Add staticcheck to github actions

* Set boost with deterministic timing

* confs

* gaz

* Update runner.go

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

.bazelrc

@@ -217,3 +217,6 @@ build:remote --remote_local_fallback
 
 # Ignore GoStdLib with remote caching
 build --modify_execution_info='GoStdlib.*=+no-remote-cache'
+
+# Set bazel gotag
+build --define gotags=bazel

.bazelversion

@@ -1 +1 @@
-4.2.2
+5.0.0

.buildkite-bazelrc

@@ -10,31 +10,31 @@
 
 # Prysm specific remote-cache properties.
 #build:remote-cache --disk_cache=
-build:remote-cache --remote_download_toplevel
+build:remote-cache --remote_download_minimal
 build:remote-cache --remote_cache=grpc://bazel-remote-cache:9092
 build:remote-cache --experimental_remote_downloader=grpc://bazel-remote-cache:9092
 build:remote-cache --remote_local_fallback
+build:remote-cache --experimental_remote_cache_async
+build:remote-cache --experimental_remote_merkle_tree_cache
+build:remote-cache --experimental_action_cache_store_output_metadata
+build:remote-cache --experimental_remote_cache_compression
 # Enforce stricter environment rules, which eliminates some non-hermetic
 # behavior and therefore improves both the remote cache hit rate and the
 # correctness and repeatability of the build.
 build:remote-cache --incompatible_strict_action_env=true
 
+build --experimental_use_hermetic_linux_sandbox
+
 # Import workspace options.
 import %workspace%/.bazelrc
 
-startup --host_jvm_args=-Xmx2g --host_jvm_args=-Xms2g
-query --repository_cache=/tmp/repositorycache
-query --experimental_repository_cache_hardlinks
-build --repository_cache=/tmp/repositorycache
-build --experimental_repository_cache_hardlinks
+startup --host_jvm_args=-Xmx4g --host_jvm_args=-Xms2g
 build --experimental_strict_action_env
-build --disk_cache=/tmp/bazelbuilds
-build --experimental_multi_threaded_digest
 build --sandbox_tmpfs_path=/tmp
 build --verbose_failures
 build --announce_rc
 build --show_progress_rate_limit=5
-build --curses=yes --color=no
+build --curses=no --color=no
 build --keep_going
 build --test_output=errors
 build --flaky_test_attempts=5

.github/actions/gomodtidy/entrypoint.sh

@@ -7,7 +7,7 @@ cd $GITHUB_WORKSPACE
 cp go.mod go.mod.orig
 cp go.sum go.sum.orig
 
-go mod tidy
+go mod tidy -compat=1.17
 
 echo "Checking go.mod and go.sum:"
 checks=0

.github/workflows/go.yml

@@ -40,6 +40,11 @@ jobs:
         uses: golangci/golangci-lint-action@v2
         with:
           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
+      
+      - name: staticcheck
+        uses: dominikh/staticcheck-action@v1.1.0
+        with:
+          version: "2021.1.1"
 
   build:
     name: Build

BUILD.bazel

@@ -3,7 +3,7 @@ load("@com_github_atlassian_bazel_tools//gometalinter:def.bzl", "gometalinter")
 load("@com_github_atlassian_bazel_tools//goimports:def.bzl", "goimports")
 load("@io_kubernetes_build//defs:run_in_workspace.bzl", "workspace_binary")
 load("@io_bazel_rules_go//go:def.bzl", "nogo")
-load("@graknlabs_bazel_distribution//common:rules.bzl", "assemble_targz", "assemble_versioned")
+load("@vaticle_bazel_distribution//common:rules.bzl", "assemble_targz", "assemble_versioned")
 load("@bazel_skylib//rules:common_settings.bzl", "string_setting")
 
 prefix = "github.com/prysmaticlabs/prysm"
@@ -16,6 +16,8 @@ exports_files([
 # gazelle:map_kind go_library go_library @prysm//tools/go:def.bzl
 # gazelle:map_kind go_test go_test @prysm//tools/go:def.bzl
 # gazelle:map_kind go_repository go_repository @prysm//tools/go:def.bzl
+# gazelle:build_tags bazel
+# gazelle:exclude tools/analyzers/**/testdata/**
 gazelle(
     name = "gazelle",
     prefix = prefix,
@@ -125,6 +127,7 @@ nogo(
         "//tools/analyzers/ineffassign:go_default_library",
         "//tools/analyzers/properpermissions:go_default_library",
         "//tools/analyzers/recursivelock:go_default_library",
+        "//tools/analyzers/uintcast:go_default_library",
     ] + select({
         # nogo checks that fail with coverage enabled.
         ":coverage_enabled": [],

WORKSPACE

@@ -117,13 +117,6 @@ http_archive(
     urls = ["https://github.com/fuzzitdev/fuzzit/releases/download/v2.4.76/fuzzit_Linux_x86_64.zip"],
 )
 
-git_repository(
-    name = "graknlabs_bazel_distribution",
-    commit = "962f3a7e56942430c0ec120c24f9e9f2a9c2ce1a",
-    remote = "https://github.com/graknlabs/bazel-distribution",
-    shallow_since = "1569509514 +0300",
-)
-
 load(
     "@io_bazel_rules_docker//repositories:repositories.bzl",
     container_repositories = "repositories",
@@ -222,7 +215,7 @@ filegroup(
     url = "https://github.com/eth-clients/slashing-protection-interchange-tests/archive/b8413ca42dc92308019d0d4db52c87e9e125c4e9.tar.gz",
 )
 
