number of blobs over max, 10 > 9", err)
+	})
+
+	t.Run("Fulu block with valid blobs", func(t *testing.T) {
+		cfg := params.BeaconConfig().Copy()
+		defer params.OverrideBeaconConfig(cfg)
+
+		testCfg := params.BeaconConfig().Copy()
+		testCfg.DenebForkEpoch = 0
+		testCfg.ElectraForkEpoch = 5
+		testCfg.FuluForkEpoch = 10
+		testCfg.DeprecatedMaxBlobsPerBlock = 6
+		testCfg.DeprecatedMaxBlobsPerBlockElectra = 9
+		params.OverrideBeaconConfig(testCfg)
+
+		blk := util.NewBeaconBlockFulu()
+		blk.Block.Slot = 320 // Fulu slot (epoch 10+)
+		blk.Block.Body.BlobKzgCommitments = commitments[:9]
+		b, err := blocks.NewSignedBeaconBlock(blk)
+		require.NoError(t, err)
+		s := &Server{}
+		// Should pass with 9 blobs in Fulu
+		require.NoError(t, s.validateBlobSidecars(b, blobs[:9], proofs[:9]))
+	})
+
+	t.Run("Fulu block exceeding max blobs", func(t *testing.T) {
+		cfg := params.BeaconConfig().Copy()
+		defer params.OverrideBeaconConfig(cfg)
+
+		testCfg := params.BeaconConfig().Copy()
+		testCfg.DenebForkEpoch = 0
+		testCfg.ElectraForkEpoch = 5
+		testCfg.FuluForkEpoch = 10
+		testCfg.DeprecatedMaxBlobsPerBlock = 6
+		testCfg.DeprecatedMaxBlobsPerBlockElectra = 9
+		params.OverrideBeaconConfig(testCfg)
+
+		blk := util.NewBeaconBlockFulu()
+		blk.Block.Slot = 320 // Fulu slot (epoch 10+)
+		blk.Block.Body.BlobKzgCommitments = commitments[:10]
+		b, err := blocks.NewSignedBeaconBlock(blk)
+		require.NoError(t, err)
+		s := &Server{}
+		// Should fail with 10 blobs when max is 9
+		err = s.validateBlobSidecars(b, blobs[:10], proofs[:10])
+		require.ErrorContains(t, "number of blobs over max, 10 > 9", err)
+	})
+
+	t.Run("BlobSchedule with progressive increases (BPO)", func(t *testing.T) {
+		cfg := params.BeaconConfig().Copy()
+		defer params.OverrideBeaconConfig(cfg)
+
+		// Set up config with BlobSchedule (BPO - Blob Production Optimization)
+		testCfg := params.BeaconConfig().Copy()
+		testCfg.DenebForkEpoch = 0
+		testCfg.ElectraForkEpoch = 100
+		testCfg.FuluForkEpoch = 200
+		testCfg.DeprecatedMaxBlobsPerBlock = 6
+		testCfg.DeprecatedMaxBlobsPerBlockElectra = 9
+		// Define blob schedule with progressive increases
+		testCfg.BlobSchedule = []params.BlobScheduleEntry{
+			{Epoch: 0, MaxBlobsPerBlock: 3},  // Start with 3 blobs
+			{Epoch: 10, MaxBlobsPerBlock: 5}, // Increase to 5 at epoch 10
+			{Epoch: 20, MaxBlobsPerBlock: 7}, // Increase to 7 at epoch 20
+			{Epoch: 30, MaxBlobsPerBlock: 9}, // Increase to 9 at epoch 30
+		}
+		params.OverrideBeaconConfig(testCfg)
+
+		s := &Server{}
+
+		// Test epoch 0-9: max 3 blobs
+		t.Run("epoch 0-9: max 3 blobs", func(t *testing.T) {
+			blk := util.NewBeaconBlockDeneb()
+			blk.Block.Slot = 5 // Epoch 0
+			blk.Block.Body.BlobKzgCommitments = commitments[:3]
+			b, err := blocks.NewSignedBeaconBlock(blk)
+			require.NoError(t, err)
+			require.NoError(t, s.validateBlobSidecars(b, blobs[:3], proofs[:3]))
+
+			// Should fail with 4 blobs
+			blk.Block.Body.BlobKzgCommitments = commitments[:4]
+			b, err = blocks.NewSignedBeaconBlock(blk)
+			require.NoError(t, err)
+			err = s.validateBlobSidecars(b, blobs[:4], proofs[:4])
+			require.ErrorContains(t, "number of blobs over max, 4 > 3", err)
+		})
+
+		// Test epoch 30+: max 9 blobs
+		t.Run("epoch 30+: max 9 blobs", func(t *testing.T) {
+			blk := util.NewBeaconBlockDeneb()
+			blk.Block.Slot = 960 // Epoch 30
+			blk.Block.Body.BlobKzgCommitments = commitments[:9]
+			b, err := blocks.NewSignedBeaconBlock(blk)
+			require.NoError(t, err)
+			require.NoError(t, s.validateBlobSidecars(b, blobs[:9], proofs[:9]))
+
+			// Should fail with 10 blobs
+			blk.Block.Body.BlobKzgCommitments = commitments[:10]
+			b, err = blocks.NewSignedBeaconBlock(blk)
+			require.NoError(t, err)
+			err = s.validateBlobSidecars(b, blobs[:10], proofs[:10])
+			require.ErrorContains(t, "number of blobs over max, 10 > 9", err)
+		})
+	})
 }
 
 func TestGetPendingConsolidations(t *testing.T) {

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

@@ -44,7 +44,7 @@ func (s *Server) GetValidators(w http.ResponseWriter, r *http.Request) {
 
 	isOptimistic, err := helpers.IsOptimistic(ctx, []byte(stateId), s.OptimisticModeFetcher, s.Stater, s.ChainInfoFetcher, s.BeaconDB)
 	if err != nil {
-		httputil.HandleError(w, "Could not check optimistic status: "+err.Error(), http.StatusInternalServerError)
+		helpers.HandleIsOptimisticError(w, err)
 		return
 	}
 	blockRoot, err := st.LatestBlockHeader().HashTreeRoot()
@@ -222,7 +222,7 @@ func (s *Server) GetValidator(w http.ResponseWriter, r *http.Request) {
 
 	isOptimistic, err := helpers.IsOptimistic(ctx, []byte(stateId), s.OptimisticModeFetcher, s.Stater, s.ChainInfoFetcher, s.BeaconDB)
 	if err != nil {
-		httputil.HandleError(w, "Could not check optimistic status: "+err.Error(), http.StatusInternalServerError)
+		helpers.HandleIsOptimisticError(w, err)
 		return
 	}
 	blockRoot, err := st.LatestBlockHeader().HashTreeRoot()
@@ -258,7 +258,7 @@ func (s *Server) GetValidatorBalances(w http.ResponseWriter, r *http.Request) {
 
 	isOptimistic, err := helpers.IsOptimistic(ctx, []byte(stateId), s.OptimisticModeFetcher, s.Stater, s.ChainInfoFetcher, s.BeaconDB)
 	if err != nil {
-		httputil.HandleError(w, "Could not check optimistic status: "+err.Error(), http.StatusInternalServerError)
+		helpers.HandleIsOptimisticError(w, err)
 		return
 	}
 	blockRoot, err := st.LatestBlockHeader().HashTreeRoot()
@@ -419,7 +419,7 @@ func (s *Server) getValidatorIdentitiesJSON(
 ) {
 	isOptimistic, err := helpers.IsOptimistic(ctx, []byte(stateId), s.OptimisticModeFetcher, s.Stater, s.ChainInfoFetcher, s.BeaconDB)
 	if err != nil {
-		httputil.HandleError(w, "Could not check optimistic status: "+err.Error(), http.StatusInternalServerError)
+		helpers.HandleIsOptimisticError(w, err)
 		return
 	}
 	blockRoot, err := st.LatestBlockHeader().HashTreeRoot()

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

@@ -9,7 +9,6 @@ go_library(
         "//api/server/structs:go_default_library",
         "//config/params:go_default_library",
         "//monitoring/tracing/trace:go_default_library",
-        "//network/forks:go_default_library",
         "//network/httputil:go_default_library",
         "@com_github_ethereum_go_ethereum//common/hexutil:go_default_library",
         "@com_github_sirupsen_logrus//:go_default_library",
@@ -24,8 +23,6 @@ go_test(
         "//api/server/structs:go_default_library",
         "//config/params:go_default_library",
         "//consensus-types/primitives:go_default_library",
-        "//encoding/bytesutil:go_default_library",
-        "//network/forks:go_default_library",
         "//testing/assert:go_default_library",
         "//testing/require:go_default_library",
         "@com_github_ethereum_go_ethereum//common:go_default_library",

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

@@ -11,7 +11,6 @@ import (
 	"github.com/OffchainLabs/prysm/v6/api/server/structs"
 	"github.com/OffchainLabs/prysm/v6/config/params"
 	"github.com/OffchainLabs/prysm/v6/monitoring/tracing/trace"
-	"github.com/OffchainLabs/prysm/v6/network/forks"
 	"github.com/OffchainLabs/prysm/v6/network/httputil"
 	"github.com/ethereum/go-ethereum/common/hexutil"
 	log "github.com/sirupsen/logrus"
@@ -35,34 +34,25 @@ func GetForkSchedule(w http.ResponseWriter, r *http.Request) {
 	_, span := trace.StartSpan(r.Context(), "config.GetForkSchedule")
 	defer span.End()
 
