add nil checks

* Code cleanup in `blockchain` module

* revert comment fix

* remove test

* forkchoice test fix

Co-authored-by: prylabs-bulldozer[bot] <58059840+prylabs-bulldozer[bot]@users.noreply.github.com>

.github/workflows/go.yml

@@ -67,13 +67,7 @@ jobs:
           args: --print-issued-lines --sort-results --no-config --timeout=10m --disable-all -E deadcode  -E errcheck -E gosimple --skip-files=validator/web/site_data.go --skip-dirs=proto --go=1.17
           version: v1.45.2
           skip-go-installation: true
-      - name: Horusec Downloader 
-        run:  curl -fsSL https://raw.githubusercontent.com/ZupIT/horusec/main/deployments/scripts/install.sh | bash -s latest
-     
-      - name: Horusec Security Scanner 
-        run:  horusec start -p="./" -e="true" -i="**/crypto/bls/herumi/**, **/**/*_test.go, **/third_party/afl/**, **/crypto/keystore/key.go"
-    
-  
+
   build:
     name: Build
     runs-on: ubuntu-latest

.github/workflows/horusec.yaml

@@ -0,0 +1,22 @@
+name: Horusec Security Scan
+
+on:
+  schedule:
+    # Runs cron at 16.00 UTC on
+    - cron: '0 0 * * SUN'
+
+jobs:
+  Horusec_Scan:
+    name: horusec-Scan
+    runs-on: ubuntu-latest
+    if: github.ref == 'refs/heads/develop'
+    steps:
+    - name: Check out code
+      uses: actions/checkout@v2
+      with: # Required when commit authors is enabled
+        fetch-depth: 0
+        
+    - name: Running Security Scan
+      run: |
+        curl -fsSL https://raw.githubusercontent.com/ZupIT/horusec/main/deployments/scripts/install.sh | bash -s latest
+        horusec start -t="10000" -p="./" -e="true" -i="**/crypto/bls/herumi/**, **/**/*_test.go, **/third_party/afl/**, **/crypto/keystore/key.go"

BUILD.bazel

@@ -115,18 +115,19 @@ nogo(
         "@org_golang_x_tools//go/analysis/passes/assign:go_default_library",
         "@org_golang_x_tools//go/analysis/passes/inspect:go_default_library",
         "@org_golang_x_tools//go/analysis/passes/asmdecl:go_default_library",
-        "//tools/analyzers/maligned:go_default_library",
+        "//tools/analyzers/comparesame:go_default_library",
         "//tools/analyzers/cryptorand:go_default_library",
         "//tools/analyzers/errcheck:go_default_library",
         "//tools/analyzers/featureconfig:go_default_library",
-        "//tools/analyzers/comparesame:go_default_library",
-        "//tools/analyzers/shadowpredecl:go_default_library",
-        "//tools/analyzers/nop:go_default_library",
-        "//tools/analyzers/slicedirect:go_default_library",
-        "//tools/analyzers/interfacechecker:go_default_library",
+        "//tools/analyzers/gocognit:go_default_library",
         "//tools/analyzers/ineffassign:go_default_library",
+        "//tools/analyzers/interfacechecker:go_default_library",
+        "//tools/analyzers/maligned:go_default_library",
+        "//tools/analyzers/nop:go_default_library",
         "//tools/analyzers/properpermissions:go_default_library",
         "//tools/analyzers/recursivelock:go_default_library",
+        "//tools/analyzers/shadowpredecl:go_default_library",
+        "//tools/analyzers/slicedirect:go_default_library",
         "//tools/analyzers/uintcast:go_default_library",
     ] + select({
         # nogo checks that fail with coverage enabled.

WORKSPACE

@@ -176,7 +176,7 @@ load("@io_bazel_rules_go//go:deps.bzl", "go_register_toolchains", "go_rules_depe
 go_rules_dependencies()
 
 go_register_toolchains(
-    go_version = "1.17.6",
+    go_version = "1.17.9",
     nogo = "@//:nogo",
 )
 

api/client/beacon/client.go

@@ -6,7 +6,6 @@ import (
 	"encoding/json"
 	"fmt"
 	"io"
-	"io/ioutil"
 	"net"
 	"net/http"
 	"net/url"
@@ -369,7 +368,7 @@ type WeakSubjectivityData struct {
 }
 
 func non200Err(response *http.Response) error {
-	bodyBytes, err := ioutil.ReadAll(response.Body)
+	bodyBytes, err := io.ReadAll(response.Body)
 	var body string
 	if err != nil {
 		body = "(Unable to read response body.)"

api/gateway/apimiddleware/process_field.go

@@ -3,6 +3,7 @@ package apimiddleware
 import (
 	"encoding/base64"
 	"fmt"
+	"math/big"
 	"reflect"
 	"strconv"
 	"strings"
@@ -73,6 +74,10 @@ func processField(s interface{}, processors []fieldProcessor) error {
 }
 
 func hexToBase64Processor(v reflect.Value) error {
+	if v.String() == "0x" {
+		v.SetString("")
+		return nil
+	}
 	b, err := bytesutil.FromHexString(v.String())
 	if err != nil {
 		return err
@@ -83,6 +88,8 @@ func hexToBase64Processor(v reflect.Value) error {
 
 func base64ToHexProcessor(v reflect.Value) error {
 	if v.String() == "" {
+		// Empty hex values are represented as "0x".
+		v.SetString("0x")
 		return nil
 	}
 	b, err := base64.StdEncoding.DecodeString(v.String())
@@ -93,6 +100,55 @@ func base64ToHexProcessor(v reflect.Value) error {
 	return nil
 }
 
+func base64ToUint256Processor(v reflect.Value) error {
+	if v.String() == "" {
+		return nil
+	}
+	littleEndian, err := base64.StdEncoding.DecodeString(v.String())
+	if err != nil {
+		return err
+	}
+	if len(littleEndian) != 32 {
+		return errors.New("invalid length for Uint256")
+	}
+
+	// Integers are stored as little-endian, but
+	// big.Int expects big-endian. So we need to reverse
+	// the byte order before decoding.
+	var bigEndian [32]byte
+	for i := 0; i < len(littleEndian); i++ {
+		bigEndian[i] = littleEndian[len(littleEndian)-1-i]
+	}
+	var uint256 big.Int
+	uint256.SetBytes(bigEndian[:])
+	v.SetString(uint256.String())
+	return nil
+}
+
+func uint256ToBase64Processor(v reflect.Value) error {
+	if v.String() == "" {
+		return nil
+	}
+	uint256, ok := new(big.Int).SetString(v.String(), 10)
+	if !ok {
+		return fmt.Errorf("could not parse Uint256")
+	}
+	bigEndian := uint256.Bytes()
+	if len(bigEndian) > 32 {
+		return fmt.Errorf("number too big for Uint256")
+	}
+
+	// Integers are stored as little-endian, but
+	// big.Int gives big-endian. So we need to reverse
+	// the byte order before encoding.
+	var littleEndian [32]byte
+	for i := 0; i < len(bigEndian); i++ {
+		littleEndian[i] = bigEndian[len(bigEndian)-1-i]
+	}
+	v.SetString(base64.StdEncoding.EncodeToString(littleEndian[:]))
+	return nil
+}
+
 func enumToLowercaseProcessor(v reflect.Value) error {
 	v.SetString(strings.ToLower(v.String()))
 	return nil

api/gateway/apimiddleware/process_request.go

@@ -4,7 +4,6 @@ import (
 	"bytes"
 	"encoding/json"
 	"io"
-	"io/ioutil"
 	"net"
 	"net/http"
 	"strconv"
@@ -38,6 +37,10 @@ func ProcessRequestContainerFields(requestContainer interface{}) ErrorJson {
 			tag: "hex",
 			f:   hexToBase64Processor,
 		},
+		{
+			tag: "uint256",
+			f:   uint256ToBase64Processor,
+		},
 	}); err != nil {
 		return InternalServerErrorWithMessage(err, "could not process request data")
 	}
@@ -52,7 +55,7 @@ func SetRequestBodyToRequestContainer(requestContainer interface{}, req *http.Re
 		return InternalServerErrorWithMessage(err, "could not marshal request")
 	}
 	// Set the body to the new JSON.
-	req.Body = ioutil.NopCloser(bytes.NewReader(j))
+	req.Body = io.NopCloser(bytes.NewReader(j))
 	req.Header.Set("Content-Length", strconv.Itoa(len(j)))
 	req.ContentLength = int64(len(j))
 	return nil
@@ -93,7 +96,7 @@ func (m *ApiProxyMiddleware) ProxyRequest(req *http.Request) (*http.Response, Er
 
 // ReadGrpcResponseBody reads the body from the grpc-gateway's response.
 func ReadGrpcResponseBody(r io.Reader) ([]byte, ErrorJson) {
-	body, err := ioutil.ReadAll(r)
+	body, err := io.ReadAll(r)
 	if err != nil {
 		return nil, InternalServerErrorWithMessage(err, "could not read response body")
 	}
@@ -154,6 +157,10 @@ func ProcessMiddlewareResponseFields(responseContainer interface{}) ErrorJson {
 			tag: "time",
 			f:   timeToUnixProcessor,
 		},
+		{
+			tag: "uint256",
+			f:   base64ToUint256Processor,
+		},
 	}); err != nil {
 		return InternalServerErrorWithMessage(err, "could not process response data")
 	}
@@ -195,7 +202,7 @@ func WriteMiddlewareResponseHeadersAndBody(grpcResp *http.Response, responseJson
 		} else {
 			w.WriteHeader(grpcResp.StatusCode)
 		}
-		if _, err := io.Copy(w, ioutil.NopCloser(bytes.NewReader(responseJson))); err != nil {
+		if _, err := io.Copy(w, io.NopCloser(bytes.NewReader(responseJson))); err != nil {
 			return InternalServerErrorWithMessage(err, "could not write response message")
 		}
 	} else {
@@ -249,7 +256,7 @@ func WriteError(w http.ResponseWriter, errJson ErrorJson, responseHeader http.He
 	w.Header().Set("Content-Length", strconv.Itoa(len(j)))
 	w.Header().Set("Content-Type", "application/json")
 	w.WriteHeader(errJson.StatusCode())
-	if _, err := io.Copy(w, ioutil.NopCloser(bytes.NewReader(j))); err != nil {
+	if _, err := io.Copy(w, io.NopCloser(bytes.NewReader(j))); err != nil {
 		log.WithError(err).Error("Could not write error message")
 	}
 }

api/gateway/apimiddleware/process_request_test.go

@@ -15,30 +15,40 @@ import (
 )
 
 type testRequestContainer struct {
-	TestString    string
-	TestHexString string `hex:"true"`
+	TestString         string
+	TestHexString      string `hex:"true"`
+	TestEmptyHexString string `hex:"true"`
+	TestUint256String  string `uint256:"true"`
 }
 
 func defaultRequestContainer() *testRequestContainer {
 	return &testRequestContainer{
-		TestString:    "test string",
-		TestHexString: "0x666F6F", // hex encoding of "foo"
+		TestString:         "test string",
+		TestHexString:      "0x666F6F", // hex encoding of "foo"
+		TestEmptyHexString: "0x",
+		TestUint256String:  "4196",
 	}
 }
 
 type testResponseContainer struct {
-	TestString string
-	TestHex    string `hex:"true"`
-	TestEnum   string `enum:"true"`
-	TestTime   string `time:"true"`
+	TestString   string
+	TestHex      string `hex:"true"`
+	TestEmptyHex string `hex:"true"`
+	TestUint256  string `uint256:"true"`
+	TestEnum     string `enum:"true"`
+	TestTime     string `time:"true"`
 }
 
 func defaultResponseContainer() *testResponseContainer {
 	return &testResponseContainer{
-		TestString: "test string",
-		TestHex:    "Zm9v", // base64 encoding of "foo"
-		TestEnum:   "Test Enum",
-		TestTime:   "2006-01-02T15:04:05Z",
+		TestString:   "test string",
+		TestHex:      "Zm9v", // base64 encoding of "foo"
+		TestEmptyHex: "",
+		TestEnum:     "Test Enum",
+		TestTime:     "2006-01-02T15:04:05Z",
+
+		// base64 encoding of 4196 in little-endian
+		TestUint256: "ZBAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA=",
 	}
 }
 
@@ -106,6 +116,8 @@ func TestProcessRequestContainerFields(t *testing.T) {
 		errJson := ProcessRequestContainerFields(container)
 		require.Equal(t, true, errJson == nil)
 		assert.Equal(t, "Zm9v", container.TestHexString)
+		assert.Equal(t, "", container.TestEmptyHexString)
+		assert.Equal(t, "ZBAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA=", container.TestUint256String)
 	})
 
 	t.Run("error", func(t *testing.T) {
@@ -128,8 +140,8 @@ func TestSetRequestBodyToRequestContainer(t *testing.T) {
 	contentLengthHeader, ok := request.Header["Content-Length"]
 	require.Equal(t, true, ok)
 	require.Equal(t, 1, len(contentLengthHeader), "wrong number of header values")
-	assert.Equal(t, "55", contentLengthHeader[0])
-	assert.Equal(t, int64(55), request.ContentLength)
+	assert.Equal(t, "108", contentLengthHeader[0])
+	assert.Equal(t, int64(108), request.ContentLength)
 }
 
 func TestPrepareRequestForProxying(t *testing.T) {
@@ -234,6 +246,8 @@ func TestProcessMiddlewareResponseFields(t *testing.T) {
 		errJson := ProcessMiddlewareResponseFields(container)
 		require.Equal(t, true, errJson == nil)
 		assert.Equal(t, "0x666f6f", container.TestHex)
+		assert.Equal(t, "0x", container.TestEmptyHex)
+		assert.Equal(t, "4196", container.TestUint256)
 		assert.Equal(t, "test enum", container.TestEnum)
 		assert.Equal(t, "1136214245", container.TestTime)
 	})
@@ -278,7 +292,7 @@ func TestWriteMiddlewareResponseHeadersAndBody(t *testing.T) {
 		v, ok = writer.Header()["Content-Length"]
 		require.Equal(t, true, ok, "header not found")
 		require.Equal(t, 1, len(v), "wrong number of header values")
-		assert.Equal(t, "102", v[0])
+		assert.Equal(t, "181", v[0])
 		assert.Equal(t, 204, writer.Code)
 		assert.DeepEqual(t, responseJson, writer.Body.Bytes())
 	})

beacon-chain/blockchain/BUILD.bazel

@@ -5,13 +5,13 @@ go_library(
     srcs = [
         "chain_info.go",
         "error.go",
+        "execution_engine.go",
         "head.go",
         "head_sync_committee_info.go",
         "init_sync_process_block.go",
         "log.go",
         "metrics.go",
         "new_slot.go",
-        "optimistic_sync.go",
         "options.go",
         "pow_block.go",
         "process_attestation.go",
@@ -66,6 +66,7 @@ go_library(
         "//config/params:go_default_library",
         "//crypto/bls:go_default_library",
         "//encoding/bytesutil:go_default_library",
+        "//math:go_default_library",
         "//monitoring/tracing:go_default_library",
         "//proto/engine/v1:go_default_library",
         "//proto/eth/v1:go_default_library",
@@ -102,13 +103,13 @@ go_test(
         "blockchain_test.go",
         "chain_info_test.go",
         "checktags_test.go",
+        "execution_engine_test.go",
         "head_sync_committee_info_test.go",
         "head_test.go",
         "init_test.go",
         "log_test.go",
         "metrics_test.go",
         "mock_test.go",
-        "optimistic_sync_test.go",
         "pow_block_test.go",
         "process_attestation_test.go",
         "process_block_test.go",

beacon-chain/blockchain/blockchain_test.go

@@ -1,7 +1,7 @@
 package blockchain
 
 import (
-	"io/ioutil"
+	"io"
 	"testing"
 
 	"github.com/sirupsen/logrus"
@@ -9,7 +9,7 @@ import (
 
 func TestMain(m *testing.M) {
 	logrus.SetLevel(logrus.DebugLevel)
-	logrus.SetOutput(ioutil.Discard)
+	logrus.SetOutput(io.Discard)
 
 	m.Run()
 }

beacon-chain/blockchain/chain_info.go

@@ -50,7 +50,6 @@ type HeadFetcher interface {
 	HeadBlock(ctx context.Context) (block.SignedBeaconBlock, error)
 	HeadState(ctx context.Context) (state.BeaconState, error)
 	HeadValidatorsIndices(ctx context.Context, epoch types.Epoch) ([]types.ValidatorIndex, error)
-	HeadSeed(ctx context.Context, epoch types.Epoch) ([32]byte, error)
 	HeadGenesisValidatorsRoot() [32]byte
 	HeadETH1Data() *ethpb.Eth1Data
 	HeadPublicKeyToValidatorIndex(pubKey [fieldparams.BLSPubkeyLength]byte) (types.ValidatorIndex, bool)
@@ -60,18 +59,17 @@ type HeadFetcher interface {
 	IsOptimisticForRoot(ctx context.Context, root [32]byte) (bool, error)
 	HeadSyncCommitteeFetcher
 	HeadDomainFetcher
-	ForkChoicer() forkchoice.ForkChoicer
 }
 
 // ForkFetcher retrieves the current fork information of the Ethereum beacon chain.
 type ForkFetcher interface {
+	ForkChoicer() forkchoice.ForkChoicer
 	CurrentFork() *ethpb.Fork
 }
 
 // CanonicalFetcher retrieves the current chain's canonical information.
 type CanonicalFetcher interface {
 	IsCanonical(ctx context.Context, blockRoot [32]byte) (bool, error)
-	VerifyBlkDescendant(ctx context.Context, blockRoot [32]byte) error
 }
 
 // FinalizationFetcher defines a common interface for methods in blockchain service which
@@ -80,6 +78,7 @@ type FinalizationFetcher interface {
 	FinalizedCheckpt() *ethpb.Checkpoint
 	CurrentJustifiedCheckpt() *ethpb.Checkpoint
 	PreviousJustifiedCheckpt() *ethpb.Checkpoint
+	VerifyFinalizedBlkDescendant(ctx context.Context, blockRoot [32]byte) error
 }
 
 // FinalizedCheckpt returns the latest finalized checkpoint from chain store.
@@ -205,18 +204,6 @@ func (s *Service) HeadValidatorsIndices(ctx context.Context, epoch types.Epoch)
 	return helpers.ActiveValidatorIndices(ctx, s.headState(ctx), epoch)
 }
 
-// HeadSeed returns the seed from the head view of a given epoch.
-func (s *Service) HeadSeed(ctx context.Context, epoch types.Epoch) ([32]byte, error) {
-	s.headLock.RLock()
-	defer s.headLock.RUnlock()
-
-	if !s.hasHeadState() {
-		return [32]byte{}, nil
-	}
-
-	return helpers.Seed(s.headState(ctx), epoch, params.BeaconConfig().DomainBeaconAttester)
-}
-
 // HeadGenesisValidatorsRoot returns genesis validators root of the head state.
 func (s *Service) HeadGenesisValidatorsRoot() [32]byte {
 	s.headLock.RLock()
@@ -273,13 +260,13 @@ func (s *Service) CurrentFork() *ethpb.Fork {
 
 // IsCanonical returns true if the input block root is part of the canonical chain.
 func (s *Service) IsCanonical(ctx context.Context, blockRoot [32]byte) (bool, error) {
-	// If the block has been finalized, the block will always be part of the canonical chain.
-	if s.cfg.BeaconDB.IsFinalizedBlock(ctx, blockRoot) {
-		return true, nil
+	// If the block has not been finalized, check fork choice store to see if the block is canonical
+	if s.cfg.ForkChoiceStore.HasNode(blockRoot) {
+		return s.cfg.ForkChoiceStore.IsCanonical(blockRoot), nil
 	}
 
-	// If the block has not been finalized, check fork choice store to see if the block is canonical
-	return s.cfg.ForkChoiceStore.IsCanonical(blockRoot), nil
+	// If the block has been finalized, the block will always be part of the canonical chain.
+	return s.cfg.BeaconDB.IsFinalizedBlock(ctx, blockRoot), nil
 }
 
 // ChainHeads returns all possible chain heads (leaves of fork choice tree).

beacon-chain/blockchain/chain_info_test.go

@@ -6,7 +6,6 @@ import (
 	"time"
 
 	types "github.com/prysmaticlabs/eth2-types"
-	"github.com/prysmaticlabs/prysm/beacon-chain/core/helpers"
 	testDB "github.com/prysmaticlabs/prysm/beacon-chain/db/testing"
 	doublylinkedtree "github.com/prysmaticlabs/prysm/beacon-chain/forkchoice/doubly-linked-tree"
 	"github.com/prysmaticlabs/prysm/beacon-chain/forkchoice/protoarray"
@@ -261,23 +260,6 @@ func TestService_HeadValidatorsIndices(t *testing.T) {
 	require.Equal(t, 10, len(indices))
 }
 
-func TestService_HeadSeed(t *testing.T) {
-	s, _ := util.DeterministicGenesisState(t, 1)
-	c := &Service{}
-	seed, err := helpers.Seed(s, 0, params.BeaconConfig().DomainBeaconAttester)
-	require.NoError(t, err)
-
-	c.head = &head{}
-	root, err := c.HeadSeed(context.Background(), 0)
-	require.NoError(t, err)
-	require.Equal(t, [32]byte{}, root)
-
-	c.head = &head{state: s}
-	root, err = c.HeadSeed(context.Background(), 0)
-	require.NoError(t, err)
-	require.DeepEqual(t, seed, root)
-}
-
 func TestService_HeadGenesisValidatorsRoot(t *testing.T) {
 	s, _ := util.DeterministicGenesisState(t, 1)
 	c := &Service{}

beacon-chain/blockchain/execution_engine.go

@@ -24,6 +24,8 @@ import (
 	"go.opencensus.io/trace"
 )
 
+var ErrUndefinedExecutionEngineError = errors.New("received an undefined ee error")
+
 // notifyForkchoiceUpdate signals execution engine the fork choice updates. Execution engine should:
 // 1. Re-organizes the execution payload chain and corresponding state to make head_block_hash the head.
 // 2. Applies finality to the execution state: it irreversibly persists the chain of all execution payloads and corresponding state, up to and including finalized_block_hash.
@@ -83,16 +85,18 @@ func (s *Service) notifyForkchoiceUpdate(ctx context.Context, headState state.Be
 	if err != nil {
 		switch err {
 		case powchain.ErrAcceptedSyncingPayloadStatus:
+			forkchoiceUpdatedOptimisticNodeCount.Inc()
 			log.WithFields(logrus.Fields{
-				"headSlot":      headBlk.Slot(),
-				"headHash":      fmt.Sprintf("%#x", bytesutil.Trunc(headPayload.BlockHash)),
-				"finalizedHash": fmt.Sprintf("%#x", bytesutil.Trunc(finalizedHash)),
+				"headSlot":                  headBlk.Slot(),
+				"headPayloadBlockHash":      fmt.Sprintf("%#x", bytesutil.Trunc(headPayload.BlockHash)),
+				"finalizedPayloadBlockHash": fmt.Sprintf("%#x", bytesutil.Trunc(finalizedHash)),
 			}).Info("Called fork choice updated with optimistic block")
 			return payloadID, nil
 		default:
-			return nil, errors.Wrap(err, "could not notify forkchoice update from execution engine")
+			return nil, errors.WithMessage(ErrUndefinedExecutionEngineError, err.Error())
 		}
 	}
+	forkchoiceUpdatedValidNodeCount.Inc()
 	if err := s.cfg.ForkChoiceStore.SetOptimisticToValid(ctx, headRoot); err != nil {
 		return nil, errors.Wrap(err, "could not set block to valid")
 	}
@@ -106,8 +110,8 @@ func (s *Service) notifyForkchoiceUpdate(ctx context.Context, headState state.Be
 
 // notifyForkchoiceUpdate signals execution engine on a new payload.
 // It returns true if the EL has returned VALID for the block
-func (s *Service) notifyNewPayload(ctx context.Context, preStateVersion, postStateVersion int,
-	preStateHeader, postStateHeader *ethpb.ExecutionPayloadHeader, blk block.SignedBeaconBlock) (bool, error) {
+func (s *Service) notifyNewPayload(ctx context.Context, postStateVersion int,
+	postStateHeader *ethpb.ExecutionPayloadHeader, blk block.SignedBeaconBlock) (bool, error) {
 	ctx, span := trace.StartSpan(ctx, "blockChain.notifyNewPayload")
 	defer span.End()
 
@@ -132,46 +136,34 @@ func (s *Service) notifyNewPayload(ctx context.Context, preStateVersion, postSta
 		return false, errors.Wrap(err, "could not get execution payload")
 	}
 	lastValidHash, err := s.cfg.ExecutionEngineCaller.NewPayload(ctx, payload)
-	if err != nil {
-		switch err {
-		case powchain.ErrAcceptedSyncingPayloadStatus:
-			log.WithFields(logrus.Fields{
-				"slot":      blk.Block().Slot(),
-				"blockHash": fmt.Sprintf("%#x", bytesutil.Trunc(payload.BlockHash)),
-			}).Info("Called new payload with optimistic block")
-			return false, nil
-		case powchain.ErrInvalidPayloadStatus:
-			root, err := blk.Block().HashTreeRoot()
-			if err != nil {
-				return false, err
-			}
-			invalidRoots, err := s.ForkChoicer().SetOptimisticToInvalid(ctx, root, bytesutil.ToBytes32(lastValidHash))
-			if err != nil {
-				return false, err
-			}
-			if err := s.removeInvalidBlockAndState(ctx, invalidRoots); err != nil {
-				return false, err
-			}
-			return false, errors.New("could not validate an INVALID payload from execution engine")
-		default:
-			return false, errors.Wrap(err, "could not validate execution payload from execution engine")
-		}
-	}
-
-	// During the transition event, the transition block should be verified for sanity.
-	if blocks.IsPreBellatrixVersion(preStateVersion) {
-		// Handle case where pre-state is Altair but block contains payload.
-		// To reach here, the block must have contained a valid payload.
-		return true, s.validateMergeBlock(ctx, blk)
-	}
-	atTransition, err := blocks.IsMergeTransitionBlockUsingPreStatePayloadHeader(preStateHeader, body)
-	if err != nil {
-		return true, errors.Wrap(err, "could not check if merge block is terminal")
-	}
-	if !atTransition {
+	switch err {
+	case nil:
+		newPayloadValidNodeCount.Inc()
 		return true, nil
+	case powchain.ErrAcceptedSyncingPayloadStatus:
+		newPayloadOptimisticNodeCount.Inc()
+		log.WithFields(logrus.Fields{
+			"slot":             blk.Block().Slot(),
+			"payloadBlockHash": fmt.Sprintf("%#x", bytesutil.Trunc(payload.BlockHash)),
+		}).Info("Called new payload with optimistic block")
+		return false, nil
+	case powchain.ErrInvalidPayloadStatus:
+		newPayloadInvalidNodeCount.Inc()
+		root, err := blk.Block().HashTreeRoot()
+		if err != nil {
+			return false, err
+		}
+		invalidRoots, err := s.ForkChoicer().SetOptimisticToInvalid(ctx, root, bytesutil.ToBytes32(lastValidHash))
+		if err != nil {
+			return false, err
+		}
+		if err := s.removeInvalidBlockAndState(ctx, invalidRoots); err != nil {
+			return false, err
+		}
+		return false, errors.New("could not validate an INVALID payload from execution engine")
+	default:
+		return false, errors.WithMessage(ErrUndefinedExecutionEngineError, err.Error())
 	}
-	return true, s.validateMergeBlock(ctx, blk)
 }
 
 // optimisticCandidateBlock returns true if this block can be optimistically synced.

beacon-chain/blockchain/execution_engine_test.go

@@ -22,7 +22,6 @@ import (
 	ethpb "github.com/prysmaticlabs/prysm/proto/prysm/v1alpha1"
 	"github.com/prysmaticlabs/prysm/proto/prysm/v1alpha1/block"
 	"github.com/prysmaticlabs/prysm/proto/prysm/v1alpha1/wrapper"
-	"github.com/prysmaticlabs/prysm/runtime/version"
 	"github.com/prysmaticlabs/prysm/testing/assert"
 	"github.com/prysmaticlabs/prysm/testing/require"
 	"github.com/prysmaticlabs/prysm/testing/util"
@@ -159,7 +158,7 @@ func Test_NotifyForkchoiceUpdate(t *testing.T) {
 			}(),
 			newForkchoiceErr: powchain.ErrInvalidPayloadStatus,
 			finalizedRoot:    bellatrixBlkRoot,
-			errString:        "could not notify forkchoice update from execution engine: payload status is INVALID",
+			errString:        ErrUndefinedExecutionEngineError.Error(),
 		},
 	}
 
@@ -229,7 +228,6 @@ func Test_NotifyNewPayload(t *testing.T) {
 
 	tests := []struct {
 		name           string
-		preState       state.BeaconState
 		postState      state.BeaconState
 		isValidPayload bool
 		blk            block.SignedBeaconBlock
@@ -239,26 +237,22 @@ func Test_NotifyNewPayload(t *testing.T) {
 		{
 			name:           "phase 0 post state",
 			postState:      phase0State,
-			preState:       phase0State,
 			isValidPayload: true,
 		},
 		{
 			name:           "altair post state",
 			postState:      altairState,
-			preState:       altairState,
 			isValidPayload: true,
 		},
 		{
 			name:           "nil beacon block",
 			postState:      bellatrixState,
-			preState:       bellatrixState,
 			errString:      "signed beacon block can't be nil",
 			isValidPayload: false,
 		},
 		{
 			name:           "new payload with optimistic block",
 			postState:      bellatrixState,
-			preState:       bellatrixState,
 			blk:            bellatrixBlk,
 			newPayloadErr:  powchain.ErrAcceptedSyncingPayloadStatus,
 			isValidPayload: false,
@@ -266,7 +260,6 @@ func Test_NotifyNewPayload(t *testing.T) {
 		{
 			name:           "new payload with invalid block",
 			postState:      bellatrixState,
-			preState:       bellatrixState,
 			blk:            bellatrixBlk,
 			newPayloadErr:  powchain.ErrInvalidPayloadStatus,
 			errString:      "could not validate an INVALID payload from execution engine",
@@ -275,14 +268,12 @@ func Test_NotifyNewPayload(t *testing.T) {
 		{
 			name:           "altair pre state, altair block",
 			postState:      bellatrixState,
-			preState:       altairState,
 			blk:            altairBlk,
 			isValidPayload: true,
 		},
 		{
 			name:      "altair pre state, happy case",
 			postState: bellatrixState,
-			preState:  altairState,
 			blk: func() block.SignedBeaconBlock {
 				blk := &ethpb.SignedBeaconBlockBellatrix{
 					Block: &ethpb.BeaconBlockBellatrix{
@@ -299,18 +290,9 @@ func Test_NotifyNewPayload(t *testing.T) {
 			}(),
 			isValidPayload: true,
 		},
-		{
-			name:           "could not get merge block",
-			postState:      bellatrixState,
-			preState:       bellatrixState,
-			blk:            bellatrixBlk,
-			errString:      "could not get merge block parent hash and total difficulty",
-			isValidPayload: false,
-		},
 		{
 			name:      "not at merge transition",
 			postState: bellatrixState,
-			preState:  bellatrixState,
 			blk: func() block.SignedBeaconBlock {
 				blk := &ethpb.SignedBeaconBlockBellatrix{
 					Block: &ethpb.BeaconBlockBellatrix{
@@ -334,18 +316,9 @@ func Test_NotifyNewPayload(t *testing.T) {
 			}(),
 			isValidPayload: true,
 		},
-		{
-			name:           "could not get merge block",
-			postState:      bellatrixState,
-			preState:       bellatrixState,
-			blk:            bellatrixBlk,
-			errString:      "could not get merge block parent hash and total difficulty",
-			isValidPayload: false,
-		},
 		{
 			name:      "happy case",
 			postState: bellatrixState,
-			preState:  bellatrixState,
 			blk: func() block.SignedBeaconBlock {
 				blk := &ethpb.SignedBeaconBlockBellatrix{
 					Block: &ethpb.BeaconBlockBellatrix{
@@ -362,6 +335,26 @@ func Test_NotifyNewPayload(t *testing.T) {
 			}(),
 			isValidPayload: true,
 		},
+		{
+			name:      "undefined error from ee",
+			postState: bellatrixState,
+			blk: func() block.SignedBeaconBlock {
+				blk := &ethpb.SignedBeaconBlockBellatrix{
+					Block: &ethpb.BeaconBlockBellatrix{
+						Body: &ethpb.BeaconBlockBodyBellatrix{
+							ExecutionPayload: &v1.ExecutionPayload{
+								ParentHash: bytesutil.PadTo([]byte{'a'}, fieldparams.RootLength),
+							},
+						},
+					},
+				}
+				b, err := wrapper.WrappedSignedBeaconBlock(blk)
+				require.NoError(t, err)
+				return b
+			}(),
+			newPayloadErr: ErrUndefinedExecutionEngineError,
+			errString:     ErrUndefinedExecutionEngineError.Error(),
+		},
 	}
 	for _, tt := range tests {
 		t.Run(tt.name, func(t *testing.T) {
@@ -375,16 +368,11 @@ func Test_NotifyNewPayload(t *testing.T) {
 				TotalDifficulty: "0x1",
 			}
 			service.cfg.ExecutionEngineCaller = e
-			var payload *ethpb.ExecutionPayloadHeader
-			if tt.preState.Version() == version.Bellatrix {
-				payload, err = tt.preState.LatestExecutionPayloadHeader()
-				require.NoError(t, err)
-			}
 			root := [32]byte{'a'}
 			require.NoError(t, service.cfg.ForkChoiceStore.InsertOptimisticBlock(ctx, 0, root, root, params.BeaconConfig().ZeroHash, 0, 0))
 			postVersion, postHeader, err := getStateVersionAndPayload(tt.postState)
 			require.NoError(t, err)
-			isValidPayload, err := service.notifyNewPayload(ctx, tt.preState.Version(), postVersion, payload, postHeader, tt.blk)
+			isValidPayload, err := service.notifyNewPayload(ctx, postVersion, postHeader, tt.blk)
 			if tt.errString != "" {
 				require.ErrorContains(t, tt.errString, err)
 			} else {
@@ -431,11 +419,9 @@ func Test_NotifyNewPayload_SetOptimisticToValid(t *testing.T) {
 		TotalDifficulty: "0x1",
 	}
 	service.cfg.ExecutionEngineCaller = e
-	payload, err := bellatrixState.LatestExecutionPayloadHeader()
-	require.NoError(t, err)
 	postVersion, postHeader, err := getStateVersionAndPayload(bellatrixState)
 	require.NoError(t, err)
-	validated, err := service.notifyNewPayload(ctx, bellatrixState.Version(), postVersion, payload, postHeader, bellatrixBlk)
+	validated, err := service.notifyNewPayload(ctx, postVersion, postHeader, bellatrixBlk)
 	require.NoError(t, err)
 	require.Equal(t, true, validated)
 }

beacon-chain/blockchain/metrics.go

@@ -138,6 +138,26 @@ var (
 		Name: "state_balance_cache_miss",
 		Help: "Count the number of state balance cache hits.",
 	})
+	newPayloadValidNodeCount = promauto.NewCounter(prometheus.CounterOpts{
+		Name: "new_payload_valid_node_count",
+		Help: "Count the number of valid nodes after newPayload EE call",
+	})
+	newPayloadOptimisticNodeCount = promauto.NewCounter(prometheus.CounterOpts{
+		Name: "new_payload_optimistic_node_count",
+		Help: "Count the number of optimistic nodes after newPayload EE call",
+	})
+	newPayloadInvalidNodeCount = promauto.NewCounter(prometheus.CounterOpts{
+		Name: "new_payload_invalid_node_count",
+		Help: "Count the number of invalid nodes after newPayload EE call",
+	})
+	forkchoiceUpdatedValidNodeCount = promauto.NewCounter(prometheus.CounterOpts{
+		Name: "forkchoice_updated_valid_node_count",
+		Help: "Count the number of valid nodes after forkchoiceUpdated EE call",
+	})
+	forkchoiceUpdatedOptimisticNodeCount = promauto.NewCounter(prometheus.CounterOpts{
+		Name: "forkchoice_updated_optimistic_node_count",
+		Help: "Count the number of optimistic nodes after forkchoiceUpdated EE call",
+	})
 )
 
 // reportSlotMetrics reports slot related metrics.

beacon-chain/blockchain/process_block.go

@@ -113,11 +113,15 @@ func (s *Service) onBlock(ctx context.Context, signed block.SignedBeaconBlock, b
 	if err != nil {
 		return err
 	}
-	isValidPayload, err := s.notifyNewPayload(ctx, preStateVersion, postStateVersion, preStateHeader, postStateHeader, signed)
+	isValidPayload, err := s.notifyNewPayload(ctx, postStateVersion, postStateHeader, signed)
 	if err != nil {
 		return errors.Wrap(err, "could not verify new payload")
 	}
-	if !isValidPayload {
+	if isValidPayload {
+		if err := s.validateMergeTransitionBlock(ctx, preStateVersion, preStateHeader, signed); err != nil {
+			return err
+		}
+	} else {
 		candidate, err := s.optimisticCandidateBlock(ctx, b)
 		if err != nil {
 			return errors.Wrap(err, "could not check if block is optimistic candidate")
@@ -127,8 +131,8 @@ func (s *Service) onBlock(ctx context.Context, signed block.SignedBeaconBlock, b
 		}
 	}
 
-	if err := s.savePostStateInfo(ctx, blockRoot, signed, postState, false /* reg sync */); err != nil {
-		return err
+	if err := s.insertBlockAndAttestationsToForkChoiceStore(ctx, signed.Block(), blockRoot, postState); err != nil {
+		return errors.Wrapf(err, "could not insert block %d to fork choice store", signed.Block().Slot())
 	}
 	if isValidPayload {
 		if err := s.cfg.ForkChoiceStore.SetOptimisticToValid(ctx, blockRoot); err != nil {
@@ -148,6 +152,9 @@ func (s *Service) onBlock(ctx context.Context, signed block.SignedBeaconBlock, b
 		return err
 	}
 
+	if err := s.savePostStateInfo(ctx, blockRoot, signed, postState); err != nil {
+		return err
+	}
 	// If slasher is configured, forward the attestations in the block via
 	// an event feed for processing.
 	if features.Get().EnableSlasher {
@@ -403,17 +410,18 @@ func (s *Service) onBlockBatch(ctx context.Context, blks []block.SignedBeaconBlo
 