-consensus_spec_version = "v1.1.9"
+consensus_spec_version = "v1.1.10"
 
 bls_test_version = "v0.1.1"
 
@@ -238,7 +231,7 @@ filegroup(
     visibility = ["//visibility:public"],
 )
     """,
-    sha256 = "207d9c326ba4fa1f34bab7b6169201c32f2611755db030909a3405873445e0ba",
+    sha256 = "28043009cc2f6fc9804e73c8c1fc2cb27062f1591e6884f3015ae1dd7a276883",
     url = "https://github.com/ethereum/consensus-spec-tests/releases/download/%s/general.tar.gz" % consensus_spec_version,
 )
 
@@ -254,7 +247,7 @@ filegroup(
     visibility = ["//visibility:public"],
 )
     """,
-    sha256 = "a3995b39f412db236b2f1db909f288218da53cb53b9923b71dda9d144d68f40a",
+    sha256 = "bc1a283ca068f310f04d70c4f6a8eaa0b8f7e9318073a8bdc2ee233111b4e339",
     url = "https://github.com/ethereum/consensus-spec-tests/releases/download/%s/minimal.tar.gz" % consensus_spec_version,
 )
 
@@ -270,7 +263,7 @@ filegroup(
     visibility = ["//visibility:public"],
 )
     """,
-    sha256 = "76cea7a4c8e32d458ad456b54bfbb30bc772481a91954a4cd97e229aa3023b1d",
+    sha256 = "bbabb482c229ff9d4e2c7b77c992edb452f9d0af7c6d8dd4f922f06a7b101e81",
     url = "https://github.com/ethereum/consensus-spec-tests/releases/download/%s/mainnet.tar.gz" % consensus_spec_version,
 )
 
@@ -285,7 +278,7 @@ filegroup(
     visibility = ["//visibility:public"],
 )
     """,
-    sha256 = "0fc429684775f943250dce1f9c485ac25e26c6395d7f585c8d1317becec2ace7",
+    sha256 = "408a5524548ad3fcf387f65ac7ec52781d9ee899499720bb12451b48a15818d4",
     strip_prefix = "consensus-specs-" + consensus_spec_version[1:],
     url = "https://github.com/ethereum/consensus-specs/archive/refs/tags/%s.tar.gz" % consensus_spec_version,
 )

api/client/beacon/BUILD.bazel

@@ -0,0 +1,54 @@
+load("@prysm//tools/go:def.bzl", "go_library", "go_test")
+
+go_library(
+    name = "go_default_library",
+    srcs = [
+        "checkpoint.go",
+        "client.go",
+        "doc.go",
+        "errors.go",
+    ],
+    importpath = "github.com/prysmaticlabs/prysm/api/client/beacon",
+    visibility = ["//visibility:public"],
+    deps = [
+        "//beacon-chain/core/helpers:go_default_library",
+        "//beacon-chain/rpc/apimiddleware:go_default_library",
+        "//beacon-chain/state:go_default_library",
+        "//encoding/bytesutil:go_default_library",
+        "//encoding/ssz/detect:go_default_library",
+        "//io/file:go_default_library",
+        "//network/forks:go_default_library",
+        "//proto/prysm/v1alpha1:go_default_library",
+        "//proto/prysm/v1alpha1/block:go_default_library",
+        "//runtime/version:go_default_library",
+        "//time/slots:go_default_library",
+        "@com_github_ethereum_go_ethereum//common/hexutil:go_default_library",
+        "@com_github_pkg_errors//:go_default_library",
+        "@com_github_prysmaticlabs_eth2_types//:go_default_library",
+        "@com_github_sirupsen_logrus//:go_default_library",
+        "@org_golang_x_mod//semver:go_default_library",
+    ],
+)
+
+go_test(
+    name = "go_default_test",
+    srcs = [
+        "checkpoint_test.go",
+        "client_test.go",
+    ],
+    embed = [":go_default_library"],
+    deps = [
+        "//beacon-chain/state:go_default_library",
+        "//config/params:go_default_library",
+        "//encoding/ssz/detect:go_default_library",
+        "//network/forks:go_default_library",
+        "//proto/prysm/v1alpha1:go_default_library",
+        "//proto/prysm/v1alpha1/wrapper:go_default_library",
+        "//runtime/version:go_default_library",
+        "//testing/require:go_default_library",
+        "//testing/util:go_default_library",
+        "//time/slots:go_default_library",
+        "@com_github_pkg_errors//:go_default_library",
+        "@com_github_prysmaticlabs_eth2_types//:go_default_library",
+    ],
+)