-	schedule := params.BeaconConfig().ForkVersionSchedule
+	schedule := params.SortedForkSchedule()
+	data := make([]*structs.Fork, 0, len(schedule))
 	if len(schedule) == 0 {
 		httputil.WriteJson(w, &structs.GetForkScheduleResponse{
-			Data: make([]*structs.Fork, 0),
+			Data: data,
 		})
-		return
 	}
-
-	versions := forks.SortedForkVersions(schedule)
-	chainForks := make([]*structs.Fork, len(schedule))
-	var previous, current []byte
-	for i, v := range versions {
-		if i == 0 {
-			previous = params.BeaconConfig().GenesisForkVersion
-		} else {
-			previous = current
-		}
-		copyV := v
-		current = copyV[:]
-		chainForks[i] = &structs.Fork{
-			PreviousVersion: hexutil.Encode(previous),
-			CurrentVersion:  hexutil.Encode(current),
-			Epoch:           fmt.Sprintf("%d", schedule[v]),
-		}
+	previous := schedule[0]
+	for _, entry := range schedule {
+		data = append(data, &structs.Fork{
+			PreviousVersion: hexutil.Encode(previous.ForkVersion[:]),
+			CurrentVersion:  hexutil.Encode(entry.ForkVersion[:]),
+			Epoch:           fmt.Sprintf("%d", entry.Epoch),
+		})
+		previous = entry
 	}
 
 	httputil.WriteJson(w, &structs.GetForkScheduleResponse{
-		Data: chainForks,
+		Data: data,
 	})
 }
 

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

@@ -13,8 +13,6 @@ import (
 	"github.com/OffchainLabs/prysm/v6/api/server/structs"
 	"github.com/OffchainLabs/prysm/v6/config/params"
 	"github.com/OffchainLabs/prysm/v6/consensus-types/primitives"
-	"github.com/OffchainLabs/prysm/v6/encoding/bytesutil"
-	"github.com/OffchainLabs/prysm/v6/network/forks"
 	"github.com/OffchainLabs/prysm/v6/testing/assert"
 	"github.com/OffchainLabs/prysm/v6/testing/require"
 	"github.com/ethereum/go-ethereum/common"
@@ -592,43 +590,34 @@ func TestGetSpec(t *testing.T) {
 
 func TestForkSchedule_Ok(t *testing.T) {
 	t.Run("ok", func(t *testing.T) {
-		genesisForkVersion := []byte("Genesis")
-		firstForkVersion, firstForkEpoch := []byte("Firs"), primitives.Epoch(100)
-		secondForkVersion, secondForkEpoch := []byte("Seco"), primitives.Epoch(200)
-		thirdForkVersion, thirdForkEpoch := []byte("Thir"), primitives.Epoch(300)
 
 		params.SetupTestConfigCleanup(t)
 		config := params.BeaconConfig().Copy()
-		config.GenesisForkVersion = genesisForkVersion
-		// Create fork schedule adding keys in non-sorted order.
-		schedule := make(map[[4]byte]primitives.Epoch, 3)
-		schedule[bytesutil.ToBytes4(secondForkVersion)] = secondForkEpoch
-		schedule[bytesutil.ToBytes4(firstForkVersion)] = firstForkEpoch
-		schedule[bytesutil.ToBytes4(thirdForkVersion)] = thirdForkEpoch
-		config.ForkVersionSchedule = schedule
-		params.OverrideBeaconConfig(config)
+		config.InitializeForkSchedule()
 
 		request := httptest.NewRequest(http.MethodGet, "http://example.com/eth/v1/config/fork_schedule", nil)
 		writer := httptest.NewRecorder()
 		writer.Body = &bytes.Buffer{}
 
+		genesisStr, firstStr, secondStr := hexutil.Encode(config.GenesisForkVersion), hexutil.Encode(config.AltairForkVersion), hexutil.Encode(config.BellatrixForkVersion)
 		GetForkSchedule(writer, request)
 		require.Equal(t, http.StatusOK, writer.Code)
 		resp := &structs.GetForkScheduleResponse{}
 		require.NoError(t, json.Unmarshal(writer.Body.Bytes(), resp))
-		require.Equal(t, 3, len(resp.Data))
+		schedule := params.SortedForkSchedule()
+		require.Equal(t, len(schedule), len(resp.Data))
 		fork := resp.Data[0]
-		assert.DeepEqual(t, hexutil.Encode(genesisForkVersion), fork.PreviousVersion)
-		assert.DeepEqual(t, hexutil.Encode(firstForkVersion), fork.CurrentVersion)
-		assert.Equal(t, fmt.Sprintf("%d", firstForkEpoch), fork.Epoch)
+		assert.Equal(t, genesisStr, fork.PreviousVersion)
+		assert.Equal(t, genesisStr, fork.CurrentVersion)
+		assert.Equal(t, fmt.Sprintf("%d", config.GenesisEpoch), fork.Epoch)
 		fork = resp.Data[1]
-		assert.DeepEqual(t, hexutil.Encode(firstForkVersion), fork.PreviousVersion)
-		assert.DeepEqual(t, hexutil.Encode(secondForkVersion), fork.CurrentVersion)
-		assert.Equal(t, fmt.Sprintf("%d", secondForkEpoch), fork.Epoch)
+		assert.Equal(t, genesisStr, fork.PreviousVersion)
+		assert.Equal(t, firstStr, fork.CurrentVersion)
+		assert.Equal(t, fmt.Sprintf("%d", config.AltairForkEpoch), fork.Epoch)
 		fork = resp.Data[2]
-		assert.DeepEqual(t, hexutil.Encode(secondForkVersion), fork.PreviousVersion)
-		assert.DeepEqual(t, hexutil.Encode(thirdForkVersion), fork.CurrentVersion)
-		assert.Equal(t, fmt.Sprintf("%d", thirdForkEpoch), fork.Epoch)
+		assert.Equal(t, firstStr, fork.PreviousVersion)
+		assert.Equal(t, secondStr, fork.CurrentVersion)
+		assert.Equal(t, fmt.Sprintf("%d", config.BellatrixForkEpoch), fork.Epoch)
 	})
 	t.Run("correct number of forks", func(t *testing.T) {
 		request := httptest.NewRequest(http.MethodGet, "http://example.com/eth/v1/config/fork_schedule", nil)
@@ -639,8 +628,8 @@ func TestForkSchedule_Ok(t *testing.T) {
 		require.Equal(t, http.StatusOK, writer.Code)
 		resp := &structs.GetForkScheduleResponse{}
 		require.NoError(t, json.Unmarshal(writer.Body.Bytes(), resp))
-		os := forks.NewOrderedSchedule(params.BeaconConfig())
-		assert.Equal(t, os.Len(), len(resp.Data))
+		os := params.SortedForkSchedule()
+		assert.Equal(t, len(os), len(resp.Data))
 	})
 }
 

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

@@ -46,7 +46,7 @@ func (s *Server) getBeaconStateV2(ctx context.Context, w http.ResponseWriter, id
 
 	isOptimistic, err := helpers.IsOptimistic(ctx, id, s.OptimisticModeFetcher, s.Stater, s.ChainInfoFetcher, s.BeaconDB)
 	if err != nil {
-		httputil.HandleError(w, "Could not check if state is optimistic: "+err.Error(), http.StatusInternalServerError)
+		helpers.HandleIsOptimisticError(w, err)
 		return
 	}
 	blockRoot, err := st.LatestBlockHeader().HashTreeRoot()

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

@@ -12,6 +12,7 @@ go_library(
     deps = [
         "//beacon-chain/blockchain:go_default_library",
         "//beacon-chain/db:go_default_library",
+        "//beacon-chain/rpc/eth/shared:go_default_library",
         "//beacon-chain/rpc/lookup:go_default_library",
         "//beacon-chain/state:go_default_library",
         "//beacon-chain/state/stategen:go_default_library",
@@ -21,6 +22,7 @@ go_library(
         "//consensus-types/primitives:go_default_library",
         "//consensus-types/validator:go_default_library",
         "//encoding/bytesutil:go_default_library",
+        "//network/httputil:go_default_library",
         "//time/slots:go_default_library",
         "@com_github_ethereum_go_ethereum//common/hexutil:go_default_library",
         "@com_github_pkg_errors//:go_default_library",
@@ -40,6 +42,7 @@ go_test(
         "//beacon-chain/blockchain/testing:go_default_library",
         "//beacon-chain/db/testing:go_default_library",
         "//beacon-chain/forkchoice/doubly-linked-tree:go_default_library",
+        "//beacon-chain/rpc/lookup:go_default_library",
         "//beacon-chain/rpc/testutil:go_default_library",
         "//beacon-chain/state:go_default_library",
         "//beacon-chain/state/state-native:go_default_library",
@@ -57,5 +60,6 @@ go_test(
         "//testing/require:go_default_library",
         "//testing/util:go_default_library",
         "@com_github_ethereum_go_ethereum//common/hexutil:go_default_library",
+        "@com_github_pkg_errors//:go_default_library",
     ],
 )

beacon-chain/rpc/eth/helpers/error_handling.go

@@ -2,11 +2,14 @@ package helpers
 
 import (
 	"errors"
+	"net/http"
 
+	"github.com/OffchainLabs/prysm/v6/beacon-chain/rpc/eth/shared"
 	"github.com/OffchainLabs/prysm/v6/beacon-chain/rpc/lookup"
 	"github.com/OffchainLabs/prysm/v6/beacon-chain/state/stategen"
 	"github.com/OffchainLabs/prysm/v6/consensus-types/blocks"
 	"github.com/OffchainLabs/prysm/v6/consensus-types/interfaces"
+	"github.com/OffchainLabs/prysm/v6/network/httputil"
 	"google.golang.org/grpc/codes"
 	"google.golang.org/grpc/status"
 )
@@ -28,6 +31,22 @@ func PrepareStateFetchGRPCError(err error) error {
 	return status.Errorf(codes.Internal, "Invalid state ID: %v", err)
 }
 