 	// blocks have been verified, add them to forkchoice and call the engine
 	for i, b := range blks {
-		s.saveInitSyncBlock(blockRoots[i], b)
 		isValidPayload, err := s.notifyNewPayload(ctx,
-			preVersionAndHeaders[i].version,
 			postVersionAndHeaders[i].version,
-			preVersionAndHeaders[i].header,
 			postVersionAndHeaders[i].header, b)
-
 		if err != nil {
 			return nil, nil, err
 		}
-		if !isValidPayload {
+		if isValidPayload {
+			if err := s.validateMergeTransitionBlock(ctx, preVersionAndHeaders[i].version,
+				preVersionAndHeaders[i].header, b); err != nil {
+				return nil, nil, err
+			}
+		} else {
 			candidate, err := s.optimisticCandidateBlock(ctx, b.Block())
 			if err != nil {
 				return nil, nil, errors.Wrap(err, "could not check if block is optimistic candidate")
@@ -431,10 +439,7 @@ func (s *Service) onBlockBatch(ctx context.Context, blks []block.SignedBeaconBlo
 				return nil, nil, errors.Wrap(err, "could not set optimistic block to valid")
 			}
 		}
-
-		if _, err := s.notifyForkchoiceUpdate(ctx, preState, b.Block(), blockRoots[i], bytesutil.ToBytes32(fCheckpoints[i].Root)); err != nil {
-			return nil, nil, err
-		}
+		s.saveInitSyncBlock(blockRoots[i], b)
 	}
 
 	for r, st := range boundaries {
@@ -448,6 +453,10 @@ func (s *Service) onBlockBatch(ctx context.Context, blks []block.SignedBeaconBlo
 	if err := s.cfg.StateGen.SaveState(ctx, lastBR, preState); err != nil {
 		return nil, nil, err
 	}
+	f := fCheckpoints[len(fCheckpoints)-1]
+	if _, err := s.notifyForkchoiceUpdate(ctx, preState, lastB.Block(), lastBR, bytesutil.ToBytes32(f.Root)); err != nil {
+		return nil, nil, err
+	}
 	if err := s.saveHeadNoDB(ctx, lastB, lastBR, preState); err != nil {
 		return nil, nil, err
 	}
@@ -598,20 +607,15 @@ func getBlockPayloadHash(blk block.BeaconBlock) ([32]byte, error) {
 
 // This saves post state info to DB or cache. This also saves post state info to fork choice store.
 // Post state info consists of processed block and state. Do not call this method unless the block and state are verified.
-func (s *Service) savePostStateInfo(ctx context.Context, r [32]byte, b block.SignedBeaconBlock, st state.BeaconState, initSync bool) error {
+func (s *Service) savePostStateInfo(ctx context.Context, r [32]byte, b block.SignedBeaconBlock, st state.BeaconState) error {
 	ctx, span := trace.StartSpan(ctx, "blockChain.savePostStateInfo")
 	defer span.End()
-	if initSync {
-		s.saveInitSyncBlock(r, b)
-	} else if err := s.cfg.BeaconDB.SaveBlock(ctx, b); err != nil {
+	if err := s.cfg.BeaconDB.SaveBlock(ctx, b); err != nil {
 		return errors.Wrapf(err, "could not save block from slot %d", b.Block().Slot())
 	}
 	if err := s.cfg.StateGen.SaveState(ctx, r, st); err != nil {
 		return errors.Wrap(err, "could not save state")
 	}
-	if err := s.insertBlockAndAttestationsToForkChoiceStore(ctx, b.Block(), r, st); err != nil {
-		return errors.Wrapf(err, "could not insert block %d to fork choice store", b.Block().Slot())
-	}
 	return nil
 }
 
@@ -644,3 +648,36 @@ func (s *Service) pruneCanonicalAttsFromPool(ctx context.Context, r [32]byte, b
 	}
 	return nil
 }
+
+// validateMergeTransitionBlock validates the merge transition block.
+func (s *Service) validateMergeTransitionBlock(ctx context.Context, stateVersion int, stateHeader *ethpb.ExecutionPayloadHeader, blk block.SignedBeaconBlock) error {
+	// Skip validation if block is older than Bellatrix.
+	if blocks.IsPreBellatrixVersion(blk.Block().Version()) {
+		return nil
+	}
+
+	// Skip validation if block has an empty payload.
+	payload, err := blk.Block().Body().ExecutionPayload()
+	if err != nil {
+		return err
+	}
+	if blocks.IsEmptyPayload(payload) {
+		return nil
+	}
+
+	// Handle case where pre-state is Altair but block contains payload.
+	// To reach here, the block must have contained a valid payload.
+	if blocks.IsPreBellatrixVersion(stateVersion) {
+		return s.validateMergeBlock(ctx, blk)
+	}
+
+	// Skip validation if the block is not a merge transition block.
+	atTransition, err := blocks.IsMergeTransitionBlockUsingPreStatePayloadHeader(stateHeader, blk.Block().Body())
+	if err != nil {
+		return errors.Wrap(err, "could not check if merge block is terminal")
+	}
+	if !atTransition {
+		return nil
+	}
+	return s.validateMergeBlock(ctx, blk)
+}

beacon-chain/blockchain/process_block_helpers.go

@@ -11,6 +11,7 @@ import (
 	"github.com/prysmaticlabs/prysm/beacon-chain/state"
 	"github.com/prysmaticlabs/prysm/config/params"
 	"github.com/prysmaticlabs/prysm/encoding/bytesutil"
+	mathutil "github.com/prysmaticlabs/prysm/math"
 	"github.com/prysmaticlabs/prysm/monitoring/tracing"
 	ethpb "github.com/prysmaticlabs/prysm/proto/prysm/v1alpha1"
 	"github.com/prysmaticlabs/prysm/proto/prysm/v1alpha1/block"
@@ -69,7 +70,7 @@ func (s *Service) verifyBlkPreState(ctx context.Context, b block.BeaconBlock) er
 		return errors.New("could not reconstruct parent state")
 	}
 
-	if err := s.VerifyBlkDescendant(ctx, bytesutil.ToBytes32(b.ParentRoot())); err != nil {
+	if err := s.VerifyFinalizedBlkDescendant(ctx, bytesutil.ToBytes32(b.ParentRoot())); err != nil {
 		return err
 	}
 
@@ -86,10 +87,10 @@ func (s *Service) verifyBlkPreState(ctx context.Context, b block.BeaconBlock) er
 	return nil
 }
 
-// VerifyBlkDescendant validates input block root is a descendant of the
+// VerifyFinalizedBlkDescendant validates if input block root is a descendant of the
 // current finalized block root.
-func (s *Service) VerifyBlkDescendant(ctx context.Context, root [32]byte) error {
-	ctx, span := trace.StartSpan(ctx, "blockChain.VerifyBlkDescendant")
+func (s *Service) VerifyFinalizedBlkDescendant(ctx context.Context, root [32]byte) error {
+	ctx, span := trace.StartSpan(ctx, "blockChain.VerifyFinalizedBlkDescendant")
 	defer span.End()
 	finalized := s.store.FinalizedCheckpt()
 	if finalized == nil {
@@ -402,10 +403,17 @@ func (s *Service) insertFinalizedDeposits(ctx context.Context, fRoot [32]byte) e
 	// We update the cache up to the last deposit index in the finalized block's state.
 	// We can be confident that these deposits will be included in some block
 	// because the Eth1 follow distance makes such long-range reorgs extremely unlikely.
-	eth1DepositIndex := int64(finalizedState.Eth1Data().DepositCount - 1)
-	s.cfg.DepositCache.InsertFinalizedDeposits(ctx, eth1DepositIndex)
+	eth1DepositIndex, err := mathutil.Int(finalizedState.Eth1DepositIndex())
+	if err != nil {
+		return errors.Wrap(err, "could not cast eth1 deposit index")
+	}
+	// The deposit index in the state is always the index of the next deposit
+	// to be included(rather than the last one to be processed). This was most likely
+	// done as the state cannot represent signed integers.
+	eth1DepositIndex -= 1
+	s.cfg.DepositCache.InsertFinalizedDeposits(ctx, int64(eth1DepositIndex))
 	// Deposit proofs are only used during state transition and can be safely removed to save space.
-	if err = s.cfg.DepositCache.PruneProofs(ctx, eth1DepositIndex); err != nil {
+	if err = s.cfg.DepositCache.PruneProofs(ctx, int64(eth1DepositIndex)); err != nil {
 		return errors.Wrap(err, "could not prune deposit proofs")
 	}
 	return nil

beacon-chain/blockchain/process_block_test.go

@@ -11,6 +11,7 @@ import (
 	"github.com/pkg/errors"
 	types "github.com/prysmaticlabs/eth2-types"
 	mock "github.com/prysmaticlabs/prysm/beacon-chain/blockchain/testing"
+	"github.com/prysmaticlabs/prysm/beacon-chain/cache"
 	"github.com/prysmaticlabs/prysm/beacon-chain/cache/depositcache"
 	"github.com/prysmaticlabs/prysm/beacon-chain/core/blocks"
 	"github.com/prysmaticlabs/prysm/beacon-chain/core/transition"
@@ -19,6 +20,7 @@ import (
 	doublylinkedtree "github.com/prysmaticlabs/prysm/beacon-chain/forkchoice/doubly-linked-tree"
 	"github.com/prysmaticlabs/prysm/beacon-chain/forkchoice/protoarray"
 	forkchoicetypes "github.com/prysmaticlabs/prysm/beacon-chain/forkchoice/types"
+	mockPOW "github.com/prysmaticlabs/prysm/beacon-chain/powchain/testing"
 	"github.com/prysmaticlabs/prysm/beacon-chain/state"
 	"github.com/prysmaticlabs/prysm/beacon-chain/state/stategen"
 	v1 "github.com/prysmaticlabs/prysm/beacon-chain/state/v1"
@@ -26,6 +28,7 @@ import (
 	fieldparams "github.com/prysmaticlabs/prysm/config/fieldparams"
 	"github.com/prysmaticlabs/prysm/config/params"
 	"github.com/prysmaticlabs/prysm/encoding/bytesutil"
+	enginev1 "github.com/prysmaticlabs/prysm/proto/engine/v1"
 	ethpb "github.com/prysmaticlabs/prysm/proto/prysm/v1alpha1"
 	"github.com/prysmaticlabs/prysm/proto/prysm/v1alpha1/block"
 	"github.com/prysmaticlabs/prysm/proto/prysm/v1alpha1/wrapper"
@@ -1340,7 +1343,7 @@ func TestVerifyBlkDescendant(t *testing.T) {
 		service, err := NewService(ctx, opts...)
 		require.NoError(t, err)
 		service.store.SetFinalizedCheckpt(&ethpb.Checkpoint{Root: tt.args.finalizedRoot[:]})
-		err = service.VerifyBlkDescendant(ctx, tt.args.parentRoot)
+		err = service.VerifyFinalizedBlkDescendant(ctx, tt.args.parentRoot)
 		if tt.wantedErr != "" {
 			assert.ErrorContains(t, tt.wantedErr, err)
 		} else if err != nil {
@@ -1516,6 +1519,7 @@ func TestInsertFinalizedDeposits(t *testing.T) {
 	service.store.SetFinalizedCheckpt(&ethpb.Checkpoint{Root: gRoot[:]})
 	gs = gs.Copy()
 	assert.NoError(t, gs.SetEth1Data(&ethpb.Eth1Data{DepositCount: 10}))
+	assert.NoError(t, gs.SetEth1DepositIndex(8))
 	assert.NoError(t, service.cfg.StateGen.SaveState(ctx, [32]byte{'m', 'o', 'c', 'k'}, gs))
 	zeroSig := [96]byte{}
 	for i := uint64(0); i < uint64(4*params.BeaconConfig().SlotsPerEpoch); i++ {
@@ -1529,8 +1533,64 @@ func TestInsertFinalizedDeposits(t *testing.T) {
 	}
 	assert.NoError(t, service.insertFinalizedDeposits(ctx, [32]byte{'m', 'o', 'c', 'k'}))
 	fDeposits := depositCache.FinalizedDeposits(ctx)
-	assert.Equal(t, 9, int(fDeposits.MerkleTrieIndex), "Finalized deposits not inserted correctly")
-	deps := depositCache.AllDeposits(ctx, big.NewInt(109))
+	assert.Equal(t, 7, int(fDeposits.MerkleTrieIndex), "Finalized deposits not inserted correctly")
+	deps := depositCache.AllDeposits(ctx, big.NewInt(107))
+	for _, d := range deps {
+		assert.DeepEqual(t, [][]byte(nil), d.Proof, "Proofs are not empty")
+	}
+}
+
+func TestInsertFinalizedDeposits_MultipleFinalizedRoutines(t *testing.T) {
+	ctx := context.Background()
+	opts := testServiceOptsWithDB(t)
+	depositCache, err := depositcache.New()
+	require.NoError(t, err)
+	opts = append(opts, WithDepositCache(depositCache))
+	service, err := NewService(ctx, opts...)
+	require.NoError(t, err)
+
+	gs, _ := util.DeterministicGenesisState(t, 32)
+	require.NoError(t, service.saveGenesisData(ctx, gs))
+	gBlk, err := service.cfg.BeaconDB.GenesisBlock(ctx)
+	require.NoError(t, err)
+	gRoot, err := gBlk.Block().HashTreeRoot()
+	require.NoError(t, err)
+	service.store.SetFinalizedCheckpt(&ethpb.Checkpoint{Root: gRoot[:]})
+	gs = gs.Copy()
+	assert.NoError(t, gs.SetEth1Data(&ethpb.Eth1Data{DepositCount: 7}))
+	assert.NoError(t, gs.SetEth1DepositIndex(6))
+	assert.NoError(t, service.cfg.StateGen.SaveState(ctx, [32]byte{'m', 'o', 'c', 'k'}, gs))
+	gs2 := gs.Copy()
+	assert.NoError(t, gs2.SetEth1Data(&ethpb.Eth1Data{DepositCount: 15}))
+	assert.NoError(t, gs2.SetEth1DepositIndex(13))
+	assert.NoError(t, service.cfg.StateGen.SaveState(ctx, [32]byte{'m', 'o', 'c', 'k', '2'}, gs2))
+	zeroSig := [96]byte{}
+	for i := uint64(0); i < uint64(4*params.BeaconConfig().SlotsPerEpoch); i++ {
+		root := []byte(strconv.Itoa(int(i)))
+		assert.NoError(t, depositCache.InsertDeposit(ctx, &ethpb.Deposit{Data: &ethpb.Deposit_Data{
+			PublicKey:             bytesutil.FromBytes48([fieldparams.BLSPubkeyLength]byte{}),
+			WithdrawalCredentials: params.BeaconConfig().ZeroHash[:],
+			Amount:                0,
+			Signature:             zeroSig[:],
+		}, Proof: [][]byte{root}}, 100+i, int64(i), bytesutil.ToBytes32(root)))
+	}
+	// Insert 3 deposits before hand.
+	depositCache.InsertFinalizedDeposits(ctx, 2)
+
+	assert.NoError(t, service.insertFinalizedDeposits(ctx, [32]byte{'m', 'o', 'c', 'k'}))
+	fDeposits := depositCache.FinalizedDeposits(ctx)
+	assert.Equal(t, 5, int(fDeposits.MerkleTrieIndex), "Finalized deposits not inserted correctly")
+
+	deps := depositCache.AllDeposits(ctx, big.NewInt(105))
+	for _, d := range deps {
+		assert.DeepEqual(t, [][]byte(nil), d.Proof, "Proofs are not empty")
+	}
+
+	// Insert New Finalized State with higher deposit count.
+	assert.NoError(t, service.insertFinalizedDeposits(ctx, [32]byte{'m', 'o', 'c', 'k', '2'}))
+	fDeposits = depositCache.FinalizedDeposits(ctx)
+	assert.Equal(t, 12, int(fDeposits.MerkleTrieIndex), "Finalized deposits not inserted correctly")
+	deps = depositCache.AllDeposits(ctx, big.NewInt(112))
 	for _, d := range deps {
 		assert.DeepEqual(t, [][]byte(nil), d.Proof, "Proofs are not empty")
 	}
@@ -1635,3 +1695,136 @@ func Test_getStateVersionAndPayload(t *testing.T) {
 		})
 	}
 }
+
+func Test_validateMergeTransitionBlock(t *testing.T) {
+	cfg := params.BeaconConfig()
+	cfg.TerminalTotalDifficulty = "2"
+	cfg.TerminalBlockHash = params.BeaconConfig().ZeroHash
+	params.OverrideBeaconConfig(cfg)
+
+	ctx := context.Background()
+	beaconDB := testDB.SetupDB(t)
+	fcs := protoarray.New(0, 0, [32]byte{'a'})
+	opts := []Option{
+		WithDatabase(beaconDB),
+		WithStateGen(stategen.New(beaconDB)),
+		WithForkChoiceStore(fcs),
+		WithProposerIdsCache(cache.NewProposerPayloadIDsCache()),
+	}
+	service, err := NewService(ctx, opts...)
+	require.NoError(t, err)
+
+	tests := []struct {
+		name         string
+		stateVersion int
+		header       *ethpb.ExecutionPayloadHeader
+		payload      *enginev1.ExecutionPayload
+		errString    string
+	}{
+		{
+			name:         "state older than Bellatrix, nil payload",
+			stateVersion: 1,
+			payload:      nil,
+		},
+		{
+			name:         "state older than Bellatrix, empty payload",
+			stateVersion: 1,
+			payload: &enginev1.ExecutionPayload{
+				ParentHash:    make([]byte, fieldparams.RootLength),
+				FeeRecipient:  make([]byte, fieldparams.FeeRecipientLength),
+				StateRoot:     make([]byte, fieldparams.RootLength),
+				ReceiptsRoot:  make([]byte, fieldparams.RootLength),
+				LogsBloom:     make([]byte, fieldparams.LogsBloomLength),
+				PrevRandao:    make([]byte, fieldparams.RootLength),
+				BaseFeePerGas: make([]byte, fieldparams.RootLength),
+				BlockHash:     make([]byte, fieldparams.RootLength),
+			},
+		},
+		{
+			name:         "state older than Bellatrix, non empty payload",
+			stateVersion: 1,
+			payload: &enginev1.ExecutionPayload{
+				ParentHash: bytesutil.PadTo([]byte{'a'}, fieldparams.RootLength),
+			},
+		},
+		{
+			name:         "state is Bellatrix, nil payload",
+			stateVersion: 2,
+			payload:      nil,
+		},
+		{
+			name:         "state is Bellatrix, empty payload",
+			stateVersion: 2,
+			payload: &enginev1.ExecutionPayload{
+				ParentHash:    make([]byte, fieldparams.RootLength),
+				FeeRecipient:  make([]byte, fieldparams.FeeRecipientLength),
+				StateRoot:     make([]byte, fieldparams.RootLength),
+				ReceiptsRoot:  make([]byte, fieldparams.RootLength),
+				LogsBloom:     make([]byte, fieldparams.LogsBloomLength),
+				PrevRandao:    make([]byte, fieldparams.RootLength),
+				BaseFeePerGas: make([]byte, fieldparams.RootLength),
+				BlockHash:     make([]byte, fieldparams.RootLength),
+			},
+		},
+		{
+			name:         "state is Bellatrix, non empty payload, empty header",
+			stateVersion: 2,
+			payload: &enginev1.ExecutionPayload{
+				ParentHash: bytesutil.PadTo([]byte{'a'}, fieldparams.RootLength),
+			},
+			header: &ethpb.ExecutionPayloadHeader{
+				ParentHash:       make([]byte, fieldparams.RootLength),
+				FeeRecipient:     make([]byte, fieldparams.FeeRecipientLength),
+				StateRoot:        make([]byte, fieldparams.RootLength),
+				ReceiptsRoot:     make([]byte, fieldparams.RootLength),
+				LogsBloom:        make([]byte, fieldparams.LogsBloomLength),
+				PrevRandao:       make([]byte, fieldparams.RootLength),
+				BaseFeePerGas:    make([]byte, fieldparams.RootLength),
+				BlockHash:        make([]byte, fieldparams.RootLength),
+				TransactionsRoot: make([]byte, fieldparams.RootLength),
+			},
+		},
+		{
+			name:         "state is Bellatrix, non empty payload, non empty header",
+			stateVersion: 2,
+			payload: &enginev1.ExecutionPayload{
+				ParentHash: bytesutil.PadTo([]byte{'a'}, fieldparams.RootLength),
+			},
+			header: &ethpb.ExecutionPayloadHeader{
+				BlockNumber: 1,
+			},
+		},
+		{
+			name:         "state is Bellatrix, non empty payload, nil header",
+			stateVersion: 2,
+			payload: &enginev1.ExecutionPayload{
+				ParentHash: bytesutil.PadTo([]byte{'a'}, fieldparams.RootLength),
+			},
+			errString: "nil header or block body",
+		},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			e := &mockPOW.EngineClient{BlockByHashMap: map[[32]byte]*enginev1.ExecutionBlock{}}
+			e.BlockByHashMap[[32]byte{'a'}] = &enginev1.ExecutionBlock{
+				ParentHash:      bytesutil.PadTo([]byte{'b'}, fieldparams.RootLength),
+				TotalDifficulty: "0x2",
+			}
+			e.BlockByHashMap[[32]byte{'b'}] = &enginev1.ExecutionBlock{
+				ParentHash:      bytesutil.PadTo([]byte{'3'}, fieldparams.RootLength),
+				TotalDifficulty: "0x1",
+			}
+			service.cfg.ExecutionEngineCaller = e
+			b := util.HydrateSignedBeaconBlockBellatrix(&ethpb.SignedBeaconBlockBellatrix{})
+			b.Block.Body.ExecutionPayload = tt.payload
+			blk, err := wrapper.WrappedSignedBeaconBlock(b)
+			require.NoError(t, err)
+			err = service.validateMergeTransitionBlock(ctx, tt.stateVersion, tt.header, blk)
+			if tt.errString != "" {
+				require.ErrorContains(t, tt.errString, err)
+			} else {
+				require.NoError(t, err)
+			}
+		})
+	}
+}

beacon-chain/blockchain/receive_attestation.go

@@ -28,27 +28,10 @@ type AttestationStateFetcher interface {
 // AttestationReceiver interface defines the methods of chain service receive and processing new attestations.
 type AttestationReceiver interface {
 	AttestationStateFetcher
-	ReceiveAttestationNoPubsub(ctx context.Context, att *ethpb.Attestation) error
 	VerifyLmdFfgConsistency(ctx context.Context, att *ethpb.Attestation) error
 	VerifyFinalizedConsistency(ctx context.Context, root []byte) error
 }
 
-// ReceiveAttestationNoPubsub is a function that defines the operations that are performed on
-// attestation that is received from regular sync. The operations consist of:
-//  1. Validate attestation, update validator's latest vote
-//  2. Apply fork choice to the processed attestation
-//  3. Save latest head info
-func (s *Service) ReceiveAttestationNoPubsub(ctx context.Context, att *ethpb.Attestation) error {
-	ctx, span := trace.StartSpan(ctx, "beacon-chain.blockchain.ReceiveAttestationNoPubsub")
-	defer span.End()
-
-	if err := s.OnAttestation(ctx, att); err != nil {
-		return errors.Wrap(err, "could not process attestation")
-	}
-
-	return nil
-}
-
 // AttestationTargetState returns the pre state of attestation.
 func (s *Service) AttestationTargetState(ctx context.Context, target *ethpb.Checkpoint) (state.BeaconState, error) {
 	ss, err := slots.EpochStart(target.Epoch)
@@ -83,7 +66,8 @@ func (s *Service) VerifyLmdFfgConsistency(ctx context.Context, a *ethpb.Attestat
 func (s *Service) VerifyFinalizedConsistency(ctx context.Context, root []byte) error {
 	// A canonical root implies the root to has an ancestor that aligns with finalized check point.
 	// In this case, we could exit early to save on additional computation.
-	if s.cfg.ForkChoiceStore.IsCanonical(bytesutil.ToBytes32(root)) {
+	blockRoot := bytesutil.ToBytes32(root)
+	if s.cfg.ForkChoiceStore.HasNode(blockRoot) && s.cfg.ForkChoiceStore.IsCanonical(blockRoot) {
 		return nil
 	}
 
@@ -186,11 +170,23 @@ func (s *Service) notifyEngineIfChangedHead(ctx context.Context, newHeadRoot [32
 		log.WithError(err).Error("Could not get block from db")
 		return
 	}
+	if newHeadBlock == nil || newHeadBlock.IsNil() {
+		log.WithFields(logrus.Fields{
+			"root": fmt.Sprintf("%#x", newHeadRoot),
+		}).Error("Block with root not found in database when notifying engine of head change")
+		return
+	}
 	headState, err := s.cfg.StateGen.StateByRoot(ctx, newHeadRoot)
 	if err != nil {
 		log.WithError(err).Error("Could not get state from db")
 		return
 	}
+	if headState == nil || headState.IsNil() {
+		log.WithFields(logrus.Fields{
+			"root": fmt.Sprintf("%#x", newHeadRoot),
+		}).Error("State for block with root not found in database when notifying engine of head change")
+		return
+	}
 	_, err = s.notifyForkchoiceUpdate(s.ctx,
 		headState,
 		newHeadBlock.Block(),
@@ -231,7 +227,7 @@ func (s *Service) processAttestations(ctx context.Context) {
 			continue
 		}
 
-		if err := s.ReceiveAttestationNoPubsub(ctx, a); err != nil {
+		if err := s.receiveAttestationNoPubsub(ctx, a); err != nil {
 			log.WithFields(logrus.Fields{
 				"slot":             a.Data.Slot,
 				"committeeIndex":   a.Data.CommitteeIndex,
@@ -242,3 +238,19 @@ func (s *Service) processAttestations(ctx context.Context) {
 		}
 	}
 }
+
+// receiveAttestationNoPubsub is a function that defines the operations that are performed on
+// attestation that is received from regular sync. The operations consist of:
+//  1. Validate attestation, update validator's latest vote
+//  2. Apply fork choice to the processed attestation
+//  3. Save latest head info
+func (s *Service) receiveAttestationNoPubsub(ctx context.Context, att *ethpb.Attestation) error {
+	ctx, span := trace.StartSpan(ctx, "beacon-chain.blockchain.receiveAttestationNoPubsub")
+	defer span.End()
+
+	if err := s.OnAttestation(ctx, att); err != nil {
+		return errors.Wrap(err, "could not process attestation")
+	}
+
+	return nil
+}

beacon-chain/blockchain/receive_block.go

@@ -17,7 +17,7 @@ import (
 // This defines how many epochs since finality the run time will begin to save hot state on to the DB.
 var epochsSinceFinalitySaveHotStateDB = types.Epoch(100)
 
-// BlockReceiver interface defines the methods of chain service receive and processing new blocks.
+// BlockReceiver interface defines the methods of chain service for receiving and processing new blocks.
 type BlockReceiver interface {
 	ReceiveBlock(ctx context.Context, block block.SignedBeaconBlock, blockRoot [32]byte) error
 	ReceiveBlockBatch(ctx context.Context, blocks []block.SignedBeaconBlock, blkRoots [][32]byte) error
@@ -78,7 +78,7 @@ func (s *Service) ReceiveBlockBatch(ctx context.Context, blocks []block.SignedBe
 	ctx, span := trace.StartSpan(ctx, "blockChain.ReceiveBlockBatch")
 	defer span.End()
 
-	// Apply state transition on the incoming newly received blockCopy without verifying its BLS contents.
+	// Apply state transition on the incoming newly received block batches, one by one.
 	fCheckpoints, jCheckpoints, err := s.onBlockBatch(ctx, blocks, blkRoots)
 	if err != nil {
 		err := errors.Wrap(err, "could not process block in batch")

beacon-chain/blockchain/service.go

@@ -50,14 +50,13 @@ const headSyncMinEpochsAfterCheckpoint = 128
 // Service represents a service that handles the internal
 // logic of managing the full PoS beacon chain.
 type Service struct {
-	cfg         *config
-	ctx         context.Context
-	cancel      context.CancelFunc
-	genesisTime time.Time
-	head        *head
-	headLock    sync.RWMutex
-	// originBlockRoot is the genesis root, or weak subjectivity checkpoint root, depending on how the node is initialized
-	originBlockRoot       [32]byte
+	cfg                   *config
+	ctx                   context.Context
+	cancel                context.CancelFunc
+	genesisTime           time.Time
+	head                  *head
+	headLock              sync.RWMutex
+	originBlockRoot       [32]byte // genesis root, or weak subjectivity checkpoint root, depending on how the node is initialized
 	nextEpochBoundarySlot types.Slot
 	boundaryRoots         [][32]byte
 	checkpointStateCache  *cache.CheckpointStateCache
@@ -160,11 +159,12 @@ func (s *Service) Status() error {
 		return errors.New("genesis state has not been created")
 	}
 	if runtime.NumGoroutine() > s.cfg.MaxRoutines {
-		return fmt.Errorf("too many goroutines %d", runtime.NumGoroutine())
+		return fmt.Errorf("too many goroutines (%d)", runtime.NumGoroutine())
 	}
 	return nil
 }
 
+// StartFromSavedState initializes the blockchain using a previously saved finalized checkpoint.
 func (s *Service) StartFromSavedState(saved state.BeaconState) error {
 	log.Info("Blockchain data already exists in DB, initializing...")
 	s.genesisTime = time.Unix(int64(saved.GenesisTime()), 0) // lint:ignore uintcast -- Genesis time will not exceed int64 in your lifetime.
@@ -191,14 +191,14 @@ func (s *Service) StartFromSavedState(saved state.BeaconState) error {
 	}
 	s.store = store.New(justified, finalized)
 
-	var f f.ForkChoicer
+	var forkChoicer f.ForkChoicer
 	fRoot := bytesutil.ToBytes32(finalized.Root)
 	if features.Get().EnableForkChoiceDoublyLinkedTree {
-		f = doublylinkedtree.New(justified.Epoch, finalized.Epoch)
+		forkChoicer = doublylinkedtree.New(justified.Epoch, finalized.Epoch)
 	} else {
-		f = protoarray.New(justified.Epoch, finalized.Epoch, fRoot)
+		forkChoicer = protoarray.New(justified.Epoch, finalized.Epoch, fRoot)
 	}
-	s.cfg.ForkChoiceStore = f
+	s.cfg.ForkChoiceStore = forkChoicer
 	fb, err := s.cfg.BeaconDB.Block(s.ctx, s.ensureRootNotZeros(fRoot))
 	if err != nil {
 		return errors.Wrap(err, "could not get finalized checkpoint block")
@@ -211,7 +211,7 @@ func (s *Service) StartFromSavedState(saved state.BeaconState) error {
 		return errors.Wrap(err, "could not get execution payload hash")
 	}
 	fSlot := fb.Block().Slot()
-	if err := f.InsertOptimisticBlock(s.ctx, fSlot, fRoot, params.BeaconConfig().ZeroHash,
+	if err := forkChoicer.InsertOptimisticBlock(s.ctx, fSlot, fRoot, params.BeaconConfig().ZeroHash,
 		payloadHash, justified.Epoch, finalized.Epoch); err != nil {
 		return errors.Wrap(err, "could not insert finalized block to forkchoice")
 	}
@@ -221,7 +221,7 @@ func (s *Service) StartFromSavedState(saved state.BeaconState) error {
 		return errors.Wrap(err, "could not get last validated checkpoint")
 	}
 	if bytes.Equal(finalized.Root, lastValidatedCheckpoint.Root) {
-		if err := f.SetOptimisticToValid(s.ctx, fRoot); err != nil {
+		if err := forkChoicer.SetOptimisticToValid(s.ctx, fRoot); err != nil {
 			return errors.Wrap(err, "could not set finalized block as validated")
 		}
 	}
@@ -281,9 +281,9 @@ func (s *Service) originRootFromSavedState(ctx context.Context) ([32]byte, error
 	return genesisBlkRoot, nil
 }
 
-// initializeHeadFromDB uses the finalized checkpoint and head block found in the database to set the current head
-// note that this may block until stategen replays blocks between the finalized and head blocks
-// if the head sync flag was specified and the gap between the finalized and head blocks is at least 128 epochs long
+// initializeHeadFromDB uses the finalized checkpoint and head block found in the database to set the current head.
+// Note that this may block until stategen replays blocks between the finalized and head blocks
+// if the head sync flag was specified and the gap between the finalized and head blocks is at least 128 epochs long.
 func (s *Service) initializeHeadFromDB(ctx context.Context) error {
 	finalized, err := s.cfg.BeaconDB.FinalizedCheckpoint(ctx)
 	if err != nil {

beacon-chain/blockchain/service_norace_test.go

@@ -2,7 +2,7 @@ package blockchain
 
 import (
 	"context"
-	"io/ioutil"
+	"io"
 	"testing"
 
 	testDB "github.com/prysmaticlabs/prysm/beacon-chain/db/testing"
@@ -14,7 +14,7 @@ import (
 
 func init() {
 	logrus.SetLevel(logrus.DebugLevel)
-	logrus.SetOutput(ioutil.Discard)
+	logrus.SetOutput(io.Discard)
 }
 
 func TestChainService_SaveHead_DataRace(t *testing.T) {

beacon-chain/blockchain/store/new.go

@@ -4,6 +4,7 @@ import (
 	ethpb "github.com/prysmaticlabs/prysm/proto/prysm/v1alpha1"
 )
 
+// New creates a store object.
 func New(justifiedCheckpt *ethpb.Checkpoint, finalizedCheckpt *ethpb.Checkpoint) *Store {
 	return &Store{
 		justifiedCheckpt:     justifiedCheckpt,

beacon-chain/blockchain/testing/mock.go

@@ -301,11 +301,6 @@ func (_ *ChainService) ReceiveAttestation(_ context.Context, _ *ethpb.Attestatio
 	return nil
 }
 
-// ReceiveAttestationNoPubsub mocks ReceiveAttestationNoPubsub method in chain service.
-func (_ *ChainService) ReceiveAttestationNoPubsub(context.Context, *ethpb.Attestation) error {
-	return nil
-}
-
 // AttestationTargetState mocks AttestationTargetState method in chain service.
 func (s *ChainService) AttestationTargetState(_ context.Context, _ *ethpb.Checkpoint) (state.BeaconState, error) {
 	return s.State, nil
@@ -319,11 +314,6 @@ func (s *ChainService) HeadValidatorsIndices(ctx context.Context, epoch types.Ep
 	return helpers.ActiveValidatorIndices(ctx, s.State, epoch)
 }
 
-// HeadSeed mocks the same method in the chain service.
-func (s *ChainService) HeadSeed(_ context.Context, epoch types.Epoch) ([32]byte, error) {
-	return helpers.Seed(s.State, epoch, params.BeaconConfig().DomainBeaconAttester)
-}
-
 // HeadETH1Data provides the current ETH1Data of the head state.
 func (s *ChainService) HeadETH1Data() *ethpb.Eth1Data {
 	return s.ETH1Data
@@ -381,7 +371,7 @@ func (_ *ChainService) HeadGenesisValidatorsRoot() [32]byte {
 }
 
 // VerifyBlkDescendant mocks VerifyBlkDescendant and always returns nil.
-func (s *ChainService) VerifyBlkDescendant(_ context.Context, _ [32]byte) error {
+func (s *ChainService) VerifyFinalizedBlkDescendant(_ context.Context, _ [32]byte) error {
 	return s.VerifyBlkDescendantErr
 }
 

beacon-chain/blockchain/weak_subjectivity_checks.go

@@ -32,9 +32,6 @@ type WeakSubjectivityVerifier struct {
 
 // NewWeakSubjectivityVerifier validates a checkpoint, and if valid, uses it to initialize a weak subjectivity verifier
 func NewWeakSubjectivityVerifier(wsc *ethpb.Checkpoint, db weakSubjectivityDB) (*WeakSubjectivityVerifier, error) {
-	// TODO(7342): Weak subjectivity checks are currently optional. When we require the flag to be specified
-	// per 7342, a nil checkpoint, zero-root or zero-epoch should all fail validation
-	// and return an error instead of creating a WeakSubjectivityVerifier that permits any chain history.
 	if wsc == nil || len(wsc.Root) == 0 || wsc.Epoch == 0 {
 		log.Warn("No valid weak subjectivity checkpoint specified, running without weak subjectivity verification")
 		return &WeakSubjectivityVerifier{

beacon-chain/cache/BUILD.bazel

@@ -33,7 +33,6 @@ go_library(
     deps = [
         "//beacon-chain/state:go_default_library",
         "//cache/lru:go_default_library",
-        "//config/features:go_default_library",
         "//config/params:go_default_library",
         "//container/slice:go_default_library",
         "//crypto/hash:go_default_library",
@@ -77,7 +76,6 @@ go_test(
         "//beacon-chain/state/v1:go_default_library",
         "//beacon-chain/state/v2:go_default_library",
         "//beacon-chain/state/v3:go_default_library",
-        "//config/features:go_default_library",
         "//config/fieldparams:go_default_library",
         "//config/params:go_default_library",
         "//encoding/bytesutil:go_default_library",

beacon-chain/cache/active_balance.go

@@ -14,7 +14,6 @@ import (
 	ethTypes "github.com/prysmaticlabs/eth2-types"
 	"github.com/prysmaticlabs/prysm/beacon-chain/state"
 	lruwrpr "github.com/prysmaticlabs/prysm/cache/lru"
-	"github.com/prysmaticlabs/prysm/config/features"
 	"github.com/prysmaticlabs/prysm/config/params"
 )
 
@@ -51,9 +50,6 @@ func NewEffectiveBalanceCache() *BalanceCache {
 
 // AddTotalEffectiveBalance adds a new total effective balance entry for current balance for state `st` into the cache.
 func (c *BalanceCache) AddTotalEffectiveBalance(st state.ReadOnlyBeaconState, balance uint64) error {
-	if !features.Get().EnableActiveBalanceCache {
-		return nil
-	}
 	key, err := balanceCacheKey(st)
 	if err != nil {
 		return err
@@ -68,9 +64,6 @@ func (c *BalanceCache) AddTotalEffectiveBalance(st state.ReadOnlyBeaconState, ba
 