api/client/beacon/checkpoint.go

@@ -0,0 +1,262 @@
+package beacon
+
+import (
+	"context"
+	"fmt"
+	"path"
+
+	"github.com/pkg/errors"
+	types "github.com/prysmaticlabs/eth2-types"
+	"github.com/prysmaticlabs/prysm/beacon-chain/core/helpers"
+	"github.com/prysmaticlabs/prysm/beacon-chain/state"
+	"github.com/prysmaticlabs/prysm/encoding/ssz/detect"
+	"github.com/prysmaticlabs/prysm/io/file"
+	"github.com/prysmaticlabs/prysm/proto/prysm/v1alpha1/block"
+	"github.com/prysmaticlabs/prysm/runtime/version"
+	"github.com/prysmaticlabs/prysm/time/slots"
+	log "github.com/sirupsen/logrus"
+	"golang.org/x/mod/semver"
+)
+
+// OriginData represents the BeaconState and SignedBeaconBlock necessary to start an empty Beacon Node
+// using Checkpoint Sync.
+type OriginData struct {
+	wsd *WeakSubjectivityData
+	sb  []byte
+	bb  []byte
+	st  state.BeaconState
+	b   block.SignedBeaconBlock
+	cf  *detect.VersionedUnmarshaler
+}
+
+// CheckpointString returns the standard string representation of a Checkpoint for the block root and epoch for the
+// SignedBeaconBlock value found by DownloadOriginData.
+// The format is a a hex-encoded block root, followed by the epoch of the block, separated by a colon. For example:
+// "0x1c35540cac127315fabb6bf29181f2ae0de1a3fc909d2e76ba771e61312cc49a:74888"
+func (od *OriginData) CheckpointString() string {
+	return fmt.Sprintf("%#x:%d", od.wsd.BlockRoot, od.wsd.Epoch)
+}
+
+// SaveBlock saves the downloaded block to a unique file in the given path.
+// For readability and collision avoidance, the file name includes: type, config name, slot and root
+func (od *OriginData) SaveBlock(dir string) (string, error) {
+	blockPath := path.Join(dir, fname("state", od.cf, od.st.Slot(), od.wsd.BlockRoot))
+	return blockPath, file.WriteFile(blockPath, od.sb)
+}
+
+// SaveState saves the downloaded state to a unique file in the given path.
+// For readability and collision avoidance, the file name includes: type, config name, slot and root
+func (od *OriginData) SaveState(dir string) (string, error) {
+	statePath := path.Join(dir, fname("state", od.cf, od.st.Slot(), od.wsd.StateRoot))
+	return statePath, file.WriteFile(statePath, od.sb)
+}
+
+// StateBytes returns the ssz-encoded bytes of the downloaded BeaconState value.
+func (od *OriginData) StateBytes() []byte {
+	return od.sb
+}
+
+// BlockBytes returns the ssz-encoded bytes of the downloaded SignedBeaconBlock value.
+func (od *OriginData) BlockBytes() []byte {
+	return od.bb
+}
+
+func fname(prefix string, cf *detect.VersionedUnmarshaler, slot types.Slot, root [32]byte) string {
+	return fmt.Sprintf("%s_%s_%s_%d-%#x.ssz", prefix, cf.Config.ConfigName, version.String(cf.Fork), slot, root)
+}
+
+// this method downloads the head state, which can be used to find the correct chain config
+// and use prysm's helper methods to compute the latest weak subjectivity epoch.
+func getWeakSubjectivityEpochFromHead(ctx context.Context, client *Client) (types.Epoch, error) {
+	headBytes, err := client.GetState(ctx, IdHead)
+	if err != nil {
+		return 0, err
+	}
+	cf, err := detect.FromState(headBytes)
+	if err != nil {
+		return 0, errors.Wrap(err, "error detecting chain config for beacon state")
+	}
+	log.Printf("detected supported config in remote head state, name=%s, fork=%s", cf.Config.ConfigName, version.String(cf.Fork))
+	headState, err := cf.UnmarshalBeaconState(headBytes)
+	if err != nil {
+		return 0, errors.Wrap(err, "error unmarshaling state to correct version")
+	}
+
+	epoch, err := helpers.LatestWeakSubjectivityEpoch(ctx, headState, cf.Config)
+	if err != nil {
+		return 0, errors.Wrap(err, "error computing the weak subjectivity epoch from head state")
+	}
+
+	log.Printf("(computed client-side) weak subjectivity epoch = %d", epoch)
+	return epoch, nil
+}
+
+const (
+	prysmMinimumVersion     = "v2.0.7"
+	prysmImplementationName = "Prysm"
+)
+
+// ErrUnsupportedPrysmCheckpointVersion indicates remote beacon node can't be used for checkpoint retrieval.
+var ErrUnsupportedPrysmCheckpointVersion = errors.New("node does not meet minimum version requirements for checkpoint retrieval")
+
+// for older endpoints or clients that do not support the weak_subjectivity api method
+// we gather the necessary data for a checkpoint sync by:
+// - inspecting the remote server's head state and computing the weak subjectivity epoch locally
+// - requesting the state at the first slot of the epoch
+// - using hash_tree_root(state.latest_block_header) to compute the block the state integrates
+// - requesting that block by its root
+func downloadBackwardsCompatible(ctx context.Context, client *Client) (*OriginData, error) {
+	log.Print("falling back to generic checkpoint derivation, weak_subjectivity API not supported by server")
+	nv, err := client.GetNodeVersion(ctx)
+	if err != nil {
+		return nil, errors.Wrap(err, "unable to proceed with fallback method without confirming node version")
+	}
+	if nv.implementation == prysmImplementationName && semver.Compare(nv.semver, prysmMinimumVersion) < 0 {
+		return nil, errors.Wrapf(ErrUnsupportedPrysmCheckpointVersion, "%s < minimum (%s)", nv.semver, prysmMinimumVersion)
+	}
+	epoch, err := getWeakSubjectivityEpochFromHead(ctx, client)
+	if err != nil {
+		return nil, errors.Wrap(err, "error computing weak subjectivity epoch via head state inspection")
+	}
+
+	// use first slot of the epoch for the state slot
+	slot, err := slots.EpochStart(epoch)
+	if err != nil {
+		return nil, errors.Wrapf(err, "error computing first slot of epoch=%d", epoch)
+	}
+