+// HandleIsOptimisticError handles errors from IsOptimistic function calls and writes appropriate HTTP responses.
+func HandleIsOptimisticError(w http.ResponseWriter, err error) {
+	var fetchErr *lookup.FetchStateError
+	if errors.As(err, &fetchErr) {
+		shared.WriteStateFetchError(w, err)
+		return
+	}
+
+	var blockRootsNotFoundErr *lookup.BlockRootsNotFoundError
+	if errors.As(err, &blockRootsNotFoundErr) {
+		httputil.HandleError(w, "Could not check optimistic status: "+err.Error(), http.StatusNotFound)
+		return
+	}
+	httputil.HandleError(w, "Could not check optimistic status: "+err.Error(), http.StatusInternalServerError)
+}
+
 // IndexedVerificationFailure represents a collection of verification failures.
 type IndexedVerificationFailure struct {
 	Failures []*SingleIndexedVerificationFailure `json:"failures"`

beacon-chain/rpc/eth/helpers/sync.go

@@ -56,7 +56,8 @@ func IsOptimistic(
 		if bytesutil.IsHex(stateId) {
 			id, err := hexutil.Decode(stateIdString)
 			if err != nil {
-				return false, err
+				e := lookup.NewStateIdParseError(err)
+				return false, &e
 			}
 			return isStateRootOptimistic(ctx, id, optimisticModeFetcher, stateFetcher, chainInfo, database)
 		} else if len(stateId) == 32 {
@@ -127,7 +128,7 @@ func isStateRootOptimistic(
 ) (bool, error) {
 	st, err := stateFetcher.State(ctx, stateId)
 	if err != nil {
-		return true, errors.Wrap(err, "could not fetch state")
+		return true, lookup.NewFetchStateError(err)
 	}
 	if st.Slot() == chainInfo.HeadSlot() {
 		return optimisticModeFetcher.IsOptimistic(ctx)
@@ -137,7 +138,7 @@ func isStateRootOptimistic(
 		return true, errors.Wrapf(err, "could not get block roots for slot %d", st.Slot())
 	}
 	if !has {
-		return true, errors.New("no block roots returned from the database")
+		return true, lookup.NewBlockRootsNotFoundError()
 	}
 	for _, r := range roots {
 		b, err := database.Block(ctx, r)

beacon-chain/rpc/eth/helpers/sync_test.go

@@ -1,12 +1,15 @@
 package helpers
 
 import (
+	"net/http"
+	"net/http/httptest"
 	"strconv"
 	"testing"
 
 	chainmock "github.com/OffchainLabs/prysm/v6/beacon-chain/blockchain/testing"
 	dbtest "github.com/OffchainLabs/prysm/v6/beacon-chain/db/testing"
 	doublylinkedtree "github.com/OffchainLabs/prysm/v6/beacon-chain/forkchoice/doubly-linked-tree"
+	"github.com/OffchainLabs/prysm/v6/beacon-chain/rpc/lookup"
 	"github.com/OffchainLabs/prysm/v6/beacon-chain/rpc/testutil"
 	"github.com/OffchainLabs/prysm/v6/beacon-chain/state"
 	state_native "github.com/OffchainLabs/prysm/v6/beacon-chain/state/state-native"
@@ -21,6 +24,7 @@ import (
 	"github.com/OffchainLabs/prysm/v6/testing/require"
 	"github.com/OffchainLabs/prysm/v6/testing/util"
 	"github.com/ethereum/go-ethereum/common/hexutil"
+	"github.com/pkg/errors"
 )
 
 func TestIsOptimistic(t *testing.T) {
@@ -226,7 +230,67 @@ func TestIsOptimistic(t *testing.T) {
 			require.NoError(t, err)
 			assert.Equal(t, true, o)
 		})
+		t.Run("State not found", func(t *testing.T) {
+			b, err := blocks.NewSignedBeaconBlock(util.NewBeaconBlock())
+			require.NoError(t, err)
+			b.SetStateRoot(bytesutil.PadTo([]byte("root"), 32))
+			db := dbtest.SetupDB(t)
+			require.NoError(t, db.SaveBlock(ctx, b))
+			chainSt, err := util.NewBeaconState()
+			require.NoError(t, err)
+			require.NoError(t, chainSt.SetSlot(fieldparams.SlotsPerEpoch))
+			bRoot, err := b.Block().HashTreeRoot()
+			require.NoError(t, err)
+			cs := &chainmock.ChainService{State: chainSt, OptimisticRoots: map[[32]byte]bool{bRoot: true}}
+			mf := &testutil.MockStater{
+				CustomError: lookup.NewFetchStateError(nil),
+			}
+			_, err = IsOptimistic(ctx, []byte(hexutil.Encode(bytesutil.PadTo([]byte("root"), 32))), cs, mf, cs, db)
+			var fetchErr *lookup.FetchStateError
+			require.Equal(t, true, errors.As(err, &fetchErr))
+		})
+
+		t.Run("stateId invalid", func(t *testing.T) {
+			b, err := blocks.NewSignedBeaconBlock(util.NewBeaconBlock())
+			require.NoError(t, err)
+			b.SetStateRoot(bytesutil.PadTo([]byte("root"), 32))
+			db := dbtest.SetupDB(t)
+			require.NoError(t, db.SaveBlock(ctx, b))
+			chainSt, err := util.NewBeaconState()
+			require.NoError(t, err)
+			require.NoError(t, chainSt.SetSlot(fieldparams.SlotsPerEpoch))
+			bRoot, err := b.Block().HashTreeRoot()
+			require.NoError(t, err)
+			cs := &chainmock.ChainService{State: chainSt, OptimisticRoots: map[[32]byte]bool{bRoot: true}}
+			mf := &testutil.MockStater{
+				CustomError: lookup.NewFetchStateError(nil),
+			}
+			_, err = IsOptimistic(ctx, []byte("0xabc"), cs, mf, cs, db)
+			var fetchErr *lookup.FetchStateError
+			require.Equal(t, false, errors.As(err, &fetchErr))
+		})
+		t.Run("block roots not found", func(t *testing.T) {
+			b, err := blocks.NewSignedBeaconBlock(util.NewBeaconBlock())
+			require.NoError(t, err)
+			b.SetStateRoot(bytesutil.PadTo([]byte("root"), 32))
+			db := dbtest.SetupDB(t)
+			require.NoError(t, db.SaveBlock(ctx, b))
+			chainSt, err := util.NewBeaconState()
+			require.NoError(t, err)
+			require.NoError(t, chainSt.SetSlot(fieldparams.SlotsPerEpoch))
+			bRoot, err := b.Block().HashTreeRoot()
+			require.NoError(t, err)
+			cs := &chainmock.ChainService{State: chainSt, OptimisticRoots: map[[32]byte]bool{bRoot: true}}
+			st, err := util.NewBeaconState()
+			require.NoError(t, st.SetSlot(primitives.Slot(fieldparams.SlotsPerEpoch+1)))
+			require.NoError(t, err)
+			mf := &testutil.MockStater{BeaconState: st}
+			_, err = IsOptimistic(ctx, []byte(hexutil.Encode(bytesutil.PadTo([]byte("root"), 32))), cs, mf, cs, db)
+			var blockRootsNotFoundErr *lookup.BlockRootsNotFoundError
+			require.Equal(t, true, errors.As(err, &blockRootsNotFoundErr))
+		})
 	})
+
 	t.Run("slot", func(t *testing.T) {
 		t.Run("head is not optimistic", func(t *testing.T) {
 			cs := &chainmock.ChainService{Optimistic: false}
@@ -319,6 +383,36 @@ func TestIsOptimistic(t *testing.T) {
 	})
 }
 
+func TestHandleIsOptimisticError(t *testing.T) {
+	t.Run("fetch-state error handled as 404", func(t *testing.T) {
+		rr := httptest.NewRecorder()
+		notFoundErr := lookup.StateNotFoundError{}
+		fetchErr := lookup.NewFetchStateError(&notFoundErr)
+		HandleIsOptimisticError(rr, fetchErr)
+
+		require.Equal(t, http.StatusNotFound, rr.Code)
+		require.StringContains(t, notFoundErr.Error(), rr.Body.String())
+	})
+	t.Run("no block roots error handled as 404", func(t *testing.T) {
+		rr := httptest.NewRecorder()
+		blockRootsErr := lookup.NewBlockRootsNotFoundError()
+		HandleIsOptimisticError(rr, blockRootsErr)
+
+		require.Equal(t, http.StatusNotFound, rr.Code)
+		require.StringContains(t, blockRootsErr.Error(), rr.Body.String())
+	})
+
+	t.Run("generic error handled as 500", func(t *testing.T) {
+		rr := httptest.NewRecorder()
+		genericErr := errors.New("boom")
+
+		HandleIsOptimisticError(rr, genericErr)
+
+		require.Equal(t, http.StatusInternalServerError, rr.Code)
+		require.StringContains(t, "Could not check optimistic status: boom", rr.Body.String())
+	})
+}
+
 // prepareForkchoiceState prepares a beacon state with the given data to mock
 // insert into forkchoice
 func prepareForkchoiceState(