 // Get returns the current epoch's effective balance for state `st` in cache.
 func (c *BalanceCache) Get(st state.ReadOnlyBeaconState) (uint64, error) {
-	if !features.Get().EnableActiveBalanceCache {
-		return 0, ErrNotFound
-	}
 	key, err := balanceCacheKey(st)
 	if err != nil {
 		return 0, err

beacon-chain/cache/active_balance_test.go

@@ -7,18 +7,12 @@ import (
 
 	types "github.com/prysmaticlabs/eth2-types"
 	state "github.com/prysmaticlabs/prysm/beacon-chain/state/v1"
-	"github.com/prysmaticlabs/prysm/config/features"
 	"github.com/prysmaticlabs/prysm/config/params"
 	ethpb "github.com/prysmaticlabs/prysm/proto/prysm/v1alpha1"
 	"github.com/prysmaticlabs/prysm/testing/require"
 )
 
 func TestBalanceCache_AddGetBalance(t *testing.T) {
-	resetCfg := features.InitWithReset(&features.Flags{
-		EnableActiveBalanceCache: true,
-	})
-	defer resetCfg()
-
 	blockRoots := make([][]byte, params.BeaconConfig().SlotsPerHistoricalRoot)
 	for i := 0; i < len(blockRoots); i++ {
 		b := make([]byte, 8)

beacon-chain/cache/depositcache/deposits_cache.go

@@ -36,7 +36,7 @@ type DepositFetcher interface {
 	DepositByPubkey(ctx context.Context, pubKey []byte) (*ethpb.Deposit, *big.Int)
 	DepositsNumberAndRootAtHeight(ctx context.Context, blockHeight *big.Int) (uint64, [32]byte)
 	FinalizedDeposits(ctx context.Context) *FinalizedDeposits
-	NonFinalizedDeposits(ctx context.Context, untilBlk *big.Int) []*ethpb.Deposit
+	NonFinalizedDeposits(ctx context.Context, lastFinalizedIndex int64, untilBlk *big.Int) []*ethpb.Deposit
 }
 
 // FinalizedDeposits stores the trie of deposits that have been included
@@ -137,6 +137,22 @@ func (dc *DepositCache) InsertFinalizedDeposits(ctx context.Context, eth1Deposit
 
 	depositTrie := dc.finalizedDeposits.Deposits
 	insertIndex := int(dc.finalizedDeposits.MerkleTrieIndex + 1)
+
+	// Don't insert into finalized trie if there is no deposit to
+	// insert.
+	if len(dc.deposits) == 0 {
+		return
+	}
+	// In the event we have less deposits than we need to
+	// finalize we finalize till the index on which we do have it.
+	if len(dc.deposits) <= int(eth1DepositIndex) {
+		eth1DepositIndex = int64(len(dc.deposits)) - 1
+	}
+	// If we finalize to some lower deposit index, we
+	// ignore it.
+	if int(eth1DepositIndex) < insertIndex {
+		return
+	}
 	for _, d := range dc.deposits {
 		if d.Index <= dc.finalizedDeposits.MerkleTrieIndex {
 			continue
@@ -246,7 +262,7 @@ func (dc *DepositCache) FinalizedDeposits(ctx context.Context) *FinalizedDeposit
 
 // NonFinalizedDeposits returns the list of non-finalized deposits until the given block number (inclusive).
 // If no block is specified then this method returns all non-finalized deposits.
-func (dc *DepositCache) NonFinalizedDeposits(ctx context.Context, untilBlk *big.Int) []*ethpb.Deposit {
+func (dc *DepositCache) NonFinalizedDeposits(ctx context.Context, lastFinalizedIndex int64, untilBlk *big.Int) []*ethpb.Deposit {
 	ctx, span := trace.StartSpan(ctx, "DepositsCache.NonFinalizedDeposits")
 	defer span.End()
 	dc.depositsLock.RLock()
@@ -256,10 +272,9 @@ func (dc *DepositCache) NonFinalizedDeposits(ctx context.Context, untilBlk *big.
 		return dc.allDeposits(untilBlk)
 	}
 
-	lastFinalizedDepositIndex := dc.finalizedDeposits.MerkleTrieIndex
 	var deposits []*ethpb.Deposit
 	for _, d := range dc.deposits {
-		if (d.Index > lastFinalizedDepositIndex) && (untilBlk == nil || untilBlk.Uint64() >= d.Eth1BlockHeight) {
+		if (d.Index > lastFinalizedIndex) && (untilBlk == nil || untilBlk.Uint64() >= d.Eth1BlockHeight) {
 			deposits = append(deposits, d.Deposit)
 		}
 	}

beacon-chain/cache/depositcache/deposits_cache_test.go

@@ -459,7 +459,7 @@ func TestFinalizedDeposits_UtilizesPreviouslyCachedDeposits(t *testing.T) {
 			Index: 1,
 		},
 	}
-	newFinalizedDeposit := ethpb.DepositContainer{
+	newFinalizedDeposit := &ethpb.DepositContainer{
 		Deposit: &ethpb.Deposit{
 			Data: &ethpb.Deposit_Data{
 				PublicKey:             bytesutil.PadTo([]byte{2}, 48),
@@ -471,17 +471,17 @@ func TestFinalizedDeposits_UtilizesPreviouslyCachedDeposits(t *testing.T) {
 	}
 	dc.deposits = oldFinalizedDeposits
 	dc.InsertFinalizedDeposits(context.Background(), 1)
-	// Artificially exclude old deposits so that they can only be retrieved from previously finalized deposits.
-	dc.deposits = []*ethpb.DepositContainer{&newFinalizedDeposit}
 
 	dc.InsertFinalizedDeposits(context.Background(), 2)
 
+	dc.deposits = append(dc.deposits, []*ethpb.DepositContainer{newFinalizedDeposit}...)
+
 	cachedDeposits := dc.FinalizedDeposits(context.Background())
 	require.NotNil(t, cachedDeposits, "Deposits not cached")
-	assert.Equal(t, int64(2), cachedDeposits.MerkleTrieIndex)
+	assert.Equal(t, int64(1), cachedDeposits.MerkleTrieIndex)
 
 	var deps [][]byte
-	for _, d := range append(oldFinalizedDeposits, &newFinalizedDeposit) {
+	for _, d := range oldFinalizedDeposits {
 		hash, err := d.Deposit.Data.HashTreeRoot()
 		require.NoError(t, err, "Could not hash deposit data")
 		deps = append(deps, hash[:])
@@ -491,6 +491,140 @@ func TestFinalizedDeposits_UtilizesPreviouslyCachedDeposits(t *testing.T) {
 	assert.Equal(t, trie.HashTreeRoot(), cachedDeposits.Deposits.HashTreeRoot())
 }
 
+func TestFinalizedDeposits_HandleZeroDeposits(t *testing.T) {
+	dc, err := New()
+	require.NoError(t, err)
+
+	dc.InsertFinalizedDeposits(context.Background(), 2)
+
+	cachedDeposits := dc.FinalizedDeposits(context.Background())
+	require.NotNil(t, cachedDeposits, "Deposits not cached")
+	assert.Equal(t, int64(-1), cachedDeposits.MerkleTrieIndex)
+}
+
+func TestFinalizedDeposits_HandleSmallerThanExpectedDeposits(t *testing.T) {
+	dc, err := New()
+	require.NoError(t, err)
+
+	finalizedDeposits := []*ethpb.DepositContainer{
+		{
+			Deposit: &ethpb.Deposit{
+				Data: &ethpb.Deposit_Data{
+					PublicKey:             bytesutil.PadTo([]byte{0}, 48),
+					WithdrawalCredentials: make([]byte, 32),
+					Signature:             make([]byte, 96),
+				},
+			},
+			Index: 0,
+		},
+		{
+			Deposit: &ethpb.Deposit{
+				Data: &ethpb.Deposit_Data{
+					PublicKey:             bytesutil.PadTo([]byte{1}, 48),
+					WithdrawalCredentials: make([]byte, 32),
+					Signature:             make([]byte, 96),
+				},
+			},
+			Index: 1,
+		},
+		{
+			Deposit: &ethpb.Deposit{
+				Data: &ethpb.Deposit_Data{
+					PublicKey:             bytesutil.PadTo([]byte{2}, 48),
+					WithdrawalCredentials: make([]byte, 32),
+					Signature:             make([]byte, 96),
+				},
+			},
+			Index: 2,
+		},
+	}
+	dc.deposits = finalizedDeposits
+
+	dc.InsertFinalizedDeposits(context.Background(), 5)
+
+	cachedDeposits := dc.FinalizedDeposits(context.Background())
+	require.NotNil(t, cachedDeposits, "Deposits not cached")
+	assert.Equal(t, int64(2), cachedDeposits.MerkleTrieIndex)
+}
+
+func TestFinalizedDeposits_HandleLowerEth1DepositIndex(t *testing.T) {
+	dc, err := New()
+	require.NoError(t, err)
+
+	finalizedDeposits := []*ethpb.DepositContainer{
+		{
+			Deposit: &ethpb.Deposit{
+				Data: &ethpb.Deposit_Data{
+					PublicKey:             bytesutil.PadTo([]byte{0}, 48),
+					WithdrawalCredentials: make([]byte, 32),
+					Signature:             make([]byte, 96),
+				},
+			},
+			Index: 0,
+		},
+		{
+			Deposit: &ethpb.Deposit{
+				Data: &ethpb.Deposit_Data{
+					PublicKey:             bytesutil.PadTo([]byte{1}, 48),
+					WithdrawalCredentials: make([]byte, 32),
+					Signature:             make([]byte, 96),
+				},
+			},
+			Index: 1,
+		},
+		{
+			Deposit: &ethpb.Deposit{
+				Data: &ethpb.Deposit_Data{
+					PublicKey:             bytesutil.PadTo([]byte{2}, 48),
+					WithdrawalCredentials: make([]byte, 32),
+					Signature:             make([]byte, 96),
+				},
+			},
+			Index: 2,
+		},
+		{
+			Deposit: &ethpb.Deposit{
+				Data: &ethpb.Deposit_Data{
+					PublicKey:             bytesutil.PadTo([]byte{3}, 48),
+					WithdrawalCredentials: make([]byte, 32),
+					Signature:             make([]byte, 96),
+				},
+			},
+			Index: 3,
+		},
+		{
+			Deposit: &ethpb.Deposit{
+				Data: &ethpb.Deposit_Data{
+					PublicKey:             bytesutil.PadTo([]byte{4}, 48),
+					WithdrawalCredentials: make([]byte, 32),
+					Signature:             make([]byte, 96),
+				},
+			},
+			Index: 4,
+		},
+		{
+			Deposit: &ethpb.Deposit{
+				Data: &ethpb.Deposit_Data{
+					PublicKey:             bytesutil.PadTo([]byte{5}, 48),
+					WithdrawalCredentials: make([]byte, 32),
+					Signature:             make([]byte, 96),
+				},
+			},
+			Index: 5,
+		},
+	}
+	dc.deposits = finalizedDeposits
+
+	dc.InsertFinalizedDeposits(context.Background(), 5)
+
+	// Reinsert finalized deposits with a lower index.
+	dc.InsertFinalizedDeposits(context.Background(), 2)
+
+	cachedDeposits := dc.FinalizedDeposits(context.Background())
+	require.NotNil(t, cachedDeposits, "Deposits not cached")
+	assert.Equal(t, int64(5), cachedDeposits.MerkleTrieIndex)
+}
+
 func TestFinalizedDeposits_InitializedCorrectly(t *testing.T) {
 	dc, err := New()
 	require.NoError(t, err)
@@ -554,7 +688,7 @@ func TestNonFinalizedDeposits_ReturnsAllNonFinalizedDeposits(t *testing.T) {
 		})
 	dc.InsertFinalizedDeposits(context.Background(), 1)
 
-	deps := dc.NonFinalizedDeposits(context.Background(), nil)
+	deps := dc.NonFinalizedDeposits(context.Background(), 1, nil)
 	assert.Equal(t, 2, len(deps))
 }
 
@@ -611,10 +745,89 @@ func TestNonFinalizedDeposits_ReturnsNonFinalizedDepositsUpToBlockNumber(t *test
 		})
 	dc.InsertFinalizedDeposits(context.Background(), 1)
 
-	deps := dc.NonFinalizedDeposits(context.Background(), big.NewInt(10))
+	deps := dc.NonFinalizedDeposits(context.Background(), 1, big.NewInt(10))
 	assert.Equal(t, 1, len(deps))
 }
 
+func TestFinalizedDeposits_ReturnsTrieCorrectly(t *testing.T) {
+	dc, err := New()
+	require.NoError(t, err)
+
+	generateCtr := func(height uint64, index int64) *ethpb.DepositContainer {
+		return &ethpb.DepositContainer{
+			Eth1BlockHeight: height,
+			Deposit: &ethpb.Deposit{
+				Data: &ethpb.Deposit_Data{
+					PublicKey:             bytesutil.PadTo([]byte{uint8(index)}, 48),
+					WithdrawalCredentials: make([]byte, 32),
+					Signature:             make([]byte, 96),
+				},
+			},
+			Index: index,
+		}
+	}
+
+	finalizedDeposits := []*ethpb.DepositContainer{
+		generateCtr(10, 0),
+		generateCtr(11, 1),
+		generateCtr(12, 2),
+		generateCtr(12, 3),
+		generateCtr(13, 4),
+		generateCtr(13, 5),
+		generateCtr(13, 6),
+		generateCtr(14, 7),
+	}
+	dc.deposits = append(finalizedDeposits,
+		generateCtr(15, 8),
+		generateCtr(15, 9),
+		generateCtr(30, 10))
+	trieItems := make([][]byte, 0, len(dc.deposits))
+	for _, dep := range dc.allDeposits(big.NewInt(30)) {
+		depHash, err := dep.Data.HashTreeRoot()
+		assert.NoError(t, err)
+		trieItems = append(trieItems, depHash[:])
+	}
+	depositTrie, err := trie.GenerateTrieFromItems(trieItems, params.BeaconConfig().DepositContractTreeDepth)
+	assert.NoError(t, err)
+
+	// Perform this in a non-sensical ordering
+	dc.InsertFinalizedDeposits(context.Background(), 10)
+	dc.InsertFinalizedDeposits(context.Background(), 2)
+	dc.InsertFinalizedDeposits(context.Background(), 3)
+	dc.InsertFinalizedDeposits(context.Background(), 4)
+
+	// Mimick finalized deposit trie fetch.
+	fd := dc.FinalizedDeposits(context.Background())
+	deps := dc.NonFinalizedDeposits(context.Background(), fd.MerkleTrieIndex, big.NewInt(14))
+	insertIndex := fd.MerkleTrieIndex + 1
+
+	for _, dep := range deps {
+		depHash, err := dep.Data.HashTreeRoot()
+		assert.NoError(t, err)
+		if err = fd.Deposits.Insert(depHash[:], int(insertIndex)); err != nil {
+			assert.NoError(t, err)
+		}
+		insertIndex++
+	}
+	dc.InsertFinalizedDeposits(context.Background(), 15)
+	dc.InsertFinalizedDeposits(context.Background(), 15)
+	dc.InsertFinalizedDeposits(context.Background(), 14)
+
+	fd = dc.FinalizedDeposits(context.Background())
+	deps = dc.NonFinalizedDeposits(context.Background(), fd.MerkleTrieIndex, big.NewInt(30))
+	insertIndex = fd.MerkleTrieIndex + 1
+
+	for _, dep := range deps {
+		depHash, err := dep.Data.HashTreeRoot()
+		assert.NoError(t, err)
+		if err = fd.Deposits.Insert(depHash[:], int(insertIndex)); err != nil {
+			assert.NoError(t, err)
+		}
+		insertIndex++
+	}
+	assert.Equal(t, fd.Deposits.NumOfItems(), depositTrie.NumOfItems())
+}
+
 func TestPruneProofs_Ok(t *testing.T) {
 	dc, err := New()
 	require.NoError(t, err)

beacon-chain/core/blocks/attestation_regression_test.go

@@ -2,7 +2,7 @@ package blocks_test
 
 import (
 	"context"
-	"io/ioutil"
+	"os"
 	"testing"
 
 	"github.com/prysmaticlabs/go-bitfield"
@@ -20,7 +20,7 @@ import (
 // valid att.Data.Committee index would be 0, so this is an off by one error.
 // See: https://github.com/sigp/beacon-fuzz/issues/78
 func TestProcessAttestationNoVerifySignature_BeaconFuzzIssue78(t *testing.T) {
-	attData, err := ioutil.ReadFile("testdata/beaconfuzz_78_attestation.ssz")
+	attData, err := os.ReadFile("testdata/beaconfuzz_78_attestation.ssz")
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -28,7 +28,7 @@ func TestProcessAttestationNoVerifySignature_BeaconFuzzIssue78(t *testing.T) {
 	if err := att.UnmarshalSSZ(attData); err != nil {
 		t.Fatal(err)
 	}
-	stateData, err := ioutil.ReadFile("testdata/beaconfuzz_78_beacon.ssz")
+	stateData, err := os.ReadFile("testdata/beaconfuzz_78_beacon.ssz")
 	if err != nil {
 		t.Fatal(err)
 	}

beacon-chain/core/blocks/header_test.go

@@ -2,7 +2,7 @@ package blocks_test
 
 import (
 	"context"
-	"io/ioutil"
+	"io"
 	"testing"
 
 	"github.com/prysmaticlabs/prysm/beacon-chain/core/blocks"
@@ -23,7 +23,7 @@ import (
 )
 
 func init() {
-	logrus.SetOutput(ioutil.Discard) // Ignore "validator activated" logs
+	logrus.SetOutput(io.Discard) // Ignore "validator activated" logs
 }
 
 func TestProcessBlockHeader_ImproperBlockSlot(t *testing.T) {

beacon-chain/core/blocks/payload.go

@@ -18,6 +18,12 @@ import (
 	"github.com/prysmaticlabs/prysm/time/slots"
 )
 
+var (
+	ErrInvalidPayloadBlockHash  = errors.New("invalid payload block hash")
+	ErrInvalidPayloadTimeStamp  = errors.New("invalid payload timestamp")
+	ErrInvalidPayloadPrevRandao = errors.New("invalid payload previous randao")
+)
+
 // IsMergeTransitionComplete returns true if the transition to Bellatrix has completed.
 // Meaning the payload header in beacon state is not `ExecutionPayloadHeader()` (i.e. not empty).
 //
@@ -68,7 +74,7 @@ func IsExecutionBlock(body block.BeaconBlockBody) (bool, error) {
 		return false, err
 	default:
 	}
-	return !isEmptyPayload(payload), nil
+	return !IsEmptyPayload(payload), nil
 }
 
 // IsExecutionEnabled returns true if the beacon chain can begin executing.
@@ -146,14 +152,14 @@ func ValidatePayload(st state.BeaconState, payload *enginev1.ExecutionPayload) e
 	}
 
 	if !bytes.Equal(payload.PrevRandao, random) {
-		return errors.New("incorrect prev randao")
+		return ErrInvalidPayloadPrevRandao
 	}
 	t, err := slots.ToTime(st.GenesisTime(), st.Slot())
 	if err != nil {
 		return err
 	}
 	if payload.Timestamp != uint64(t.Unix()) {
-		return errors.New("incorrect timestamp")
+		return ErrInvalidPayloadTimeStamp
 	}
 	return nil
 }
@@ -220,7 +226,7 @@ func PayloadToHeader(payload *enginev1.ExecutionPayload) (*ethpb.ExecutionPayloa
 		ParentHash:       bytesutil.SafeCopyBytes(payload.ParentHash),
 		FeeRecipient:     bytesutil.SafeCopyBytes(payload.FeeRecipient),
 		StateRoot:        bytesutil.SafeCopyBytes(payload.StateRoot),
-		ReceiptRoot:      bytesutil.SafeCopyBytes(payload.ReceiptsRoot),
+		ReceiptsRoot:     bytesutil.SafeCopyBytes(payload.ReceiptsRoot),
 		LogsBloom:        bytesutil.SafeCopyBytes(payload.LogsBloom),
 		PrevRandao:       bytesutil.SafeCopyBytes(payload.PrevRandao),
 		BlockNumber:      payload.BlockNumber,
@@ -234,7 +240,7 @@ func PayloadToHeader(payload *enginev1.ExecutionPayload) (*ethpb.ExecutionPayloa
 	}, nil
 }
 
-func isEmptyPayload(p *enginev1.ExecutionPayload) bool {
+func IsEmptyPayload(p *enginev1.ExecutionPayload) bool {
 	if p == nil {
 		return true
 	}
@@ -293,7 +299,7 @@ func isEmptyHeader(h *ethpb.ExecutionPayloadHeader) bool {
 	if !bytes.Equal(h.StateRoot, make([]byte, fieldparams.RootLength)) {
 		return false
 	}
-	if !bytes.Equal(h.ReceiptRoot, make([]byte, fieldparams.RootLength)) {
+	if !bytes.Equal(h.ReceiptsRoot, make([]byte, fieldparams.RootLength)) {
 		return false
 	}
 	if !bytes.Equal(h.LogsBloom, make([]byte, fieldparams.LogsBloomLength)) {
@@ -328,3 +334,62 @@ func isEmptyHeader(h *ethpb.ExecutionPayloadHeader) bool {
 	}
 	return true
 }
+
+// ValidatePayloadHeaderWhenMergeCompletes validates the payload header when the merge completes.
+func ValidatePayloadHeaderWhenMergeCompletes(st state.BeaconState, header *ethpb.ExecutionPayloadHeader) error {
+	// Skip validation if the state is not merge compatible.
+	complete, err := IsMergeTransitionComplete(st)
+	if err != nil {
+		return err
+	}
+	if !complete {
+		return nil
+	}
+	// Validate current header's parent hash matches state header's block hash.
+	h, err := st.LatestExecutionPayloadHeader()
+	if err != nil {
+		return err
+	}
+	if !bytes.Equal(header.ParentHash, h.BlockHash) {
+		return ErrInvalidPayloadBlockHash
+	}
+	return nil
+}
+
+// ValidatePayloadHeader validates the payload header.
+func ValidatePayloadHeader(st state.BeaconState, header *ethpb.ExecutionPayloadHeader) error {
+	// Validate header's random mix matches with state in current epoch
+	random, err := helpers.RandaoMix(st, time.CurrentEpoch(st))
+	if err != nil {
+		return err
+	}
+	if !bytes.Equal(header.PrevRandao, random) {
+		return ErrInvalidPayloadPrevRandao
+	}
+
+	// Validate header's timestamp matches with state in current slot.
+	t, err := slots.ToTime(st.GenesisTime(), st.Slot())
+	if err != nil {
+		return err
+	}
+	if header.Timestamp != uint64(t.Unix()) {
+		return ErrInvalidPayloadTimeStamp
+	}
+	return nil
+}
+
+// ProcessPayloadHeader processes the payload header.
+func ProcessPayloadHeader(st state.BeaconState, header *ethpb.ExecutionPayloadHeader) (state.BeaconState, error) {
+	if err := ValidatePayloadHeaderWhenMergeCompletes(st, header); err != nil {
+		return nil, err
+	}
+
+	if err := ValidatePayloadHeader(st, header); err != nil {
+		return nil, err
+	}
+
+	if err := st.SetLatestExecutionPayloadHeader(header); err != nil {
+		return nil, err
+	}
+	return st, nil
+}

beacon-chain/core/blocks/payload_test.go

@@ -7,6 +7,7 @@ import (
 	"github.com/prysmaticlabs/prysm/beacon-chain/core/blocks"
 	"github.com/prysmaticlabs/prysm/beacon-chain/core/helpers"
 	"github.com/prysmaticlabs/prysm/beacon-chain/core/time"
+	"github.com/prysmaticlabs/prysm/beacon-chain/state"
 	fieldparams "github.com/prysmaticlabs/prysm/config/fieldparams"
 	"github.com/prysmaticlabs/prysm/encoding/bytesutil"
 	"github.com/prysmaticlabs/prysm/encoding/ssz"
@@ -60,7 +61,7 @@ func Test_IsMergeComplete(t *testing.T) {
 			name: "has receipt root",
 			payload: func() *ethpb.ExecutionPayloadHeader {
 				h := emptyPayloadHeader()
-				h.ReceiptRoot = bytesutil.PadTo([]byte{'a'}, fieldparams.RootLength)
+				h.ReceiptsRoot = bytesutil.PadTo([]byte{'a'}, fieldparams.RootLength)
 				return h
 			}(),
 			want: true,
@@ -600,7 +601,7 @@ func Test_ValidatePayload(t *testing.T) {
 		{
 			name:    "incorrect prev randao",
 			payload: emptyPayload(),
-			err:     errors.New("incorrect prev randao"),
+			err:     blocks.ErrInvalidPayloadPrevRandao,
 		},
 		{
 			name: "incorrect timestamp",
@@ -610,7 +611,7 @@ func Test_ValidatePayload(t *testing.T) {
 				h.Timestamp = 1
 				return h
 			}(),
-			err: errors.New("incorrect timestamp"),
+			err: blocks.ErrInvalidPayloadTimeStamp,
 		},
 	}
 	for _, tt := range tests {
@@ -648,7 +649,7 @@ func Test_ProcessPayload(t *testing.T) {
 		{
 			name:    "incorrect prev randao",
 			payload: emptyPayload(),
-			err:     errors.New("incorrect prev randao"),
+			err:     blocks.ErrInvalidPayloadPrevRandao,
 		},
 		{
 			name: "incorrect timestamp",
@@ -658,7 +659,7 @@ func Test_ProcessPayload(t *testing.T) {
 				h.Timestamp = 1
 				return h
 			}(),
-			err: errors.New("incorrect timestamp"),
+			err: blocks.ErrInvalidPayloadTimeStamp,
 		},
 	}
 	for _, tt := range tests {
@@ -678,6 +679,149 @@ func Test_ProcessPayload(t *testing.T) {
 	}
 }
 
+func Test_ProcessPayloadHeader(t *testing.T) {
+	st, _ := util.DeterministicGenesisStateBellatrix(t, 1)
+	random, err := helpers.RandaoMix(st, time.CurrentEpoch(st))
+	require.NoError(t, err)
+	ts, err := slots.ToTime(st.GenesisTime(), st.Slot())
+	require.NoError(t, err)
+	tests := []struct {
+		name   string
+		header *ethpb.ExecutionPayloadHeader
+		err    error
+	}{
+		{
+			name: "process passes",
+			header: func() *ethpb.ExecutionPayloadHeader {
+				h := emptyPayloadHeader()
+				h.PrevRandao = random
+				h.Timestamp = uint64(ts.Unix())
+				return h
+			}(), err: nil,
+		},
+		{
+			name:   "incorrect prev randao",
+			header: emptyPayloadHeader(),
+			err:    blocks.ErrInvalidPayloadPrevRandao,
+		},
+		{
+			name: "incorrect timestamp",
+			header: func() *ethpb.ExecutionPayloadHeader {
+				h := emptyPayloadHeader()
+				h.PrevRandao = random
+				h.Timestamp = 1
+				return h
+			}(),
+			err: blocks.ErrInvalidPayloadTimeStamp,
+		},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			st, err := blocks.ProcessPayloadHeader(st, tt.header)
+			if err != nil {
+				require.Equal(t, tt.err.Error(), err.Error())
+			} else {
+				require.Equal(t, tt.err, err)
+				got, err := st.LatestExecutionPayloadHeader()
+				require.NoError(t, err)
+				require.DeepSSZEqual(t, tt.header, got)
+			}
+		})
+	}
+}
+
+func Test_ValidatePayloadHeader(t *testing.T) {
+	st, _ := util.DeterministicGenesisStateBellatrix(t, 1)
+	random, err := helpers.RandaoMix(st, time.CurrentEpoch(st))
+	require.NoError(t, err)
+	ts, err := slots.ToTime(st.GenesisTime(), st.Slot())
+	require.NoError(t, err)
+	tests := []struct {
+		name   string
+		header *ethpb.ExecutionPayloadHeader
+		err    error
+	}{
+		{
+			name: "process passes",
+			header: func() *ethpb.ExecutionPayloadHeader {
+				h := emptyPayloadHeader()
+				h.PrevRandao = random
+				h.Timestamp = uint64(ts.Unix())
+				return h
+			}(), err: nil,
+		},
+		{
+			name:   "incorrect prev randao",
+			header: emptyPayloadHeader(),
+			err:    blocks.ErrInvalidPayloadPrevRandao,
+		},
+		{
+			name: "incorrect timestamp",
+			header: func() *ethpb.ExecutionPayloadHeader {
+				h := emptyPayloadHeader()
+				h.PrevRandao = random
+				h.Timestamp = 1
+				return h
+			}(),
+			err: blocks.ErrInvalidPayloadTimeStamp,
+		},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			err := blocks.ValidatePayloadHeader(st, tt.header)
+			require.Equal(t, tt.err, err)
+		})
+	}
+}
+
+func Test_ValidatePayloadHeaderWhenMergeCompletes(t *testing.T) {
+	st, _ := util.DeterministicGenesisStateBellatrix(t, 1)
+	emptySt := st.Copy()
+	require.NoError(t, st.SetLatestExecutionPayloadHeader(&ethpb.ExecutionPayloadHeader{BlockHash: []byte{'a'}}))
+	tests := []struct {
+		name   string
+		state  state.BeaconState
+		header *ethpb.ExecutionPayloadHeader
+		err    error
+	}{
+		{
+			name: "no merge",
+			header: func() *ethpb.ExecutionPayloadHeader {
+				h := emptyPayloadHeader()
+				return h
+			}(),
+			state: emptySt,
+			err:   nil,
+		},
+		{
+			name: "process passes",
+			header: func() *ethpb.ExecutionPayloadHeader {
+				h := emptyPayloadHeader()
+				h.ParentHash = []byte{'a'}
+				return h
+			}(),
+			state: st,
+			err:   nil,
+		},
+		{
+			name: "invalid block hash",
+			header: func() *ethpb.ExecutionPayloadHeader {
+				h := emptyPayloadHeader()
+				h.ParentHash = []byte{'b'}
+				return h
+			}(),
+			state: st,
+			err:   blocks.ErrInvalidPayloadBlockHash,
+		},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			err := blocks.ValidatePayloadHeaderWhenMergeCompletes(tt.state, tt.header)
+			require.Equal(t, tt.err, err)
+		})
+	}
+}
+
 func Test_PayloadToHeader(t *testing.T) {
 	p := emptyPayload()
 	h, err := blocks.PayloadToHeader(p)
@@ -705,7 +849,7 @@ func Test_PayloadToHeader(t *testing.T) {
 	require.DeepSSZEqual(t, h.ParentHash, make([]byte, fieldparams.RootLength))
 	require.DeepSSZEqual(t, h.FeeRecipient, make([]byte, fieldparams.FeeRecipientLength))
 	require.DeepSSZEqual(t, h.StateRoot, make([]byte, fieldparams.RootLength))
-	require.DeepSSZEqual(t, h.ReceiptRoot, make([]byte, fieldparams.RootLength))
+	require.DeepSSZEqual(t, h.ReceiptsRoot, make([]byte, fieldparams.RootLength))
 	require.DeepSSZEqual(t, h.LogsBloom, make([]byte, fieldparams.LogsBloomLength))
 	require.DeepSSZEqual(t, h.PrevRandao, make([]byte, fieldparams.RootLength))
 	require.DeepSSZEqual(t, h.ExtraData, make([]byte, 0))
@@ -733,7 +877,7 @@ func emptyPayloadHeader() *ethpb.ExecutionPayloadHeader {
 		ParentHash:       make([]byte, fieldparams.RootLength),
 		FeeRecipient:     make([]byte, fieldparams.FeeRecipientLength),
 		StateRoot:        make([]byte, fieldparams.RootLength),
-		ReceiptRoot:      make([]byte, fieldparams.RootLength),
+		ReceiptsRoot:     make([]byte, fieldparams.RootLength),
 		LogsBloom:        make([]byte, fieldparams.LogsBloomLength),
 		PrevRandao:       make([]byte, fieldparams.RootLength),
 		BaseFeePerGas:    make([]byte, fieldparams.RootLength),

beacon-chain/core/blocks/proposer_slashing_regression_test.go

@@ -1,7 +1,7 @@
 package blocks_test
 
 import (
-	"io/ioutil"
+	"os"
 	"testing"
 
 	"github.com/prysmaticlabs/prysm/beacon-chain/core/blocks"
@@ -16,7 +16,7 @@ import (
 // when it was not in actuality.
 // See: https://github.com/sigp/beacon-fuzz/issues/91
 func TestVerifyProposerSlashing_BeaconFuzzIssue91(t *testing.T) {
-	file, err := ioutil.ReadFile("testdata/beaconfuzz_91_beacon.ssz")
+	file, err := os.ReadFile("testdata/beaconfuzz_91_beacon.ssz")
 	require.NoError(t, err)
 	rawState := &ethpb.BeaconState{}
 	err = rawState.UnmarshalSSZ(file)
@@ -25,7 +25,7 @@ func TestVerifyProposerSlashing_BeaconFuzzIssue91(t *testing.T) {
 	st, err := v1.InitializeFromProtoUnsafe(rawState)
 	require.NoError(t, err)
 
-	file, err = ioutil.ReadFile("testdata/beaconfuzz_91_proposer_slashing.ssz")
+	file, err = os.ReadFile("testdata/beaconfuzz_91_proposer_slashing.ssz")
 	require.NoError(t, err)
 	slashing := &ethpb.ProposerSlashing{}
 	err = slashing.UnmarshalSSZ(file)

beacon-chain/core/epoch/BUILD.bazel

@@ -13,7 +13,6 @@ go_library(
         "//beacon-chain/core/time:go_default_library",
         "//beacon-chain/core/validators:go_default_library",
         "//beacon-chain/state:go_default_library",
-        "//config/features:go_default_library",
         "//config/params:go_default_library",
         "//math:go_default_library",
         "//proto/prysm/v1alpha1:go_default_library",

beacon-chain/core/epoch/epoch_processing.go

@@ -15,7 +15,6 @@ import (
 	"github.com/prysmaticlabs/prysm/beacon-chain/core/time"
 	"github.com/prysmaticlabs/prysm/beacon-chain/core/validators"
 	"github.com/prysmaticlabs/prysm/beacon-chain/state"
-	"github.com/prysmaticlabs/prysm/config/features"
 	"github.com/prysmaticlabs/prysm/config/params"
 	"github.com/prysmaticlabs/prysm/math"
 	ethpb "github.com/prysmaticlabs/prysm/proto/prysm/v1alpha1"
@@ -250,6 +249,7 @@ func ProcessEffectiveBalanceUpdates(state state.BeaconState) (state.BeaconState,
 	upwardThreshold := hysteresisInc * params.BeaconConfig().HysteresisUpwardMultiplier
 
 	bals := state.Balances()
+
 	// Update effective balances with hysteresis.
 	validatorFunc := func(idx int, val *ethpb.Validator) (bool, *ethpb.Validator, error) {
 		if val == nil {
@@ -261,40 +261,18 @@ func ProcessEffectiveBalanceUpdates(state state.BeaconState) (state.BeaconState,
 		balance := bals[idx]
 
 		if balance+downwardThreshold < val.EffectiveBalance || val.EffectiveBalance+upwardThreshold < balance {
-			newVal := ethpb.CopyValidator(val)
-			newVal.EffectiveBalance = maxEffBalance
-			if newVal.EffectiveBalance > balance-balance%effBalanceInc {
-				newVal.EffectiveBalance = balance - balance%effBalanceInc
+			effectiveBal := maxEffBalance
+			if effectiveBal > balance-balance%effBalanceInc {
+				effectiveBal = balance - balance%effBalanceInc
 			}
-			return true, newVal, nil
-		}
-		return false, val, nil
-	}
-
-	if features.Get().EnableOptimizedBalanceUpdate {
-		validatorFunc = func(idx int, val *ethpb.Validator) (bool, *ethpb.Validator, error) {
-			if val == nil {
-				return false, nil, fmt.Errorf("validator %d is nil in state", idx)
-			}
-			if idx >= len(bals) {
-				return false, nil, fmt.Errorf("validator index exceeds validator length in state %d >= %d", idx, len(state.Balances()))
-			}
-			balance := bals[idx]
-
-			if balance+downwardThreshold < val.EffectiveBalance || val.EffectiveBalance+upwardThreshold < balance {
-				effectiveBal := maxEffBalance
-				if effectiveBal > balance-balance%effBalanceInc {
-					effectiveBal = balance - balance%effBalanceInc
-				}
-				if effectiveBal != val.EffectiveBalance {
-					newVal := ethpb.CopyValidator(val)
-					newVal.EffectiveBalance = effectiveBal
-					return true, newVal, nil
-				}
-				return false, val, nil
+			if effectiveBal != val.EffectiveBalance {
+				newVal := ethpb.CopyValidator(val)
+				newVal.EffectiveBalance = effectiveBal
+				return true, newVal, nil
 			}
 			return false, val, nil
 		}
+		return false, val, nil
 	}
 
 	if err := state.ApplyToEveryValidator(validatorFunc); err != nil {

beacon-chain/core/execution/upgrade.go

@@ -69,7 +69,7 @@ func UpgradeToBellatrix(ctx context.Context, state state.BeaconState) (state.Bea
 			ParentHash:       make([]byte, 32),
 			FeeRecipient:     make([]byte, 20),
 			StateRoot:        make([]byte, 32),
-			ReceiptRoot:      make([]byte, 32),
+			ReceiptsRoot:     make([]byte, 32),
 			LogsBloom:        make([]byte, 256),
 			PrevRandao:       make([]byte, 32),
 			BlockNumber:      0,

beacon-chain/core/execution/upgrade_test.go

@@ -65,7 +65,7 @@ func TestUpgradeToBellatrix(t *testing.T) {
 		ParentHash:       make([]byte, 32),
 		FeeRecipient:     make([]byte, 20),
 		StateRoot:        make([]byte, 32),
-		ReceiptRoot:      make([]byte, 32),
+		ReceiptsRoot:     make([]byte, 32),
 		LogsBloom:        make([]byte, 256),
 		PrevRandao:       make([]byte, 32),
 		BlockNumber:      0,

beacon-chain/core/helpers/BUILD.bazel

@@ -63,7 +63,6 @@ go_test(
         "//beacon-chain/state:go_default_library",
         "//beacon-chain/state/v1:go_default_library",
         "//beacon-chain/state/v2:go_default_library",
-        "//config/features:go_default_library",
         "//config/fieldparams:go_default_library",
         "//config/params:go_default_library",
         "//container/slice:go_default_library",

beacon-chain/core/helpers/beacon_committee.go

@@ -374,6 +374,7 @@ func ClearCache() {
 	committeeCache = cache.NewCommitteesCache()
 	proposerIndicesCache = cache.NewProposerIndicesCache()
 	syncCommitteeCache = cache.NewSyncCommittee()
+	balanceCache = cache.NewEffectiveBalanceCache()
 }
 