+	log.Printf("requesting checkpoint state at slot %d", slot)
+	// get the state at the first slot of the epoch
+	stateBytes, err := client.GetState(ctx, IdFromSlot(slot))
+	if err != nil {
+		return nil, errors.Wrapf(err, "failed to request state by slot from api, slot=%d", slot)
+	}
+
+	// ConfigFork is used to unmarshal the BeaconState so we can read the block root in latest_block_header
+	cf, err := detect.FromState(stateBytes)
+	if err != nil {
+		return nil, errors.Wrap(err, "error detecting chain config for beacon state")
+	}
+	log.Printf("detected supported config in checkpoint state, name=%s, fork=%s", cf.Config.ConfigName, version.String(cf.Fork))
+
+	st, err := cf.UnmarshalBeaconState(stateBytes)
+	if err != nil {
+		return nil, errors.Wrap(err, "error using detected config fork to unmarshal state bytes")
+	}
+
+	// compute state and block roots
+	stateRoot, err := st.HashTreeRoot(ctx)
+	if err != nil {
+		return nil, errors.Wrap(err, "error computing hash_tree_root of state")
+	}
+
+	header := st.LatestBlockHeader()
+	header.StateRoot = stateRoot[:]
+	computedBlockRoot, err := header.HashTreeRoot()
+	if err != nil {
+		return nil, errors.Wrap(err, "error while computing block root using state data")
+	}
+
+	blockBytes, err := client.GetBlock(ctx, IdFromRoot(computedBlockRoot))
+	if err != nil {
+		return nil, errors.Wrapf(err, "error requesting block by root = %d", computedBlockRoot)
+	}
+	block, err := cf.UnmarshalBeaconBlock(blockBytes)
+	if err != nil {
+		return nil, errors.Wrap(err, "unable to unmarshal block to a supported type using the detected fork schedule")
+	}
+	blockRoot, err := block.Block().HashTreeRoot()
+	if err != nil {
+		return nil, errors.Wrap(err, "error computing hash_tree_root for block obtained via root")
+	}
+
+	log.Printf("BeaconState slot=%d, Block slot=%d", st.Slot(), block.Block().Slot())
+	log.Printf("BeaconState htr=%#xd, Block state_root=%#x", stateRoot, block.Block().StateRoot())
+	log.Printf("BeaconBlock root computed from state=%#x, Block htr=%#x", computedBlockRoot, blockRoot)
+
+	return &OriginData{
+		wsd: &WeakSubjectivityData{
+			BlockRoot: blockRoot,
+			StateRoot: stateRoot,
+			Epoch:     epoch,
+		},
+		st: st,
+		sb: stateBytes,
+		b:  block,
+		bb: blockBytes,
+		cf: cf,
+	}, nil
+}
+
+// DownloadOriginData attempts to use the proposed weak_subjectivity beacon node api
+// to obtain the weak_subjectivity metadata (epoch, block_root, state_root) needed to sync
+// a beacon node from the canonical weak subjectivity checkpoint. As this is a proposed API
+// that will only be supported by prysm at first, in the event of a 404 we fallback to using a
+// different technique where we first download the head state which can be used to compute the
+// weak subjectivity epoch on the client side.
+func DownloadOriginData(ctx context.Context, client *Client) (*OriginData, error) {
+	ws, err := client.GetWeakSubjectivity(ctx)
+	if err != nil {
+		// a 404/405 is expected if querying an endpoint that doesn't support the weak subjectivity checkpoint api
+		if !errors.Is(err, ErrNotOK) {
+			return nil, errors.Wrap(err, "unexpected API response for prysm-only weak subjectivity checkpoint API")
+		}
+		// fall back to vanilla Beacon Node API method
+		return downloadBackwardsCompatible(ctx, client)
+	}
+	log.Printf("server weak subjectivity checkpoint response - epoch=%d, block_root=%#x, state_root=%#x", ws.Epoch, ws.BlockRoot, ws.StateRoot)
+
+	// use first slot of the epoch for the block slot
+	slot, err := slots.EpochStart(ws.Epoch)
+	if err != nil {
+		return nil, errors.Wrapf(err, "error computing first slot of epoch=%d", ws.Epoch)
+	}
+	log.Printf("requesting checkpoint state at slot %d", slot)
+
+	stateBytes, err := client.GetState(ctx, IdFromSlot(slot))
+	if err != nil {
+		return nil, errors.Wrapf(err, "failed to request state by slot from api, slot=%d", slot)
+	}
+	cf, err := detect.FromState(stateBytes)
+	if err != nil {
+		return nil, errors.Wrap(err, "error detecting chain config for beacon state")
+	}
+	log.Printf("detected supported config in checkpoint state, name=%s, fork=%s", cf.Config.ConfigName, version.String(cf.Fork))
+
+	state, err := cf.UnmarshalBeaconState(stateBytes)
+	if err != nil {
+		return nil, errors.Wrap(err, "error using detected config fork to unmarshal state bytes")
+	}
+	stateRoot, err := state.HashTreeRoot(ctx)
+	if err != nil {
+		return nil, errors.Wrapf(err, "failed to compute htr for state at slot=%d", slot)
+	}
+
+	blockRoot, err := state.LatestBlockHeader().HashTreeRoot()
+	if err != nil {
+		return nil, errors.Wrap(err, "error computing hash_tree_root of latest_block_header")
+	}
+	blockBytes, err := client.GetBlock(ctx, IdFromRoot(ws.BlockRoot))
+	if err != nil {
+		return nil, errors.Wrapf(err, "error requesting block by slot = %d", slot)
+	}
+	block, err := cf.UnmarshalBeaconBlock(blockBytes)
+	if err != nil {
+		return nil, errors.Wrap(err, "unable to unmarshal block to a supported type using the detected fork schedule")
+	}
+	realBlockRoot, err := block.Block().HashTreeRoot()
+	if err != nil {
+		return nil, errors.Wrap(err, "error computing hash_tree_root of retrieved block")
+	}
+	log.Printf("BeaconState slot=%d, Block slot=%d", state.Slot(), block.Block().Slot())
+	log.Printf("BeaconState htr=%#xd, Block state_root=%#x", stateRoot, block.Block().StateRoot())
+	log.Printf("BeaconState latest_block_header htr=%#xd, block htr=%#x", blockRoot, realBlockRoot)
+	return &OriginData{
+		wsd: ws,
+		st:  state,
+		b:   block,
+		sb:  stateBytes,
+		bb:  blockBytes,
+		cf:  cf,
+	}, nil
+}