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

@@ -12,12 +12,10 @@ go_library(
         "//api:go_default_library",
         "//api/server/structs:go_default_library",
         "//beacon-chain/core/light-client:go_default_library",
-        "//beacon-chain/core/signing:go_default_library",
         "//beacon-chain/rpc/eth/shared:go_default_library",
         "//config/params:go_default_library",
         "//encoding/bytesutil:go_default_library",
         "//monitoring/tracing/trace:go_default_library",
-        "//network/forks:go_default_library",
         "//network/httputil:go_default_library",
         "//runtime/version:go_default_library",
         "//time/slots:go_default_library",

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

@@ -7,12 +7,10 @@ import (
 	"github.com/OffchainLabs/prysm/v6/api"
 	"github.com/OffchainLabs/prysm/v6/api/server/structs"
 	lightclient "github.com/OffchainLabs/prysm/v6/beacon-chain/core/light-client"
-	"github.com/OffchainLabs/prysm/v6/beacon-chain/core/signing"
 	"github.com/OffchainLabs/prysm/v6/beacon-chain/rpc/eth/shared"
 	"github.com/OffchainLabs/prysm/v6/config/params"
 	"github.com/OffchainLabs/prysm/v6/encoding/bytesutil"
 	"github.com/OffchainLabs/prysm/v6/monitoring/tracing/trace"
-	"github.com/OffchainLabs/prysm/v6/network/forks"
 	"github.com/OffchainLabs/prysm/v6/network/httputil"
 	"github.com/OffchainLabs/prysm/v6/runtime/version"
 	"github.com/OffchainLabs/prysm/v6/time/slots"
@@ -111,17 +109,7 @@ func (s *Server) GetLightClientUpdatesByRange(w http.ResponseWriter, req *http.R
 
 			updateSlot := update.AttestedHeader().Beacon().Slot
 			updateEpoch := slots.ToEpoch(updateSlot)
-			updateFork, err := forks.Fork(updateEpoch)
-			if err != nil {
-				httputil.HandleError(w, "Could not get fork Version: "+err.Error(), http.StatusInternalServerError)
-				return
-			}
-
-			forkDigest, err := signing.ComputeForkDigest(updateFork.CurrentVersion, params.BeaconConfig().GenesisValidatorsRoot[:])
-			if err != nil {
-				httputil.HandleError(w, "Could not compute fork digest: "+err.Error(), http.StatusInternalServerError)
-				return
-			}
+			updateEntry := params.GetNetworkScheduleEntry(updateEpoch)
 			updateSSZ, err := update.MarshalSSZ()
 			if err != nil {
 				httputil.HandleError(w, "Could not marshal update to SSZ: "+err.Error(), http.StatusInternalServerError)
@@ -133,7 +121,7 @@ func (s *Server) GetLightClientUpdatesByRange(w http.ResponseWriter, req *http.R
 			if _, err := w.Write(chunkLength); err != nil {
 				httputil.HandleError(w, "Could not write chunk length: "+err.Error(), http.StatusInternalServerError)
 			}
-			if _, err := w.Write(forkDigest[:]); err != nil {
+			if _, err := w.Write(updateEntry.ForkDigest[:]); err != nil {
 				httputil.HandleError(w, "Could not write fork digest: "+err.Error(), http.StatusInternalServerError)
 			}
 			if _, err := w.Write(updateSSZ); err != nil {

beacon-chain/rpc/lookup/blocker.go

@@ -23,6 +23,20 @@ import (
 	"github.com/pkg/errors"
 )
 
+type BlockRootsNotFoundError struct {
+	message string
+}
+
+func NewBlockRootsNotFoundError() *BlockRootsNotFoundError {
+	return &BlockRootsNotFoundError{
+		message: "no block roots returned from the database",
+	}
+}
+
+func (e BlockRootsNotFoundError) Error() string {
+	return e.message
+}
+
 // BlockIdParseError represents an error scenario where a block ID could not be parsed.
 type BlockIdParseError struct {
 	message string
@@ -341,7 +355,7 @@ func (p *BeaconDbBlocker) blobsFromStoredDataColumns(block blocks.ROBlock, indic
 	stored := summary.Stored()
 	count := uint64(len(stored))
 
-	if count < peerdas.MinimumColumnsCountToReconstruct() {
+	if count < peerdas.MinimumColumnCountToReconstruct() {
 		// There is no way to reconstruct the data columns.
 		return nil, &core.RpcError{
 			Err:    errors.Errorf("the node does not custody enough data columns to reconstruct blobs - please start the beacon node with the `--%s` flag to ensure this call to succeed, or retry later if it is already the case", flags.SubscribeAllDataSubnets.Name),

beacon-chain/rpc/lookup/blocker_test.go

@@ -443,7 +443,7 @@ func TestGetBlob(t *testing.T) {
 		setupFulu(t)
 
 		_, dataColumnStorage := filesystem.NewEphemeralDataColumnStorageAndFs(t)
-		err = dataColumnStorage.Save(verifiedRoDataColumnSidecars[1 : peerdas.MinimumColumnsCountToReconstruct()+1])
+		err = dataColumnStorage.Save(verifiedRoDataColumnSidecars[1 : peerdas.MinimumColumnCountToReconstruct()+1])
 		require.NoError(t, err)
 
 		blocker := &BeaconDbBlocker{

beacon-chain/rpc/lookup/stater.go

@@ -21,6 +21,27 @@ import (
 	"github.com/pkg/errors"
 )
 
+type FetchStateError struct {
+	message string
+	cause   error
+}
+
+func NewFetchStateError(cause error) *FetchStateError {
+	return &FetchStateError{
+		message: "could not fetch state",
+		cause:   cause,
+	}
+}
+
+func (e *FetchStateError) Error() string {
+	if e.cause != nil {
+		return e.message + ": " + e.cause.Error()
+	}
+	return e.message
+}
+
+func (e *FetchStateError) Unwrap() error { return e.cause }
+
 // StateIdParseError represents an error scenario where a state ID could not be parsed.
 type StateIdParseError struct {
 	message string

beacon-chain/rpc/prysm/beacon/validator_count.go

@@ -56,11 +56,7 @@ func (s *Server) GetValidatorCount(w http.ResponseWriter, r *http.Request) {
 
 	isOptimistic, err := helpers.IsOptimistic(ctx, []byte(stateID), s.OptimisticModeFetcher, s.Stater, s.ChainInfoFetcher, s.BeaconDB)
 	if err != nil {
-		errJson := &httputil.DefaultJsonError{
-			Message: fmt.Sprintf("could not check if slot's block is optimistic: %v", err),
-			Code:    http.StatusInternalServerError,
-		}
-		httputil.WriteError(w, errJson)
+		helpers.HandleIsOptimisticError(w, err)
 		return
 	}
 

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

@@ -19,7 +19,10 @@ func (_ *Server) GetBeaconConfig(_ context.Context, _ *emptypb.Empty) (*ethpb.Be
 	numFields := val.Type().NumField()
 	res := make(map[string]string, numFields)
 	for i := 0; i < numFields; i++ {
-		res[val.Type().Field(i).Name] = fmt.Sprintf("%v", val.Field(i).Interface())
+		field := val.Type().Field(i)
+		if field.IsExported() {
+			res[field.Name] = fmt.Sprintf("%v", val.Field(i).Interface())
+		}
 	}
 	return &ethpb.BeaconConfig{
 		Config: res,

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

@@ -17,10 +17,19 @@ func TestServer_GetBeaconConfig(t *testing.T) {
 	res, err := bs.GetBeaconConfig(ctx, &emptypb.Empty{})
 	require.NoError(t, err)
 	conf := params.BeaconConfig()
-	numFields := reflect.TypeOf(conf).Elem().NumField()
+	confType := reflect.TypeOf(conf).Elem()
+	numFields := confType.NumField()
+	
+	// Count only exported fields, as unexported fields are not included in the config
+	exportedFields := 0
+	for i := 0; i < numFields; i++ {
+		if confType.Field(i).IsExported() {
+			exportedFields++
+		}
+	}
 
-	// Check if the result has the same number of items as our config struct.
-	assert.Equal(t, numFields, len(res.Config), "Unexpected number of items in config")
+	// Check if the result has the same number of items as exported fields in our config struct.
+	assert.Equal(t, exportedFields, len(res.Config), "Unexpected number of items in config")
 	want := fmt.Sprintf("%d", conf.Eth1FollowDistance)
 
 	// Check that an element is properly populated from the config.