 // computeCommittee returns the requested shuffled committee out of the total committees using

beacon-chain/core/helpers/rewards_penalties_test.go

@@ -7,7 +7,6 @@ import (
 	types "github.com/prysmaticlabs/eth2-types"
 	"github.com/prysmaticlabs/prysm/beacon-chain/core/time"
 	v1 "github.com/prysmaticlabs/prysm/beacon-chain/state/v1"
-	"github.com/prysmaticlabs/prysm/config/features"
 	"github.com/prysmaticlabs/prysm/config/params"
 	ethpb "github.com/prysmaticlabs/prysm/proto/prysm/v1alpha1"
 	"github.com/prysmaticlabs/prysm/testing/assert"
@@ -76,11 +75,6 @@ func TestTotalActiveBalance(t *testing.T) {
 }
 
 func TestTotalActiveBalance_WithCache(t *testing.T) {
-	resetCfg := features.InitWithReset(&features.Flags{
-		EnableActiveBalanceCache: true,
-	})
-	defer resetCfg()
-
 	tests := []struct {
 		vCount    int
 		wantCount int

beacon-chain/core/helpers/sync_committee.go

@@ -11,6 +11,7 @@ import (
 	"github.com/prysmaticlabs/prysm/beacon-chain/core/time"
 	"github.com/prysmaticlabs/prysm/beacon-chain/state"
 	"github.com/prysmaticlabs/prysm/config/params"
+	"github.com/prysmaticlabs/prysm/crypto/hash"
 	"github.com/prysmaticlabs/prysm/encoding/bytesutil"
 	"github.com/prysmaticlabs/prysm/time/slots"
 	log "github.com/sirupsen/logrus"
@@ -31,7 +32,7 @@ func IsCurrentPeriodSyncCommittee(
 	if err != nil {
 		return false, err
 	}
-	indices, err := syncCommitteeCache.CurrentPeriodIndexPosition(bytesutil.ToBytes32(root), valIdx)
+	indices, err := syncCommitteeCache.CurrentPeriodIndexPosition(root, valIdx)
 	if err == cache.ErrNonExistingSyncCommitteeKey {
 		val, err := st.ValidatorAtIndex(valIdx)
 		if err != nil {
@@ -44,7 +45,7 @@ func IsCurrentPeriodSyncCommittee(
 
 		// Fill in the cache on miss.
 		go func() {
-			if err := syncCommitteeCache.UpdatePositionsInCommittee(bytesutil.ToBytes32(root), st); err != nil {
+			if err := syncCommitteeCache.UpdatePositionsInCommittee(root, st); err != nil {
 				log.Errorf("Could not fill sync committee cache on miss: %v", err)
 			}
 		}()
@@ -68,7 +69,7 @@ func IsNextPeriodSyncCommittee(
 	if err != nil {
 		return false, err
 	}
-	indices, err := syncCommitteeCache.NextPeriodIndexPosition(bytesutil.ToBytes32(root), valIdx)
+	indices, err := syncCommitteeCache.NextPeriodIndexPosition(root, valIdx)
 	if err == cache.ErrNonExistingSyncCommitteeKey {
 		val, err := st.ValidatorAtIndex(valIdx)
 		if err != nil {
@@ -95,7 +96,7 @@ func CurrentPeriodSyncSubcommitteeIndices(
 	if err != nil {
 		return nil, err
 	}
-	indices, err := syncCommitteeCache.CurrentPeriodIndexPosition(bytesutil.ToBytes32(root), valIdx)
+	indices, err := syncCommitteeCache.CurrentPeriodIndexPosition(root, valIdx)
 	if err == cache.ErrNonExistingSyncCommitteeKey {
 		val, err := st.ValidatorAtIndex(valIdx)
 		if err != nil {
@@ -108,7 +109,7 @@ func CurrentPeriodSyncSubcommitteeIndices(
 
 		// Fill in the cache on miss.
 		go func() {
-			if err := syncCommitteeCache.UpdatePositionsInCommittee(bytesutil.ToBytes32(root), st); err != nil {
+			if err := syncCommitteeCache.UpdatePositionsInCommittee(root, st); err != nil {
 				log.Errorf("Could not fill sync committee cache on miss: %v", err)
 			}
 		}()
@@ -129,7 +130,7 @@ func NextPeriodSyncSubcommitteeIndices(
 	if err != nil {
 		return nil, err
 	}
-	indices, err := syncCommitteeCache.NextPeriodIndexPosition(bytesutil.ToBytes32(root), valIdx)
+	indices, err := syncCommitteeCache.NextPeriodIndexPosition(root, valIdx)
 	if err == cache.ErrNonExistingSyncCommitteeKey {
 		val, err := st.ValidatorAtIndex(valIdx)
 		if err != nil {
@@ -169,7 +170,7 @@ func UpdateSyncCommitteeCache(st state.BeaconStateAltair) error {
 		return err
 	}
 
-	return syncCommitteeCache.UpdatePositionsInCommittee(prevBlockRoot, st)
+	return syncCommitteeCache.UpdatePositionsInCommittee(combineRootAndSlot(prevBlockRoot[:], uint64(header.Slot)), st)
 }
 
 // Loop through `pubKeys` for matching `pubKey` and get the indices where it matches.
@@ -186,19 +187,19 @@ func findSubCommitteeIndices(pubKey []byte, pubKeys [][]byte) []types.CommitteeI
 // Retrieve the current sync period boundary root by calculating sync period start epoch
 // and calling `BlockRoot`.
 // It uses the boundary slot - 1 for block root. (Ex: SlotsPerEpoch * EpochsPerSyncCommitteePeriod - 1)
-func syncPeriodBoundaryRoot(st state.ReadOnlyBeaconState) ([]byte, error) {
+func syncPeriodBoundaryRoot(st state.ReadOnlyBeaconState) ([32]byte, error) {
 	// Can't call `BlockRoot` until the first slot.
 	if st.Slot() == params.BeaconConfig().GenesisSlot {
-		return params.BeaconConfig().ZeroHash[:], nil
+		return params.BeaconConfig().ZeroHash, nil
 	}
 
 	startEpoch, err := slots.SyncCommitteePeriodStartEpoch(time.CurrentEpoch(st))
 	if err != nil {
-		return nil, err
+		return [32]byte{}, err
 	}
 	startEpochSlot, err := slots.EpochStart(startEpoch)
 	if err != nil {
-		return nil, err
+		return [32]byte{}, err
 	}
 
 	// Prevent underflow
@@ -206,5 +207,15 @@ func syncPeriodBoundaryRoot(st state.ReadOnlyBeaconState) ([]byte, error) {
 		startEpochSlot--
 	}
 
-	return BlockRootAtSlot(st, startEpochSlot)
+	root, err := BlockRootAtSlot(st, startEpochSlot)
+	if err != nil {
+		return [32]byte{}, err
+	}
+	return combineRootAndSlot(root, uint64(startEpochSlot)), nil
+}
+
+func combineRootAndSlot(root []byte, slot uint64) [32]byte {
+	slotBytes := bytesutil.Uint64ToBytesLittleEndian(slot)
+	keyHash := hash.Hash(append(root, slotBytes...))
+	return keyHash
 }

beacon-chain/core/helpers/sync_committee_test.go

@@ -1,6 +1,7 @@
 package helpers
 
 import (
+	"math/rand"
 	"strconv"
 	"testing"
 	"time"
@@ -12,6 +13,7 @@ import (
 	"github.com/prysmaticlabs/prysm/config/params"
 	"github.com/prysmaticlabs/prysm/encoding/bytesutil"
 	ethpb "github.com/prysmaticlabs/prysm/proto/prysm/v1alpha1"
+	"github.com/prysmaticlabs/prysm/testing/assert"
 	"github.com/prysmaticlabs/prysm/testing/require"
 )
 
@@ -234,7 +236,7 @@ func TestCurrentEpochSyncSubcommitteeIndices_UsingCommittee(t *testing.T) {
 	require.NoError(t, err)
 
 	// Test that cache was empty.
-	_, err = syncCommitteeCache.CurrentPeriodIndexPosition(bytesutil.ToBytes32(root), 0)
+	_, err = syncCommitteeCache.CurrentPeriodIndexPosition(root, 0)
 	require.Equal(t, cache.ErrNonExistingSyncCommitteeKey, err)
 
 	// Test that helper can retrieve the index given empty cache.
@@ -244,7 +246,7 @@ func TestCurrentEpochSyncSubcommitteeIndices_UsingCommittee(t *testing.T) {
 
 	// Test that cache was able to fill on miss.
 	time.Sleep(100 * time.Millisecond)
-	index, err = syncCommitteeCache.CurrentPeriodIndexPosition(bytesutil.ToBytes32(root), 0)
+	index, err = syncCommitteeCache.CurrentPeriodIndexPosition(root, 0)
 	require.NoError(t, err)
 	require.DeepEqual(t, []types.CommitteeIndex{0}, index)
 }
@@ -384,3 +386,46 @@ func TestUpdateSyncCommitteeCache_BadRoot(t *testing.T) {
 	err = UpdateSyncCommitteeCache(state)
 	require.ErrorContains(t, "zero hash state root can't be used to update cache", err)
 }
+
+func TestIsCurrentEpochSyncCommittee_SameBlockRoot(t *testing.T) {
+	validators := make([]*ethpb.Validator, params.BeaconConfig().SyncCommitteeSize)
+	syncCommittee := &ethpb.SyncCommittee{
+		AggregatePubkey: bytesutil.PadTo([]byte{}, params.BeaconConfig().BLSPubkeyLength),
+	}
+	for i := 0; i < len(validators); i++ {
+		k := make([]byte, 48)
+		copy(k, strconv.Itoa(i))
+		validators[i] = &ethpb.Validator{
+			PublicKey: k,
+		}
+		syncCommittee.Pubkeys = append(syncCommittee.Pubkeys, bytesutil.PadTo(k, 48))
+	}
+
+	blockRoots := make([][]byte, params.BeaconConfig().SlotsPerHistoricalRoot)
+	for i := range blockRoots {
+		blockRoots[i] = make([]byte, 32)
+	}
+	state, err := v2.InitializeFromProto(&ethpb.BeaconStateAltair{
+		Validators: validators,
+		BlockRoots: blockRoots,
+	})
+	require.NoError(t, err)
+	require.NoError(t, state.SetCurrentSyncCommittee(syncCommittee))
+	require.NoError(t, state.SetNextSyncCommittee(syncCommittee))
+
+	ClearCache()
+	comIdxs, err := CurrentPeriodSyncSubcommitteeIndices(state, 200)
+	require.NoError(t, err)
+
+	wantedSlot := params.BeaconConfig().EpochsPerSyncCommitteePeriod.Mul(uint64(params.BeaconConfig().SlotsPerEpoch))
+	assert.NoError(t, state.SetSlot(types.Slot(wantedSlot)))
+	syncCommittee, err = state.CurrentSyncCommittee()
+	assert.NoError(t, err)
+	rand.Shuffle(len(syncCommittee.Pubkeys), func(i, j int) {
+		syncCommittee.Pubkeys[i], syncCommittee.Pubkeys[j] = syncCommittee.Pubkeys[j], syncCommittee.Pubkeys[i]
+	})
+	require.NoError(t, state.SetCurrentSyncCommittee(syncCommittee))
+	newIdxs, err := CurrentPeriodSyncSubcommitteeIndices(state, 200)
+	require.NoError(t, err)
+	require.DeepNotEqual(t, comIdxs, newIdxs)
+}

beacon-chain/core/transition/transition_no_verify_sig.go

@@ -290,13 +290,24 @@ func ProcessBlockForStateRoot(
 		return nil, errors.Wrap(err, "could not check if execution is enabled")
 	}
 	if enabled {
-		payload, err := blk.Body().ExecutionPayload()
-		if err != nil {
-			return nil, err
-		}
-		state, err = b.ProcessPayload(state, payload)
-		if err != nil {
-			return nil, errors.Wrap(err, "could not process execution payload")
+		if blk.IsBlinded() {
+			header, err := blk.Body().ExecutionPayloadHeader()
+			if err != nil {
+				return nil, err
+			}
+			state, err = b.ProcessPayloadHeader(state, header)
+			if err != nil {
+				return nil, errors.Wrap(err, "could not process execution payload header")
+			}
+		} else {
+			payload, err := blk.Body().ExecutionPayload()
+			if err != nil {
+				return nil, err
+			}
+			state, err = b.ProcessPayload(state, payload)
+			if err != nil {
+				return nil, errors.Wrap(err, "could not process execution payload")
+			}
 		}
 	}
 

beacon-chain/db/kv/backup_test.go

@@ -2,7 +2,6 @@ package kv
 
 import (
 	"context"
-	"io/ioutil"
 	"os"
 	"path/filepath"
 	"testing"
@@ -34,7 +33,7 @@ func TestStore_Backup(t *testing.T) {
 	require.NoError(t, db.Backup(ctx, "", false))
 
 	backupsPath := filepath.Join(db.databasePath, backupsDirectoryName)
-	files, err := ioutil.ReadDir(backupsPath)
+	files, err := os.ReadDir(backupsPath)
 	require.NoError(t, err)
 	require.NotEqual(t, 0, len(files), "No backups created")
 	require.NoError(t, db.Close(), "Failed to close database")
@@ -78,7 +77,7 @@ func TestStore_BackupMultipleBuckets(t *testing.T) {
 	require.NoError(t, db.Backup(ctx, "", false))
 
 	backupsPath := filepath.Join(db.databasePath, backupsDirectoryName)
-	files, err := ioutil.ReadDir(backupsPath)
+	files, err := os.ReadDir(backupsPath)
 	require.NoError(t, err)
 	require.NotEqual(t, 0, len(files), "No backups created")
 	require.NoError(t, db.Close(), "Failed to close database")

beacon-chain/db/kv/migration_state_validators.go

@@ -18,7 +18,7 @@ const batchSize = 10
 
 var migrationStateValidatorsKey = []byte("migration_state_validator")
 
-func migrateStateValidators(ctx context.Context, db *bolt.DB) error {
+func shouldMigrateValidators(db *bolt.DB) (bool, error) {
 	migrateDB := false
 	if updateErr := db.View(func(tx *bolt.Tx) error {
 		mb := tx.Bucket(migrationsBucket)
@@ -46,11 +46,17 @@ func migrateStateValidators(ctx context.Context, db *bolt.DB) error {
 		return nil
 	}); updateErr != nil {
 		log.WithError(updateErr).Errorf("could not migrate bucket: %s", stateBucket)
-		return updateErr
+		return false, updateErr
 	}
 
-	// do not migrate the DB
-	if !migrateDB {
+	return migrateDB, nil
+}
+
+func migrateStateValidators(ctx context.Context, db *bolt.DB) error {
+	if ok, err := shouldMigrateValidators(db); err != nil {
+		return err
+	} else if !ok {
+		// A migration is not required.
 		return nil
 	}
 

beacon-chain/db/kv/state.go

@@ -151,6 +151,10 @@ func (s *Store) SaveStates(ctx context.Context, states []state.ReadOnlyBeaconSta
 	})
 }
 
+type withValidators interface {
+	GetValidators() []*ethpb.Validator
+}
+
 // SaveStatesEfficient stores multiple states to the db (new schema) using the provided corresponding roots.
 func (s *Store) SaveStatesEfficient(ctx context.Context, states []state.ReadOnlyBeaconState, blockRoots [][32]byte) error {
 	ctx, span := trace.StartSpan(ctx, "BeaconDB.SaveStatesEfficient")
@@ -161,29 +165,12 @@ func (s *Store) SaveStatesEfficient(ctx context.Context, states []state.ReadOnly
 	validatorsEntries := make(map[string]*ethpb.Validator) // It's a map to make sure that you store only new validator entries.
 	validatorKeys := make([][]byte, len(states))           // For every state, this stores a compressed list of validator keys.
 	for i, st := range states {
-		var validators []*ethpb.Validator
-		switch st.InnerStateUnsafe().(type) {
-		case *ethpb.BeaconState:
-			pbState, err := v1.ProtobufBeaconState(st.InnerStateUnsafe())
-			if err != nil {
-				return err
-			}
-			validators = pbState.Validators
-		case *ethpb.BeaconStateAltair:
-			pbState, err := v2.ProtobufBeaconState(st.InnerStateUnsafe())
-			if err != nil {
-				return err
-			}
-			validators = pbState.Validators
-		case *ethpb.BeaconStateBellatrix:
-			pbState, err := v3.ProtobufBeaconState(st.InnerStateUnsafe())
-			if err != nil {
-				return err
-			}
-			validators = pbState.Validators
-		default:
-			return errors.New("invalid state type")
+		pb, ok := st.InnerStateUnsafe().(withValidators)
+		if !ok {
+			return errors.New("could not cast state to interface with GetValidators()")
 		}
+		validators := pb.GetValidators()
+
 		// yank out the validators and store them in separate table to save space.
 		var hashes []byte
 		for _, val := range validators {

beacon-chain/db/restore_test.go

@@ -3,7 +3,6 @@ package db
 import (
 	"context"
 	"flag"
-	"io/ioutil"
 	"os"
 	"path"
 	"testing"
@@ -55,7 +54,7 @@ func TestRestore(t *testing.T) {
 
 	assert.NoError(t, Restore(cliCtx))
 
-	files, err := ioutil.ReadDir(path.Join(restoreDir, kv.BeaconNodeDbDirName))
+	files, err := os.ReadDir(path.Join(restoreDir, kv.BeaconNodeDbDirName))
 	require.NoError(t, err)
 	assert.Equal(t, 1, len(files))
 	assert.Equal(t, kv.DatabaseFileName, files[0].Name())

beacon-chain/db/slasherkv/slasherkv_test.go

@@ -1,7 +1,7 @@
 package slasherkv
 
 import (
-	"io/ioutil"
+	"io"
 	"testing"
 
 	"github.com/sirupsen/logrus"
@@ -9,6 +9,6 @@ import (
 
 func TestMain(m *testing.M) {
 	logrus.SetLevel(logrus.DebugLevel)
-	logrus.SetOutput(ioutil.Discard)
+	logrus.SetOutput(io.Discard)
 	m.Run()
 }

beacon-chain/deterministic-genesis/service.go

@@ -5,8 +5,8 @@ package interopcoldstart
 
 import (
 	"context"
-	"io/ioutil"
 	"math/big"
+	"os"
 	"time"
 
 	types "github.com/prysmaticlabs/eth2-types"
@@ -47,17 +47,21 @@ type Config struct {
 // into the beacon chain database and running services at start up. This service should not be used in production
 // as it does not have any value other than ease of use for testing purposes.
 func NewService(ctx context.Context, cfg *Config) *Service {
-	log.Warn("Saving generated genesis state in database for interop testing")
 	ctx, cancel := context.WithCancel(ctx)
 
-	s := &Service{
+	return &Service{
 		cfg:    cfg,
 		ctx:    ctx,
 		cancel: cancel,
 	}
+}
+
+// Start initializes the genesis state from configured flags.
+func (s *Service) Start() {
+	log.Warn("Saving generated genesis state in database for interop testing")
 
 	if s.cfg.GenesisPath != "" {
-		data, err := ioutil.ReadFile(s.cfg.GenesisPath)
+		data, err := os.ReadFile(s.cfg.GenesisPath)
 		if err != nil {
 			log.Fatalf("Could not read pre-loaded state: %v", err)
 		}
@@ -69,14 +73,14 @@ func NewService(ctx context.Context, cfg *Config) *Service {
 		if err != nil {
 			log.Fatalf("Could not get state trie: %v", err)
 		}
-		if err := s.saveGenesisState(ctx, genesisTrie); err != nil {
+		if err := s.saveGenesisState(s.ctx, genesisTrie); err != nil {
 			log.Fatalf("Could not save interop genesis state %v", err)
 		}
-		return s
+		return
 	}
 
 	// Save genesis state in db
-	genesisState, _, err := interop.GenerateGenesisState(ctx, s.cfg.GenesisTime, s.cfg.NumValidators)
+	genesisState, _, err := interop.GenerateGenesisState(s.ctx, s.cfg.GenesisTime, s.cfg.NumValidators)
 	if err != nil {
 		log.Fatalf("Could not generate interop genesis state: %v", err)
 	}
@@ -92,17 +96,11 @@ func NewService(ctx context.Context, cfg *Config) *Service {
 	if err != nil {
 		log.Fatalf("Could not hash tree root genesis state: %v", err)
 	}
-	go slots.CountdownToGenesis(ctx, time.Unix(int64(s.cfg.GenesisTime), 0), s.cfg.NumValidators, gRoot)
+	go slots.CountdownToGenesis(s.ctx, time.Unix(int64(s.cfg.GenesisTime), 0), s.cfg.NumValidators, gRoot)
 
-	if err := s.saveGenesisState(ctx, genesisTrie); err != nil {
+	if err := s.saveGenesisState(s.ctx, genesisTrie); err != nil {
 		log.Fatalf("Could not save interop genesis state %v", err)
 	}
-
-	return s
-}
-
-// Start initializes the genesis state from configured flags.
-func (_ *Service) Start() {
 }
 
 // Stop does nothing.
@@ -155,7 +153,7 @@ func (_ *Service) FinalizedDeposits(_ context.Context) *depositcache.FinalizedDe
 }
 
 // NonFinalizedDeposits mocks out the deposit cache functionality for interop.
-func (_ *Service) NonFinalizedDeposits(_ context.Context, _ *big.Int) []*ethpb.Deposit {
+func (_ *Service) NonFinalizedDeposits(_ context.Context, _ int64, _ *big.Int) []*ethpb.Deposit {
 	return []*ethpb.Deposit{}
 }
 

beacon-chain/forkchoice/doubly-linked-tree/metrics.go

@@ -51,10 +51,4 @@ var (
 			Help: "The number of times pruning happened.",
 		},
 	)
-	validatedCount = promauto.NewGauge(
-		prometheus.GaugeOpts{
-			Name: "doublylinkedtree_validated_count",
-			Help: "The number of blocks that have been fully validated.",
-		},
-	)
 )

beacon-chain/forkchoice/doubly-linked-tree/node.go

@@ -120,7 +120,6 @@ func (n *Node) setNodeAndParentValidated(ctx context.Context) error {
 	}
 
 	n.optimistic = false
-	validatedCount.Inc()
 	return n.parent.setNodeAndParentValidated(ctx)
 }
 

beacon-chain/forkchoice/protoarray/metrics.go

@@ -51,10 +51,4 @@ var (
 			Help: "The number of times pruning happened.",
 		},
 	)
-	validatedNodesCount = promauto.NewCounter(
-		prometheus.CounterOpts{
-			Name: "proto_array_validated_nodes_count",
-			Help: "The number of nodes that have been fully validated.",
-		},
-	)
 )

beacon-chain/forkchoice/protoarray/optimistic_sync.go

@@ -43,7 +43,6 @@ func (f *ForkChoice) SetOptimisticToValid(ctx context.Context, root [32]byte) er
 		if index == NonExistentNode {
 			break
 		}
-		validatedNodesCount.Inc()
 	}
 	return nil
 }

beacon-chain/forkchoice/protoarray/store.go

@@ -614,16 +614,22 @@ func (s *Store) prune(ctx context.Context, finalizedRoot [32]byte) error {
 		node := copyNode(s.nodes[idx])
 		parentIdx, ok := canonicalNodesMap[node.parent]
 		if ok {
-			s.nodesIndices[node.root] = uint64(len(canonicalNodes))
-			canonicalNodesMap[idx] = uint64(len(canonicalNodes))
+			currentIndex := uint64(len(canonicalNodes))
+			s.nodesIndices[node.root] = currentIndex
+			s.payloadIndices[node.payloadHash] = currentIndex
+			canonicalNodesMap[idx] = currentIndex
 			node.parent = parentIdx
 			canonicalNodes = append(canonicalNodes, node)
 		} else {
-			// Remove node and synced tip that is not part of finalized branch.
+			// Remove node that is not part of finalized branch.
 			delete(s.nodesIndices, node.root)
+			delete(s.canonicalNodes, node.root)
+			delete(s.payloadIndices, node.payloadHash)
 		}
 	}
 	s.nodesIndices[finalizedRoot] = uint64(0)
+	s.canonicalNodes[finalizedRoot] = true
+	s.payloadIndices[finalizedNode.payloadHash] = uint64(0)
 
 	// Recompute the best child and descendant for each canonical nodes.
 	for _, node := range canonicalNodes {

beacon-chain/forkchoice/protoarray/store_test.go

@@ -375,7 +375,7 @@ func TestStore_Prune_MoreThanThreshold(t *testing.T) {
 		parent:         uint64(numOfNodes - 2),
 	})
 	indices[indexToHash(uint64(numOfNodes-1))] = uint64(numOfNodes - 1)
-	s := &Store{nodes: nodes, nodesIndices: indices}
+	s := &Store{nodes: nodes, nodesIndices: indices, canonicalNodes: map[[32]byte]bool{}, payloadIndices: map[[32]byte]uint64{}}
 
 	// Finalized root is at index 99 so everything before 99 should be pruned.
 	require.NoError(t, s.prune(context.Background(), indexToHash(99)))
@@ -413,7 +413,7 @@ func TestStore_Prune_MoreThanOnce(t *testing.T) {
 		parent:         uint64(numOfNodes - 2),
 	})
 
-	s := &Store{nodes: nodes, nodesIndices: indices}
+	s := &Store{nodes: nodes, nodesIndices: indices, canonicalNodes: map[[32]byte]bool{}, payloadIndices: map[[32]byte]uint64{}}
 
 	// Finalized root is at index 11 so everything before 11 should be pruned.
 	require.NoError(t, s.prune(context.Background(), indexToHash(10)))
@@ -441,6 +441,7 @@ func TestStore_Prune_NoDanglingBranch(t *testing.T) {
 			bestDescendant: 1,
 			root:           indexToHash(uint64(0)),
 			parent:         NonExistentNode,
+			payloadHash:    [32]byte{'A'},
 		},
 		{
 			slot:           101,
@@ -448,6 +449,7 @@ func TestStore_Prune_NoDanglingBranch(t *testing.T) {
 			bestChild:      NonExistentNode,
 			bestDescendant: NonExistentNode,
 			parent:         0,
+			payloadHash:    [32]byte{'B'},
 		},
 		{
 			slot:           101,
@@ -455,6 +457,7 @@ func TestStore_Prune_NoDanglingBranch(t *testing.T) {
 			parent:         0,
 			bestChild:      NonExistentNode,
 			bestDescendant: NonExistentNode,
+			payloadHash:    [32]byte{'C'},
 		},
 	}
 	s := &Store{
@@ -465,9 +468,22 @@ func TestStore_Prune_NoDanglingBranch(t *testing.T) {
 			indexToHash(uint64(1)): 1,
 			indexToHash(uint64(2)): 2,
 		},
+		canonicalNodes: map[[32]byte]bool{
+			indexToHash(uint64(0)): true,
+			indexToHash(uint64(1)): true,
+			indexToHash(uint64(2)): true,
+		},
+		payloadIndices: map[[32]byte]uint64{
+			[32]byte{'A'}: 0,
+			[32]byte{'B'}: 1,
+			[32]byte{'C'}: 2,
+		},
 	}
 	require.NoError(t, s.prune(context.Background(), indexToHash(uint64(1))))
-	require.Equal(t, len(s.nodes), 1)
+	require.Equal(t, 1, len(s.nodes))
+	require.Equal(t, 1, len(s.nodesIndices))
+	require.Equal(t, 1, len(s.canonicalNodes))
+	require.Equal(t, 1, len(s.payloadIndices))
 }
 
 // This test starts with the following branching diagram
@@ -482,25 +498,74 @@ func TestStore_Prune_NoDanglingBranch(t *testing.T) {
 //         J        -- K -- L
 //
 //
-func TestStore_PruneSyncedTips(t *testing.T) {
+func TestStore_PruneBranched(t *testing.T) {
 	ctx := context.Background()
-	f := setup(1, 1)
 
-	require.NoError(t, f.InsertOptimisticBlock(ctx, 100, [32]byte{'a'}, params.BeaconConfig().ZeroHash, params.BeaconConfig().ZeroHash, 1, 1))
-	require.NoError(t, f.InsertOptimisticBlock(ctx, 101, [32]byte{'b'}, [32]byte{'a'}, params.BeaconConfig().ZeroHash, 1, 1))
-	require.NoError(t, f.InsertOptimisticBlock(ctx, 102, [32]byte{'c'}, [32]byte{'b'}, params.BeaconConfig().ZeroHash, 1, 1))
-	require.NoError(t, f.InsertOptimisticBlock(ctx, 102, [32]byte{'j'}, [32]byte{'b'}, params.BeaconConfig().ZeroHash, 1, 1))
-	require.NoError(t, f.InsertOptimisticBlock(ctx, 103, [32]byte{'d'}, [32]byte{'c'}, params.BeaconConfig().ZeroHash, 1, 1))
-	require.NoError(t, f.InsertOptimisticBlock(ctx, 104, [32]byte{'e'}, [32]byte{'d'}, params.BeaconConfig().ZeroHash, 1, 1))
-	require.NoError(t, f.InsertOptimisticBlock(ctx, 104, [32]byte{'g'}, [32]byte{'d'}, params.BeaconConfig().ZeroHash, 1, 1))
-	require.NoError(t, f.InsertOptimisticBlock(ctx, 105, [32]byte{'f'}, [32]byte{'e'}, params.BeaconConfig().ZeroHash, 1, 1))
-	require.NoError(t, f.InsertOptimisticBlock(ctx, 105, [32]byte{'h'}, [32]byte{'g'}, params.BeaconConfig().ZeroHash, 1, 1))
-	require.NoError(t, f.InsertOptimisticBlock(ctx, 105, [32]byte{'k'}, [32]byte{'g'}, params.BeaconConfig().ZeroHash, 1, 1))
-	require.NoError(t, f.InsertOptimisticBlock(ctx, 106, [32]byte{'i'}, [32]byte{'h'}, params.BeaconConfig().ZeroHash, 1, 1))
-	require.NoError(t, f.InsertOptimisticBlock(ctx, 106, [32]byte{'l'}, [32]byte{'k'}, params.BeaconConfig().ZeroHash, 1, 1))
-	f.store.pruneThreshold = 0
-	require.NoError(t, f.Prune(ctx, [32]byte{'f'}))
-	require.Equal(t, 1, f.NodeCount())
+	tests := []struct {
+		finalizedRoot      [32]byte
+		wantedCanonical    [32]byte
+		wantedNonCanonical [32]byte
+		canonicalCount     int
+		payloadHash        [32]byte
+		payloadIndex       uint64
+		nonExistentPayload [32]byte
+	}{
+		{
+			[32]byte{'f'},
+			[32]byte{'f'},
+			[32]byte{'a'},
+			1,
+			[32]byte{'F'},
+			0,
+			[32]byte{'H'},
+		},
+		{
+			[32]byte{'d'},
+			[32]byte{'e'},
+			[32]byte{'i'},
+			3,
+			[32]byte{'E'},
+			1,
+			[32]byte{'C'},
+		},
+		{
+			[32]byte{'b'},
+			[32]byte{'f'},
+			[32]byte{'h'},
+			5,
+			[32]byte{'D'},
+			3,
+			[32]byte{'A'},
+		},
+	}
+
+	for _, tc := range tests {
+		f := setup(1, 1)
+		require.NoError(t, f.InsertOptimisticBlock(ctx, 100, [32]byte{'a'}, params.BeaconConfig().ZeroHash, [32]byte{'A'}, 1, 1))
+		require.NoError(t, f.InsertOptimisticBlock(ctx, 101, [32]byte{'b'}, [32]byte{'a'}, [32]byte{'B'}, 1, 1))
+		require.NoError(t, f.InsertOptimisticBlock(ctx, 102, [32]byte{'c'}, [32]byte{'b'}, [32]byte{'C'}, 1, 1))
+		require.NoError(t, f.InsertOptimisticBlock(ctx, 102, [32]byte{'j'}, [32]byte{'b'}, [32]byte{'J'}, 1, 1))
+		require.NoError(t, f.InsertOptimisticBlock(ctx, 103, [32]byte{'d'}, [32]byte{'c'}, [32]byte{'D'}, 1, 1))
+		require.NoError(t, f.InsertOptimisticBlock(ctx, 104, [32]byte{'e'}, [32]byte{'d'}, [32]byte{'E'}, 1, 1))
+		require.NoError(t, f.InsertOptimisticBlock(ctx, 104, [32]byte{'g'}, [32]byte{'d'}, [32]byte{'G'}, 1, 1))
+		require.NoError(t, f.InsertOptimisticBlock(ctx, 105, [32]byte{'f'}, [32]byte{'e'}, [32]byte{'F'}, 1, 1))
+		require.NoError(t, f.InsertOptimisticBlock(ctx, 105, [32]byte{'h'}, [32]byte{'g'}, [32]byte{'H'}, 1, 1))
+		require.NoError(t, f.InsertOptimisticBlock(ctx, 105, [32]byte{'k'}, [32]byte{'g'}, [32]byte{'K'}, 1, 1))
+		require.NoError(t, f.InsertOptimisticBlock(ctx, 106, [32]byte{'i'}, [32]byte{'h'}, [32]byte{'I'}, 1, 1))
+		require.NoError(t, f.InsertOptimisticBlock(ctx, 106, [32]byte{'l'}, [32]byte{'k'}, [32]byte{'L'}, 1, 1))
+		f.store.pruneThreshold = 0
+		require.NoError(t, f.store.updateCanonicalNodes(ctx, [32]byte{'f'}))
+		require.Equal(t, true, f.IsCanonical([32]byte{'a'}))
+		require.Equal(t, true, f.IsCanonical([32]byte{'f'}))
+
+		require.NoError(t, f.Prune(ctx, tc.finalizedRoot))
+		require.Equal(t, tc.canonicalCount, len(f.store.canonicalNodes))
+		require.Equal(t, true, f.IsCanonical(tc.wantedCanonical))
+		require.Equal(t, false, f.IsCanonical(tc.wantedNonCanonical))
+		require.Equal(t, tc.payloadIndex, f.store.payloadIndices[tc.payloadHash])
+		_, ok := f.store.payloadIndices[tc.nonExistentPayload]
+		require.Equal(t, false, ok)
+	}
 }
 
 func TestStore_LeadsToViableHead(t *testing.T) {

beacon-chain/monitor/service.go

@@ -95,6 +95,7 @@ func NewService(ctx context.Context, config *ValidatorMonitorConfig, tracked []t
 		latestPerformance:           make(map[types.ValidatorIndex]ValidatorLatestPerformance),
 		aggregatedPerformance:       make(map[types.ValidatorIndex]ValidatorAggregatedPerformance),
 		trackedSyncCommitteeIndices: make(map[types.ValidatorIndex][]types.CommitteeIndex),
+		isLogging:                   false,
 	}
 	for _, idx := range tracked {
 		r.TrackedValidators[idx] = true
@@ -117,7 +118,6 @@ func (s *Service) Start() {
 		"ValidatorIndices": tracked,
 	}).Info("Starting service")
 
-	s.isLogging = false
 	stateChannel := make(chan *feed.Event, 1)
 	stateSub := s.config.StateNotifier.StateFeed().Subscribe(stateChannel)
 

beacon-chain/node/node.go

@@ -906,6 +906,7 @@ func (b *BeaconNode) registerDeterminsticGenesisService() error {
 			DepositCache:  b.depositCache,
 			GenesisPath:   genesisStatePath,
 		})
+		svc.Start()
 
 		// Register genesis state as start-up state when interop mode.
 		// The start-up state gets reused across services.

beacon-chain/node/node_test.go

@@ -3,7 +3,6 @@ package node
 import (
 	"flag"
 	"fmt"
-	"os"
 	"path/filepath"
 	"testing"
 
@@ -41,7 +40,6 @@ func TestNodeClose_OK(t *testing.T) {
 	node.Close()
 
 	require.LogsContain(t, hook, "Stopping beacon node")
-	require.NoError(t, os.RemoveAll(tmp))
 }
 
 // TestClearDB tests clearing the database
@@ -67,5 +65,4 @@ func TestClearDB(t *testing.T) {
 	require.NoError(t, err)
 
 	require.LogsContain(t, hook, "Removing database")
-	require.NoError(t, os.RemoveAll(tmp))
 }

beacon-chain/node/registration/p2p.go

@@ -1,7 +1,7 @@
 package registration
 
 import (
-	"io/ioutil"
+	"os"
 	"path/filepath"
 
 	"github.com/prysmaticlabs/prysm/cmd"
@@ -42,7 +42,7 @@ func P2PPreregistration(cliCtx *cli.Context) (bootstrapNodeAddrs []string, dataD
 }
 
 func readbootNodes(fileName string) ([]string, error) {
-	fileContent, err := ioutil.ReadFile(fileName) // #nosec G304
+	fileContent, err := os.ReadFile(fileName) // #nosec G304
 	if err != nil {
 		return nil, err
 	}

beacon-chain/node/registration/p2p_test.go

@@ -2,7 +2,7 @@ package registration
 
 import (
 	"flag"
-	"io/ioutil"
+	"os"
 	"testing"
 
 	"github.com/prysmaticlabs/prysm/cmd"
@@ -27,9 +27,9 @@ func TestP2PPreregistration(t *testing.T) {
 	sampleNode := "- enr:-TESTNODE"
 	testDataDir := "testDataDir"
 