api/client/beacon/checkpoint_test.go

@@ -0,0 +1,407 @@
+package beacon
+
+import (
+	"bytes"
+	"context"
+	"encoding/json"
+	"fmt"
+	"io"
+	"net/http"
+	"testing"
+
+	"github.com/prysmaticlabs/prysm/proto/prysm/v1alpha1/wrapper"
+
+	"github.com/prysmaticlabs/prysm/beacon-chain/state"
+	"github.com/prysmaticlabs/prysm/network/forks"
+	ethpb "github.com/prysmaticlabs/prysm/proto/prysm/v1alpha1"
+	"github.com/prysmaticlabs/prysm/testing/util"
+	"github.com/prysmaticlabs/prysm/time/slots"
+
+	types "github.com/prysmaticlabs/eth2-types"
+	"github.com/prysmaticlabs/prysm/config/params"
+	"github.com/prysmaticlabs/prysm/encoding/ssz/detect"
+	"github.com/prysmaticlabs/prysm/runtime/version"
+
+	"github.com/pkg/errors"
+	"github.com/prysmaticlabs/prysm/testing/require"
+)
+
+type testRT struct {
+	rt func(*http.Request) (*http.Response, error)
+}
+
+func (rt *testRT) RoundTrip(req *http.Request) (*http.Response, error) {
+	if rt.rt != nil {
+		return rt.rt(req)
+	}
+	return nil, errors.New("RoundTripper not implemented")
+}
+
+var _ http.RoundTripper = &testRT{}
+
+func marshalToEnvelope(val interface{}) ([]byte, error) {
+	raw, err := json.Marshal(val)
+	if err != nil {
+		return nil, errors.Wrap(err, "error marshaling value to place in data envelope")
+	}
+	env := struct {
+		Data json.RawMessage `json:"data"`
+	}{
+		Data: raw,
+	}
+	return json.Marshal(env)
+}
+
+func TestMarshalToEnvelope(t *testing.T) {
+	d := struct {
+		Version string `json:"version"`
+	}{
+		Version: "Prysm/v2.0.5 (linux amd64)",
+	}
+	encoded, err := marshalToEnvelope(d)
+	require.NoError(t, err)
+	expected := `{"data":{"version":"Prysm/v2.0.5 (linux amd64)"}}`
+	require.Equal(t, expected, string(encoded))
+}
+
+func TestFallbackVersionCheck(t *testing.T) {
+	c := &Client{
+		hc:     &http.Client{},
+		host:   "localhost:3500",
+		scheme: "http",
+	}
+	c.hc.Transport = &testRT{rt: func(req *http.Request) (*http.Response, error) {
+		res := &http.Response{Request: req}
+		switch req.URL.Path {
+		case getNodeVersionPath:
+			res.StatusCode = http.StatusOK
+			b := bytes.NewBuffer(nil)
+			d := struct {
+				Version string `json:"version"`
+			}{
+				Version: "Prysm/v2.0.5 (linux amd64)",
+			}
+			encoded, err := marshalToEnvelope(d)
+			require.NoError(t, err)
+			b.Write(encoded)
+			res.Body = io.NopCloser(b)
+		case getWeakSubjectivityPath:
+			res.StatusCode = http.StatusNotFound
+		}
+
+		return res, nil
+	}}
+
+	ctx := context.Background()
+	_, err := DownloadOriginData(ctx, c)
+	require.ErrorIs(t, err, ErrUnsupportedPrysmCheckpointVersion)
+}
+
+func TestFname(t *testing.T) {
+	vu := &detect.VersionedUnmarshaler{
+		Config: params.MainnetConfig(),
+		Fork:   version.Phase0,
+	}
+	slot := types.Slot(23)
+	prefix := "block"
+	var root [32]byte
+	copy(root[:], []byte{0x23, 0x23, 0x23})
+	expected := "block_mainnet_phase0_23-0x2323230000000000000000000000000000000000000000000000000000000000.ssz"
+	actual := fname(prefix, vu, slot, root)
+	require.Equal(t, expected, actual)
+
+	vu.Config = params.MinimalSpecConfig()
+	vu.Fork = version.Altair
+	slot = 17
+	prefix = "state"
+	copy(root[29:], []byte{0x17, 0x17, 0x17})
+	expected = "state_minimal_altair_17-0x2323230000000000000000000000000000000000000000000000000000171717.ssz"
+	actual = fname(prefix, vu, slot, root)
+	require.Equal(t, expected, actual)
+}
+
+func TestDownloadOriginData(t *testing.T) {
+	ctx := context.Background()
+	cfg := params.MainnetConfig()
+
+	epoch := cfg.AltairForkEpoch - 1
+	// set up checkpoint state, using the epoch that will be computed as the ws checkpoint state based on the head state
+	wSlot, err := slots.EpochStart(epoch)
+	require.NoError(t, err)
+	wst, err := util.NewBeaconState()
+	require.NoError(t, err)
+	fork, err := forkForEpoch(cfg, epoch)
+	require.NoError(t, wst.SetFork(fork))
+
+	// set up checkpoint block
+	b, err := wrapper.WrappedSignedBeaconBlock(util.NewBeaconBlock())
+	require.NoError(t, wrapper.SetBlockParentRoot(b, cfg.ZeroHash))
+	require.NoError(t, wrapper.SetBlockSlot(b, wSlot))
+	require.NoError(t, wrapper.SetProposerIndex(b, 0))
+
+	// set up state header pointing at checkpoint block - this is how the block is downloaded by root
+	header, err := b.Header()
+	require.NoError(t, err)
+	require.NoError(t, wst.SetLatestBlockHeader(header.Header))
+
+	// order of operations can be confusing here:
+	// - when computing the state root, make sure block header is complete, EXCEPT the state root should be zero-value