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

@@ -81,10 +81,10 @@ go_library(
         "//crypto/rand:go_default_library",
         "//encoding/bytesutil:go_default_library",
         "//encoding/ssz:go_default_library",
+	"//genesis:go_default_library",
         "//math:go_default_library",
         "//monitoring/tracing:go_default_library",
         "//monitoring/tracing/trace:go_default_library",
-        "//network/forks:go_default_library",
         "//proto/engine/v1:go_default_library",
         "//proto/eth/v1:go_default_library",
         "//proto/prysm/v1alpha1:go_default_library",
@@ -155,6 +155,7 @@ common_deps = [
     "//crypto/bls/blst:go_default_library",
     "//encoding/bytesutil:go_default_library",
     "//encoding/ssz:go_default_library",
+    "//genesis:go_default_library",
     "//proto/engine/v1:go_default_library",
     "//proto/eth/v1:go_default_library",
     "//proto/prysm/v1alpha1:go_default_library",

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

@@ -248,6 +248,8 @@ func (vs *Server) sendBlocks(stream ethpb.BeaconNodeValidator_StreamBlocksAltair
 		b.Block = &ethpb.StreamBlocksResponse_DenebBlock{DenebBlock: p}
 	case *ethpb.SignedBeaconBlockElectra:
 		b.Block = &ethpb.StreamBlocksResponse_ElectraBlock{ElectraBlock: p}
+	case *ethpb.SignedBeaconBlockFulu:
+		b.Block = &ethpb.StreamBlocksResponse_FuluBlock{FuluBlock: p}
 	default:
 		log.Errorf("Unknown block type %T", p)
 	}

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

@@ -381,3 +381,92 @@ func TestServer_StreamSlotsVerified_OnHeadUpdated(t *testing.T) {
 	}
 	<-exitRoutine
 }
+
+func TestServer_StreamBlocksVerified_FuluBlock(t *testing.T) {
+	db := dbTest.SetupDB(t)
+	ctx := t.Context()
+	beaconState, privs := util.DeterministicGenesisStateFulu(t, 32)
+	c, err := altair.NextSyncCommittee(ctx, beaconState)
+	require.NoError(t, err)
+	require.NoError(t, beaconState.SetCurrentSyncCommittee(c))
+
+	b, err := util.GenerateFullBlockFulu(beaconState, privs, util.DefaultBlockGenConfig(), 1)
+	require.NoError(t, err)
+	r, err := b.Block.HashTreeRoot()
+	require.NoError(t, err)
+	wrappedBlk := util.SaveBlock(t, ctx, db, b)
+	chainService := &chainMock.ChainService{State: beaconState}
+	server := &Server{
+		Ctx:           ctx,
+		StateNotifier: chainService.StateNotifier(),
+		HeadFetcher:   chainService,
+	}
+	exitRoutine := make(chan bool)
+	ctrl := gomock.NewController(t)
+	defer ctrl.Finish()
+	mockStream := mock.NewMockBeaconNodeValidatorAltair_StreamBlocksServer(ctrl)
+	mockStream.EXPECT().Send(&ethpb.StreamBlocksResponse{Block: &ethpb.StreamBlocksResponse_FuluBlock{FuluBlock: b}}).Do(func(arg0 interface{}) {
+		exitRoutine <- true
+	})
+	mockStream.EXPECT().Context().Return(ctx).AnyTimes()
+
+	go func(tt *testing.T) {
+		err := server.StreamBlocksAltair(&ethpb.StreamBlocksRequest{VerifiedOnly: true}, mockStream)
+		if s, _ := status.FromError(err); s.Code() != codes.Canceled {
+			assert.NoError(tt, err)
+		}
+	}(t)
+	// Send in a loop to ensure it is delivered (busy wait for the service to subscribe to the state feed).
+	for sent := 0; sent == 0; {
+		sent = server.StateNotifier.StateFeed().Send(&feed.Event{
+			Type: statefeed.BlockProcessed,
+			Data: &statefeed.BlockProcessedData{Slot: b.Block.Slot, BlockRoot: r, SignedBlock: wrappedBlk},
+		})
+	}
+	<-exitRoutine
+}
+
+func TestServer_StreamBlocks_FuluBlock(t *testing.T) {
+	params.SetupTestConfigCleanup(t)
+	params.OverrideBeaconConfig(params.BeaconConfig())
+	ctx := t.Context()
+	beaconState, privs := util.DeterministicGenesisStateFulu(t, 64)
+	c, err := altair.NextSyncCommittee(ctx, beaconState)
+	require.NoError(t, err)
+	require.NoError(t, beaconState.SetCurrentSyncCommittee(c))
+
+	b, err := util.GenerateFullBlockFulu(beaconState, privs, util.DefaultBlockGenConfig(), 1)
+	require.NoError(t, err)
+	chainService := &chainMock.ChainService{State: beaconState}
+	server := &Server{
+		Ctx:           ctx,
+		BlockNotifier: chainService.BlockNotifier(),
+		HeadFetcher:   chainService,
+	}
+	exitRoutine := make(chan bool)
+	ctrl := gomock.NewController(t)
+	defer ctrl.Finish()
+	mockStream := mock.NewMockBeaconNodeValidatorAltair_StreamBlocksServer(ctrl)
+
+	mockStream.EXPECT().Send(&ethpb.StreamBlocksResponse{Block: &ethpb.StreamBlocksResponse_FuluBlock{FuluBlock: b}}).Do(func(arg0 interface{}) {
+		exitRoutine <- true
+	})
+	mockStream.EXPECT().Context().Return(ctx).AnyTimes()
+
+	go func(tt *testing.T) {
+		err := server.StreamBlocksAltair(&ethpb.StreamBlocksRequest{}, mockStream)
+		if s, _ := status.FromError(err); s.Code() != codes.Canceled {
+			assert.NoError(tt, err)
+		}
+	}(t)
+	wrappedBlk, err := blocks.NewSignedBeaconBlock(b)
+	require.NoError(t, err)
+	// Send in a loop to ensure it is delivered (busy wait for the service to subscribe to the state feed).
+	for sent := 0; sent == 0; {
+		sent = server.BlockNotifier.BlockFeed().Send(&feed.Event{
+			Type: blockfeed.ReceivedBlock,
+			Data: &blockfeed.ReceivedBlockData{SignedBlock: wrappedBlk},
+		})
+	}
+	<-exitRoutine
+}

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

@@ -564,7 +564,7 @@ func TestBuildValidatorAssignmentMap(t *testing.T) {
 	start := primitives.Slot(200)
 	bySlot := [][][]primitives.ValidatorIndex{
 		{{1, 2, 3}},        // slot 200, committee 0
-		{{7, 8, 9}},        // slot 201, committee 0  
+		{{7, 8, 9}},        // slot 201, committee 0
 		{{4, 5}, {10, 11}}, // slot 202, committee 0 & 1
 	}
 
@@ -632,7 +632,7 @@ func TestGetValidatorAssignment_WithAssignmentMap(t *testing.T) {
 	}
 
 	vs := &Server{}
-	
+
 	// Test existing validator (validator 2 is at position 1 in the committee, not position 2)
 	assignment := vs.getValidatorAssignment(meta, primitives.ValidatorIndex(2))
 	require.NotNil(t, assignment)
@@ -662,7 +662,7 @@ func TestGetValidatorAssignment_WithoutAssignmentMap(t *testing.T) {
 	}
 
 	vs := &Server{}
-	
+
 	// Test existing validator
 	assignment := vs.getValidatorAssignment(meta, primitives.ValidatorIndex(5))
 	require.NotNil(t, assignment)
@@ -682,24 +682,24 @@ func TestLoadMetadata_ThresholdBehavior(t *testing.T) {
 	epoch := primitives.Epoch(0)
 
 	tests := []struct {
-		name                    string
-		numValidators          int
-		expectAssignmentMap    bool
+		name                string
+		numValidators       int
+		expectAssignmentMap bool
 	}{
 		{
-			name:                    "Small request - below threshold",
-			numValidators:          100,
-			expectAssignmentMap:    false,
+			name:                "Small request - below threshold",
+			numValidators:       100,
+			expectAssignmentMap: false,
 		},
 		{
-			name:                    "Large request - at threshold",
-			numValidators:          validatorLookupThreshold,
-			expectAssignmentMap:    true,
+			name:                "Large request - at threshold",
+			numValidators:       validatorLookupThreshold,
+			expectAssignmentMap: true,
 		},
 		{
-			name:                    "Large request - above threshold", 
-			numValidators:          validatorLookupThreshold + 1000,
-			expectAssignmentMap:    true,
+			name:                "Large request - above threshold",
+			numValidators:       validatorLookupThreshold + 1000,
+			expectAssignmentMap: true,
 		},
 	}
 

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

@@ -286,6 +286,19 @@ 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)
 	}
+	root, err := block.Block().HashTreeRoot()
+	if err != nil {
+		return nil, status.Errorf(codes.Internal, "Could not hash tree root: %v", err)
+	}
+
+	// For post-Fulu blinded blocks, submit to relay and return early
+	if block.IsBlinded() && slots.ToEpoch(block.Block().Slot()) >= params.BeaconConfig().FuluForkEpoch {
+		err := vs.BlockBuilder.SubmitBlindedBlockPostFulu(ctx, block)
+		if err != nil {
+			return nil, status.Errorf(codes.Internal, "Could not submit blinded block post-Fulu: %v", err)
+		}
+		return &ethpb.ProposeResponse{BlockRoot: root[:]}, nil
+	}
 
 	var sidecars []*ethpb.BlobSidecar
 	if block.IsBlinded() {
@@ -297,11 +310,6 @@ func (vs *Server) ProposeBeaconBlock(ctx context.Context, req *ethpb.GenericSign
 		return nil, status.Errorf(codes.Internal, "%s: %v", "handle block failed", err)
 	}
 
-	root, err := block.Block().HashTreeRoot()
-	if err != nil {
-		return nil, status.Errorf(codes.Internal, "Could not hash tree root: %v", err)
-	}
-
 	var wg sync.WaitGroup
 	errChan := make(chan error, 1)
 
@@ -327,7 +335,8 @@ func (vs *Server) ProposeBeaconBlock(ctx context.Context, req *ethpb.GenericSign
 	return &ethpb.ProposeResponse{BlockRoot: root[:]}, nil
 }
 
-// handleBlindedBlock processes blinded beacon blocks.
+// handleBlindedBlock processes blinded beacon blocks (pre-Fulu only).
+// Post-Fulu blinded blocks are handled directly in ProposeBeaconBlock.
 func (vs *Server) handleBlindedBlock(ctx context.Context, block interfaces.SignedBeaconBlock) (interfaces.SignedBeaconBlock, []*ethpb.BlobSidecar, error) {
 	if block.Version() < version.Bellatrix {
 		return nil, nil, errors.New("pre-Bellatrix blinded block")