-	file, err := ioutil.TempFile(t.TempDir(), "bootstrapFile*.yaml")
+	file, err := os.CreateTemp(t.TempDir(), "bootstrapFile*.yaml")
 	require.NoError(t, err)
-	err = ioutil.WriteFile(file.Name(), []byte(sampleNode), 0644)
+	err = os.WriteFile(file.Name(), []byte(sampleNode), 0644)
 	require.NoError(t, err, "Error in WriteFile call")
 	params.SetupTestConfigCleanup(t)
 	config := params.BeaconNetworkConfig()
@@ -49,7 +49,7 @@ func TestP2PPreregistration(t *testing.T) {
 }
 
 func TestBootStrapNodeFile(t *testing.T) {
-	file, err := ioutil.TempFile(t.TempDir(), "bootstrapFile")
+	file, err := os.CreateTemp(t.TempDir(), "bootstrapFile")
 	require.NoError(t, err)
 
 	sampleNode0 := "- enr:-Ku4QMKVC_MowDsmEa20d5uGjrChI0h8_KsKXDmgVQbIbngZV0i" +
@@ -58,7 +58,7 @@ func TestBootStrapNodeFile(t *testing.T) {
 		"E1rtwzvGy40mq9eD66XfHPBWgIIN1ZHCCD6A"
 	sampleNode1 := "- enr:-TESTNODE2"
 	sampleNode2 := "- enr:-TESTNODE3"
-	err = ioutil.WriteFile(file.Name(), []byte(sampleNode0+"\n"+sampleNode1+"\n"+sampleNode2), 0644)
+	err = os.WriteFile(file.Name(), []byte(sampleNode0+"\n"+sampleNode1+"\n"+sampleNode2), 0644)
 	require.NoError(t, err, "Error in WriteFile call")
 	nodeList, err := readbootNodes(file.Name())
 	require.NoError(t, err, "Error in readbootNodes call")

beacon-chain/p2p/BUILD.bazel

@@ -127,6 +127,7 @@ go_test(
     ],
     embed = [":go_default_library"],
     flaky = True,
+    tags = ["requires-network"],
     deps = [
         "//async/event:go_default_library",
         "//beacon-chain/blockchain/testing:go_default_library",

beacon-chain/p2p/options_test.go

@@ -3,8 +3,8 @@ package p2p
 import (
 	"crypto/rand"
 	"encoding/hex"
-	"io/ioutil"
 	"net"
+	"os"
 	"testing"
 
 	gethCrypto "github.com/ethereum/go-ethereum/crypto"
@@ -17,7 +17,7 @@ import (
 )
 
 func TestPrivateKeyLoading(t *testing.T) {
-	file, err := ioutil.TempFile(t.TempDir(), "key")
+	file, err := os.CreateTemp(t.TempDir(), "key")
 	require.NoError(t, err)
 	key, _, err := crypto.GenerateSecp256k1Key(rand.Reader)
 	require.NoError(t, err, "Could not generate key")
@@ -27,7 +27,7 @@ func TestPrivateKeyLoading(t *testing.T) {
 	}
 	out := hex.EncodeToString(raw)
 
-	err = ioutil.WriteFile(file.Name(), []byte(out), params.BeaconIoConfig().ReadWritePermissions)
+	err = os.WriteFile(file.Name(), []byte(out), params.BeaconIoConfig().ReadWritePermissions)
 	require.NoError(t, err, "Could not write key to file")
 	log.WithField("file", file.Name()).WithField("key", out).Info("Wrote key to file")
 	cfg := &Config{

beacon-chain/p2p/peers/peers_test.go

@@ -1,7 +1,7 @@
 package peers_test
 
 import (
-	"io/ioutil"
+	"io"
 	"testing"
 
 	"github.com/prysmaticlabs/prysm/cmd/beacon-chain/flags"
@@ -11,7 +11,7 @@ import (
 
 func TestMain(m *testing.M) {
 	logrus.SetLevel(logrus.DebugLevel)
-	logrus.SetOutput(ioutil.Discard)
+	logrus.SetOutput(io.Discard)
 
 	resetCfg := features.InitWithReset(&features.Flags{
 		EnablePeerScorer: true,

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

@@ -145,5 +145,7 @@ func (s *PeerStatusScorer) peerStatus(pid peer.ID) (*pb.Status, error) {
 
 // SetHeadSlot updates known head slot.
 func (s *PeerStatusScorer) SetHeadSlot(slot types.Slot) {
+	s.store.Lock()
+	defer s.store.Unlock()
 	s.ourHeadSlot = slot
 }

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

@@ -1,7 +1,7 @@
 package scorers_test
 
 import (
-	"io/ioutil"
+	"io"
 	"math"
 	"testing"
 
@@ -13,7 +13,7 @@ import (
 
 func TestMain(m *testing.M) {
 	logrus.SetLevel(logrus.DebugLevel)
-	logrus.SetOutput(ioutil.Discard)
+	logrus.SetOutput(io.Discard)
 
 	resetCfg := features.InitWithReset(&features.Flags{
 		EnablePeerScorer: true,

beacon-chain/p2p/utils.go

@@ -7,7 +7,6 @@ import (
 	"encoding/base64"
 	"encoding/hex"
 	"fmt"
-	"io/ioutil"
 	"net"
 	"os"
 	"path"
@@ -89,7 +88,7 @@ func privKey(cfg *Config) (*ecdsa.PrivateKey, error) {
 
 // Retrieves a p2p networking private key from a file path.
 func privKeyFromFile(path string) (*ecdsa.PrivateKey, error) {
-	src, err := ioutil.ReadFile(path) // #nosec G304
+	src, err := os.ReadFile(path) // #nosec G304
 	if err != nil {
 		log.WithError(err).Error("Error reading private key from file")
 		return nil, err
@@ -135,7 +134,7 @@ func metaDataFromConfig(cfg *Config) (metadata.Metadata, error) {
 	if defaultMetadataExist && metaDataPath == "" {
 		metaDataPath = defaultKeyPath
 	}
-	src, err := ioutil.ReadFile(metaDataPath) // #nosec G304
+	src, err := os.ReadFile(metaDataPath) // #nosec G304
 	if err != nil {
 		log.WithError(err).Error("Error reading metadata from file")
 		return nil, err

beacon-chain/powchain/BUILD.bazel

@@ -3,7 +3,6 @@ load("@prysm//tools/go:def.bzl", "go_library", "go_test")
 go_library(
     name = "go_default_library",
     srcs = [
-        "auth.go",
         "block_cache.go",
         "block_reader.go",
         "check_transition_config.go",
@@ -16,6 +15,7 @@ go_library(
         "options.go",
         "prometheus.go",
         "provider.go",
+        "rpc_connection.go",
         "service.go",
     ],
     importpath = "github.com/prysmaticlabs/prysm/beacon-chain/powchain",
@@ -59,7 +59,6 @@ go_library(
         "@com_github_ethereum_go_ethereum//core/types:go_default_library",
         "@com_github_ethereum_go_ethereum//ethclient:go_default_library",
         "@com_github_ethereum_go_ethereum//rpc:go_default_library",
-        "@com_github_golang_jwt_jwt_v4//:go_default_library",
         "@com_github_holiman_uint256//:go_default_library",
         "@com_github_pkg_errors//:go_default_library",
         "@com_github_prometheus_client_golang//prometheus:go_default_library",
@@ -74,7 +73,6 @@ go_test(
     name = "go_default_test",
     size = "medium",
     srcs = [
-        "auth_test.go",
         "block_cache_test.go",
         "block_reader_test.go",
         "check_transition_config_test.go",
@@ -125,7 +123,6 @@ go_test(
         "@com_github_ethereum_go_ethereum//core/types:go_default_library",
         "@com_github_ethereum_go_ethereum//rpc:go_default_library",
         "@com_github_ethereum_go_ethereum//trie:go_default_library",
-        "@com_github_golang_jwt_jwt_v4//:go_default_library",
         "@com_github_holiman_uint256//:go_default_library",
         "@com_github_pkg_errors//:go_default_library",
         "@com_github_prometheus_client_golang//prometheus:go_default_library",

beacon-chain/powchain/block_reader.go

@@ -114,11 +114,13 @@ func (s *Service) BlockByTimestamp(ctx context.Context, time uint64) (*types.Hea
 	ctx, span := trace.StartSpan(ctx, "beacon-chain.web3service.BlockByTimestamp")
 	defer span.End()
 
+	s.latestEth1DataLock.RLock()
 	latestBlkHeight := s.latestEth1Data.BlockHeight
 	latestBlkTime := s.latestEth1Data.BlockTime
+	s.latestEth1DataLock.RUnlock()
 
 	if time > latestBlkTime {
-		return nil, errors.New("provided time is later than the current eth1 head")
+		return nil, errors.Errorf("provided time is later than the current eth1 head. %d > %d", time, latestBlkTime)
 	}
 	// Initialize a pointer to eth1 chain's history to start our search
 	// from.

beacon-chain/powchain/check_transition_config.go

@@ -13,6 +13,7 @@ import (
 	"github.com/prysmaticlabs/prysm/beacon-chain/core/feed"
 	statefeed "github.com/prysmaticlabs/prysm/beacon-chain/core/feed/state"
 	"github.com/prysmaticlabs/prysm/config/params"
+	"github.com/prysmaticlabs/prysm/network"
 	pb "github.com/prysmaticlabs/prysm/proto/engine/v1"
 	"github.com/sirupsen/logrus"
 )
@@ -81,7 +82,7 @@ func (s *Service) checkTransitionConfiguration(
 				return
 			}
 		case tm := <-ticker.C:
-			ctx, cancel := context.WithDeadline(ctx, tm.Add(DefaultRPCHTTPTimeout))
+			ctx, cancel := context.WithDeadline(ctx, tm.Add(network.DefaultRPCHTTPTimeout))
 			err = s.ExchangeTransitionConfiguration(ctx, cfg)
 			s.handleExchangeConfigurationError(err)
 			if !hasTtdReached {
@@ -119,11 +120,16 @@ func (s *Service) handleExchangeConfigurationError(err error) {
 // Logs the terminal total difficulty status.
 func (s *Service) logTtdStatus(ctx context.Context, ttd *uint256.Int) (bool, error) {
 	latest, err := s.LatestExecutionBlock(ctx)
-	if err != nil {
+	switch {
+	case errors.Is(err, hexutil.ErrEmptyString):
+		return false, nil
+	case err != nil:
 		return false, err
-	}
-	if latest == nil {
+	case latest == nil:
 		return false, errors.New("latest block is nil")
+	case latest.TotalDifficulty == "":
+		return false, nil
+	default:
 	}
 	latestTtd, err := hexutil.DecodeBig(latest.TotalDifficulty)
 	if err != nil {

beacon-chain/powchain/check_transition_config_test.go

@@ -190,6 +190,38 @@ func TestService_logTtdStatus(t *testing.T) {
 	require.Equal(t, false, reached)
 }
 
+func TestService_logTtdStatus_NotSyncedClient(t *testing.T) {
+	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		w.Header().Set("Content-Type", "application/json")
+		defer func() {
+			require.NoError(t, r.Body.Close())
+		}()
+
+		resp := (*pb.ExecutionBlock)(nil) // Nil response when a client is not synced
+		respJSON := map[string]interface{}{
+			"jsonrpc": "2.0",
+			"id":      1,
+			"result":  resp,
+		}
+		require.NoError(t, json.NewEncoder(w).Encode(respJSON))
+	}))
+	defer srv.Close()
+
+	rpcClient, err := rpc.DialHTTP(srv.URL)
+	require.NoError(t, err)
+	defer rpcClient.Close()
+
+	service := &Service{
+		cfg: &config{},
+	}
+	service.rpcClient = rpcClient
+
+	ttd := new(uint256.Int)
+	reached, err := service.logTtdStatus(context.Background(), ttd.SetUint64(24343))
+	require.NoError(t, err)
+	require.Equal(t, false, reached)
+}
+
 func emptyPayload() *pb.ExecutionPayload {
 	return &pb.ExecutionPayload{
 		ParentHash:    make([]byte, fieldparams.RootLength),

beacon-chain/powchain/engine_client.go

@@ -10,9 +10,12 @@ import (
 	"github.com/ethereum/go-ethereum/common"
 	"github.com/ethereum/go-ethereum/common/hexutil"
 	"github.com/ethereum/go-ethereum/rpc"
+	"github.com/holiman/uint256"
 	"github.com/pkg/errors"
 	"github.com/prysmaticlabs/prysm/config/params"
+	"github.com/prysmaticlabs/prysm/encoding/bytesutil"
 	pb "github.com/prysmaticlabs/prysm/proto/engine/v1"
+	"github.com/sirupsen/logrus"
 	"go.opencensus.io/trace"
 )
 
@@ -49,8 +52,8 @@ type EngineCaller interface {
 	ExchangeTransitionConfiguration(
 		ctx context.Context, cfg *pb.TransitionConfiguration,
 	) error
-	LatestExecutionBlock(ctx context.Context) (*pb.ExecutionBlock, error)
 	ExecutionBlockByHash(ctx context.Context, hash common.Hash) (*pb.ExecutionBlock, error)
+	GetTerminalBlockHash(ctx context.Context) ([]byte, bool, error)
 }
 
 // NewPayload calls the engine_newPayloadV1 method via JSON-RPC.
@@ -174,6 +177,78 @@ func (s *Service) ExchangeTransitionConfiguration(
 	return nil
 }
 
+// GetTerminalBlockHash returns the valid terminal block hash based on total difficulty.
+//
+// Spec code:
+// def get_pow_block_at_terminal_total_difficulty(pow_chain: Dict[Hash32, PowBlock]) -> Optional[PowBlock]:
+//    # `pow_chain` abstractly represents all blocks in the PoW chain
+//    for block in pow_chain:
+//        parent = pow_chain[block.parent_hash]
+//        block_reached_ttd = block.total_difficulty >= TERMINAL_TOTAL_DIFFICULTY
+//        parent_reached_ttd = parent.total_difficulty >= TERMINAL_TOTAL_DIFFICULTY
+//        if block_reached_ttd and not parent_reached_ttd:
+//            return block
+//
+//    return None
+func (s *Service) GetTerminalBlockHash(ctx context.Context) ([]byte, bool, error) {
+	ttd := new(big.Int)
+	ttd.SetString(params.BeaconConfig().TerminalTotalDifficulty, 10)
+	terminalTotalDifficulty, overflows := uint256.FromBig(ttd)
+	if overflows {
+		return nil, false, errors.New("could not convert terminal total difficulty to uint256")
+	}
+	blk, err := s.LatestExecutionBlock(ctx)
+	if err != nil {
+		return nil, false, errors.Wrap(err, "could not get latest execution block")
+	}
+	if blk == nil {
+		return nil, false, errors.New("latest execution block is nil")
+	}
+
+	for {
+		if ctx.Err() != nil {
+			return nil, false, ctx.Err()
+		}
+		currentTotalDifficulty, err := tDStringToUint256(blk.TotalDifficulty)
+		if err != nil {
+			return nil, false, errors.Wrap(err, "could not convert total difficulty to uint256")
+		}
+		blockReachedTTD := currentTotalDifficulty.Cmp(terminalTotalDifficulty) >= 0
+
+		parentHash := bytesutil.ToBytes32(blk.ParentHash)
+		if len(blk.ParentHash) == 0 || parentHash == params.BeaconConfig().ZeroHash {
+			return nil, false, nil
+		}
+		parentBlk, err := s.ExecutionBlockByHash(ctx, parentHash)
+		if err != nil {
+			return nil, false, errors.Wrap(err, "could not get parent execution block")
+		}
+		if parentBlk == nil {
+			return nil, false, errors.New("parent execution block is nil")
+		}
+		if blockReachedTTD {
+			parentTotalDifficulty, err := tDStringToUint256(parentBlk.TotalDifficulty)
+			if err != nil {
+				return nil, false, errors.Wrap(err, "could not convert total difficulty to uint256")
+			}
+			parentReachedTTD := parentTotalDifficulty.Cmp(terminalTotalDifficulty) >= 0
+			if !parentReachedTTD {
+				log.WithFields(logrus.Fields{
+					"number":   blk.Number,
+					"hash":     fmt.Sprintf("%#x", bytesutil.Trunc(blk.Hash)),
+					"td":       blk.TotalDifficulty,
+					"parentTd": parentBlk.TotalDifficulty,
+					"ttd":      terminalTotalDifficulty,
+				}).Info("Retrieved terminal block hash")
+				return blk.Hash, true, nil
+			}
+		} else {
+			return nil, false, nil
+		}
+		blk = parentBlk
+	}
+}
+
 // LatestExecutionBlock fetches the latest execution engine block by calling
 // eth_blockByNumber via JSON-RPC.
 func (s *Service) LatestExecutionBlock(ctx context.Context) (*pb.ExecutionBlock, error) {
@@ -251,3 +326,15 @@ func isTimeout(e error) bool {
 	t, ok := e.(httpTimeoutError)
 	return ok && t.Timeout()
 }
+
+func tDStringToUint256(td string) (*uint256.Int, error) {
+	b, err := hexutil.DecodeBig(td)
+	if err != nil {
+		return nil, err
+	}
+	i, overflows := uint256.FromBig(b)
+	if overflows {
+		return nil, errors.New("total difficulty overflowed")
+	}
+	return i, nil
+}

beacon-chain/powchain/engine_client_test.go

@@ -4,7 +4,7 @@ import (
 	"context"
 	"encoding/json"
 	"fmt"
-	"io/ioutil"
+	"io"
 	"math/big"
 	"net/http"
 	"net/http/httptest"
@@ -100,7 +100,7 @@ func TestClient_HTTP(t *testing.T) {
 			defer func() {
 				require.NoError(t, r.Body.Close())
 			}()
-			enc, err := ioutil.ReadAll(r.Body)
+			enc, err := io.ReadAll(r.Body)
 			require.NoError(t, err)
 			jsonRequestString := string(enc)
 
@@ -350,7 +350,7 @@ func TestClient_HTTP(t *testing.T) {
 			defer func() {
 				require.NoError(t, r.Body.Close())
 			}()
-			enc, err := ioutil.ReadAll(r.Body)
+			enc, err := io.ReadAll(r.Body)
 			require.NoError(t, err)
 			jsonRequestString := string(enc)
 			// We expect the JSON string RPC request contains the right arguments.
@@ -387,7 +387,7 @@ func TestClient_HTTP(t *testing.T) {
 			defer func() {
 				require.NoError(t, r.Body.Close())
 			}()
-			enc, err := ioutil.ReadAll(r.Body)
+			enc, err := io.ReadAll(r.Body)
 			require.NoError(t, err)
 			jsonRequestString := string(enc)
 			// We expect the JSON string RPC request contains the right arguments.
@@ -418,6 +418,155 @@ func TestClient_HTTP(t *testing.T) {
 	})
 }
 
+func TestServer_getPowBlockHashAtTerminalTotalDifficulty(t *testing.T) {
+	tests := []struct {
+		name                  string
+		paramsTd              string
+		currentPowBlock       *pb.ExecutionBlock
+		parentPowBlock        *pb.ExecutionBlock
+		errLatestExecutionBlk error
+		wantTerminalBlockHash []byte
+		wantExists            bool
+		errString             string
+	}{
+		{
+			name:      "config td overflows",
+			paramsTd:  "1115792089237316195423570985008687907853269984665640564039457584007913129638912",
+			errString: "could not convert terminal total difficulty to uint256",
+		},
+		{
+			name:                  "could not get latest execution block",
+			paramsTd:              "1",
+			errLatestExecutionBlk: errors.New("blah"),
+			errString:             "could not get latest execution block",
+		},
+		{
+			name:      "nil latest execution block",
+			paramsTd:  "1",
+			errString: "latest execution block is nil",
+		},
+		{
+			name:     "current execution block invalid TD",
+			paramsTd: "1",
+			currentPowBlock: &pb.ExecutionBlock{
+				Hash:            []byte{'a'},
+				TotalDifficulty: "1115792089237316195423570985008687907853269984665640564039457584007913129638912",
+			},
+			errString: "could not convert total difficulty to uint256",
+		},
+		{
+			name:     "current execution block has zero hash parent",
+			paramsTd: "2",
+			currentPowBlock: &pb.ExecutionBlock{
+				Hash:            []byte{'a'},
+				ParentHash:      params.BeaconConfig().ZeroHash[:],
+				TotalDifficulty: "0x3",
+			},
+		},
+		{
+			name:     "could not get parent block",
+			paramsTd: "2",
+			currentPowBlock: &pb.ExecutionBlock{
+				Hash:            []byte{'a'},
+				ParentHash:      []byte{'b'},
+				TotalDifficulty: "0x3",
+			},
+			errString: "could not get parent execution block",
+		},
+		{
+			name:     "parent execution block invalid TD",
+			paramsTd: "2",
+			currentPowBlock: &pb.ExecutionBlock{
+				Hash:            []byte{'a'},
+				ParentHash:      []byte{'b'},
+				TotalDifficulty: "0x3",
+			},
+			parentPowBlock: &pb.ExecutionBlock{
+				Hash:            []byte{'b'},
+				ParentHash:      []byte{'c'},
+				TotalDifficulty: "1",
+			},
+			errString: "could not convert total difficulty to uint256",
+		},
+		{
+			name:     "happy case",
+			paramsTd: "2",
+			currentPowBlock: &pb.ExecutionBlock{
+				Hash:            []byte{'a'},
+				ParentHash:      []byte{'b'},
+				TotalDifficulty: "0x3",
+			},
+			parentPowBlock: &pb.ExecutionBlock{
+				Hash:            []byte{'b'},
+				ParentHash:      []byte{'c'},
+				TotalDifficulty: "0x1",
+			},
+			wantExists:            true,
+			wantTerminalBlockHash: []byte{'a'},
+		},
+		{
+			name:     "ttd not reached",
+			paramsTd: "3",
+			currentPowBlock: &pb.ExecutionBlock{
+				Hash:            []byte{'a'},
+				ParentHash:      []byte{'b'},
+				TotalDifficulty: "0x2",
+			},
+			parentPowBlock: &pb.ExecutionBlock{
+				Hash:            []byte{'b'},
+				ParentHash:      []byte{'c'},
+				TotalDifficulty: "0x1",
+			},
+		},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			cfg := params.BeaconConfig()
+			cfg.TerminalTotalDifficulty = tt.paramsTd
+			params.OverrideBeaconConfig(cfg)
+			var m map[[32]byte]*pb.ExecutionBlock
+			if tt.parentPowBlock != nil {
+				m = map[[32]byte]*pb.ExecutionBlock{
+					bytesutil.ToBytes32(tt.parentPowBlock.Hash): tt.parentPowBlock,
+				}
+			}
+			client := mocks.EngineClient{
+				ErrLatestExecBlock: tt.errLatestExecutionBlk,
+				ExecutionBlock:     tt.currentPowBlock,
+				BlockByHashMap:     m,
+			}
+			b, e, err := client.GetTerminalBlockHash(context.Background())
+			if tt.errString != "" {
+				require.ErrorContains(t, tt.errString, err)
+			} else {
+				require.NoError(t, err)
+				require.DeepEqual(t, tt.wantExists, e)
+				require.DeepEqual(t, tt.wantTerminalBlockHash, b)
+			}
+		})
+	}
+}
+
+func Test_tDStringToUint256(t *testing.T) {
+	i, err := tDStringToUint256("0x0")
+	require.NoError(t, err)
+	require.DeepEqual(t, uint256.NewInt(0), i)
+
+	i, err = tDStringToUint256("0x10000")
+	require.NoError(t, err)
+	require.DeepEqual(t, uint256.NewInt(65536), i)
+
+	_, err = tDStringToUint256("100")
+	require.ErrorContains(t, "hex string without 0x prefix", err)
+
+	_, err = tDStringToUint256("0xzzzzzz")
+	require.ErrorContains(t, "invalid hex string", err)
+
+	_, err = tDStringToUint256("0xFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF" +
+		"FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF")
+	require.ErrorContains(t, "hex number > 256 bits", err)
+}
+
 func TestExchangeTransitionConfiguration(t *testing.T) {
 	fix := fixtures()
 	ctx := context.Background()
@@ -823,7 +972,7 @@ func forkchoiceUpdateSetup(t *testing.T, fcs *pb.ForkchoiceState, att *pb.Payloa
 		defer func() {
 			require.NoError(t, r.Body.Close())
 		}()
-		enc, err := ioutil.ReadAll(r.Body)
+		enc, err := io.ReadAll(r.Body)
 		require.NoError(t, err)
 		jsonRequestString := string(enc)
 
@@ -862,7 +1011,7 @@ func newPayloadSetup(t *testing.T, status *pb.PayloadStatus, payload *pb.Executi
 		defer func() {
 			require.NoError(t, r.Body.Close())
 		}()
-		enc, err := ioutil.ReadAll(r.Body)
+		enc, err := io.ReadAll(r.Body)
 		require.NoError(t, err)
 		jsonRequestString := string(enc)
 

beacon-chain/powchain/log_processing.go

@@ -342,7 +342,9 @@ func (s *Service) processPastLogs(ctx context.Context) error {
 					return err
 				}
 				// set new block number after checking for chainstart for previous block.
+				s.latestEth1DataLock.Lock()
 				s.latestEth1Data.LastRequestedBlock = currentBlockNum
+				s.latestEth1DataLock.Unlock()
 				currentBlockNum = filterLog.BlockNumber
 			}
 			if err := s.ProcessLog(ctx, filterLog); err != nil {
@@ -363,7 +365,9 @@ func (s *Service) processPastLogs(ctx context.Context) error {
 		}
 	}
 
+	s.latestEth1DataLock.Lock()
 	s.latestEth1Data.LastRequestedBlock = currentBlockNum
+	s.latestEth1DataLock.Unlock()
 
 	c, err := s.cfg.beaconDB.FinalizedCheckpoint(ctx)
 	if err != nil {
@@ -421,7 +425,9 @@ func (s *Service) requestBatchedHeadersAndLogs(ctx context.Context) error {
 		if err != nil {
 			return err
 		}
+		s.latestEth1DataLock.Lock()
 		s.latestEth1Data.LastRequestedBlock = i
+		s.latestEth1DataLock.Unlock()
 	}
 
 	return nil

beacon-chain/powchain/options.go

@@ -1,9 +1,6 @@
 package powchain
 
 import (
-	"net/http"
-	"time"
-
 	"github.com/ethereum/go-ethereum/common"
 	"github.com/prysmaticlabs/prysm/beacon-chain/cache/depositcache"
 	statefeed "github.com/prysmaticlabs/prysm/beacon-chain/core/feed/state"
@@ -11,11 +8,9 @@ import (
 	"github.com/prysmaticlabs/prysm/beacon-chain/state"
 	"github.com/prysmaticlabs/prysm/beacon-chain/state/stategen"
 	"github.com/prysmaticlabs/prysm/network"
+	"github.com/prysmaticlabs/prysm/network/authorization"
 )
 
-// DefaultRPCHTTPTimeout for HTTP requests via an RPC connection to an execution node.
-const DefaultRPCHTTPTimeout = time.Second * 6
-
 type Option func(s *Service) error
 
 // WithHttpEndpoints deduplicates and parses http endpoints for the powchain service to use,
@@ -38,20 +33,29 @@ func WithHttpEndpoints(endpointStrings []string) Option {
 	}
 }
 
-// WithJWTSecret for authenticating the execution node JSON-RPC endpoint.
-func WithJWTSecret(secret []byte) Option {
-	return func(c *Service) error {
+// WithHttpEndpointsAndJWTSecret for authenticating the execution node JSON-RPC endpoint.
+func WithHttpEndpointsAndJWTSecret(endpointStrings []string, secret []byte) Option {
+	return func(s *Service) error {
 		if len(secret) == 0 {
 			return nil
 		}
-		authTransport := &jwtTransport{
-			underlyingTransport: http.DefaultTransport,
-			jwtSecret:           secret,
+		stringEndpoints := dedupEndpoints(endpointStrings)
+		endpoints := make([]network.Endpoint, len(stringEndpoints))
+		// Overwrite authorization type for all endpoints to be of a bearer
+		// type.
+		for i, e := range stringEndpoints {
+			hEndpoint := HttpEndpoint(e)
+			hEndpoint.Auth.Method = authorization.Bearer
+			hEndpoint.Auth.Value = string(secret)
+			endpoints[i] = hEndpoint
 		}
-		c.cfg.httpRPCClient = &http.Client{
-			Timeout:   DefaultRPCHTTPTimeout,
-			Transport: authTransport,
+		// Select first http endpoint in the provided list.
+		var currEndpoint network.Endpoint
+		if len(endpointStrings) > 0 {
+			currEndpoint = endpoints[0]
 		}
+		s.cfg.httpEndpoints = endpoints
+		s.cfg.currHttpEndpoint = currEndpoint
 		return nil
 	}
 }

beacon-chain/powchain/powchain_test.go

@@ -1,7 +1,7 @@
 package powchain
 
 import (
-	"io/ioutil"
+	"io"
 	"testing"
 
 	"github.com/sirupsen/logrus"
@@ -9,7 +9,7 @@ import (
 
 func TestMain(m *testing.M) {
 	logrus.SetLevel(logrus.DebugLevel)
-	logrus.SetOutput(ioutil.Discard)
+	logrus.SetOutput(io.Discard)
 
 	m.Run()
 }

beacon-chain/powchain/rpc_connection.go

@@ -0,0 +1,176 @@
+package powchain
+
+import (
+	"context"
+	"fmt"
+	"net/url"
+	"time"
+
+	"github.com/ethereum/go-ethereum/ethclient"
+	gethRPC "github.com/ethereum/go-ethereum/rpc"
+	"github.com/pkg/errors"
+	"github.com/prysmaticlabs/prysm/config/params"
+	contracts "github.com/prysmaticlabs/prysm/contracts/deposit"
+	"github.com/prysmaticlabs/prysm/io/logs"
+	"github.com/prysmaticlabs/prysm/network"
+	"github.com/prysmaticlabs/prysm/network/authorization"
+)
+
+func (s *Service) setupExecutionClientConnections(ctx context.Context, currEndpoint network.Endpoint) error {
+	client, err := s.newRPCClientWithAuth(ctx, currEndpoint)
+	if err != nil {
+		return errors.Wrap(err, "could not dial execution node")
+	}
+	// Attach the clients to the service struct.
+	fetcher := ethclient.NewClient(client)
+	s.rpcClient = client
+	s.httpLogger = fetcher
+	s.eth1DataFetcher = fetcher
+
+	depositContractCaller, err := contracts.NewDepositContractCaller(s.cfg.depositContractAddr, fetcher)
+	if err != nil {
+		client.Close()
+		return errors.Wrap(err, "could not initialize deposit contract caller")
+	}
+	s.depositContractCaller = depositContractCaller
+
+	// Ensure we have the correct chain and deposit IDs.
+	if err := ensureCorrectExecutionChain(ctx, fetcher); err != nil {
+		client.Close()
+		return errors.Wrap(err, "could not make initial request to verify execution chain ID")
+	}
+	s.updateConnectedETH1(true)
+	s.runError = nil
+	return nil
+}
+
+// Every N seconds, defined as a backoffPeriod, attempts to re-establish an execution client
+// connection and if this does not work, we fallback to the next endpoint if defined.
+func (s *Service) pollConnectionStatus(ctx context.Context) {
+	// Use a custom logger to only log errors
+	logCounter := 0
+	errorLogger := func(err error, msg string) {
+		if logCounter > logThreshold {
+			log.Errorf("%s: %v", msg, err)
+			logCounter = 0
+		}
+		logCounter++
+	}
+	ticker := time.NewTicker(backOffPeriod)
+	defer ticker.Stop()
+	for {
+		select {
+		case <-ticker.C:
+			log.Debugf("Trying to dial endpoint: %s", logs.MaskCredentialsLogging(s.cfg.currHttpEndpoint.Url))
+			if err := s.setupExecutionClientConnections(ctx, s.cfg.currHttpEndpoint); err != nil {
+				errorLogger(err, "Could not connect to execution client endpoint")
+				s.runError = err
+				s.fallbackToNextEndpoint()
+			}
+		case <-s.ctx.Done():
+			log.Debug("Received cancelled context,closing existing powchain service")
+			return
+		}
+	}
+}
+
+// Forces to retry an execution client connection.
+func (s *Service) retryExecutionClientConnection(ctx context.Context, err error) {
+	s.runError = err
+	s.updateConnectedETH1(false)
+	// Back off for a while before redialing.
+	time.Sleep(backOffPeriod)
+	if err := s.setupExecutionClientConnections(ctx, s.cfg.currHttpEndpoint); err != nil {
+		s.runError = err
+		return
+	}
+	// Reset run error in the event of a successful connection.
+	s.runError = nil
+}
+
+// This performs a health check on our primary endpoint, and if it
+// is ready to serve we connect to it again. This method is only
+// relevant if we are on our backup endpoint.
+func (s *Service) checkDefaultEndpoint(ctx context.Context) {
+	primaryEndpoint := s.cfg.httpEndpoints[0]
+	// Return early if we are running on our primary
+	// endpoint.
+	if s.cfg.currHttpEndpoint.Equals(primaryEndpoint) {
+		return
+	}
+
+	if err := s.setupExecutionClientConnections(ctx, primaryEndpoint); err != nil {
+		log.Debugf("Primary endpoint not ready: %v", err)
+		return
+	}
+	s.updateCurrHttpEndpoint(primaryEndpoint)
+}
+
+// This is an inefficient way to search for the next endpoint, but given N is
+// expected to be small, it is fine to search this way.
+func (s *Service) fallbackToNextEndpoint() {
+	currEndpoint := s.cfg.currHttpEndpoint
+	currIndex := 0
+	totalEndpoints := len(s.cfg.httpEndpoints)
+
+	for i, endpoint := range s.cfg.httpEndpoints {
+		if endpoint.Equals(currEndpoint) {
+			currIndex = i
+			break
+		}
+	}
+	nextIndex := currIndex + 1
+	if nextIndex >= totalEndpoints {
+		nextIndex = 0
+	}
+	s.updateCurrHttpEndpoint(s.cfg.httpEndpoints[nextIndex])
+	if nextIndex != currIndex {
+		log.Infof("Falling back to alternative endpoint: %s", logs.MaskCredentialsLogging(s.cfg.currHttpEndpoint.Url))
+	}
+}
+
+// Initializes an RPC connection with authentication headers.
+func (s *Service) newRPCClientWithAuth(ctx context.Context, endpoint network.Endpoint) (*gethRPC.Client, error) {
+	// Need to handle ipc and http
+	var client *gethRPC.Client
+	u, err := url.Parse(endpoint.Url)
+	if err != nil {
+		return nil, err
+	}
+	switch u.Scheme {
+	case "http", "https":
+		client, err = gethRPC.DialHTTPWithClient(endpoint.Url, endpoint.HttpClient())
+		if err != nil {
+			return nil, err
+		}
+	case "":
+		client, err = gethRPC.DialIPC(ctx, endpoint.Url)
+		if err != nil {
+			return nil, err
+		}
+	default:
+		return nil, fmt.Errorf("no known transport for URL scheme %q", u.Scheme)
+	}
+	if endpoint.Auth.Method != authorization.None {
+		header, err := endpoint.Auth.ToHeaderValue()
+		if err != nil {
+			return nil, err
+		}
+		client.SetHeader("Authorization", header)
+	}
+	return client, nil
+}
+
+// Checks the chain ID of the execution client to ensure
+// it matches local parameters of what Prysm expects.
+func ensureCorrectExecutionChain(ctx context.Context, client *ethclient.Client) error {
+	cID, err := client.ChainID(ctx)
+	if err != nil {
+		return err
+	}
+	wantChainID := params.BeaconConfig().DepositChainID
+	if cID.Uint64() != wantChainID {
+		return fmt.Errorf("wanted chain ID %d, got %d", wantChainID, cID.Uint64())
+	}
+	return nil
+}

beacon-chain/powchain/service.go

@@ -7,7 +7,6 @@ import (
 	"context"
 	"fmt"
 	"math/big"
-	"net/http"
 	"reflect"
 	"runtime/debug"
 	"sort"
@@ -39,10 +38,8 @@ import (
 	"github.com/prysmaticlabs/prysm/container/trie"
 	contracts "github.com/prysmaticlabs/prysm/contracts/deposit"
 	"github.com/prysmaticlabs/prysm/encoding/bytesutil"
-	"github.com/prysmaticlabs/prysm/io/logs"
 	"github.com/prysmaticlabs/prysm/monitoring/clientstats"
 	"github.com/prysmaticlabs/prysm/network"
-	"github.com/prysmaticlabs/prysm/network/authorization"
 	ethpb "github.com/prysmaticlabs/prysm/proto/prysm/v1alpha1"
 	prysmTime "github.com/prysmaticlabs/prysm/time"
 	"github.com/prysmaticlabs/prysm/time/slots"
@@ -114,6 +111,7 @@ type Chain interface {
 // RPCDataFetcher defines a subset of methods conformed to by ETH1.0 RPC clients for
 // fetching eth1 data from the clients.
 type RPCDataFetcher interface {
+	Close()
 	HeaderByNumber(ctx context.Context, number *big.Int) (*gethTypes.Header, error)
 	HeaderByHash(ctx context.Context, hash common.Hash) (*gethTypes.Header, error)
 	SyncProgress(ctx context.Context) (*ethereum.SyncProgress, error)
@@ -121,6 +119,7 @@ type RPCDataFetcher interface {
 
 // RPCClient defines the rpc methods required to interact with the eth1 node.
 type RPCClient interface {
+	Close()
 	BatchCall(b []gethRPC.BatchElem) error
 	CallContext(ctx context.Context, result interface{}, method string, args ...interface{}) error
 }
@@ -135,7 +134,6 @@ type config struct {
 	eth1HeaderReqLimit      uint64
 	beaconNodeStatsUpdater  BeaconNodeStatsUpdater
 	httpEndpoints           []network.Endpoint
-	httpRPCClient           *http.Client
 	currHttpEndpoint        network.Endpoint
 	finalizedStateAtStartup state.BeaconState
 }
@@ -150,6 +148,7 @@ type Service struct {
 	connectedETH1           bool
 	isRunning               bool
 	processingLock          sync.RWMutex
+	latestEth1DataLock      sync.RWMutex
 	cfg                     *config
 	ctx                     context.Context
 	cancel                  context.CancelFunc
@@ -228,14 +227,9 @@ func NewService(ctx context.Context, opts ...Option) (*Service, error) {
 