+	// - before computing the block root (to match the request route), the block should include the state root
+	//   *computed from the state with a header that does not have a state root set yet*
+	wRoot, err := wst.HashTreeRoot(ctx)
+	require.NoError(t, err)
+
+	require.NoError(t, wrapper.SetBlockStateRoot(b, wRoot))
+	serBlock, err := b.MarshalSSZ()
+	require.NoError(t, err)
+	bRoot, err := b.Block().HashTreeRoot()
+	require.NoError(t, err)
+
+	wsSerialized, err := wst.MarshalSSZ()
+	require.NoError(t, err)
+	expectedWSD := WeakSubjectivityData{
+		BlockRoot: bRoot,
+		StateRoot: wRoot,
+		Epoch:     epoch,
+	}
+
+	hc := &http.Client{
+		Transport: &testRT{rt: func(req *http.Request) (*http.Response, error) {
+			res := &http.Response{Request: req}
+			switch req.URL.Path {
+			case getWeakSubjectivityPath:
+				res.StatusCode = http.StatusOK
+				cp := struct {
+					Epoch string `json:"epoch"`
+					Root  string `json:"root"`
+				}{
+					Epoch: fmt.Sprintf("%d", slots.ToEpoch(b.Block().Slot())),
+					Root:  fmt.Sprintf("%#x", bRoot),
+				}
+				wsr := struct {
+					Checkpoint interface{} `json:"ws_checkpoint"`
+					StateRoot  string      `json:"state_root"`
+				}{
+					Checkpoint: cp,
+					StateRoot:  fmt.Sprintf("%#x", wRoot),
+				}
+				rb, err := marshalToEnvelope(wsr)
+				require.NoError(t, err)
+				res.Body = io.NopCloser(bytes.NewBuffer(rb))
+			case renderGetStatePath(IdFromSlot(wSlot)):
+				res.StatusCode = http.StatusOK
+				res.Body = io.NopCloser(bytes.NewBuffer(wsSerialized))
+			case renderGetBlockPath(IdFromRoot(bRoot)):
+				res.StatusCode = http.StatusOK
+				res.Body = io.NopCloser(bytes.NewBuffer(serBlock))
+			}
+
+			return res, nil
+		}},
+	}
+	c := &Client{
+		hc:     hc,
+		host:   "localhost:3500",
+		scheme: "http",
+	}
+
+	od, err := DownloadOriginData(ctx, c)
+	require.NoError(t, err)
+	require.Equal(t, expectedWSD.Epoch, od.wsd.Epoch)
+	require.Equal(t, expectedWSD.StateRoot, od.wsd.StateRoot)
+	require.Equal(t, expectedWSD.BlockRoot, od.wsd.BlockRoot)
+	require.DeepEqual(t, wsSerialized, od.sb)
+	require.DeepEqual(t, serBlock, od.bb)
+	require.DeepEqual(t, wst.Fork().CurrentVersion, od.cf.Version[:])
+	require.DeepEqual(t, version.Phase0, od.cf.Fork)
+}
+
+// runs downloadBackwardsCompatible directly
+// and via DownloadOriginData with a round tripper that triggers the backwards compatible code path
+func TestDownloadBackwardsCompatibleCombined(t *testing.T) {
+	ctx := context.Background()
+	cfg := params.MainnetConfig()
+
+	st, expectedEpoch := defaultTestHeadState(t, cfg)
+	serialized, err := st.MarshalSSZ()
+	require.NoError(t, err)
+
+	// set up checkpoint state, using the epoch that will be computed as the ws checkpoint state based on the head state
+	wSlot, err := slots.EpochStart(expectedEpoch)
+	require.NoError(t, err)
+	wst, err := util.NewBeaconState()
+	require.NoError(t, err)
+	fork, err := forkForEpoch(cfg, cfg.GenesisEpoch)
+	require.NoError(t, wst.SetFork(fork))
+
+	// set up checkpoint block
+	b, err := wrapper.WrappedSignedBeaconBlock(util.NewBeaconBlock())
+	require.NoError(t, wrapper.SetBlockParentRoot(b, cfg.ZeroHash))
+	require.NoError(t, wrapper.SetBlockSlot(b, wSlot))
+	require.NoError(t, wrapper.SetProposerIndex(b, 0))
+
+	// set up state header pointing at checkpoint block - this is how the block is downloaded by root
+	header, err := b.Header()
+	require.NoError(t, err)
+	require.NoError(t, wst.SetLatestBlockHeader(header.Header))
+
+	// order of operations can be confusing here:
+	// - when computing the state root, make sure block header is complete, EXCEPT the state root should be zero-value
+	// - before computing the block root (to match the request route), the block should include the state root
+	//   *computed from the state with a header that does not have a state root set yet*
+	wRoot, err := wst.HashTreeRoot(ctx)
+	require.NoError(t, err)
+
+	require.NoError(t, wrapper.SetBlockStateRoot(b, wRoot))
+	serBlock, err := b.MarshalSSZ()
+	require.NoError(t, err)
+	bRoot, err := b.Block().HashTreeRoot()
+	require.NoError(t, err)
+
+	wsSerialized, err := wst.MarshalSSZ()
+	require.NoError(t, err)
+
+	hc := &http.Client{
+		Transport: &testRT{rt: func(req *http.Request) (*http.Response, error) {
+			res := &http.Response{Request: req}
+			switch req.URL.Path {
+			case getNodeVersionPath:
+				res.StatusCode = http.StatusOK
+				b := bytes.NewBuffer(nil)
+				d := struct {