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

@@ -18,7 +18,6 @@ import (
 	"github.com/OffchainLabs/prysm/v6/encoding/ssz"
 	"github.com/OffchainLabs/prysm/v6/monitoring/tracing"
 	"github.com/OffchainLabs/prysm/v6/monitoring/tracing/trace"
-	"github.com/OffchainLabs/prysm/v6/network/forks"
 	enginev1 "github.com/OffchainLabs/prysm/v6/proto/engine/v1"
 	"github.com/OffchainLabs/prysm/v6/runtime/version"
 	"github.com/OffchainLabs/prysm/v6/time/slots"
@@ -220,16 +219,11 @@ func (vs *Server) getPayloadHeaderFromBuilder(
 		return nil, errors.New("builder returned nil bid")
 	}
 	bidVersion := signedBid.Version()
-	fork, err := forks.Fork(slots.ToEpoch(slot))
-	if err != nil {
-		return nil, errors.Wrap(err, "unable to get fork information")
-	}
-	forkVersion, ok := params.ConfigForkVersions(params.BeaconConfig())[bytesutil.ToBytes4(fork.CurrentVersion)]
-	if !ok {
-		return nil, errors.New("unable to find current fork in schedule")
-	}
+	epoch := slots.ToEpoch(slot)
+	entry := params.GetNetworkScheduleEntry(epoch)
+	forkVersion := entry.VersionEnum
 	if !isVersionCompatible(bidVersion, forkVersion) {
-		return nil, fmt.Errorf("builder bid response version: %d is not compatible with expected version: %d for epoch %d", bidVersion, forkVersion, slots.ToEpoch(slot))
+		return nil, fmt.Errorf("builder bid response version: %d is not compatible with expected version: %d for epoch %d", bidVersion, forkVersion, epoch)
 	}
 
 	bid, err := signedBid.Message()

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

@@ -3286,3 +3286,252 @@ func TestProposer_ElectraBlobsAndProofs(t *testing.T) {
 	require.Equal(t, 10, len(blobs))
 	require.Equal(t, 10, len(proofs))
 }
+
+func TestServer_ProposeBeaconBlock_PostFuluBlindedBlock(t *testing.T) {
+	db := dbutil.SetupDB(t)
+	ctx := t.Context()
+
+	beaconState, parentRoot, _ := util.DeterministicGenesisStateWithGenesisBlock(t, ctx, db, 100)
+	require.NoError(t, beaconState.SetSlot(1))
+
+	t.Run("post-Fulu blinded block - early return success", func(t *testing.T) {
+		// Set up config with Fulu fork at epoch 5
+		params.SetupTestConfigCleanup(t)
+		cfg := params.BeaconConfig().Copy()
+		cfg.FuluForkEpoch = 5
+		params.OverrideBeaconConfig(cfg)
+
+		mockBuilder := &builderTest.MockBuilderService{
+			HasConfigured:                 true,
+			Cfg:                           &builderTest.Config{BeaconDB: db},
+			ErrSubmitBlindedBlockPostFulu: nil, // Success case
+		}
+
+		c := &mock.ChainService{State: beaconState, Root: parentRoot[:]}
+		proposerServer := &Server{
+			ChainStartFetcher: &mockExecution.Chain{},
+			Eth1InfoFetcher:   &mockExecution.Chain{},
+			Eth1BlockFetcher:  &mockExecution.Chain{},
+			BlockReceiver:     c,
+			BlobReceiver:      c,
+			HeadFetcher:       c,
+			BlockNotifier:     c.BlockNotifier(),
+			OperationNotifier: c.OperationNotifier(),
+			StateGen:          stategen.New(db, doublylinkedtree.New()),
+			TimeFetcher:       c,
+			SyncChecker:       &mockSync.Sync{IsSyncing: false},
+			BeaconDB:          db,
+			BlockBuilder:      mockBuilder,
+			P2P:               &mockp2p.MockBroadcaster{},
+		}
+
+		// Create a blinded block at slot 160 (epoch 5, which is >= FuluForkEpoch)
+		blindedBlock := util.NewBlindedBeaconBlockDeneb()
+		blindedBlock.Message.Slot = 160 // This puts us at epoch 5 (160/32 = 5)
+		blindedBlock.Message.ProposerIndex = 0
+		blindedBlock.Message.ParentRoot = parentRoot[:]
+		blindedBlock.Message.StateRoot = make([]byte, 32)
+
+		req := &ethpb.GenericSignedBeaconBlock{
+			Block: &ethpb.GenericSignedBeaconBlock_BlindedDeneb{BlindedDeneb: blindedBlock},
+		}
+
+		// This should trigger the post-Fulu early return path
+		res, err := proposerServer.ProposeBeaconBlock(ctx, req)
+		require.NoError(t, err)
+		require.NotNil(t, res)
+		require.NotEmpty(t, res.BlockRoot)
+	})
+
+	t.Run("post-Fulu blinded block - builder submission error", func(t *testing.T) {
+		// Set up config with Fulu fork at epoch 5
+		params.SetupTestConfigCleanup(t)
+		cfg := params.BeaconConfig().Copy()
+		cfg.FuluForkEpoch = 5
+		params.OverrideBeaconConfig(cfg)
+
+		mockBuilder := &builderTest.MockBuilderService{
+			HasConfigured:                 true,
+			Cfg:                           &builderTest.Config{BeaconDB: db},
+			ErrSubmitBlindedBlockPostFulu: errors.New("post-Fulu builder submission failed"),
+		}
+
+		c := &mock.ChainService{State: beaconState, Root: parentRoot[:]}
+		proposerServer := &Server{
+			ChainStartFetcher: &mockExecution.Chain{},
+			Eth1InfoFetcher:   &mockExecution.Chain{},
+			Eth1BlockFetcher:  &mockExecution.Chain{},
+			BlockReceiver:     c,
+			BlobReceiver:      c,
+			HeadFetcher:       c,
+			BlockNotifier:     c.BlockNotifier(),
+			OperationNotifier: c.OperationNotifier(),
+			StateGen:          stategen.New(db, doublylinkedtree.New()),
+			TimeFetcher:       c,
+			SyncChecker:       &mockSync.Sync{IsSyncing: false},
+			BeaconDB:          db,
+			BlockBuilder:      mockBuilder,
+			P2P:               &mockp2p.MockBroadcaster{},
+		}
+
+		// Create a blinded block at slot 160 (epoch 5)
+		blindedBlock := util.NewBlindedBeaconBlockDeneb()
+		blindedBlock.Message.Slot = 160
+		blindedBlock.Message.ProposerIndex = 0
+		blindedBlock.Message.ParentRoot = parentRoot[:]
+		blindedBlock.Message.StateRoot = make([]byte, 32)
+
+		req := &ethpb.GenericSignedBeaconBlock{
+			Block: &ethpb.GenericSignedBeaconBlock_BlindedDeneb{BlindedDeneb: blindedBlock},
+		}
+
+		_, err := proposerServer.ProposeBeaconBlock(ctx, req)
+		require.ErrorContains(t, "Could not submit blinded block post-Fulu", err)
+		require.ErrorContains(t, "post-Fulu builder submission failed", err)
+	})
+
+	t.Run("pre-Fulu blinded block - uses regular handleBlindedBlock path", func(t *testing.T) {
+		// Set up config with Fulu fork at epoch 10 (future)
+		params.SetupTestConfigCleanup(t)
+		cfg := params.BeaconConfig().Copy()
+		cfg.FuluForkEpoch = 10
+		params.OverrideBeaconConfig(cfg)
+
+		mockBuilder := &builderTest.MockBuilderService{
+			HasConfigured: true,
+			Cfg:           &builderTest.Config{BeaconDB: db},
+			PayloadDeneb:  &enginev1.ExecutionPayloadDeneb{},
+			BlobBundle:    &enginev1.BlobsBundle{},
+		}
+
+		c := &mock.ChainService{State: beaconState, Root: parentRoot[:]}
+		proposerServer := &Server{
+			ChainStartFetcher: &mockExecution.Chain{},
+			Eth1InfoFetcher:   &mockExecution.Chain{},
+			Eth1BlockFetcher:  &mockExecution.Chain{},
+			BlockReceiver:     c,
+			BlobReceiver:      c,
+			HeadFetcher:       c,
+			BlockNotifier:     c.BlockNotifier(),
+			OperationNotifier: c.OperationNotifier(),
+			StateGen:          stategen.New(db, doublylinkedtree.New()),
+			TimeFetcher:       c,
+			SyncChecker:       &mockSync.Sync{IsSyncing: false},
+			BeaconDB:          db,
+			BlockBuilder:      mockBuilder,
+			P2P:               &mockp2p.MockBroadcaster{},
+		}
+
+		// Create a blinded block at slot 160 (epoch 5, which is < FuluForkEpoch=10)
+		blindedBlock := util.NewBlindedBeaconBlockDeneb()
+		blindedBlock.Message.Slot = 160
+		blindedBlock.Message.ProposerIndex = 0
+		blindedBlock.Message.ParentRoot = parentRoot[:]
+		blindedBlock.Message.StateRoot = make([]byte, 32)
+
+		req := &ethpb.GenericSignedBeaconBlock{
+			Block: &ethpb.GenericSignedBeaconBlock_BlindedDeneb{BlindedDeneb: blindedBlock},
+		}
+
+		// This should NOT trigger the post-Fulu early return path, but use handleBlindedBlock instead
+		res, err := proposerServer.ProposeBeaconBlock(ctx, req)
+		require.NoError(t, err)
+		require.NotNil(t, res)
+		require.NotEmpty(t, res.BlockRoot)
+	})
+
+	t.Run("boundary test - exactly at Fulu fork epoch", func(t *testing.T) {
+		// Set up config with Fulu fork at epoch 5
+		params.SetupTestConfigCleanup(t)
+		cfg := params.BeaconConfig().Copy()
+		cfg.FuluForkEpoch = 5
+		params.OverrideBeaconConfig(cfg)
+
+		mockBuilder := &builderTest.MockBuilderService{
+			HasConfigured:                 true,
+			Cfg:                           &builderTest.Config{BeaconDB: db},
+			ErrSubmitBlindedBlockPostFulu: nil,
+		}
+
+		c := &mock.ChainService{State: beaconState, Root: parentRoot[:]}
+		proposerServer := &Server{
+			ChainStartFetcher: &mockExecution.Chain{},
+			Eth1InfoFetcher:   &mockExecution.Chain{},
+			Eth1BlockFetcher:  &mockExecution.Chain{},
+			BlockReceiver:     c,
+			BlobReceiver:      c,
+			HeadFetcher:       c,
+			BlockNotifier:     c.BlockNotifier(),
+			OperationNotifier: c.OperationNotifier(),
+			StateGen:          stategen.New(db, doublylinkedtree.New()),
+			TimeFetcher:       c,
+			SyncChecker:       &mockSync.Sync{IsSyncing: false},
+			BeaconDB:          db,
+			BlockBuilder:      mockBuilder,
+			P2P:               &mockp2p.MockBroadcaster{},
+		}
+
+		// Create a blinded block at slot 160 (exactly epoch 5)
+		blindedBlock := util.NewBlindedBeaconBlockDeneb()
+		blindedBlock.Message.Slot = 160 // 160/32 = 5 (exactly at FuluForkEpoch)
+		blindedBlock.Message.ProposerIndex = 0
+		blindedBlock.Message.ParentRoot = parentRoot[:]
+		blindedBlock.Message.StateRoot = make([]byte, 32)
+
+		req := &ethpb.GenericSignedBeaconBlock{
+			Block: &ethpb.GenericSignedBeaconBlock_BlindedDeneb{BlindedDeneb: blindedBlock},
+		}
+
+		// Should trigger post-Fulu path since epoch 5 >= FuluForkEpoch (5)
+		res, err := proposerServer.ProposeBeaconBlock(ctx, req)
+		require.NoError(t, err)
+		require.NotNil(t, res)
+		require.NotEmpty(t, res.BlockRoot)
+	})
+
+	t.Run("unblinded block - not affected by post-Fulu condition", func(t *testing.T) {
+		// Set up config with Fulu fork at epoch 5
+		params.SetupTestConfigCleanup(t)
+		cfg := params.BeaconConfig().Copy()
+		cfg.FuluForkEpoch = 5
+		params.OverrideBeaconConfig(cfg)
+
+		c := &mock.ChainService{State: beaconState, Root: parentRoot[:]}
+		proposerServer := &Server{
+			ChainStartFetcher: &mockExecution.Chain{},
+			Eth1InfoFetcher:   &mockExecution.Chain{},
+			Eth1BlockFetcher:  &mockExecution.Chain{},
+			BlockReceiver:     c,
+			BlobReceiver:      c,
+			HeadFetcher:       c,
+			BlockNotifier:     c.BlockNotifier(),
+			OperationNotifier: c.OperationNotifier(),
+			StateGen:          stategen.New(db, doublylinkedtree.New()),
+			TimeFetcher:       c,
+			SyncChecker:       &mockSync.Sync{IsSyncing: false},
+			BeaconDB:          db,
+			P2P:               &mockp2p.MockBroadcaster{},
+		}
+
+		// Create an unblinded block at slot 160 (epoch 5)
+		unblindeBlock := util.NewBeaconBlockDeneb()
+		unblindeBlock.Block.Slot = 160
+		unblindeBlock.Block.ProposerIndex = 0
+		unblindeBlock.Block.ParentRoot = parentRoot[:]
+		unblindeBlock.Block.StateRoot = make([]byte, 32)
+
+		req := &ethpb.GenericSignedBeaconBlock{
+			Block: &ethpb.GenericSignedBeaconBlock_Deneb{
+				Deneb: &ethpb.SignedBeaconBlockContentsDeneb{
+					Block: unblindeBlock,
+				},
+			},
+		}
+
+		// Unblinded blocks should not trigger post-Fulu condition, even at epoch >= FuluForkEpoch
+		res, err := proposerServer.ProposeBeaconBlock(ctx, req)
+		require.NoError(t, err)
+		require.NotNil(t, res)
+		require.NotEmpty(t, res.BlockRoot)
+	})
+}