 // Start a web3 service's main event loop.
 func (s *Service) Start() {
-
-	if err := s.connectToPowChain(); err != nil {
-		log.WithError(err).Fatal("Could not connect to execution endpoint")
+	if err := s.setupExecutionClientConnections(s.ctx, s.cfg.currHttpEndpoint); err != nil {
+		log.WithError(err).Error("Could not connect to execution endpoint")
 	}
-
-	log.WithFields(logrus.Fields{
-		"endpoint": logs.MaskCredentialsLogging(s.cfg.currHttpEndpoint.Url),
-	}).Info("Connected to Ethereum execution client RPC")
 	// If the chain has not started already and we don't have access to eth1 nodes, we will not be
 	// able to generate the genesis state.
 	if !s.chainStartData.Chainstarted && s.cfg.currHttpEndpoint.Url == "" {
@@ -253,7 +247,7 @@ func (s *Service) Start() {
 	s.isRunning = true
 
 	// Poll the execution client connection and fallback if errors occur.
-	go s.pollConnectionStatus()
+	go s.pollConnectionStatus(s.ctx)
 
 	// Check transition configuration for the engine API client in the background.
 	go s.checkTransitionConfiguration(s.ctx, make(chan *feed.Event, 1))
@@ -266,7 +260,12 @@ func (s *Service) Stop() error {
 	if s.cancel != nil {
 		defer s.cancel()
 	}
-	s.closeClients()
+	if s.rpcClient != nil {
+		s.rpcClient.Close()
+	}
+	if s.eth1DataFetcher != nil {
+		s.eth1DataFetcher.Close()
+	}
 	return nil
 }
 
@@ -338,10 +337,7 @@ func (s *Service) CurrentETH1Endpoint() string {
 
 // CurrentETH1ConnectionError returns the error (if any) of the current connection.
 func (s *Service) CurrentETH1ConnectionError() error {
-	httpClient, rpcClient, err := s.dialETH1Nodes(s.cfg.currHttpEndpoint)
-	httpClient.Close()
-	rpcClient.Close()
-	return err
+	return s.runError
 }
 
 // ETH1Endpoints returns the slice of HTTP endpoint URLs (default is 0th element).
@@ -358,10 +354,17 @@ func (s *Service) ETH1Endpoints() []string {
 func (s *Service) ETH1ConnectionErrors() []error {
 	var errs []error
 	for _, ep := range s.cfg.httpEndpoints {
-		httpClient, rpcClient, err := s.dialETH1Nodes(ep)
-		httpClient.Close()
-		rpcClient.Close()
-		errs = append(errs, err)
+		client, err := s.newRPCClientWithAuth(s.ctx, ep)
+		if err != nil {
+			errs = append(errs, err)
+			continue
+		}
+		if err := ensureCorrectExecutionChain(s.ctx, ethclient.NewClient(client)); err != nil {
+			client.Close()
+			errs = append(errs, err)
+			continue
+		}
+		client.Close()
 	}
 	return errs
 }
@@ -376,146 +379,6 @@ func (s *Service) followBlockHeight(_ context.Context) (uint64, error) {
 	return latestValidBlock, nil
 }
 
-func (s *Service) connectToPowChain() error {
-	httpClient, rpcClient, err := s.dialETH1Nodes(s.cfg.currHttpEndpoint)
-	if err != nil {
-		return errors.Wrap(err, "could not dial execution node")
-	}
-
-	depositContractCaller, err := contracts.NewDepositContractCaller(s.cfg.depositContractAddr, httpClient)
-	if err != nil {
-		return errors.Wrap(err, "could not initialize deposit contract caller")
-	}
-
-	if httpClient == nil || rpcClient == nil || depositContractCaller == nil {
-		return errors.New("execution client RPC is nil")
-	}
-	s.httpLogger = httpClient
-	s.eth1DataFetcher = httpClient
-	s.depositContractCaller = depositContractCaller
-	s.rpcClient = rpcClient
-
-	s.updateConnectedETH1(true)
-	s.runError = nil
-	return nil
-}
-
-func (s *Service) dialETH1Nodes(endpoint network.Endpoint) (*ethclient.Client, *gethRPC.Client, error) {
-	httpRPCClient, err := gethRPC.Dial(endpoint.Url)
-	if err != nil {
-		return nil, nil, err
-	}
-	if endpoint.Auth.Method != authorization.None {
-		header, err := endpoint.Auth.ToHeaderValue()
-		if err != nil {
-			return nil, nil, err
-		}
-		httpRPCClient.SetHeader("Authorization", header)
-	}
-	httpClient := ethclient.NewClient(httpRPCClient)
-	// Add a method to clean-up and close clients in the event
-	// of any connection failure.
-	closeClients := func() {
-		httpRPCClient.Close()
-		httpClient.Close()
-	}
-	// Make a simple call to ensure we are actually connected to a working node.
-	cID, err := httpClient.ChainID(s.ctx)
-	if err != nil {
-		closeClients()
-		return nil, nil, err
-	}
-	nID, err := httpClient.NetworkID(s.ctx)
-	if err != nil {
-		closeClients()
-		return nil, nil, err
-	}
-	if cID.Uint64() != params.BeaconConfig().DepositChainID {
-		closeClients()
-		return nil, nil, fmt.Errorf("eth1 node using incorrect chain id, %d != %d", cID.Uint64(), params.BeaconConfig().DepositChainID)
-	}
-	if nID.Uint64() != params.BeaconConfig().DepositNetworkID {
-		closeClients()
-		return nil, nil, fmt.Errorf("eth1 node using incorrect network id, %d != %d", nID.Uint64(), params.BeaconConfig().DepositNetworkID)
-	}
-
-	return httpClient, httpRPCClient, nil
-}
-
-// closes down our active eth1 clients.
-func (s *Service) closeClients() {
-	gethClient, ok := s.rpcClient.(*gethRPC.Client)
-	if ok {
-		gethClient.Close()
-	}
-	httpClient, ok := s.eth1DataFetcher.(*ethclient.Client)
-	if ok {
-		httpClient.Close()
-	}
-}
-
-func (s *Service) pollConnectionStatus() {
-	// Use a custom logger to only log errors
-	logCounter := 0
-	errorLogger := func(err error, msg string) {
-		if logCounter > logThreshold {
-			log.Errorf("%s: %v", msg, err)
-			logCounter = 0
-		}
-		logCounter++
-	}
-	ticker := time.NewTicker(backOffPeriod)
-	defer ticker.Stop()
-	for {
-		select {
-		case <-ticker.C:
-			log.Debugf("Trying to dial endpoint: %s", logs.MaskCredentialsLogging(s.cfg.currHttpEndpoint.Url))
-			errConnect := s.connectToPowChain()
-			if errConnect != nil {
-				errorLogger(errConnect, "Could not connect to powchain endpoint")
-				s.runError = errConnect
-				s.fallbackToNextEndpoint()
-				continue
-			}
-		case <-s.ctx.Done():
-			log.Debug("Received cancelled context,closing existing powchain service")
-			return
-		}
-	}
-}
-
-// checks if the eth1 node is healthy and ready to serve before
-// fetching data from  it.
-func (s *Service) isEth1NodeSynced() (bool, error) {
-	syncProg, err := s.eth1DataFetcher.SyncProgress(s.ctx)
-	if err != nil {
-		return false, err
-	}
-	if syncProg != nil {
-		return false, nil
-	}
-	head, err := s.eth1DataFetcher.HeaderByNumber(s.ctx, nil)
-	if err != nil {
-		return false, err
-	}
-	return !eth1HeadIsBehind(head.Time), nil
-}
-
-// Reconnect to eth1 node in case of any failure.
-func (s *Service) retryETH1Node(err error) {
-	s.runError = err
-	s.updateConnectedETH1(false)
-	// Back off for a while before
-	// resuming dialing the eth1 node.
-	time.Sleep(backOffPeriod)
-	if err := s.connectToPowChain(); err != nil {
-		s.runError = err
-		return
-	}
-	// Reset run error in the event of a successful connection.
-	s.runError = nil
-}
-
 func (s *Service) initDepositCaches(ctx context.Context, ctrs []*ethpb.DepositContainer) error {
 	if len(ctrs) == 0 {
 		return nil
@@ -551,11 +414,14 @@ func (s *Service) initDepositCaches(ctx context.Context, ctrs []*ethpb.DepositCo
 		// accumulates. we finalize them here before we are ready to receive a block.
 		// Otherwise, the first few blocks will be slower to compute as we will
 		// hold the lock and be busy finalizing the deposits.
-		s.cfg.depositCache.InsertFinalizedDeposits(ctx, int64(currIndex)) // lint:ignore uintcast -- deposit index will not exceed int64 in your lifetime.
+		// The deposit index in the state is always the index of the next deposit
+		// to be included(rather than the last one to be processed). This was most likely
+		// done as the state cannot represent signed integers.
+		actualIndex := int64(currIndex) - 1 // lint:ignore uintcast -- deposit index will not exceed int64 in your lifetime.
+		s.cfg.depositCache.InsertFinalizedDeposits(ctx, actualIndex)
 		// Deposit proofs are only used during state transition and can be safely removed to save space.
 
-		// lint:ignore uintcast -- deposit index will not exceed int64 in your lifetime.
-		if err = s.cfg.depositCache.PruneProofs(ctx, int64(currIndex)); err != nil {
+		if err = s.cfg.depositCache.PruneProofs(ctx, actualIndex); err != nil {
 			return errors.Wrap(err, "could not prune deposit proofs")
 		}
 	}
@@ -575,9 +441,11 @@ func (s *Service) initDepositCaches(ctx context.Context, ctrs []*ethpb.DepositCo
 func (s *Service) processBlockHeader(header *gethTypes.Header) {
 	defer safelyHandlePanic()
 	blockNumberGauge.Set(float64(header.Number.Int64()))
+	s.latestEth1DataLock.Lock()
 	s.latestEth1Data.BlockHeight = header.Number.Uint64()
 	s.latestEth1Data.BlockHash = header.Hash().Bytes()
 	s.latestEth1Data.BlockTime = header.Time
+	s.latestEth1DataLock.Unlock()
 	log.WithFields(logrus.Fields{
 		"blockNumber": s.latestEth1Data.BlockHeight,
 		"blockHash":   hexutil.Encode(s.latestEth1Data.BlockHash),
@@ -650,7 +518,7 @@ func (s *Service) handleETH1FollowDistance() {
 	fiveMinutesTimeout := prysmTime.Now().Add(-5 * time.Minute)
 	// check that web3 client is syncing
 	if time.Unix(int64(s.latestEth1Data.BlockTime), 0).Before(fiveMinutesTimeout) {
-		log.Warn("eth1 client is not syncing")
+		log.Warn("Execution client is not syncing")
 	}
 	if !s.chainStartData.Chainstarted {
 		if err := s.checkBlockNumberForChainStart(ctx, big.NewInt(int64(s.latestEth1Data.LastRequestedBlock))); err != nil {
@@ -680,6 +548,15 @@ func (s *Service) handleETH1FollowDistance() {
 }
 
 func (s *Service) initPOWService() {
+	// Use a custom logger to only log errors
+	logCounter := 0
+	errorLogger := func(err error, msg string) {
+		if logCounter > logThreshold {
+			log.Errorf("%s: %v", msg, err)
+			logCounter = 0
+		}
+		logCounter++
+	}
 
 	// Run in a select loop to retry in the event of any failures.
 	for {
@@ -690,24 +567,26 @@ func (s *Service) initPOWService() {
 			ctx := s.ctx
 			header, err := s.eth1DataFetcher.HeaderByNumber(ctx, nil)
 			if err != nil {
-				log.Errorf("Unable to retrieve latest ETH1.0 chain header: %v", err)
-				s.retryETH1Node(err)
+				s.retryExecutionClientConnection(ctx, err)
+				errorLogger(err, "Unable to retrieve latest execution client header")
 				continue
 			}
 
+			s.latestEth1DataLock.Lock()
 			s.latestEth1Data.BlockHeight = header.Number.Uint64()
 			s.latestEth1Data.BlockHash = header.Hash().Bytes()
 			s.latestEth1Data.BlockTime = header.Time
+			s.latestEth1DataLock.Unlock()
 
 			if err := s.processPastLogs(ctx); err != nil {
-				log.Errorf("Unable to process past logs %v", err)
-				s.retryETH1Node(err)
+				s.retryExecutionClientConnection(ctx, err)
+				errorLogger(err, "Unable to process past deposit contract logs")
 				continue
 			}
 			// Cache eth1 headers from our voting period.
 			if err := s.cacheHeadersForEth1DataVote(ctx); err != nil {
-				log.Errorf("Unable to process past headers %v", err)
-				s.retryETH1Node(err)
+				s.retryExecutionClientConnection(ctx, err)
+				errorLogger(err, "Unable to cache headers for execution client votes")
 				continue
 			}
 			// Handle edge case with embedded genesis state by fetching genesis header to determine
@@ -720,15 +599,15 @@ func (s *Service) initPOWService() {
 				if genHash != [32]byte{} {
 					genHeader, err := s.eth1DataFetcher.HeaderByHash(ctx, genHash)
 					if err != nil {
-						log.Errorf("Unable to retrieve genesis ETH1.0 chain header: %v", err)
-						s.retryETH1Node(err)
+						s.retryExecutionClientConnection(ctx, err)
+						errorLogger(err, "Unable to retrieve proof-of-stake genesis block data")
 						continue
 					}
 					genBlock = genHeader.Number.Uint64()
 				}
 				s.chainStartData.GenesisBlock = genBlock
 				if err := s.savePowchainData(ctx); err != nil {
-					log.Errorf("Unable to save powchain data: %v", err)
+					errorLogger(err, "Unable to save execution client data")
 				}
 			}
 			return
@@ -757,17 +636,16 @@ func (s *Service) run(done <-chan struct{}) {
 			head, err := s.eth1DataFetcher.HeaderByNumber(s.ctx, nil)
 			if err != nil {
 				log.WithError(err).Debug("Could not fetch latest eth1 header")
-				s.retryETH1Node(err)
 				continue
 			}
 			if eth1HeadIsBehind(head.Time) {
+				s.retryExecutionClientConnection(s.ctx, err)
 				log.WithError(errFarBehind).Debug("Could not get an up to date eth1 header")
-				s.retryETH1Node(errFarBehind)
 				continue
 			}
 			s.processBlockHeader(head)
 			s.handleETH1FollowDistance()
-			s.checkDefaultEndpoint()
+			s.checkDefaultEndpoint(s.ctx)
 		case <-chainstartTicker.C:
 			if s.chainStartData.Chainstarted {
 				chainstartTicker.Stop()
@@ -854,59 +732,6 @@ func (s *Service) determineEarliestVotingBlock(ctx context.Context, followBlock
 	return hdr.Number.Uint64(), nil
 }
 
-// This performs a health check on our primary endpoint, and if it
-// is ready to serve we connect to it again. This method is only
-// relevant if we are on our backup endpoint.
-func (s *Service) checkDefaultEndpoint() {
-	primaryEndpoint := s.cfg.httpEndpoints[0]
-	// Return early if we are running on our primary
-	// endpoint.
-	if s.cfg.currHttpEndpoint.Equals(primaryEndpoint) {
-		return
-	}
-
-	httpClient, rpcClient, err := s.dialETH1Nodes(primaryEndpoint)
-	if err != nil {
-		log.Debugf("Primary endpoint not ready: %v", err)
-		return
-	}
-	log.Info("Primary endpoint ready again, switching back to it")
-	// Close the clients and let our main connection routine
-	// properly connect with it.
-	httpClient.Close()
-	rpcClient.Close()
-	// Close current active clients.
-	s.closeClients()
-
-	// Switch back to primary endpoint and try connecting
-	// to it again.
-	s.updateCurrHttpEndpoint(primaryEndpoint)
-	s.retryETH1Node(nil)
-}
-
-// This is an inefficient way to search for the next endpoint, but given N is expected to be
-// small ( < 25), it is fine to search this way.
-func (s *Service) fallbackToNextEndpoint() {
-	currEndpoint := s.cfg.currHttpEndpoint
-	currIndex := 0
-	totalEndpoints := len(s.cfg.httpEndpoints)
-
-	for i, endpoint := range s.cfg.httpEndpoints {
-		if endpoint.Equals(currEndpoint) {
-			currIndex = i
-			break
-		}
-	}
-	nextIndex := currIndex + 1
-	if nextIndex >= totalEndpoints {
-		nextIndex = 0
-	}
-	s.updateCurrHttpEndpoint(s.cfg.httpEndpoints[nextIndex])
-	if nextIndex != currIndex {
-		log.Infof("Falling back to alternative endpoint: %s", logs.MaskCredentialsLogging(s.cfg.currHttpEndpoint.Url))
-	}
-}
-
 // initializes our service from the provided eth1data object by initializing all the relevant
 // fields and data.
 func (s *Service) initializeEth1Data(ctx context.Context, eth1DataInDB *ethpb.ETH1ChainData) error {

beacon-chain/powchain/service_test.go

@@ -42,6 +42,8 @@ type goodLogger struct {
 	backend *backends.SimulatedBackend
 }
 
+func (_ *goodLogger) Close() {}
+
 func (g *goodLogger) SubscribeFilterLogs(ctx context.Context, q ethereum.FilterQuery, ch chan<- gethTypes.Log) (ethereum.Subscription, error) {
 	if g.backend == nil {
 		return new(event.Feed).Subscribe(ch), nil
@@ -80,6 +82,8 @@ type goodFetcher struct {
 	backend *backends.SimulatedBackend
 }
 
+func (_ *goodFetcher) Close() {}
+
 func (g *goodFetcher) HeaderByHash(_ context.Context, hash common.Hash) (*gethTypes.Header, error) {
 	if bytes.Equal(hash.Bytes(), common.BytesToHash([]byte{0}).Bytes()) {
 		return nil, fmt.Errorf("expected block hash to be nonzero %v", hash)
@@ -225,10 +229,6 @@ func TestService_Eth1Synced(t *testing.T) {
 	now := time.Now()
 	assert.NoError(t, testAcc.Backend.AdjustTime(now.Sub(time.Unix(int64(currTime), 0))))
 	testAcc.Backend.Commit()
-
-	synced, err := web3Service.isEth1NodeSynced()
-	require.NoError(t, err)
-	assert.Equal(t, true, synced, "Expected eth1 nodes to be synced")
 }
 
 func TestFollowBlock_OK(t *testing.T) {
@@ -472,7 +472,7 @@ func TestInitDepositCacheWithFinalization_OK(t *testing.T) {
 	require.NoError(t, s.cfg.beaconDB.SaveState(context.Background(), emptyState, headRoot))
 	require.NoError(t, stateGen.SaveState(context.Background(), headRoot, emptyState))
 	s.cfg.stateGen = stateGen
-	require.NoError(t, emptyState.SetEth1DepositIndex(2))
+	require.NoError(t, emptyState.SetEth1DepositIndex(3))
 
 	ctx := context.Background()
 	require.NoError(t, beaconDB.SaveFinalizedCheckpoint(ctx, &ethpb.Checkpoint{Epoch: slots.ToEpoch(0), Root: headRoot[:]}))
@@ -480,8 +480,8 @@ func TestInitDepositCacheWithFinalization_OK(t *testing.T) {
 
 	s.chainStartData.Chainstarted = true
 	require.NoError(t, s.initDepositCaches(context.Background(), ctrs))
-
-	deps := s.cfg.depositCache.NonFinalizedDeposits(context.Background(), nil)
+	fDeposits := s.cfg.depositCache.FinalizedDeposits(ctx)
+	deps := s.cfg.depositCache.NonFinalizedDeposits(context.Background(), fDeposits.MerkleTrieIndex, nil)
 	assert.Equal(t, 0, len(deps))
 }
 

beacon-chain/powchain/testing/BUILD.bazel

@@ -26,6 +26,7 @@ go_library(
         "@com_github_ethereum_go_ethereum//common/hexutil:go_default_library",
         "@com_github_ethereum_go_ethereum//core/types:go_default_library",
         "@com_github_ethereum_go_ethereum//rpc:go_default_library",
+        "@com_github_holiman_uint256//:go_default_library",
         "@com_github_pkg_errors//:go_default_library",
     ],
 )

beacon-chain/powchain/testing/mock_engine_client.go

@@ -2,25 +2,32 @@ package testing
 
 import (
 	"context"
+	"math/big"
 
 	"github.com/ethereum/go-ethereum/common"
+	"github.com/ethereum/go-ethereum/common/hexutil"
+	"github.com/holiman/uint256"
 	"github.com/pkg/errors"
+	"github.com/prysmaticlabs/prysm/config/params"
+	"github.com/prysmaticlabs/prysm/encoding/bytesutil"
 	pb "github.com/prysmaticlabs/prysm/proto/engine/v1"
 )
 
 // EngineClient --
 type EngineClient struct {
-	NewPayloadResp        []byte
-	PayloadIDBytes        *pb.PayloadIDBytes
-	ForkChoiceUpdatedResp []byte
-	ExecutionPayload      *pb.ExecutionPayload
-	ExecutionBlock        *pb.ExecutionBlock
-	Err                   error
-	ErrLatestExecBlock    error
-	ErrExecBlockByHash    error
-	ErrForkchoiceUpdated  error
-	ErrNewPayload         error
-	BlockByHashMap        map[[32]byte]*pb.ExecutionBlock
+	NewPayloadResp          []byte
+	PayloadIDBytes          *pb.PayloadIDBytes
+	ForkChoiceUpdatedResp   []byte
+	ExecutionPayload        *pb.ExecutionPayload
+	ExecutionBlock          *pb.ExecutionBlock
+	Err                     error
+	ErrLatestExecBlock      error
+	ErrExecBlockByHash      error
+	ErrForkchoiceUpdated    error
+	ErrNewPayload           error
+	BlockByHashMap          map[[32]byte]*pb.ExecutionBlock
+	TerminalBlockHash       []byte
+	TerminalBlockHashExists bool
 }
 
 // NewPayload --
@@ -58,3 +65,52 @@ func (e *EngineClient) ExecutionBlockByHash(_ context.Context, h common.Hash) (*
 	}
 	return b, e.ErrExecBlockByHash
 }
+
+// GetTerminalBlockHash --
+func (e *EngineClient) GetTerminalBlockHash(ctx context.Context) ([]byte, bool, error) {
+	ttd := new(big.Int)
+	ttd.SetString(params.BeaconConfig().TerminalTotalDifficulty, 10)
+	terminalTotalDifficulty, overflows := uint256.FromBig(ttd)
+	if overflows {
+		return nil, false, errors.New("could not convert terminal total difficulty to uint256")
+	}
+	blk, err := e.LatestExecutionBlock(ctx)
+	if err != nil {
+		return nil, false, errors.Wrap(err, "could not get latest execution block")
+	}
+	if blk == nil {
+		return nil, false, errors.New("latest execution block is nil")
+	}
+
+	for {
+		b, err := hexutil.DecodeBig(blk.TotalDifficulty)
+		if err != nil {
+			return nil, false, errors.Wrap(err, "could not convert total difficulty to uint256")
+		}
+		currentTotalDifficulty, _ := uint256.FromBig(b)
+		blockReachedTTD := currentTotalDifficulty.Cmp(terminalTotalDifficulty) >= 0
+
+		parentHash := bytesutil.ToBytes32(blk.ParentHash)
+		if len(blk.ParentHash) == 0 || parentHash == params.BeaconConfig().ZeroHash {
+			return nil, false, nil
+		}
+		parentBlk, err := e.ExecutionBlockByHash(ctx, parentHash)
+		if err != nil {
+			return nil, false, errors.Wrap(err, "could not get parent execution block")
+		}
+		if blockReachedTTD {
+			b, err := hexutil.DecodeBig(parentBlk.TotalDifficulty)
+			if err != nil {
+				return nil, false, errors.Wrap(err, "could not convert total difficulty to uint256")
+			}
+			parentTotalDifficulty, _ := uint256.FromBig(b)
+			parentReachedTTD := parentTotalDifficulty.Cmp(terminalTotalDifficulty) >= 0
+			if !parentReachedTTD {
+				return blk.Hash, true, nil
+			}
+		} else {
+			return nil, false, nil
+		}
+		blk = parentBlk
+	}
+}

beacon-chain/powchain/testing/mock_powchain.go

@@ -144,6 +144,8 @@ type RPCClient struct {
 	Backend *backends.SimulatedBackend
 }
 
+func (_ *RPCClient) Close() {}
+
 func (*RPCClient) CallContext(_ context.Context, _ interface{}, _ string, _ ...interface{}) error {
 	return nil
 }

beacon-chain/rpc/apimiddleware/custom_handlers.go

@@ -6,7 +6,6 @@ import (
 	"encoding/json"
 	"fmt"
 	"io"
-	"io/ioutil"
 	"net/http"
 	"strconv"
 	"strings"
@@ -179,7 +178,7 @@ func writeSSZResponseHeaderAndBody(grpcResp *http.Response, w http.ResponseWrite
 	} else {
 		w.WriteHeader(grpcResp.StatusCode)
 	}
-	if _, err := io.Copy(w, ioutil.NopCloser(bytes.NewReader(respSsz))); err != nil {
+	if _, err := io.Copy(w, io.NopCloser(bytes.NewReader(respSsz))); err != nil {
 		return apimiddleware.InternalServerErrorWithMessage(err, "could not write response message")
 	}
 	return nil

beacon-chain/rpc/apimiddleware/custom_hooks.go

@@ -4,6 +4,7 @@ import (
 	"bytes"
 	"encoding/json"
 	"fmt"
+	"io"
 	"io/ioutil"
 	"net/http"
 	"strconv"
@@ -36,7 +37,7 @@ func wrapFeeRecipientsArray(
 	if err != nil {
 		return false, apimiddleware.InternalServerErrorWithMessage(err, "could not marshal wrapped body")
 	}
-	req.Body = ioutil.NopCloser(bytes.NewReader(b))
+	req.Body = io.NopCloser(bytes.NewReader(b))
 	return true, nil
 }
 
@@ -57,7 +58,7 @@ func wrapAttestationsArray(
 		if err != nil {
 			return false, apimiddleware.InternalServerErrorWithMessage(err, "could not marshal wrapped body")
 		}
-		req.Body = ioutil.NopCloser(bytes.NewReader(b))
+		req.Body = io.NopCloser(bytes.NewReader(b))
 	}
 	return true, nil
 }
@@ -79,7 +80,7 @@ func wrapValidatorIndicesArray(
 		if err != nil {
 			return false, apimiddleware.InternalServerErrorWithMessage(err, "could not marshal wrapped body")
 		}
-		req.Body = ioutil.NopCloser(bytes.NewReader(b))
+		req.Body = io.NopCloser(bytes.NewReader(b))
 	}
 	return true, nil
 }
@@ -101,7 +102,7 @@ func wrapSignedAggregateAndProofArray(
 		if err != nil {
 			return false, apimiddleware.InternalServerErrorWithMessage(err, "could not marshal wrapped body")
 		}
-		req.Body = ioutil.NopCloser(bytes.NewReader(b))
+		req.Body = io.NopCloser(bytes.NewReader(b))
 	}
 	return true, nil
 }
@@ -123,7 +124,7 @@ func wrapBeaconCommitteeSubscriptionsArray(
 		if err != nil {
 			return false, apimiddleware.InternalServerErrorWithMessage(err, "could not marshal wrapped body")
 		}
-		req.Body = ioutil.NopCloser(bytes.NewReader(b))
+		req.Body = io.NopCloser(bytes.NewReader(b))
 	}
 	return true, nil
 }
@@ -145,7 +146,7 @@ func wrapSyncCommitteeSubscriptionsArray(
 		if err != nil {
 			return false, apimiddleware.InternalServerErrorWithMessage(err, "could not marshal wrapped body")
 		}
-		req.Body = ioutil.NopCloser(bytes.NewReader(b))
+		req.Body = io.NopCloser(bytes.NewReader(b))
 	}
 	return true, nil
 }
@@ -167,7 +168,7 @@ func wrapSyncCommitteeSignaturesArray(
 		if err != nil {
 			return false, apimiddleware.InternalServerErrorWithMessage(err, "could not marshal wrapped body")
 		}
-		req.Body = ioutil.NopCloser(bytes.NewReader(b))
+		req.Body = io.NopCloser(bytes.NewReader(b))
 	}
 	return true, nil
 }
@@ -189,7 +190,7 @@ func wrapSignedContributionAndProofsArray(
 		if err != nil {
 			return false, apimiddleware.InternalServerErrorWithMessage(err, "could not marshal wrapped body")
 		}
-		req.Body = ioutil.NopCloser(bytes.NewReader(b))
+		req.Body = io.NopCloser(bytes.NewReader(b))
 	}
 	return true, nil
 }
@@ -209,6 +210,11 @@ type bellatrixPublishBlockRequestJson struct {
 	Signature      string                    `json:"signature" hex:"true"`
 }
 
+type bellatrixPublishBlindedBlockRequestJson struct {
+	BellatrixBlock *blindedBeaconBlockBellatrixJson `json:"bellatrix_block"`
+	Signature      string                           `json:"signature" hex:"true"`
+}
+
 // setInitialPublishBlockPostRequest is triggered before we deserialize the request JSON into a struct.
 // We don't know which version of the block got posted, but we can determine it from the slot.
 // We know that blocks of all versions have a Message field with a Slot field,
@@ -224,7 +230,7 @@ func setInitialPublishBlockPostRequest(endpoint *apimiddleware.Endpoint,
 		}
 	}{}
 
-	buf, err := ioutil.ReadAll(req.Body)
+	buf, err := io.ReadAll(req.Body)
 	if err != nil {
 		return false, apimiddleware.InternalServerErrorWithMessage(err, "could not read body")
 	}
@@ -243,7 +249,7 @@ func setInitialPublishBlockPostRequest(endpoint *apimiddleware.Endpoint,
 	} else {
 		endpoint.PostRequest = &signedBeaconBlockBellatrixContainerJson{}
 	}
-	req.Body = ioutil.NopCloser(bytes.NewBuffer(buf))
+	req.Body = io.NopCloser(bytes.NewBuffer(buf))
 	return true, nil
 }
 
@@ -282,6 +288,79 @@ func preparePublishedBlock(endpoint *apimiddleware.Endpoint, _ http.ResponseWrit
 	return apimiddleware.InternalServerError(errors.New("unsupported block type"))
 }
 
+// setInitialPublishBlindedBlockPostRequest is triggered before we deserialize the request JSON into a struct.
+// We don't know which version of the block got posted, but we can determine it from the slot.
+// We know that blocks of all versions have a Message field with a Slot field,
+// so we deserialize the request into a struct s, which has the right fields, to obtain the slot.
+// Once we know the slot, we can determine what the PostRequest field of the endpoint should be, and we set it appropriately.
+func setInitialPublishBlindedBlockPostRequest(endpoint *apimiddleware.Endpoint,
+	_ http.ResponseWriter,
+	req *http.Request,
+) (apimiddleware.RunDefault, apimiddleware.ErrorJson) {
+	s := struct {
+		Message struct {
+			Slot string
+		}
+	}{}
+
+	buf, err := ioutil.ReadAll(req.Body)
+	if err != nil {
+		return false, apimiddleware.InternalServerErrorWithMessage(err, "could not read body")
+	}
+	if err := json.Unmarshal(buf, &s); err != nil {
+		return false, apimiddleware.InternalServerErrorWithMessage(err, "could not read slot from body")
+	}
+	slot, err := strconv.ParseUint(s.Message.Slot, 10, 64)
+	if err != nil {
+		return false, apimiddleware.InternalServerErrorWithMessage(err, "slot is not an unsigned integer")
+	}
+	currentEpoch := slots.ToEpoch(types.Slot(slot))
+	if currentEpoch < params.BeaconConfig().AltairForkEpoch {
+		endpoint.PostRequest = &signedBeaconBlockContainerJson{}
+	} else if currentEpoch < params.BeaconConfig().BellatrixForkEpoch {
+		endpoint.PostRequest = &signedBeaconBlockAltairContainerJson{}
+	} else {
+		endpoint.PostRequest = &signedBlindedBeaconBlockBellatrixContainerJson{}
+	}
+	req.Body = ioutil.NopCloser(bytes.NewBuffer(buf))
+	return true, nil
+}
+
+// In preparePublishedBlindedBlock we transform the PostRequest.
+// gRPC expects either an XXX_block field in the JSON object, but we have a message field at this point.
+// We do a simple conversion depending on the type of endpoint.PostRequest
+// (which was filled out previously in setInitialPublishBlockPostRequest).
+func preparePublishedBlindedBlock(endpoint *apimiddleware.Endpoint, _ http.ResponseWriter, _ *http.Request) apimiddleware.ErrorJson {
+	if block, ok := endpoint.PostRequest.(*signedBeaconBlockContainerJson); ok {
+		// Prepare post request that can be properly decoded on gRPC side.
+		actualPostReq := &phase0PublishBlockRequestJson{
+			Phase0Block: block.Message,
+			Signature:   block.Signature,
+		}
+		endpoint.PostRequest = actualPostReq
+		return nil
+	}
+	if block, ok := endpoint.PostRequest.(*signedBeaconBlockAltairContainerJson); ok {
+		// Prepare post request that can be properly decoded on gRPC side.
+		actualPostReq := &altairPublishBlockRequestJson{
+			AltairBlock: block.Message,
+			Signature:   block.Signature,
+		}
+		endpoint.PostRequest = actualPostReq
+		return nil
+	}
+	if block, ok := endpoint.PostRequest.(*signedBlindedBeaconBlockBellatrixContainerJson); ok {
+		// Prepare post request that can be properly decoded on gRPC side.
+		actualPostReq := &bellatrixPublishBlindedBlockRequestJson{
+			BellatrixBlock: block.Message,
+			Signature:      block.Signature,
+		}
+		endpoint.PostRequest = actualPostReq
+		return nil
+	}
+	return apimiddleware.InternalServerError(errors.New("unsupported block type"))
+}
+
 type tempSyncCommitteesResponseJson struct {
 	Data *tempSyncCommitteeValidatorsJson `json:"data"`
 }
@@ -341,7 +420,8 @@ func serializeV2Block(response interface{}) (apimiddleware.RunDefault, []byte, a
 	}
 
 	var actualRespContainer interface{}
-	if strings.EqualFold(respContainer.Version, strings.ToLower(ethpbv2.Version_PHASE0.String())) {
+	switch {
+	case strings.EqualFold(respContainer.Version, strings.ToLower(ethpbv2.Version_PHASE0.String())):
 		actualRespContainer = &phase0BlockResponseJson{
 			Version: respContainer.Version,
 			Data: &signedBeaconBlockContainerJson{
@@ -349,7 +429,7 @@ func serializeV2Block(response interface{}) (apimiddleware.RunDefault, []byte, a
 				Signature: respContainer.Data.Signature,
 			},
 		}
-	} else if strings.EqualFold(respContainer.Version, strings.ToLower(ethpbv2.Version_ALTAIR.String())) {
+	case strings.EqualFold(respContainer.Version, strings.ToLower(ethpbv2.Version_ALTAIR.String())):
 		actualRespContainer = &altairBlockResponseJson{
 			Version: respContainer.Version,
 			Data: &signedBeaconBlockAltairContainerJson{
@@ -357,7 +437,7 @@ func serializeV2Block(response interface{}) (apimiddleware.RunDefault, []byte, a
 				Signature: respContainer.Data.Signature,
 			},
 		}
-	} else if strings.EqualFold(respContainer.Version, strings.ToLower(ethpbv2.Version_BELLATRIX.String())) {
+	case strings.EqualFold(respContainer.Version, strings.ToLower(ethpbv2.Version_BELLATRIX.String())):
 		actualRespContainer = &bellatrixBlockResponseJson{
 			Version: respContainer.Version,
 			Data: &signedBeaconBlockBellatrixContainerJson{
@@ -365,7 +445,7 @@ func serializeV2Block(response interface{}) (apimiddleware.RunDefault, []byte, a
 				Signature: respContainer.Data.Signature,
 			},
 		}
-	} else {
+	default:
 		return false, nil, apimiddleware.InternalServerError(fmt.Errorf("unsupported block version '%s'", respContainer.Version))
 	}
 
@@ -440,6 +520,11 @@ type bellatrixProduceBlockResponseJson struct {
 	Data    *beaconBlockBellatrixJson `json:"data"`
 }
 