+					Version string `json:"version"`
+				}{
+					Version: "Lighthouse/v0.1.5 (Linux x86_64)",
+				}
+				encoded, err := marshalToEnvelope(d)
+				require.NoError(t, err)
+				b.Write(encoded)
+				res.Body = io.NopCloser(b)
+			case getWeakSubjectivityPath:
+				res.StatusCode = http.StatusNotFound
+			case renderGetStatePath(IdHead):
+				res.StatusCode = http.StatusOK
+				res.Body = io.NopCloser(bytes.NewBuffer(serialized))
+			case renderGetStatePath(IdFromSlot(wSlot)):
+				res.StatusCode = http.StatusOK
+				res.Body = io.NopCloser(bytes.NewBuffer(wsSerialized))
+			case renderGetBlockPath(IdFromRoot(bRoot)):
+				res.StatusCode = http.StatusOK
+				res.Body = io.NopCloser(bytes.NewBuffer(serBlock))
+			}
+
+			return res, nil
+		}},
+	}
+	c := &Client{
+		hc:     hc,
+		host:   "localhost:3500",
+		scheme: "http",
+	}
+
+	odPub, err := DownloadOriginData(ctx, c)
+	require.NoError(t, err)
+
+	odPriv, err := downloadBackwardsCompatible(ctx, c)
+	require.NoError(t, err)
+	require.DeepEqual(t, odPriv.wsd, odPub.wsd)
+	require.DeepEqual(t, odPriv.sb, odPub.sb)
+	require.DeepEqual(t, odPriv.bb, odPub.bb)
+	require.DeepEqual(t, odPriv.cf.Fork, odPub.cf.Fork)
+	require.DeepEqual(t, odPriv.cf.Version, odPub.cf.Version)
+}
+
+func TestGetWeakSubjectivityEpochFromHead(t *testing.T) {
+	st, expectedEpoch := defaultTestHeadState(t, params.MainnetConfig())
+	serialized, err := st.MarshalSSZ()
+	require.NoError(t, err)
+	hc := &http.Client{
+		Transport: &testRT{rt: func(req *http.Request) (*http.Response, error) {
+			res := &http.Response{Request: req}
+			switch req.URL.Path {
+			case renderGetStatePath(IdHead):
+				res.StatusCode = http.StatusOK
+				res.Body = io.NopCloser(bytes.NewBuffer(serialized))
+			}
+			return res, nil
+		}},
+	}
+	c := &Client{
+		hc:     hc,
+		host:   "localhost:3500",
+		scheme: "http",
+	}
+	actualEpoch, err := getWeakSubjectivityEpochFromHead(context.Background(), c)
+	require.NoError(t, err)
+	require.Equal(t, expectedEpoch, actualEpoch)
+}
+
+func forkForEpoch(cfg *params.BeaconChainConfig, epoch types.Epoch) (*ethpb.Fork, error) {
+	os := forks.NewOrderedSchedule(cfg)
+	currentVersion, err := os.VersionForEpoch(epoch)
+	if err != nil {
+		return nil, err
+	}
+	prevVersion, err := os.Previous(currentVersion)
+	if err != nil {
+		if !errors.Is(err, forks.ErrNoPreviousVersion) {
+			return nil, err
+		}
+		// use same version for both in the case of genesis
+		prevVersion = currentVersion
+	}
+	forkEpoch := cfg.ForkVersionSchedule[currentVersion]
+	return &ethpb.Fork{
+		PreviousVersion: prevVersion[:],
+		CurrentVersion:  currentVersion[:],
+		Epoch:           forkEpoch,
+	}, nil
+}
+
+func defaultTestHeadState(t *testing.T, cfg *params.BeaconChainConfig) (state.BeaconState, types.Epoch) {
+	st, err := util.NewBeaconStateAltair()
+	require.NoError(t, err)
+
+	fork, err := forkForEpoch(cfg, cfg.AltairForkEpoch)
+	require.NoError(t, err)
+	require.NoError(t, st.SetFork(fork))
+
+	slot, err := slots.EpochStart(cfg.AltairForkEpoch)
+	require.NoError(t, err)
+	require.NoError(t, st.SetSlot(slot))
+
+	var validatorCount, avgBalance uint64 = 100, 35
+	require.NoError(t, populateValidators(cfg, st, validatorCount, avgBalance))
+	require.NoError(t, st.SetFinalizedCheckpoint(&ethpb.Checkpoint{
+		Epoch: fork.Epoch - 10,
+		Root:  make([]byte, 32),
+	}))
+	// to see the math for this, look at helpers.LatestWeakSubjectivityEpoch
+	// and for the values use mainnet config values, the validatorCount and avgBalance above, and altair fork epoch
+	expectedEpoch := slots.ToEpoch(st.Slot()) - 224
+	return st, expectedEpoch
+}
+
+// TODO(10429): refactor beacon state options in testing/util to take a state.BeaconState so this can become an option
+func populateValidators(cfg *params.BeaconChainConfig, st state.BeaconState, valCount, avgBalance uint64) error {
+	validators := make([]*ethpb.Validator, valCount)
+	balances := make([]uint64, len(validators))
+	for i := uint64(0); i < valCount; i++ {
+		validators[i] = &ethpb.Validator{
+			PublicKey:             make([]byte, cfg.BLSPubkeyLength),
+			WithdrawalCredentials: make([]byte, 32),
+			EffectiveBalance:      avgBalance * 1e9,
+			ExitEpoch:             cfg.FarFutureEpoch,
+		}
+		balances[i] = validators[i].EffectiveBalance
+	}
+
+	if err := st.SetValidators(validators); err != nil {
+		return err
+	}
+	if err := st.SetBalances(balances); err != nil {
+		return err
+	}
+
+	return nil
+}