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

@@ -4,6 +4,7 @@
 package validator
 
 import (
+	"bytes"
 	"context"
 	"time"
 
@@ -28,10 +29,11 @@ import (
 	"github.com/OffchainLabs/prysm/v6/beacon-chain/state/stategen"
 	"github.com/OffchainLabs/prysm/v6/beacon-chain/sync"
 	"github.com/OffchainLabs/prysm/v6/config/params"
+	"github.com/OffchainLabs/prysm/v6/consensus-types/primitives"
 	"github.com/OffchainLabs/prysm/v6/encoding/bytesutil"
-	"github.com/OffchainLabs/prysm/v6/network/forks"
+	"github.com/OffchainLabs/prysm/v6/genesis"
 	ethpb "github.com/OffchainLabs/prysm/v6/proto/prysm/v1alpha1"
-	"github.com/OffchainLabs/prysm/v6/runtime/version"
+	"github.com/OffchainLabs/prysm/v6/time/slots"
 	"google.golang.org/grpc/codes"
 	"google.golang.org/grpc/status"
 	"google.golang.org/protobuf/types/known/emptypb"
@@ -155,32 +157,31 @@ func (vs *Server) ValidatorIndex(ctx context.Context, req *ethpb.ValidatorIndexR
 //
 // DomainData fetches the current domain version information from the beacon state.
 func (vs *Server) DomainData(ctx context.Context, request *ethpb.DomainRequest) (*ethpb.DomainResponse, error) {
-	fork, err := forks.Fork(request.Epoch)
-	if err != nil {
-		return nil, err
-	}
-	headGenesisValidatorsRoot := vs.HeadFetcher.HeadGenesisValidatorsRoot()
-	isExitDomain := [4]byte(request.Domain) == params.BeaconConfig().DomainVoluntaryExit
-	if isExitDomain {
+	epoch := request.Epoch
+	rd := bytesutil.ToBytes4(request.Domain)
+	if bytes.Equal(request.Domain, params.BeaconConfig().DomainVoluntaryExit[:]) {
 		hs, err := vs.HeadFetcher.HeadStateReadOnly(ctx)
 		if err != nil {
 			return nil, err
 		}
-		if hs.Version() >= version.Deneb {
-			fork = &ethpb.Fork{
+		if slots.ToEpoch(hs.Slot()) >= params.BeaconConfig().DenebForkEpoch {
+			return computeDomainData(rd, epoch, &ethpb.Fork{
 				PreviousVersion: params.BeaconConfig().CapellaForkVersion,
 				CurrentVersion:  params.BeaconConfig().CapellaForkVersion,
 				Epoch:           params.BeaconConfig().CapellaForkEpoch,
-			}
+			})
 		}
 	}
-	dv, err := signing.Domain(fork, request.Epoch, bytesutil.ToBytes4(request.Domain), headGenesisValidatorsRoot[:])
+	return computeDomainData(rd, epoch, params.ForkFromConfig(params.BeaconConfig(), epoch))
+}
+
+func computeDomainData(domain [4]byte, epoch primitives.Epoch, fork *ethpb.Fork) (*ethpb.DomainResponse, error) {
+	gvr := genesis.ValidatorsRoot()
+	domainData, err := signing.Domain(fork, epoch, domain, gvr[:])
 	if err != nil {
 		return nil, err
 	}
-	return &ethpb.DomainResponse{
-		SignatureDomain: dv,
-	}, nil
+	return &ethpb.DomainResponse{SignatureDomain: domainData}, 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.