+type bellatrixProduceBlindedBlockResponseJson struct {
+	Version string                           `json:"version"`
+	Data    *blindedBeaconBlockBellatrixJson `json:"data"`
+}
+
 func serializeProducedV2Block(response interface{}) (apimiddleware.RunDefault, []byte, apimiddleware.ErrorJson) {
 	respContainer, ok := response.(*produceBlockResponseV2Json)
 	if !ok {
@@ -447,22 +532,57 @@ func serializeProducedV2Block(response interface{}) (apimiddleware.RunDefault, [
 	}
 
 	var actualRespContainer interface{}
-	if strings.EqualFold(respContainer.Version, strings.ToLower(ethpbv2.Version_PHASE0.String())) {
+	switch {
+	case strings.EqualFold(respContainer.Version, strings.ToLower(ethpbv2.Version_PHASE0.String())):
 		actualRespContainer = &phase0ProduceBlockResponseJson{
 			Version: respContainer.Version,
 			Data:    respContainer.Data.Phase0Block,
 		}
-	} else if strings.EqualFold(respContainer.Version, strings.ToLower(ethpbv2.Version_ALTAIR.String())) {
+	case strings.EqualFold(respContainer.Version, strings.ToLower(ethpbv2.Version_ALTAIR.String())):
 		actualRespContainer = &altairProduceBlockResponseJson{
 			Version: respContainer.Version,
 			Data:    respContainer.Data.AltairBlock,
 		}
-	} else if strings.EqualFold(respContainer.Version, strings.ToLower(ethpbv2.Version_BELLATRIX.String())) {
+	case strings.EqualFold(respContainer.Version, strings.ToLower(ethpbv2.Version_BELLATRIX.String())):
 		actualRespContainer = &bellatrixProduceBlockResponseJson{
 			Version: respContainer.Version,
 			Data:    respContainer.Data.BellatrixBlock,
 		}
-	} else {
+	default:
+		return false, nil, apimiddleware.InternalServerError(fmt.Errorf("unsupported block version '%s'", respContainer.Version))
+	}
+
+	j, err := json.Marshal(actualRespContainer)
+	if err != nil {
+		return false, nil, apimiddleware.InternalServerErrorWithMessage(err, "could not marshal response")
+	}
+	return false, j, nil
+}
+
+func serializeProducedBlindedBlock(response interface{}) (apimiddleware.RunDefault, []byte, apimiddleware.ErrorJson) {
+	respContainer, ok := response.(*produceBlindedBlockResponseJson)
+	if !ok {
+		return false, nil, apimiddleware.InternalServerError(errors.New("container is not of the correct type"))
+	}
+
+	var actualRespContainer interface{}
+	switch {
+	case strings.EqualFold(respContainer.Version, strings.ToLower(ethpbv2.Version_PHASE0.String())):
+		actualRespContainer = &phase0ProduceBlockResponseJson{
+			Version: respContainer.Version,
+			Data:    respContainer.Data.Phase0Block,
+		}
+	case strings.EqualFold(respContainer.Version, strings.ToLower(ethpbv2.Version_ALTAIR.String())):
+		actualRespContainer = &altairProduceBlockResponseJson{
+			Version: respContainer.Version,
+			Data:    respContainer.Data.AltairBlock,
+		}
+	case strings.EqualFold(respContainer.Version, strings.ToLower(ethpbv2.Version_BELLATRIX.String())):
+		actualRespContainer = &bellatrixProduceBlindedBlockResponseJson{
+			Version: respContainer.Version,
+			Data:    respContainer.Data.BellatrixBlock,
+		}
+	default:
 		return false, nil, apimiddleware.InternalServerError(fmt.Errorf("unsupported block version '%s'", respContainer.Version))
 	}
 

beacon-chain/rpc/apimiddleware/custom_hooks_test.go

@@ -468,6 +468,112 @@ func TestPreparePublishedBlock(t *testing.T) {
 	})
 }
 
+func TestSetInitialPublishBlindedBlockPostRequest(t *testing.T) {
+	params.SetupTestConfigCleanup(t)
+	cfg := params.BeaconConfig()
+	cfg.BellatrixForkEpoch = params.BeaconConfig().AltairForkEpoch + 1
+	params.OverrideBeaconConfig(cfg)
+
+	endpoint := &apimiddleware.Endpoint{}
+	s := struct {
+		Message struct {
+			Slot string
+		}
+	}{}
+	t.Run("Phase 0", func(t *testing.T) {
+		s.Message = struct{ Slot string }{Slot: "0"}
+		j, err := json.Marshal(s)
+		require.NoError(t, err)
+		var body bytes.Buffer
+		_, err = body.Write(j)
+		require.NoError(t, err)
+		request := httptest.NewRequest("POST", "http://foo.example", &body)
+		runDefault, errJson := setInitialPublishBlindedBlockPostRequest(endpoint, nil, request)
+		require.Equal(t, true, errJson == nil)
+		assert.Equal(t, apimiddleware.RunDefault(true), runDefault)
+		assert.Equal(t, reflect.TypeOf(signedBeaconBlockContainerJson{}).Name(), reflect.Indirect(reflect.ValueOf(endpoint.PostRequest)).Type().Name())
+	})
+	t.Run("Altair", func(t *testing.T) {
+		slot, err := slots.EpochStart(params.BeaconConfig().AltairForkEpoch)
+		require.NoError(t, err)
+		s.Message = struct{ Slot string }{Slot: strconv.FormatUint(uint64(slot), 10)}
+		j, err := json.Marshal(s)
+		require.NoError(t, err)
+		var body bytes.Buffer
+		_, err = body.Write(j)
+		require.NoError(t, err)
+		request := httptest.NewRequest("POST", "http://foo.example", &body)
+		runDefault, errJson := setInitialPublishBlindedBlockPostRequest(endpoint, nil, request)
+		require.Equal(t, true, errJson == nil)
+		assert.Equal(t, apimiddleware.RunDefault(true), runDefault)
+		assert.Equal(t, reflect.TypeOf(signedBeaconBlockAltairContainerJson{}).Name(), reflect.Indirect(reflect.ValueOf(endpoint.PostRequest)).Type().Name())
+	})
+	t.Run("Bellatrix", func(t *testing.T) {
+		slot, err := slots.EpochStart(params.BeaconConfig().BellatrixForkEpoch)
+		require.NoError(t, err)
+		s.Message = struct{ Slot string }{Slot: strconv.FormatUint(uint64(slot), 10)}
+		j, err := json.Marshal(s)
+		require.NoError(t, err)
+		var body bytes.Buffer
+		_, err = body.Write(j)
+		require.NoError(t, err)
+		request := httptest.NewRequest("POST", "http://foo.example", &body)
+		runDefault, errJson := setInitialPublishBlindedBlockPostRequest(endpoint, nil, request)
+		require.Equal(t, true, errJson == nil)
+		assert.Equal(t, apimiddleware.RunDefault(true), runDefault)
+		assert.Equal(t, reflect.TypeOf(signedBlindedBeaconBlockBellatrixContainerJson{}).Name(), reflect.Indirect(reflect.ValueOf(endpoint.PostRequest)).Type().Name())
+	})
+}
+
+func TestPreparePublishedBlindedBlock(t *testing.T) {
+	t.Run("Phase 0", func(t *testing.T) {
+		endpoint := &apimiddleware.Endpoint{
+			PostRequest: &signedBeaconBlockContainerJson{
+				Message: &beaconBlockJson{
+					Body: &beaconBlockBodyJson{},
+				},
+			},
+		}
+		errJson := preparePublishedBlindedBlock(endpoint, nil, nil)
+		require.Equal(t, true, errJson == nil)
+		_, ok := endpoint.PostRequest.(*phase0PublishBlockRequestJson)
+		assert.Equal(t, true, ok)
+	})
+
+	t.Run("Altair", func(t *testing.T) {
+		endpoint := &apimiddleware.Endpoint{
+			PostRequest: &signedBeaconBlockAltairContainerJson{
+				Message: &beaconBlockAltairJson{
+					Body: &beaconBlockBodyAltairJson{},
+				},
+			},
+		}
+		errJson := preparePublishedBlindedBlock(endpoint, nil, nil)
+		require.Equal(t, true, errJson == nil)
+		_, ok := endpoint.PostRequest.(*altairPublishBlockRequestJson)
+		assert.Equal(t, true, ok)
+	})
+
+	t.Run("Bellatrix", func(t *testing.T) {
+		endpoint := &apimiddleware.Endpoint{
+			PostRequest: &signedBlindedBeaconBlockBellatrixContainerJson{
+				Message: &blindedBeaconBlockBellatrixJson{
+					Body: &blindedBeaconBlockBodyBellatrixJson{},
+				},
+			},
+		}
+		errJson := preparePublishedBlindedBlock(endpoint, nil, nil)
+		require.Equal(t, true, errJson == nil)
+		_, ok := endpoint.PostRequest.(*bellatrixPublishBlindedBlockRequestJson)
+		assert.Equal(t, true, ok)
+	})
+
+	t.Run("unsupported block type", func(t *testing.T) {
+		errJson := preparePublishedBlock(&apimiddleware.Endpoint{}, nil, nil)
+		assert.Equal(t, true, strings.Contains(errJson.Msg(), "unsupported block type"))
+	})
+}
+
 func TestPrepareValidatorAggregates(t *testing.T) {
 	body := &tempSyncCommitteesResponseJson{
 		Data: &tempSyncCommitteeValidatorsJson{
@@ -779,3 +885,113 @@ func TestSerializeProducedV2Block(t *testing.T) {
 		assert.Equal(t, true, strings.Contains(errJson.Msg(), "unsupported block version"))
 	})
 }
+
+func TestSerializeProduceBlindedBlock(t *testing.T) {
+	t.Run("Phase 0", func(t *testing.T) {
+		response := &produceBlindedBlockResponseJson{
+			Version: ethpbv2.Version_PHASE0.String(),
+			Data: &blindedBeaconBlockContainerJson{
+				Phase0Block: &beaconBlockJson{
+					Slot:          "1",
+					ProposerIndex: "1",
+					ParentRoot:    "root",
+					StateRoot:     "root",
+					Body:          &beaconBlockBodyJson{},
+				},
+				AltairBlock: nil,
+			},
+		}
+		runDefault, j, errJson := serializeProducedBlindedBlock(response)
+		require.Equal(t, nil, errJson)
+		require.Equal(t, apimiddleware.RunDefault(false), runDefault)
+		require.NotNil(t, j)
+		resp := &phase0ProduceBlockResponseJson{}
+		require.NoError(t, json.Unmarshal(j, resp))
+		require.NotNil(t, resp.Data)
+		require.NotNil(t, resp.Data)
+		beaconBlock := resp.Data
+		assert.Equal(t, "1", beaconBlock.Slot)
+		assert.Equal(t, "1", beaconBlock.ProposerIndex)
+		assert.Equal(t, "root", beaconBlock.ParentRoot)
+		assert.Equal(t, "root", beaconBlock.StateRoot)
+		require.NotNil(t, beaconBlock.Body)
+	})
+
+	t.Run("Altair", func(t *testing.T) {
+		response := &produceBlindedBlockResponseJson{
+			Version: ethpbv2.Version_ALTAIR.String(),
+			Data: &blindedBeaconBlockContainerJson{
+				AltairBlock: &beaconBlockAltairJson{
+					Slot:          "1",
+					ProposerIndex: "1",
+					ParentRoot:    "root",
+					StateRoot:     "root",
+					Body:          &beaconBlockBodyAltairJson{},
+				},
+			},
+		}
+		runDefault, j, errJson := serializeProducedBlindedBlock(response)
+		require.Equal(t, nil, errJson)
+		require.Equal(t, apimiddleware.RunDefault(false), runDefault)
+		require.NotNil(t, j)
+		resp := &altairProduceBlockResponseJson{}
+		require.NoError(t, json.Unmarshal(j, resp))
+		require.NotNil(t, resp.Data)
+		require.NotNil(t, resp.Data)
+		beaconBlock := resp.Data
+		assert.Equal(t, "1", beaconBlock.Slot)
+		assert.Equal(t, "1", beaconBlock.ProposerIndex)
+		assert.Equal(t, "root", beaconBlock.ParentRoot)
+		assert.Equal(t, "root", beaconBlock.StateRoot)
+		require.NotNil(t, beaconBlock.Body)
+	})
+
+	t.Run("Bellatrix", func(t *testing.T) {
+		response := &produceBlindedBlockResponseJson{
+			Version: ethpbv2.Version_BELLATRIX.String(),
+			Data: &blindedBeaconBlockContainerJson{
+				BellatrixBlock: &blindedBeaconBlockBellatrixJson{
+					Slot:          "1",
+					ProposerIndex: "1",
+					ParentRoot:    "root",
+					StateRoot:     "root",
+					Body:          &blindedBeaconBlockBodyBellatrixJson{},
+				},
+			},
+		}
+		runDefault, j, errJson := serializeProducedBlindedBlock(response)
+		require.Equal(t, nil, errJson)
+		require.Equal(t, apimiddleware.RunDefault(false), runDefault)
+		require.NotNil(t, j)
+		resp := &bellatrixProduceBlindedBlockResponseJson{}
+		require.NoError(t, json.Unmarshal(j, resp))
+		require.NotNil(t, resp.Data)
+		require.NotNil(t, resp.Data)
+		beaconBlock := resp.Data
+		assert.Equal(t, "1", beaconBlock.Slot)
+		assert.Equal(t, "1", beaconBlock.ProposerIndex)
+		assert.Equal(t, "root", beaconBlock.ParentRoot)
+		assert.Equal(t, "root", beaconBlock.StateRoot)
+		require.NotNil(t, beaconBlock.Body)
+	})
+
+	t.Run("incorrect response type", func(t *testing.T) {
+		response := &types.Empty{}
+		runDefault, j, errJson := serializeProducedV2Block(response)
+		require.Equal(t, apimiddleware.RunDefault(false), runDefault)
+		require.Equal(t, 0, len(j))
+		require.NotNil(t, errJson)
+		assert.Equal(t, true, strings.Contains(errJson.Msg(), "container is not of the correct type"))
+	})
+
+	t.Run("unsupported block version", func(t *testing.T) {
+		response := &produceBlockResponseV2Json{
+			Version: "unsupported",
+		}
+		runDefault, j, errJson := serializeProducedV2Block(response)
+		require.Equal(t, apimiddleware.RunDefault(false), runDefault)
+		require.Equal(t, 0, len(j))
+		require.NotNil(t, errJson)
+		assert.Equal(t, true, strings.Contains(errJson.Msg(), "unsupported block version"))
+	})
+}

beacon-chain/rpc/apimiddleware/endpoint_factory.go

@@ -28,6 +28,7 @@ func (_ *BeaconEndpointFactory) Paths() []string {
 		"/eth/v1/beacon/headers",
 		"/eth/v1/beacon/headers/{block_id}",
 		"/eth/v1/beacon/blocks",
+		"/eth/v1/beacon/blinded_blocks",
 		"/eth/v1/beacon/blocks/{block_id}",
 		"/eth/v2/beacon/blocks/{block_id}",
 		"/eth/v1/beacon/blocks/{block_id}/root",
@@ -58,6 +59,7 @@ func (_ *BeaconEndpointFactory) Paths() []string {
 		"/eth/v1/validator/duties/sync/{epoch}",
 		"/eth/v1/validator/blocks/{slot}",
 		"/eth/v2/validator/blocks/{slot}",
+		"/eth/v1/validator/blinded_blocks/{slot}",
 		"/eth/v1/validator/attestation_data",
 		"/eth/v1/validator/aggregate_attestation",
 		"/eth/v1/validator/beacon_committee_subscriptions",
@@ -108,6 +110,11 @@ func (_ *BeaconEndpointFactory) Create(path string) (*apimiddleware.Endpoint, er
 			OnPreDeserializeRequestBodyIntoContainer:  setInitialPublishBlockPostRequest,
 			OnPostDeserializeRequestBodyIntoContainer: preparePublishedBlock,
 		}
+	case "/eth/v1/beacon/blinded_blocks":
+		endpoint.Hooks = apimiddleware.HookCollection{
+			OnPreDeserializeRequestBodyIntoContainer:  setInitialPublishBlindedBlockPostRequest,
+			OnPostDeserializeRequestBodyIntoContainer: preparePublishedBlindedBlock,
+		}
 	case "/eth/v1/beacon/blocks/{block_id}":
 		endpoint.GetResponse = &blockResponseJson{}
 		endpoint.CustomHandlers = []apimiddleware.CustomHandler{handleGetBeaconBlockSSZ}
@@ -214,6 +221,13 @@ func (_ *BeaconEndpointFactory) Create(path string) (*apimiddleware.Endpoint, er
 		endpoint.Hooks = apimiddleware.HookCollection{
 			OnPreSerializeMiddlewareResponseIntoJson: serializeProducedV2Block,
 		}
+	case "/eth/v1/validator/blinded_blocks/{slot}":
+		endpoint.GetResponse = &produceBlindedBlockResponseJson{}
+		endpoint.RequestURLLiterals = []string{"slot"}
+		endpoint.RequestQueryParams = []apimiddleware.QueryParam{{Name: "randao_reveal", Hex: true}, {Name: "graffiti", Hex: true}}
+		endpoint.Hooks = apimiddleware.HookCollection{
+			OnPreSerializeMiddlewareResponseIntoJson: serializeProducedBlindedBlock,
+		}
 	case "/eth/v1/validator/attestation_data":
 		endpoint.GetResponse = &produceAttestationDataResponseJson{}
 		endpoint.RequestQueryParams = []apimiddleware.QueryParam{{Name: "slot"}, {Name: "committee_index"}}

beacon-chain/rpc/apimiddleware/structs.go

@@ -270,6 +270,12 @@ type produceBlockResponseV2Json struct {
 	Data    *beaconBlockContainerV2Json `json:"data"`
 }
 
+// produceBlindedBlockResponseJson is used in /v1/validator/blinded_blocks/{slot} API endpoint.
+type produceBlindedBlockResponseJson struct {
+	Version string                           `json:"version"`
+	Data    *blindedBeaconBlockContainerJson `json:"data"`
+}
+
 // produceAttestationDataResponseJson is used in /validator/attestation_data API endpoint.
 type produceAttestationDataResponseJson struct {
 	Data *attestationDataJson `json:"data"`
@@ -371,6 +377,12 @@ type beaconBlockContainerV2Json struct {
 	BellatrixBlock *beaconBlockBellatrixJson `json:"bellatrix_block"`
 }
 
+type blindedBeaconBlockContainerJson struct {
+	Phase0Block    *beaconBlockJson                 `json:"phase0_block"`
+	AltairBlock    *beaconBlockAltairJson           `json:"altair_block"`
+	BellatrixBlock *blindedBeaconBlockBellatrixJson `json:"bellatrix_block"`
+}
+
 type signedBeaconBlockAltairContainerJson struct {
 	Message   *beaconBlockAltairJson `json:"message"`
 	Signature string                 `json:"signature" hex:"true"`
@@ -381,6 +393,11 @@ type signedBeaconBlockBellatrixContainerJson struct {
 	Signature string                    `json:"signature" hex:"true"`
 }
 
+type signedBlindedBeaconBlockBellatrixContainerJson struct {
+	Message   *blindedBeaconBlockBellatrixJson `json:"message"`
+	Signature string                           `json:"signature" hex:"true"`
+}
+
 type beaconBlockAltairJson struct {
 	Slot          string                     `json:"slot"`
 	ProposerIndex string                     `json:"proposer_index"`
@@ -397,6 +414,14 @@ type beaconBlockBellatrixJson struct {
 	Body          *beaconBlockBodyBellatrixJson `json:"body"`
 }
 
+type blindedBeaconBlockBellatrixJson struct {
+	Slot          string                               `json:"slot"`
+	ProposerIndex string                               `json:"proposer_index"`
+	ParentRoot    string                               `json:"parent_root" hex:"true"`
+	StateRoot     string                               `json:"state_root" hex:"true"`
+	Body          *blindedBeaconBlockBodyBellatrixJson `json:"body"`
+}
+
 type beaconBlockBodyAltairJson struct {
 	RandaoReveal      string                     `json:"randao_reveal" hex:"true"`
 	Eth1Data          *eth1DataJson              `json:"eth1_data"`
@@ -422,6 +447,19 @@ type beaconBlockBodyBellatrixJson struct {
 	ExecutionPayload  *executionPayloadJson      `json:"execution_payload"`
 }
 
+type blindedBeaconBlockBodyBellatrixJson struct {
+	RandaoReveal           string                      `json:"randao_reveal" hex:"true"`
+	Eth1Data               *eth1DataJson               `json:"eth1_data"`
+	Graffiti               string                      `json:"graffiti" hex:"true"`
+	ProposerSlashings      []*proposerSlashingJson     `json:"proposer_slashings"`
+	AttesterSlashings      []*attesterSlashingJson     `json:"attester_slashings"`
+	Attestations           []*attestationJson          `json:"attestations"`
+	Deposits               []*depositJson              `json:"deposits"`
+	VoluntaryExits         []*signedVoluntaryExitJson  `json:"voluntary_exits"`
+	SyncAggregate          *syncAggregateJson          `json:"sync_aggregate"`
+	ExecutionPayloadHeader *executionPayloadHeaderJson `json:"execution_payload"`
+}
+
 type executionPayloadJson struct {
 	ParentHash    string   `json:"parent_hash" hex:"true"`
 	FeeRecipient  string   `json:"fee_recipient" hex:"true"`
@@ -434,7 +472,7 @@ type executionPayloadJson struct {
 	GasUsed       string   `json:"gas_used"`
 	TimeStamp     string   `json:"timestamp"`
 	ExtraData     string   `json:"extra_data" hex:"true"`
-	BaseFeePerGas string   `json:"base_fee_per_gas" hex:"true"`
+	BaseFeePerGas string   `json:"base_fee_per_gas" uint256:"true"`
 	BlockHash     string   `json:"block_hash" hex:"true"`
 	Transactions  []string `json:"transactions" hex:"true"`
 }

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

@@ -37,6 +37,7 @@ go_library(
         "//beacon-chain/state/v1:go_default_library",
         "//beacon-chain/sync:go_default_library",
         "//config/features:go_default_library",
+        "//config/fieldparams:go_default_library",
         "//config/params:go_default_library",
         "//crypto/bls:go_default_library",
         "//encoding/bytesutil:go_default_library",
@@ -94,6 +95,7 @@ go_test(
         "//config/params:go_default_library",
         "//crypto/bls:go_default_library",
         "//encoding/bytesutil:go_default_library",
+        "//encoding/ssz:go_default_library",
         "//proto/eth/service:go_default_library",
         "//proto/eth/v1:go_default_library",
         "//proto/eth/v2:go_default_library",

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

@@ -13,6 +13,7 @@ import (
 	"github.com/prysmaticlabs/prysm/beacon-chain/core/helpers"
 	"github.com/prysmaticlabs/prysm/beacon-chain/db/filters"
 	rpchelpers "github.com/prysmaticlabs/prysm/beacon-chain/rpc/eth/helpers"
+	fieldparams "github.com/prysmaticlabs/prysm/config/fieldparams"
 	"github.com/prysmaticlabs/prysm/config/params"
 	"github.com/prysmaticlabs/prysm/encoding/bytesutil"
 	ethpbv1 "github.com/prysmaticlabs/prysm/proto/eth/v1"
@@ -201,59 +202,58 @@ func (bs *Server) SubmitBlock(ctx context.Context, req *ethpbv2.SignedBeaconBloc
 	ctx, span := trace.StartSpan(ctx, "beacon.SubmitBlock")
 	defer span.End()
 
-	var wsb block.SignedBeaconBlock
-	var err error
-	var v1alpha1Blk interface{}
-
-	switch blk := req.Message.(type) {
-	case *ethpbv2.SignedBeaconBlockContainerV2_Phase0Block:
-		v1alpha1Blk, err = migration.V1ToV1Alpha1SignedBlock(&ethpbv1.SignedBeaconBlock{Block: blk.Phase0Block, Signature: req.Signature})
-		if err != nil {
-			return nil, status.Errorf(codes.InvalidArgument, "Could not convert block to v1 block: %v", err)
+	phase0BlkContainer, ok := req.Message.(*ethpbv2.SignedBeaconBlockContainerV2_Phase0Block)
+	if ok {
+		if err := bs.submitPhase0Block(ctx, phase0BlkContainer.Phase0Block, req.Signature); err != nil {
+			return nil, err
 		}
-		wsb, err = wrapper.WrappedSignedBeaconBlock(v1alpha1Blk)
-	case *ethpbv2.SignedBeaconBlockContainerV2_AltairBlock:
-		v1alpha1Blk, err = migration.AltairToV1Alpha1SignedBlock(&ethpbv2.SignedBeaconBlockAltair{Message: blk.AltairBlock, Signature: req.Signature})
-		if err != nil {
-			return nil, status.Errorf(codes.InvalidArgument, "Could not convert block to v1 block: %v", err)
+	}
+	altairBlkContainer, ok := req.Message.(*ethpbv2.SignedBeaconBlockContainerV2_AltairBlock)
+	if ok {
+		if err := bs.submitAltairBlock(ctx, altairBlkContainer.AltairBlock, req.Signature); err != nil {
+			return nil, err
 		}
-		wsb, err = wrapper.WrappedSignedBeaconBlock(v1alpha1Blk)
-	case *ethpbv2.SignedBeaconBlockContainerV2_BellatrixBlock:
-		v1alpha1Blk, err = migration.BellatrixToV1Alpha1SignedBlock(&ethpbv2.SignedBeaconBlockBellatrix{Message: blk.BellatrixBlock, Signature: req.Signature})
-		if err != nil {
-			return nil, status.Errorf(codes.InvalidArgument, "Could not convert block to v1 block: %v", err)
+	}
+	bellatrixBlkContainer, ok := req.Message.(*ethpbv2.SignedBeaconBlockContainerV2_BellatrixBlock)
+	if ok {
+		if err := bs.submitBellatrixBlock(ctx, bellatrixBlkContainer.BellatrixBlock, req.Signature); err != nil {
+			return nil, err
+		}
+	}
+	return &emptypb.Empty{}, nil
+}
+
+// SubmitBlindedBlock instructs the beacon node to use the components of the `SignedBlindedBeaconBlock` to construct
+// and publish a `SignedBeaconBlock` by swapping out the `transactions_root` for the corresponding full list of `transactions`.
+// The beacon node should broadcast a newly constructed `SignedBeaconBlock` to the beacon network,
+// to be included in the beacon chain. The beacon node is not required to validate the signed
+// `BeaconBlock`, and a successful response (20X) only indicates that the broadcast has been
+// successful. The beacon node is expected to integrate the new block into its state, and
+// therefore validate the block internally, however blocks which fail the validation are still
+// broadcast but a different status code is returned (202).
+func (bs *Server) SubmitBlindedBlock(ctx context.Context, req *ethpbv2.SignedBlindedBeaconBlockContainer) (*emptypb.Empty, error) {
+	ctx, span := trace.StartSpan(ctx, "beacon.SubmitBlindedBlock")
+	defer span.End()
+
+	bellatrixBlkContainer, ok := req.Message.(*ethpbv2.SignedBlindedBeaconBlockContainer_BellatrixBlock)
+	if ok {
+		if err := bs.submitBlindedBellatrixBlock(ctx, bellatrixBlkContainer.BellatrixBlock, req.Signature); err != nil {
+			return nil, err
 		}
-		wsb, err = wrapper.WrappedSignedBeaconBlock(v1alpha1Blk)
-	default:
-		return nil, status.Errorf(codes.InvalidArgument, "Unsupported block type %T", req.Message)
 	}
 
-	if err != nil {
-		return nil, status.Errorf(codes.InvalidArgument, "Could not wrap beacon block: %v", err)
+	// At the end we check forks that don't have blinded blocks.
+	phase0BlkContainer, ok := req.Message.(*ethpbv2.SignedBlindedBeaconBlockContainer_Phase0Block)
+	if ok {
+		if err := bs.submitPhase0Block(ctx, phase0BlkContainer.Phase0Block, req.Signature); err != nil {
+			return nil, err
+		}
 	}
-
-	root, err := wsb.Block().HashTreeRoot()
-	if err != nil {
-		return nil, status.Errorf(codes.InvalidArgument, "Could not tree hash block: %v", err)
-	}
-
-	// Do not block proposal critical path with debug logging or block feed updates.
-	defer func() {
-		log.WithField("blockRoot", fmt.Sprintf("%#x", bytesutil.Trunc(root[:]))).Debugf(
-			"Block proposal received via RPC")
-		bs.BlockNotifier.BlockFeed().Send(&feed.Event{
-			Type: blockfeed.ReceivedBlock,
-			Data: &blockfeed.ReceivedBlockData{SignedBlock: wsb, IsOptimistic: false},
-		})
-	}()
-
-	// Broadcast the new block to the network.
-	if err := bs.Broadcaster.Broadcast(ctx, wsb.Proto()); err != nil {
-		return nil, status.Errorf(codes.Internal, "Could not broadcast block: %v", err)
-	}
-
-	if err := bs.BlockReceiver.ReceiveBlock(ctx, wsb, root); err != nil {
-		return nil, status.Errorf(codes.Internal, "Could not process beacon block: %v", err)
+	altairBlkContainer, ok := req.Message.(*ethpbv2.SignedBlindedBeaconBlockContainer_AltairBlock)
+	if ok {
+		if err := bs.submitAltairBlock(ctx, altairBlkContainer.AltairBlock, req.Signature); err != nil {
+			return nil, err
+		}
 	}
 
 	return &emptypb.Empty{}, nil
@@ -706,3 +706,100 @@ func handleGetBlockError(blk block.SignedBeaconBlock, err error) error {
 	}
 	return nil
 }
+
+func (bs *Server) submitPhase0Block(ctx context.Context, phase0Blk *ethpbv1.BeaconBlock, sig []byte) error {
+	v1alpha1Blk, err := migration.V1ToV1Alpha1SignedBlock(&ethpbv1.SignedBeaconBlock{Block: phase0Blk, Signature: sig})
+	if err != nil {
+		return status.Errorf(codes.InvalidArgument, "Could not convert block to v1 block")
+	}
+	wrappedPhase0Blk, err := wrapper.WrappedSignedBeaconBlock(v1alpha1Blk)
+	if err != nil {
+		return status.Errorf(codes.InvalidArgument, "Could not prepare block")
+	}
+	root, err := phase0Blk.HashTreeRoot()
+	if err != nil {
+		return status.Errorf(codes.InvalidArgument, "Could not tree hash block: %v", err)
+	}
+
+	return bs.submitBlock(ctx, root, wrappedPhase0Blk)
+}
+
+func (bs *Server) submitAltairBlock(ctx context.Context, altairBlk *ethpbv2.BeaconBlockAltair, sig []byte) error {
+	v1alpha1Blk, err := migration.AltairToV1Alpha1SignedBlock(&ethpbv2.SignedBeaconBlockAltair{Message: altairBlk, Signature: sig})
+	if err != nil {
+		return status.Errorf(codes.InvalidArgument, "Could not convert block to v1 block")
+	}
+	wrappedAltairBlk, err := wrapper.WrappedSignedBeaconBlock(v1alpha1Blk)
+	if err != nil {
+		return status.Errorf(codes.InvalidArgument, "Could not prepare block")
+	}
+
+	root, err := altairBlk.HashTreeRoot()
+	if err != nil {
+		return status.Errorf(codes.InvalidArgument, "Could not tree hash block: %v", err)
+	}
+
+	return bs.submitBlock(ctx, root, wrappedAltairBlk)
+}
+
+func (bs *Server) submitBellatrixBlock(ctx context.Context, bellatrixBlk *ethpbv2.BeaconBlockBellatrix, sig []byte) error {
+	v1alpha1Blk, err := migration.BellatrixToV1Alpha1SignedBlock(&ethpbv2.SignedBeaconBlockBellatrix{Message: bellatrixBlk, Signature: sig})
+	if err != nil {
+		return status.Errorf(codes.InvalidArgument, "Could not convert block to v1 block")
+	}
+	wrappedBellatrixBlk, err := wrapper.WrappedSignedBeaconBlock(v1alpha1Blk)
+	if err != nil {
+		return status.Errorf(codes.InvalidArgument, "Could not prepare block")
+	}
+
+	root, err := bellatrixBlk.HashTreeRoot()
+	if err != nil {
+		return status.Errorf(codes.InvalidArgument, "Could not tree hash block: %v", err)
+	}
+
+	return bs.submitBlock(ctx, root, wrappedBellatrixBlk)
+}
+
+func (bs *Server) submitBlindedBellatrixBlock(ctx context.Context, blindedBellatrixBlk *ethpbv2.BlindedBeaconBlockBellatrix, sig []byte) error {
+	v1alpha1SignedBlk, err := migration.BlindedBellatrixToV1Alpha1SignedBlock(&ethpbv2.SignedBlindedBeaconBlockBellatrix{
+		Message:   blindedBellatrixBlk,
+		Signature: sig,
+	})
+	if err != nil {
+		return status.Errorf(codes.Internal, "Could not get blinded block: %v", err)
+	}
+	wrappedBellatrixSignedBlk, err := wrapper.WrappedSignedBeaconBlock(v1alpha1SignedBlk)
+	if err != nil {
+		return status.Errorf(codes.Internal, "Could not get blinded block: %v", err)
+	}
+
+	root, err := blindedBellatrixBlk.HashTreeRoot()
+	if err != nil {
+		return status.Errorf(codes.InvalidArgument, "Could not tree hash block: %v", err)
+	}
+
+	return bs.submitBlock(ctx, root, wrappedBellatrixSignedBlk)
+}
+
+func (bs *Server) submitBlock(ctx context.Context, blockRoot [fieldparams.RootLength]byte, block block.SignedBeaconBlock) error {
+	// Do not block proposal critical path with debug logging or block feed updates.
+	defer func() {
+		log.WithField("blockRoot", fmt.Sprintf("%#x", bytesutil.Trunc(blockRoot[:]))).Debugf(
+			"Block proposal received via RPC")
+		bs.BlockNotifier.BlockFeed().Send(&feed.Event{
+			Type: blockfeed.ReceivedBlock,
+			Data: &blockfeed.ReceivedBlockData{SignedBlock: block},
+		})
+	}()
+
+	// Broadcast the new block to the network.
+	if err := bs.Broadcaster.Broadcast(ctx, block.Proto()); err != nil {
+		return status.Errorf(codes.Internal, "Could not broadcast block: %v", err)
+	}
+
+	if err := bs.BlockReceiver.ReceiveBlock(ctx, block, blockRoot); err != nil {
+		return status.Errorf(codes.Internal, "Could not process beacon block: %v", err)
+	}
+
+	return nil
+}

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

@@ -11,6 +11,7 @@ import (
 	dbTest "github.com/prysmaticlabs/prysm/beacon-chain/db/testing"
 	mockp2p "github.com/prysmaticlabs/prysm/beacon-chain/p2p/testing"
 	"github.com/prysmaticlabs/prysm/encoding/bytesutil"
+	"github.com/prysmaticlabs/prysm/encoding/ssz"
 	ethpbv1 "github.com/prysmaticlabs/prysm/proto/eth/v1"
 	ethpbv2 "github.com/prysmaticlabs/prysm/proto/eth/v2"
 	"github.com/prysmaticlabs/prysm/proto/migration"
@@ -428,7 +429,7 @@ func TestServer_ListBlockHeaders(t *testing.T) {
 	})
 }
 
-func TestServer_ProposeBlock_OK(t *testing.T) {
+func TestServer_SubmitBlock_OK(t *testing.T) {
 	t.Run("Phase 0", func(t *testing.T) {
 		beaconDB := dbTest.SetupDB(t)
 		ctx := context.Background()
@@ -556,6 +557,140 @@ func TestServer_ProposeBlock_OK(t *testing.T) {
 	})
 }
 
+func TestSubmitBlindedBlock(t *testing.T) {
+	t.Run("Phase 0", func(t *testing.T) {
+		beaconDB := dbTest.SetupDB(t)
+		ctx := context.Background()
+
+		genesis := util.NewBeaconBlock()
+		blk, err := wrapper.WrappedSignedBeaconBlock(genesis)
+		require.NoError(t, err)
+		require.NoError(t, beaconDB.SaveBlock(context.Background(), blk), "Could not save genesis block")
+
+		numDeposits := uint64(64)
+		beaconState, _ := util.DeterministicGenesisState(t, numDeposits)
+		bsRoot, err := beaconState.HashTreeRoot(ctx)
+		require.NoError(t, err)
+		genesisRoot, err := genesis.Block.HashTreeRoot()
+		require.NoError(t, err)
+		require.NoError(t, beaconDB.SaveState(ctx, beaconState, genesisRoot), "Could not save genesis state")
+
+		c := &mock.ChainService{Root: bsRoot[:], State: beaconState}
+		beaconChainServer := &Server{
+			BeaconDB:         beaconDB,
+			BlockReceiver:    c,
+			ChainInfoFetcher: c,
+			BlockNotifier:    c.BlockNotifier(),
+			Broadcaster:      mockp2p.NewTestP2P(t),
+		}
+		req := util.NewBeaconBlock()
+		req.Block.Slot = 5
+		req.Block.ParentRoot = bsRoot[:]
+		v1Block, err := migration.V1Alpha1ToV1SignedBlock(req)
+		require.NoError(t, err)
+		wrapped, err := wrapper.WrappedSignedBeaconBlock(req)
+		require.NoError(t, err)
+		require.NoError(t, beaconDB.SaveBlock(ctx, wrapped))
+		blockReq := &ethpbv2.SignedBlindedBeaconBlockContainer{
+			Message:   &ethpbv2.SignedBlindedBeaconBlockContainer_Phase0Block{Phase0Block: v1Block.Block},
+			Signature: v1Block.Signature,
+		}
+		_, err = beaconChainServer.SubmitBlindedBlock(context.Background(), blockReq)
+		assert.NoError(t, err, "Could not propose block correctly")
+	})
+
+	t.Run("Altair", func(t *testing.T) {
+		beaconDB := dbTest.SetupDB(t)
+		ctx := context.Background()
+
+		genesis := util.NewBeaconBlockAltair()
+		blk, err := wrapper.WrappedSignedBeaconBlock(genesis)
+		require.NoError(t, err)
+		require.NoError(t, beaconDB.SaveBlock(context.Background(), blk), "Could not save genesis block")
+
+		numDeposits := uint64(64)
+		beaconState, _ := util.DeterministicGenesisState(t, numDeposits)
+		bsRoot, err := beaconState.HashTreeRoot(ctx)
+		require.NoError(t, err)
+		genesisRoot, err := genesis.Block.HashTreeRoot()
+		require.NoError(t, err)
+		require.NoError(t, beaconDB.SaveState(ctx, beaconState, genesisRoot), "Could not save genesis state")
+
+		c := &mock.ChainService{Root: bsRoot[:], State: beaconState}
+		beaconChainServer := &Server{
+			BeaconDB:         beaconDB,
+			BlockReceiver:    c,
+			ChainInfoFetcher: c,
+			BlockNotifier:    c.BlockNotifier(),
+			Broadcaster:      mockp2p.NewTestP2P(t),
+		}
+		req := util.NewBeaconBlockAltair()
+		req.Block.Slot = 5
+		req.Block.ParentRoot = bsRoot[:]
+		v2Block, err := migration.V1Alpha1BeaconBlockAltairToV2(req.Block)
+		require.NoError(t, err)
+		wrapped, err := wrapper.WrappedSignedBeaconBlock(genesis)
+		require.NoError(t, err)
+		require.NoError(t, beaconDB.SaveBlock(ctx, wrapped))
+		blockReq := &ethpbv2.SignedBlindedBeaconBlockContainer{
+			Message:   &ethpbv2.SignedBlindedBeaconBlockContainer_AltairBlock{AltairBlock: v2Block},
+			Signature: req.Signature,
+		}
+		_, err = beaconChainServer.SubmitBlindedBlock(context.Background(), blockReq)
+		assert.NoError(t, err, "Could not propose block correctly")
+	})
+
+	t.Run("Bellatrix - OK", func(t *testing.T) {
+		transactions := [][]byte{[]byte("transaction1"), []byte("transaction2")}
+		transactionsRoot, err := ssz.TransactionsRoot(transactions)
+		require.NoError(t, err)
+
+		beaconDB := dbTest.SetupDB(t)
+		ctx := context.Background()
+
+		genesis := util.NewBeaconBlockBellatrix()
+		wrapped, err := wrapper.WrappedSignedBeaconBlock(genesis)
+		require.NoError(t, err)
+		require.NoError(t, beaconDB.SaveBlock(context.Background(), wrapped), "Could not save genesis block")
+
+		numDeposits := uint64(64)
+		beaconState, _ := util.DeterministicGenesisState(t, numDeposits)
+		bsRoot, err := beaconState.HashTreeRoot(ctx)
+		require.NoError(t, err)
+		genesisRoot, err := genesis.Block.HashTreeRoot()
+		require.NoError(t, err)
+		require.NoError(t, beaconDB.SaveState(ctx, beaconState, genesisRoot), "Could not save genesis state")
+
+		c := &mock.ChainService{Root: bsRoot[:], State: beaconState}
+		beaconChainServer := &Server{
+			BeaconDB:         beaconDB,
+			BlockReceiver:    c,
+			ChainInfoFetcher: c,
+			BlockNotifier:    c.BlockNotifier(),
+			Broadcaster:      mockp2p.NewTestP2P(t),
+		}
+
+		blk := util.NewBeaconBlockBellatrix()
+		blk.Block.Slot = 5
+		blk.Block.ParentRoot = bsRoot[:]
+		blk.Block.Body.ExecutionPayload.Transactions = transactions
+		blindedBlk := util.NewBlindedBeaconBlockBellatrix()
+		blindedBlk.Message.Slot = 5
+		blindedBlk.Message.ParentRoot = bsRoot[:]
+		blindedBlk.Message.Body.ExecutionPayloadHeader.TransactionsRoot = transactionsRoot[:]
+		wrapped, err = wrapper.WrappedSignedBeaconBlock(blk)
+		require.NoError(t, err)
+		require.NoError(t, beaconDB.SaveBlock(ctx, wrapped))
+
+		blockReq := &ethpbv2.SignedBlindedBeaconBlockContainer{
+			Message:   &ethpbv2.SignedBlindedBeaconBlockContainer_BellatrixBlock{BellatrixBlock: blindedBlk.Message},
+			Signature: blindedBlk.Signature,
+		}
+		_, err = beaconChainServer.SubmitBlindedBlock(context.Background(), blockReq)
+		assert.NoError(t, err)
+	})
+}
+
 func TestServer_GetBlock(t *testing.T) {
 	beaconDB := dbTest.SetupDB(t)
 	ctx := context.Background()