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

@@ -2,6 +2,7 @@ package validator
 
 import (
 	"context"
+	"fmt"
 	"sync"
 	"testing"
 	"time"
@@ -17,11 +18,13 @@ import (
 	"github.com/OffchainLabs/prysm/v6/consensus-types/primitives"
 	"github.com/OffchainLabs/prysm/v6/crypto/bls"
 	"github.com/OffchainLabs/prysm/v6/encoding/bytesutil"
+	"github.com/OffchainLabs/prysm/v6/genesis"
 	ethpb "github.com/OffchainLabs/prysm/v6/proto/prysm/v1alpha1"
 	"github.com/OffchainLabs/prysm/v6/testing/assert"
 	"github.com/OffchainLabs/prysm/v6/testing/mock"
 	"github.com/OffchainLabs/prysm/v6/testing/require"
 	"github.com/OffchainLabs/prysm/v6/testing/util"
+	"github.com/ethereum/go-ethereum/common/hexutil"
 	logTest "github.com/sirupsen/logrus/hooks/test"
 	"go.uber.org/mock/gomock"
 	"google.golang.org/grpc/codes"
@@ -317,55 +320,63 @@ func TestWaitForChainStart_NotStartedThenLogFired(t *testing.T) {
 	require.LogsContain(t, hook, "Sending genesis time")
 }
 
-func TestServer_DomainData_Exits(t *testing.T) {
-	params.SetupTestConfigCleanup(t)
-	cfg := params.BeaconConfig().Copy()
-	cfg.ForkVersionSchedule = map[[4]byte]primitives.Epoch{
-		[4]byte(cfg.GenesisForkVersion):   primitives.Epoch(0),
-		[4]byte(cfg.AltairForkVersion):    primitives.Epoch(5),
-		[4]byte(cfg.BellatrixForkVersion): primitives.Epoch(10),
-		[4]byte(cfg.CapellaForkVersion):   primitives.Epoch(15),
-		[4]byte(cfg.DenebForkVersion):     primitives.Epoch(20),
-	}
-	params.OverrideBeaconConfig(cfg)
-	beaconState := &ethpb.BeaconStateBellatrix{
-		Slot: 4000,
-	}
-	block := util.NewBeaconBlock()
-	genesisRoot, err := block.Block.HashTreeRoot()
-	require.NoError(t, err, "Could not get signing root")
-	s, err := state_native.InitializeFromProtoUnsafeBellatrix(beaconState)
+func testSigDomainForSlot(t *testing.T, domain [4]byte, chsrv *mockChain.ChainService, epoch primitives.Epoch) *ethpb.DomainResponse {
+	cfg := params.BeaconConfig()
+	gvr := genesis.ValidatorsRoot()
+	s, err := state_native.InitializeFromProtoUnsafeDeneb(&ethpb.BeaconStateDeneb{
+		Slot:                  primitives.Slot(epoch) * cfg.SlotsPerEpoch,
+		GenesisValidatorsRoot: gvr[:],
+	})
 	require.NoError(t, err)
+	chsrv.State = s
 	vs := &Server{
 		Ctx:               t.Context(),
 		ChainStartFetcher: &mockExecution.Chain{},
-		HeadFetcher:       &mockChain.ChainService{State: s, Root: genesisRoot[:]},
+		HeadFetcher:       chsrv,
 	}
-
-	reqDomain, err := vs.DomainData(t.Context(), &ethpb.DomainRequest{
-		Epoch:  100,
-		Domain: params.BeaconConfig().DomainDeposit[:],
-	})
-	assert.NoError(t, err)
-	wantedDomain, err := signing.ComputeDomain(params.BeaconConfig().DomainDeposit, params.BeaconConfig().DenebForkVersion, make([]byte, 32))
-	assert.NoError(t, err)
-	assert.DeepEqual(t, reqDomain.SignatureDomain, wantedDomain)
-
-	beaconStateNew := &ethpb.BeaconStateDeneb{
-		Slot: 4000,
-	}
-	s, err = state_native.InitializeFromProtoUnsafeDeneb(beaconStateNew)
-	require.NoError(t, err)
-	vs.HeadFetcher = &mockChain.ChainService{State: s, Root: genesisRoot[:]}
-
-	reqDomain, err = vs.DomainData(t.Context(), &ethpb.DomainRequest{
-		Epoch:  100,
-		Domain: params.BeaconConfig().DomainVoluntaryExit[:],
+	domainResp, err := vs.DomainData(t.Context(), &ethpb.DomainRequest{
+		Epoch:  epoch,
+		Domain: domain[:],
 	})
 	require.NoError(t, err)
-
-	wantedDomain, err = signing.ComputeDomain(params.BeaconConfig().DomainVoluntaryExit, params.BeaconConfig().CapellaForkVersion, make([]byte, 32))
-	require.NoError(t, err)
-
-	assert.DeepEqual(t, reqDomain.SignatureDomain, wantedDomain)
+	return domainResp
+}
+
+func requireSigningEqual(t *testing.T, name string, domain [4]byte, req, want primitives.Epoch, chsrv *mockChain.ChainService) {
+	t.Run(fmt.Sprintf("%s_%#x", name, domain), func(t *testing.T) {
+		gvr := genesis.ValidatorsRoot()
+		resp := testSigDomainForSlot(t, domain, chsrv, req)
+		entry := params.GetNetworkScheduleEntry(want)
+		wanted, err := signing.ComputeDomain(domain, entry.ForkVersion[:], gvr[:])
+		assert.NoError(t, err)
+		assert.Equal(t, hexutil.Encode(wanted), hexutil.Encode(resp.SignatureDomain))
+	})
+}
+
+func TestServer_DomainData_Exits(t *testing.T) {
+	// This test makes 2 sets of assertions:
+	// - the deposit domain is always computed wrt the fork version at the given epoch
+	// - the exit domain is the same until deneb, at which point it is always computed wrt the capella fork version
+	params.SetActiveTestCleanup(t, params.MainnetConfig())
+	params.BeaconConfig().InitializeForkSchedule()
+	cfg := params.BeaconConfig()
+
+	block := util.NewBeaconBlock()
+	genesisRoot, err := block.Block.HashTreeRoot()
+	require.NoError(t, err, "Could not get signing root")
+	chsrv := &mockChain.ChainService{Root: genesisRoot[:]}
+	last := params.LastForkEpoch()
+	requireSigningEqual(t, "genesis deposit", cfg.DomainDeposit, cfg.GenesisEpoch, cfg.GenesisEpoch, chsrv)
+	requireSigningEqual(t, "altair deposit", cfg.DomainDeposit, cfg.AltairForkEpoch, cfg.AltairForkEpoch, chsrv)
+	requireSigningEqual(t, "bellatrix deposit", cfg.DomainDeposit, cfg.BellatrixForkEpoch, cfg.BellatrixForkEpoch, chsrv)
+	requireSigningEqual(t, "capella deposit", cfg.DomainDeposit, cfg.CapellaForkEpoch, cfg.CapellaForkEpoch, chsrv)
+	requireSigningEqual(t, "deneb deposit", cfg.DomainDeposit, cfg.DenebForkEpoch, cfg.DenebForkEpoch, chsrv)
+	requireSigningEqual(t, "last epoch deposit", cfg.DomainDeposit, last, last, chsrv)
+
+	requireSigningEqual(t, "genesis exit", cfg.DomainVoluntaryExit, cfg.GenesisEpoch, cfg.GenesisEpoch, chsrv)
+	requireSigningEqual(t, "altair exit", cfg.DomainVoluntaryExit, cfg.AltairForkEpoch, cfg.AltairForkEpoch, chsrv)
+	requireSigningEqual(t, "bellatrix exit", cfg.DomainVoluntaryExit, cfg.BellatrixForkEpoch, cfg.BellatrixForkEpoch, chsrv)
+	requireSigningEqual(t, "capella exit", cfg.DomainVoluntaryExit, cfg.CapellaForkEpoch, cfg.CapellaForkEpoch, chsrv)
+	requireSigningEqual(t, "deneb exit", cfg.DomainVoluntaryExit, cfg.DenebForkEpoch, cfg.CapellaForkEpoch, chsrv)
+	requireSigningEqual(t, "last epoch exit", cfg.DomainVoluntaryExit, last, cfg.CapellaForkEpoch, chsrv)
 }

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

@@ -37,7 +37,7 @@ func TestUnblinder_UnblindBlobSidecars_InvalidBundle(t *testing.T) {
 func TestUnblindBlobsSidecars_WithBlobsBundler(t *testing.T) {
 	// Test that the function accepts BlobsBundler interface
 	// This test focuses on the interface change rather than full integration
-	
+
 	t.Run("Interface compatibility with BlobsBundle", func(t *testing.T) {
 		// Create a simple pre-Deneb block that will return nil (no processing needed)
 		wBlock, err := consensusblocks.NewSignedBeaconBlock(&ethpb.SignedBeaconBlockCapella{
@@ -87,7 +87,7 @@ func TestUnblindBlobsSidecars_WithBlobsBundler(t *testing.T) {
 	t.Run("Function signature accepts BlobsBundler interface", func(t *testing.T) {
 		// This test verifies that the function signature has been updated to accept BlobsBundler
 		// We test this by verifying the code compiles with both types
-		
+
 		// Create a simple pre-Deneb block for the interface test
 		wBlock, err := consensusblocks.NewSignedBeaconBlock(&ethpb.SignedBeaconBlockCapella{
 			Block: &ethpb.BeaconBlockCapella{
@@ -106,7 +106,7 @@ func TestUnblindBlobsSidecars_WithBlobsBundler(t *testing.T) {
 		_, err = unblindBlobsSidecars(wBlock, regularBundle)
 		require.NoError(t, err)
 
-		// Verify function accepts BlobsBundleV2 through the interface  
+		// Verify function accepts BlobsBundleV2 through the interface
 		var bundleV2 enginev1.BlobsBundler = &enginev1.BlobsBundleV2{
 			KzgCommitments: [][]byte{make([]byte, 48)},
 			Proofs:         [][]byte{make([]byte, 48)},

beacon-chain/rpc/service.go

@@ -120,6 +120,7 @@ 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 +197,7 @@ 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{

beacon-chain/rpc/testutil/mock_stater.go

@@ -15,10 +15,14 @@ type MockStater struct {
 	BeaconStateRoot   []byte
 	StatesBySlot      map[primitives.Slot]state.BeaconState
 	StatesByRoot      map[[32]byte]state.BeaconState
+	CustomError       error
 }
 
 // State --
 func (m *MockStater) State(ctx context.Context, id []byte) (state.BeaconState, error) {
+	if m.CustomError != nil {
+		return nil, m.CustomError
+	}
 	if m.StateProviderFunc != nil {
 		return m.StateProviderFunc(ctx, id)
 	}