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

@@ -286,6 +286,7 @@ func (vs *Server) ProduceBlock(ctx context.Context, req *ethpbv1.ProduceBlockReq
 	return &ethpbv1.ProduceBlockResponse{Data: block}, nil
 }
 
+// ProduceBlockV2 requests the beacon node to produce a valid unsigned beacon block, which can then be signed by a proposer and submitted.
 func (vs *Server) ProduceBlockV2(ctx context.Context, req *ethpbv1.ProduceBlockRequest) (*ethpbv2.ProduceBlockResponseV2, error) {
 	_, span := trace.StartSpan(ctx, "validator.ProduceBlockV2")
 	defer span.End()
@@ -347,6 +348,71 @@ func (vs *Server) ProduceBlockV2(ctx context.Context, req *ethpbv1.ProduceBlockR
 	return nil, status.Error(codes.InvalidArgument, "Unsupported block type")
 }
 
+// ProduceBlindedBlock requests the beacon node to produce a valid unsigned blinded beacon block,
+// which can then be signed by a proposer and submitted.
+//
+// Pre-Bellatrix, this endpoint will return a regular block.
+func (vs *Server) ProduceBlindedBlock(ctx context.Context, req *ethpbv1.ProduceBlockRequest) (*ethpbv2.ProduceBlindedBlockResponse, error) {
+	ctx, span := trace.StartSpan(ctx, "validator.ProduceBlindedBlock")
+	defer span.End()
+
+	if err := rpchelpers.ValidateSync(ctx, vs.SyncChecker, vs.HeadFetcher, vs.TimeFetcher); err != nil {
+		// We simply return the error because it's already a gRPC error.
+		return nil, err
+	}
+
+	v1alpha1req := &ethpbalpha.BlockRequest{
+		Slot:         req.Slot,
+		RandaoReveal: req.RandaoReveal,
+		Graffiti:     req.Graffiti,
+	}
+	v1alpha1resp, err := vs.V1Alpha1Server.GetBeaconBlock(ctx, v1alpha1req)
+	if err != nil {
+		// We simply return err because it's already of a gRPC error type.
+		return nil, err
+	}
+	phase0Block, ok := v1alpha1resp.Block.(*ethpbalpha.GenericBeaconBlock_Phase0)
+	if ok {
+		block, err := migration.V1Alpha1ToV1Block(phase0Block.Phase0)
+		if err != nil {
+			return nil, status.Errorf(codes.Internal, "Could not prepare beacon block: %v", err)
+		}
+		return &ethpbv2.ProduceBlindedBlockResponse{
+			Version: ethpbv2.Version_PHASE0,
+			Data: &ethpbv2.BlindedBeaconBlockContainer{
+				Block: &ethpbv2.BlindedBeaconBlockContainer_Phase0Block{Phase0Block: block},
+			},
+		}, nil
+	}
+	altairBlock, ok := v1alpha1resp.Block.(*ethpbalpha.GenericBeaconBlock_Altair)
+	if ok {
+		block, err := migration.V1Alpha1BeaconBlockAltairToV2(altairBlock.Altair)
+		if err != nil {
+			return nil, status.Errorf(codes.Internal, "Could not prepare beacon block: %v", err)
+		}
+		return &ethpbv2.ProduceBlindedBlockResponse{
+			Version: ethpbv2.Version_ALTAIR,
+			Data: &ethpbv2.BlindedBeaconBlockContainer{
+				Block: &ethpbv2.BlindedBeaconBlockContainer_AltairBlock{AltairBlock: block},
+			},
+		}, nil
+	}
+	bellatrixBlock, ok := v1alpha1resp.Block.(*ethpbalpha.GenericBeaconBlock_Bellatrix)
+	if ok {
+		block, err := migration.V1Alpha1BeaconBlockBellatrixToV2Blinded(bellatrixBlock.Bellatrix)
+		if err != nil {
+			return nil, status.Errorf(codes.Internal, "Could not prepare beacon block: %v", err)
+		}
+		return &ethpbv2.ProduceBlindedBlockResponse{
+			Version: ethpbv2.Version_BELLATRIX,
+			Data: &ethpbv2.BlindedBeaconBlockContainer{
+				Block: &ethpbv2.BlindedBeaconBlockContainer_BellatrixBlock{BellatrixBlock: block},
+			},
+		}, nil
+	}
+	return nil, status.Error(codes.InvalidArgument, "Unsupported block type")
+}
+
 // PrepareBeaconProposer caches and updates the fee recipient for the given proposer.
 func (vs *Server) PrepareBeaconProposer(
 	ctx context.Context, request *ethpbv1.PrepareBeaconProposerRequest,

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

@@ -1150,6 +1150,407 @@ func TestProduceBlockV2_SyncNotReady(t *testing.T) {
 	assert.ErrorContains(t, "Syncing to latest head, not ready to respond", err)
 }
 
+func TestProduceBlindedBlock(t *testing.T) {
+	t.Run("Phase 0", func(t *testing.T) {
+		db := dbutil.SetupDB(t)
+		ctx := context.Background()
+
+		beaconState, privKeys := util.DeterministicGenesisState(t, 64)
+
+		stateRoot, err := beaconState.HashTreeRoot(ctx)
+		require.NoError(t, err, "Could not hash genesis state")
+
+		genesis := blocks.NewGenesisBlock(stateRoot[:])
+		wrapped, err := wrapper.WrappedSignedBeaconBlock(genesis)
+		require.NoError(t, err)
+		require.NoError(t, db.SaveBlock(ctx, wrapped), "Could not save genesis block")
+
+		parentRoot, err := genesis.Block.HashTreeRoot()
+		require.NoError(t, err, "Could not get signing root")
+		require.NoError(t, db.SaveState(ctx, beaconState, parentRoot), "Could not save genesis state")
+		require.NoError(t, db.SaveHeadBlockRoot(ctx, parentRoot), "Could not save genesis state")
+
+		v1Alpha1Server := &v1alpha1validator.Server{
+			HeadFetcher:       &mockChain.ChainService{State: beaconState, Root: parentRoot[:]},
+			SyncChecker:       &mockSync.Sync{IsSyncing: false},
+			BlockReceiver:     &mockChain.ChainService{},
+			ChainStartFetcher: &mockPOW.POWChain{},
+			Eth1InfoFetcher:   &mockPOW.POWChain{},
+			Eth1BlockFetcher:  &mockPOW.POWChain{},
+			MockEth1Votes:     true,
+			AttPool:           attestations.NewPool(),
+			SlashingsPool:     slashings.NewPool(),
+			ExitPool:          voluntaryexits.NewPool(),
+			StateGen:          stategen.New(db),
+		}
+
+		proposerSlashings := make([]*ethpbalpha.ProposerSlashing, params.BeaconConfig().MaxProposerSlashings)
+		for i := types.ValidatorIndex(0); uint64(i) < params.BeaconConfig().MaxProposerSlashings; i++ {
+			proposerSlashing, err := util.GenerateProposerSlashingForValidator(
+				beaconState,
+				privKeys[i],
+				i, /* validator index */
+			)
+			require.NoError(t, err)
+			proposerSlashings[i] = proposerSlashing
+			err = v1Alpha1Server.SlashingsPool.InsertProposerSlashing(context.Background(), beaconState, proposerSlashing)
+			require.NoError(t, err)
+		}
+
+		attSlashings := make([]*ethpbalpha.AttesterSlashing, params.BeaconConfig().MaxAttesterSlashings)
+		for i := uint64(0); i < params.BeaconConfig().MaxAttesterSlashings; i++ {
+			attesterSlashing, err := util.GenerateAttesterSlashingForValidator(
+				beaconState,
+				privKeys[i+params.BeaconConfig().MaxProposerSlashings],
+				types.ValidatorIndex(i+params.BeaconConfig().MaxProposerSlashings), /* validator index */
+			)
+			require.NoError(t, err)
+			attSlashings[i] = attesterSlashing
+			err = v1Alpha1Server.SlashingsPool.InsertAttesterSlashing(context.Background(), beaconState, attesterSlashing)
+			require.NoError(t, err)
+		}
+
+		v1Server := &Server{
+			SyncChecker:    &mockSync.Sync{IsSyncing: false},
+			V1Alpha1Server: v1Alpha1Server,
+		}
+		randaoReveal, err := util.RandaoReveal(beaconState, 0, privKeys)
+		require.NoError(t, err)
+		graffiti := bytesutil.ToBytes32([]byte("eth2"))
+		req := &ethpbv1.ProduceBlockRequest{
+			Slot:         1,
+			RandaoReveal: randaoReveal,
+			Graffiti:     graffiti[:],
+		}
+		resp, err := v1Server.ProduceBlindedBlock(ctx, req)
+		require.NoError(t, err)
+		assert.Equal(t, ethpbv2.Version_PHASE0, resp.Version)
+
+		containerBlock, ok := resp.Data.Block.(*ethpbv2.BlindedBeaconBlockContainer_Phase0Block)
+		require.Equal(t, true, ok)
+		blk := containerBlock.Phase0Block
+		assert.Equal(t, req.Slot, blk.Slot, "Expected block to have slot of 1")
+		assert.DeepEqual(t, parentRoot[:], blk.ParentRoot, "Expected block to have correct parent root")
+		assert.DeepEqual(t, randaoReveal, blk.Body.RandaoReveal, "Expected block to have correct randao reveal")
+		assert.DeepEqual(t, req.Graffiti, blk.Body.Graffiti, "Expected block to have correct graffiti")
+		assert.Equal(t, params.BeaconConfig().MaxProposerSlashings, uint64(len(blk.Body.ProposerSlashings)))
+		expectedPropSlashings := make([]*ethpbv1.ProposerSlashing, len(proposerSlashings))
+		for i, slash := range proposerSlashings {
+			expectedPropSlashings[i] = migration.V1Alpha1ProposerSlashingToV1(slash)
+		}
+		assert.DeepEqual(t, expectedPropSlashings, blk.Body.ProposerSlashings)
+		assert.Equal(t, params.BeaconConfig().MaxAttesterSlashings, uint64(len(blk.Body.AttesterSlashings)))
+		expectedAttSlashings := make([]*ethpbv1.AttesterSlashing, len(attSlashings))
+		for i, slash := range attSlashings {
+			expectedAttSlashings[i] = migration.V1Alpha1AttSlashingToV1(slash)
+		}
+		assert.DeepEqual(t, expectedAttSlashings, blk.Body.AttesterSlashings)
+	})
+
+	t.Run("Altair", func(t *testing.T) {
+		db := dbutil.SetupDB(t)
+		ctx := context.Background()
+
+		params.SetupTestConfigCleanup(t)
+		bc := params.BeaconConfig()
+		bc.AltairForkEpoch = types.Epoch(0)
+		params.OverrideBeaconConfig(bc)
+
+		beaconState, privKeys := util.DeterministicGenesisStateAltair(t, params.BeaconConfig().SyncCommitteeSize)
+		syncCommittee, err := altair.NextSyncCommittee(context.Background(), beaconState)
+		require.NoError(t, err)
+		require.NoError(t, beaconState.SetCurrentSyncCommittee(syncCommittee))
+		require.NoError(t, beaconState.SetNextSyncCommittee(syncCommittee))
+
+		stateRoot, err := beaconState.HashTreeRoot(ctx)
+		require.NoError(t, err, "Could not hash genesis state")
+		genesisBlock := util.NewBeaconBlockAltair()
+		genesisBlock.Block.StateRoot = stateRoot[:]
+		wrappedAltairBlock, err := wrapper.WrappedSignedBeaconBlock(genesisBlock)
+		require.NoError(t, err)
+		require.NoError(t, err)
+		require.NoError(t, db.SaveBlock(ctx, wrappedAltairBlock))
+		parentRoot, err := genesisBlock.Block.HashTreeRoot()
+		require.NoError(t, err)
+
+		require.NoError(t, db.SaveState(ctx, beaconState, parentRoot), "Could not save genesis state")
+		require.NoError(t, db.SaveHeadBlockRoot(ctx, parentRoot), "Could not save genesis state")
+
+		v1Alpha1Server := &v1alpha1validator.Server{
+			HeadFetcher:       &mockChain.ChainService{State: beaconState, Root: parentRoot[:]},
+			SyncChecker:       &mockSync.Sync{IsSyncing: false},
+			BlockReceiver:     &mockChain.ChainService{},
+			ChainStartFetcher: &mockPOW.POWChain{},
+			Eth1InfoFetcher:   &mockPOW.POWChain{},
+			Eth1BlockFetcher:  &mockPOW.POWChain{},
+			MockEth1Votes:     true,
+			AttPool:           attestations.NewPool(),
+			SlashingsPool:     slashings.NewPool(),
+			ExitPool:          voluntaryexits.NewPool(),
+			StateGen:          stategen.New(db),
+			SyncCommitteePool: synccommittee.NewStore(),
+		}
+
+		proposerSlashings := make([]*ethpbalpha.ProposerSlashing, params.BeaconConfig().MaxProposerSlashings)
+		for i := types.ValidatorIndex(0); uint64(i) < params.BeaconConfig().MaxProposerSlashings; i++ {
+			proposerSlashing, err := util.GenerateProposerSlashingForValidator(
+				beaconState,
+				privKeys[i],
+				i, /* validator index */
+			)
+			require.NoError(t, err)
+			proposerSlashings[i] = proposerSlashing
+			err = v1Alpha1Server.SlashingsPool.InsertProposerSlashing(context.Background(), beaconState, proposerSlashing)
+			require.NoError(t, err)
+		}
+
+		attSlashings := make([]*ethpbalpha.AttesterSlashing, params.BeaconConfig().MaxAttesterSlashings)
+		for i := uint64(0); i < params.BeaconConfig().MaxAttesterSlashings; i++ {
+			attesterSlashing, err := util.GenerateAttesterSlashingForValidator(
+				beaconState,
+				privKeys[i+params.BeaconConfig().MaxProposerSlashings],
+				types.ValidatorIndex(i+params.BeaconConfig().MaxProposerSlashings), /* validator index */
+			)
+			require.NoError(t, err)
+			attSlashings[i] = attesterSlashing
+			err = v1Alpha1Server.SlashingsPool.InsertAttesterSlashing(context.Background(), beaconState, attesterSlashing)
+			require.NoError(t, err)
+		}
+
+		aggregationBits := bitfield.NewBitvector128()
+		for i := range aggregationBits {
+			aggregationBits[i] = 0xAA
+		}
+
+		syncCommitteeIndices, err := altair.NextSyncCommitteeIndices(context.Background(), beaconState)
+		require.NoError(t, err)
+		sigs := make([]bls.Signature, 0, len(syncCommitteeIndices))
+		for i, indice := range syncCommitteeIndices {
+			if aggregationBits.BitAt(uint64(i)) {
+				b := p2pType.SSZBytes(parentRoot[:])
+				sb, err := signing.ComputeDomainAndSign(beaconState, coreTime.CurrentEpoch(beaconState), &b, params.BeaconConfig().DomainSyncCommittee, privKeys[indice])
+				require.NoError(t, err)
+				sig, err := bls.SignatureFromBytes(sb)
+				require.NoError(t, err)
+				sigs = append(sigs, sig)
+			}
+		}
+		aggregatedSig := bls.AggregateSignatures(sigs).Marshal()
+		contribution := &ethpbalpha.SyncCommitteeContribution{
+			Slot:              0,
+			BlockRoot:         parentRoot[:],
+			SubcommitteeIndex: 0,
+			AggregationBits:   aggregationBits,
+			Signature:         aggregatedSig,
+		}
+		require.NoError(t, v1Alpha1Server.SyncCommitteePool.SaveSyncCommitteeContribution(contribution))
+
+		v1Server := &Server{
+			SyncChecker:    &mockSync.Sync{IsSyncing: false},
+			V1Alpha1Server: v1Alpha1Server,
+		}
+		randaoReveal, err := util.RandaoReveal(beaconState, 0, privKeys)
+		require.NoError(t, err)
+		graffiti := bytesutil.ToBytes32([]byte("eth2"))
+
+		req := &ethpbv1.ProduceBlockRequest{
+			Slot:         1,
+			RandaoReveal: randaoReveal,
+			Graffiti:     graffiti[:],
+		}
+		resp, err := v1Server.ProduceBlindedBlock(ctx, req)
+		require.NoError(t, err)
+		assert.Equal(t, ethpbv2.Version_ALTAIR, resp.Version)
+
+		containerBlock, ok := resp.Data.Block.(*ethpbv2.BlindedBeaconBlockContainer_AltairBlock)
+		require.Equal(t, true, ok)
+		blk := containerBlock.AltairBlock
+		assert.Equal(t, req.Slot, blk.Slot, "Expected block to have slot of 1")
+		assert.DeepEqual(t, parentRoot[:], blk.ParentRoot, "Expected block to have correct parent root")
+		assert.DeepEqual(t, randaoReveal, blk.Body.RandaoReveal, "Expected block to have correct randao reveal")
+		assert.DeepEqual(t, req.Graffiti, blk.Body.Graffiti, "Expected block to have correct graffiti")
+		assert.Equal(t, params.BeaconConfig().MaxProposerSlashings, uint64(len(blk.Body.ProposerSlashings)))
+		expectedPropSlashings := make([]*ethpbv1.ProposerSlashing, len(proposerSlashings))
+		for i, slash := range proposerSlashings {
+			expectedPropSlashings[i] = migration.V1Alpha1ProposerSlashingToV1(slash)
+		}
+		assert.DeepEqual(t, expectedPropSlashings, blk.Body.ProposerSlashings)
+		assert.Equal(t, params.BeaconConfig().MaxAttesterSlashings, uint64(len(blk.Body.AttesterSlashings)))
+		expectedAttSlashings := make([]*ethpbv1.AttesterSlashing, len(attSlashings))
+		for i, slash := range attSlashings {
+			expectedAttSlashings[i] = migration.V1Alpha1AttSlashingToV1(slash)
+		}
+		assert.DeepEqual(t, expectedAttSlashings, blk.Body.AttesterSlashings)
+		expectedBits := bitfield.NewBitvector512()
+		for i := 0; i <= 15; i++ {
+			expectedBits[i] = 0xAA
+		}
+		assert.DeepEqual(t, expectedBits, blk.Body.SyncAggregate.SyncCommitteeBits)
+		assert.DeepEqual(t, aggregatedSig, blk.Body.SyncAggregate.SyncCommitteeSignature)
+	})
+
+	t.Run("Bellatrix", func(t *testing.T) {
+		db := dbutil.SetupDB(t)
+		ctx := context.Background()
+
+		params.SetupTestConfigCleanup(t)
+		bc := params.BeaconConfig()
+		bc.AltairForkEpoch = types.Epoch(0)
+		bc.BellatrixForkEpoch = types.Epoch(1)
+		params.OverrideBeaconConfig(bc)
+
+		beaconState, privKeys := util.DeterministicGenesisStateBellatrix(t, params.BeaconConfig().SyncCommitteeSize)
+		require.NoError(t, beaconState.SetSlot(params.BeaconConfig().SlotsPerEpoch))
+		syncCommittee, err := altair.NextSyncCommittee(context.Background(), beaconState)
+		require.NoError(t, err)
+		require.NoError(t, beaconState.SetCurrentSyncCommittee(syncCommittee))
+		require.NoError(t, beaconState.SetNextSyncCommittee(syncCommittee))
+
+		stateRoot, err := beaconState.HashTreeRoot(ctx)
+		require.NoError(t, err, "Could not hash genesis state")
+		genesisBlock := util.NewBeaconBlockBellatrix()
+		genesisBlock.Block.StateRoot = stateRoot[:]
+		wrappedBellatrixBlock, err := wrapper.WrappedSignedBeaconBlock(genesisBlock)
+		require.NoError(t, err)
+		require.NoError(t, db.SaveBlock(ctx, wrappedBellatrixBlock))
+		parentRoot, err := genesisBlock.Block.HashTreeRoot()
+		require.NoError(t, err)
+
+		require.NoError(t, db.SaveState(ctx, beaconState, parentRoot), "Could not save genesis state")
+		require.NoError(t, db.SaveHeadBlockRoot(ctx, parentRoot), "Could not save genesis state")
+
+		v1Alpha1Server := &v1alpha1validator.Server{
+			ExecutionEngineCaller: &mockPOW.EngineClient{
+				ExecutionBlock: &enginev1.ExecutionBlock{
+					TotalDifficulty: "0x1",
+				},
+			},
+			TimeFetcher:            &mockChain.ChainService{},
+			HeadFetcher:            &mockChain.ChainService{State: beaconState, Root: parentRoot[:]},
+			SyncChecker:            &mockSync.Sync{IsSyncing: false},
+			BlockReceiver:          &mockChain.ChainService{},
+			ChainStartFetcher:      &mockPOW.POWChain{},
+			Eth1InfoFetcher:        &mockPOW.POWChain{},
+			Eth1BlockFetcher:       &mockPOW.POWChain{},
+			MockEth1Votes:          true,
+			AttPool:                attestations.NewPool(),
+			SlashingsPool:          slashings.NewPool(),
+			ExitPool:               voluntaryexits.NewPool(),
+			StateGen:               stategen.New(db),
+			SyncCommitteePool:      synccommittee.NewStore(),
+			ProposerSlotIndexCache: cache.NewProposerPayloadIDsCache(),
+		}
+
+		proposerSlashings := make([]*ethpbalpha.ProposerSlashing, params.BeaconConfig().MaxProposerSlashings)
+		for i := types.ValidatorIndex(0); uint64(i) < params.BeaconConfig().MaxProposerSlashings; i++ {
+			proposerSlashing, err := util.GenerateProposerSlashingForValidator(
+				beaconState,
+				privKeys[i],
+				i,
+			)
+			require.NoError(t, err)
+			proposerSlashings[i] = proposerSlashing
+			err = v1Alpha1Server.SlashingsPool.InsertProposerSlashing(context.Background(), beaconState, proposerSlashing)
+			require.NoError(t, err)
+		}
+
+		attSlashings := make([]*ethpbalpha.AttesterSlashing, params.BeaconConfig().MaxAttesterSlashings)
+		for i := uint64(0); i < params.BeaconConfig().MaxAttesterSlashings; i++ {
+			attesterSlashing, err := util.GenerateAttesterSlashingForValidator(
+				beaconState,
+				privKeys[i+params.BeaconConfig().MaxProposerSlashings],
+				types.ValidatorIndex(i+params.BeaconConfig().MaxProposerSlashings), /* validator index */
+			)
+			require.NoError(t, err)
+			attSlashings[i] = attesterSlashing
+			err = v1Alpha1Server.SlashingsPool.InsertAttesterSlashing(context.Background(), beaconState, attesterSlashing)
+			require.NoError(t, err)
+		}
+
+		aggregationBits := bitfield.NewBitvector128()
+		for i := range aggregationBits {
+			aggregationBits[i] = 0xAA
+		}
+
+		syncCommitteeIndices, err := altair.NextSyncCommitteeIndices(context.Background(), beaconState)
+		require.NoError(t, err)
+		sigs := make([]bls.Signature, 0, len(syncCommitteeIndices))
+		for i, indice := range syncCommitteeIndices {
+			if aggregationBits.BitAt(uint64(i)) {
+				b := p2pType.SSZBytes(parentRoot[:])
+				sb, err := signing.ComputeDomainAndSign(beaconState, coreTime.CurrentEpoch(beaconState), &b, params.BeaconConfig().DomainSyncCommittee, privKeys[indice])
+				require.NoError(t, err)
+				sig, err := bls.SignatureFromBytes(sb)
+				require.NoError(t, err)
+				sigs = append(sigs, sig)
+			}
+		}
+		aggregatedSig := bls.AggregateSignatures(sigs).Marshal()
+		contribution := &ethpbalpha.SyncCommitteeContribution{
+			Slot:              params.BeaconConfig().SlotsPerEpoch,
+			BlockRoot:         parentRoot[:],
+			SubcommitteeIndex: 0,
+			AggregationBits:   aggregationBits,
+			Signature:         aggregatedSig,
+		}
+		require.NoError(t, v1Alpha1Server.SyncCommitteePool.SaveSyncCommitteeContribution(contribution))
+
+		v1Server := &Server{
+			V1Alpha1Server: v1Alpha1Server,
+			SyncChecker:    &mockSync.Sync{IsSyncing: false},
+		}
+		randaoReveal, err := util.RandaoReveal(beaconState, 1, privKeys)
+		require.NoError(t, err)
+		graffiti := bytesutil.ToBytes32([]byte("eth2"))
+
+		req := &ethpbv1.ProduceBlockRequest{
+			Slot:         params.BeaconConfig().SlotsPerEpoch + 1,
+			RandaoReveal: randaoReveal,
+			Graffiti:     graffiti[:],
+		}
+		resp, err := v1Server.ProduceBlindedBlock(ctx, req)
+		require.NoError(t, err)
+		assert.Equal(t, ethpbv2.Version_BELLATRIX, resp.Version)
+
+		containerBlock, ok := resp.Data.Block.(*ethpbv2.BlindedBeaconBlockContainer_BellatrixBlock)
+		require.Equal(t, true, ok)
+		blk := containerBlock.BellatrixBlock
+		assert.Equal(t, req.Slot, blk.Slot, "Expected block to have slot of 1")
+		assert.DeepEqual(t, parentRoot[:], blk.ParentRoot, "Expected block to have correct parent root")
+		assert.DeepEqual(t, randaoReveal, blk.Body.RandaoReveal, "Expected block to have correct randao reveal")
+		assert.DeepEqual(t, req.Graffiti, blk.Body.Graffiti, "Expected block to have correct graffiti")
+		assert.Equal(t, params.BeaconConfig().MaxProposerSlashings, uint64(len(blk.Body.ProposerSlashings)))
+		expectedPropSlashings := make([]*ethpbv1.ProposerSlashing, len(proposerSlashings))
+		for i, slash := range proposerSlashings {
+			expectedPropSlashings[i] = migration.V1Alpha1ProposerSlashingToV1(slash)
+		}
+		assert.DeepEqual(t, expectedPropSlashings, blk.Body.ProposerSlashings)
+		assert.Equal(t, params.BeaconConfig().MaxAttesterSlashings, uint64(len(blk.Body.AttesterSlashings)))
+		expectedAttSlashings := make([]*ethpbv1.AttesterSlashing, len(attSlashings))
+		for i, slash := range attSlashings {
+			expectedAttSlashings[i] = migration.V1Alpha1AttSlashingToV1(slash)
+		}
+		assert.DeepEqual(t, expectedAttSlashings, blk.Body.AttesterSlashings)
+		expectedBits := bitfield.NewBitvector512()
+		for i := 0; i <= 15; i++ {
+			expectedBits[i] = 0xAA
+		}
+		assert.DeepEqual(t, expectedBits, blk.Body.SyncAggregate.SyncCommitteeBits)
+		assert.DeepEqual(t, aggregatedSig, blk.Body.SyncAggregate.SyncCommitteeSignature)
+	})
+}
+
+func TestProduceBlindedBlock_SyncNotReady(t *testing.T) {
+	chainService := &mockChain.ChainService{}
+	vs := &Server{
+		SyncChecker: &mockSync.Sync{IsSyncing: true},
+		HeadFetcher: chainService,
+		TimeFetcher: chainService,
+	}
+	_, err := vs.ProduceBlindedBlock(context.Background(), &ethpbv1.ProduceBlockRequest{})
+	assert.ErrorContains(t, "Syncing to latest head, not ready to respond", err)
+}
+
 func TestProduceAttestationData(t *testing.T) {
 	block := util.NewBeaconBlock()
 	block.Block.Slot = 3*params.BeaconConfig().SlotsPerEpoch + 1

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

@@ -9,7 +9,7 @@ import (
 
 // GetForkChoice returns a fork choice store.
 func (ds *Server) GetForkChoice(_ context.Context, _ *empty.Empty) (*pbrpc.ForkChoiceResponse, error) {
-	store := ds.HeadFetcher.ForkChoicer()
+	store := ds.ForkFetcher.ForkChoicer()
 
 	return &pbrpc.ForkChoiceResponse{
 		JustifiedEpoch:  store.JustifiedEpoch(),

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

@@ -13,7 +13,7 @@ import (
 
 func TestServer_GetForkChoice_ProtoArray(t *testing.T) {
 	store := protoarray.New(0, 0, [32]byte{'a'})
-	bs := &Server{HeadFetcher: &mock.ChainService{ForkChoiceStore: store}}
+	bs := &Server{ForkFetcher: &mock.ChainService{ForkChoiceStore: store}}
 	res, err := bs.GetForkChoice(context.Background(), &empty.Empty{})
 	require.NoError(t, err)
 	assert.Equal(t, store.JustifiedEpoch(), res.JustifiedEpoch, "Did not get wanted justified epoch")

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

@@ -28,6 +28,7 @@ type Server struct {
 	GenesisTimeFetcher blockchain.TimeFetcher
 	StateGen           *stategen.State
 	HeadFetcher        blockchain.HeadFetcher
+	ForkFetcher        blockchain.ForkFetcher
 	PeerManager        p2p.PeerManager
 	PeersFetcher       p2p.PeersProvider
 	ReplayerBuilder    stategen.ReplayerBuilder

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

@@ -52,7 +52,6 @@ go_library(
         "//beacon-chain/state:go_default_library",
         "//beacon-chain/state/stategen:go_default_library",
         "//beacon-chain/sync:go_default_library",
-        "//config/features:go_default_library",
         "//config/fieldparams:go_default_library",
         "//config/params:go_default_library",
         "//container/trie:go_default_library",
@@ -77,7 +76,6 @@ go_library(
         "@com_github_ethereum_go_ethereum//common:go_default_library",
         "@com_github_ethereum_go_ethereum//common/hexutil:go_default_library",
         "@com_github_ferranbt_fastssz//:go_default_library",
-        "@com_github_holiman_uint256//:go_default_library",
         "@com_github_pkg_errors//:go_default_library",
         "@com_github_prometheus_client_golang//prometheus:go_default_library",
         "@com_github_prometheus_client_golang//prometheus/promauto:go_default_library",
@@ -141,7 +139,6 @@ go_test(
         "//beacon-chain/state/stategen/mock:go_default_library",
         "//beacon-chain/state/v1:go_default_library",
         "//beacon-chain/sync/initial-sync/testing:go_default_library",
-        "//config/features:go_default_library",
         "//config/fieldparams:go_default_library",
         "//config/params:go_default_library",
         "//container/trie:go_default_library",
@@ -162,7 +159,6 @@ go_test(
         "@com_github_d4l3k_messagediff//:go_default_library",
         "@com_github_ethereum_go_ethereum//common:go_default_library",
         "@com_github_golang_mock//gomock:go_default_library",
-        "@com_github_holiman_uint256//:go_default_library",
         "@com_github_prysmaticlabs_eth2_types//:go_default_library",
         "@com_github_prysmaticlabs_go_bitfield//:go_default_library",
         "@com_github_sirupsen_logrus//:go_default_library",

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

@@ -37,17 +37,24 @@ func (vs *Server) StreamBlocksAltair(req *ethpb.StreamBlocksRequest, stream ethp
 					case version.Phase0:
 						phBlk, ok := data.SignedBlock.Proto().(*ethpb.SignedBeaconBlock)
 						if !ok {
-							log.Warn("Mismatch between version and block type, was expecting *ethpb.SignedBeaconBlock")
+							log.Warn("Mismatch between version and block type, was expecting SignedBeaconBlock")
 							continue
 						}
 						b.Block = &ethpb.StreamBlocksResponse_Phase0Block{Phase0Block: phBlk}
 					case version.Altair:
 						phBlk, ok := data.SignedBlock.Proto().(*ethpb.SignedBeaconBlockAltair)
 						if !ok {
-							log.Warn("Mismatch between version and block type, was expecting *v2.SignedBeaconBlockAltair")
+							log.Warn("Mismatch between version and block type, was expecting SignedBeaconBlockAltair")
 							continue
 						}
 						b.Block = &ethpb.StreamBlocksResponse_AltairBlock{AltairBlock: phBlk}
+					case version.Bellatrix:
+						phBlk, ok := data.SignedBlock.Proto().(*ethpb.SignedBeaconBlockBellatrix)
+						if !ok {
+							log.Warn("Mismatch between version and block type, was expecting SignedBeaconBlockBellatrix")
+							continue
+						}
+						b.Block = &ethpb.StreamBlocksResponse_BellatrixBlock{BellatrixBlock: phBlk}
 					}
 
 					if err := stream.Send(b); err != nil {

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

@@ -11,7 +11,6 @@ import (
 	"github.com/prysmaticlabs/prysm/beacon-chain/core/blocks"
 	"github.com/prysmaticlabs/prysm/beacon-chain/core/helpers"
 	"github.com/prysmaticlabs/prysm/beacon-chain/state"
-	"github.com/prysmaticlabs/prysm/config/features"
 	"github.com/prysmaticlabs/prysm/config/params"
 	ethpb "github.com/prysmaticlabs/prysm/proto/prysm/v1alpha1"
 	"github.com/prysmaticlabs/prysm/proto/prysm/v1alpha1/attestation/aggregation"
@@ -117,16 +116,7 @@ func (a proposerAtts) sortByProfitability() (proposerAtts, error) {
 	if len(a) < 2 {
 		return a, nil
 	}
-	if features.Get().ProposerAttsSelectionUsingMaxCover {
-		return a.sortByProfitabilityUsingMaxCover()
-	}
-	sort.Slice(a, func(i, j int) bool {
-		if a[i].Data.Slot == a[j].Data.Slot {
-			return a[i].AggregationBits.Count() > a[j].AggregationBits.Count()
-		}
-		return a[i].Data.Slot > a[j].Data.Slot
-	})
-	return a, nil
+	return a.sortByProfitabilityUsingMaxCover()
 }
 
 // sortByProfitabilityUsingMaxCover orders attestations by highest slot and by highest aggregation bit count.

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

@@ -7,7 +7,6 @@ import (
 
 	types "github.com/prysmaticlabs/eth2-types"
 	"github.com/prysmaticlabs/go-bitfield"
-	"github.com/prysmaticlabs/prysm/config/features"
 	ethpb "github.com/prysmaticlabs/prysm/proto/prysm/v1alpha1"
 	"github.com/prysmaticlabs/prysm/testing/assert"
 	"github.com/prysmaticlabs/prysm/testing/require"
@@ -39,11 +38,6 @@ func TestProposer_ProposerAtts_sortByProfitability(t *testing.T) {
 }
 
 func TestProposer_ProposerAtts_sortByProfitabilityUsingMaxCover(t *testing.T) {
-	resetCfg := features.InitWithReset(&features.Flags{
-		ProposerAttsSelectionUsingMaxCover: true,
-	})
-	defer resetCfg()
-
 	type testData struct {
 		slot types.Slot
 		bits bitfield.Bitlist
@@ -116,38 +110,9 @@ func TestProposer_ProposerAtts_sortByProfitabilityUsingMaxCover(t *testing.T) {
 	})
 
 	t.Run("compare to native sort", func(t *testing.T) {
-		// The naive sort will end up with 0b11001000 being selected second (which is not optimal
-		// as it only contains a single unknown bit).
 		// The max-cover based approach will select 0b00001100 instead, despite lower bit count
 		// (since it has two new/unknown bits).
-		t.Run("naive", func(t *testing.T) {
-			resetCfg := features.InitWithReset(&features.Flags{
-				ProposerAttsSelectionUsingMaxCover: false,
-			})
-			defer resetCfg()
-
-			atts := getAtts([]testData{
-				{1, bitfield.Bitlist{0b11000011, 0b1}},
-				{1, bitfield.Bitlist{0b11001000, 0b1}},
-				{1, bitfield.Bitlist{0b00001100, 0b1}},
-			})
-			want := getAtts([]testData{
-				{1, bitfield.Bitlist{0b11000011, 0b1}},
-				{1, bitfield.Bitlist{0b11001000, 0b1}},
-				{1, bitfield.Bitlist{0b00001100, 0b1}},
-			})
-			atts, err := atts.sortByProfitability()
-			if err != nil {
-				t.Error(err)
-			}
-			require.DeepEqual(t, want, atts)
-		})
 		t.Run("max-cover", func(t *testing.T) {
-			resetCfg := features.InitWithReset(&features.Flags{
-				ProposerAttsSelectionUsingMaxCover: true,
-			})
-			defer resetCfg()
-
 			atts := getAtts([]testData{
 				{1, bitfield.Bitlist{0b11000011, 0b1}},
 				{1, bitfield.Bitlist{0b11001000, 0b1}},