api/client/beacon/client.go

@@ -0,0 +1,437 @@
+package beacon
+
+import (
+	"bytes"
+	"context"
+	"encoding/json"
+	"fmt"
+	"io"
+	"io/ioutil"
+	"net"
+	"net/http"
+	"net/url"
+	"path"
+	"regexp"
+	"sort"
+	"strconv"
+	"text/template"
+	"time"
+
+	"github.com/prysmaticlabs/prysm/network/forks"
+
+	"github.com/ethereum/go-ethereum/common/hexutil"
+	"github.com/pkg/errors"
+	types "github.com/prysmaticlabs/eth2-types"
+	"github.com/prysmaticlabs/prysm/beacon-chain/rpc/apimiddleware"
+	"github.com/prysmaticlabs/prysm/encoding/bytesutil"
+	ethpb "github.com/prysmaticlabs/prysm/proto/prysm/v1alpha1"
+	log "github.com/sirupsen/logrus"
+)
+
+const (
+	getSignedBlockPath      = "/eth/v2/beacon/blocks"
+	getBlockRootPath        = "/eth/v1/beacon/blocks/{{.Id}}/root"
+	getForkForStatePath     = "/eth/v1/beacon/states/{{.Id}}/fork"
+	getWeakSubjectivityPath = "/eth/v1/beacon/weak_subjectivity"
+	getForkSchedulePath     = "/eth/v1/config/fork_schedule"
+	getStatePath            = "/eth/v2/debug/beacon/states"
+	getNodeVersionPath      = "/eth/v1/node/version"
+)
+
+// StateOrBlockId represents the block_id / state_id parameters that several of the Eth Beacon API methods accept.
+// StateOrBlockId constants are defined for named identifiers, and helper methods are provided
+// for slot and root identifiers. Example text from the Eth Beacon Node API documentation:
+//
+// "Block identifier can be one of: "head" (canonical head in node's view), "genesis", "finalized",
+// <slot>, <hex encoded blockRoot with 0x prefix>."
+type StateOrBlockId string
+
+const (
+	IdFinalized StateOrBlockId = "finalized"
+	IdGenesis   StateOrBlockId = "genesis"
+	IdHead      StateOrBlockId = "head"
+	IdJustified StateOrBlockId = "justified"
+)
+
+// IdFromRoot encodes a block root in the format expected by the API in places where a root can be used to identify
+// a BeaconState or SignedBeaconBlock.
+func IdFromRoot(r [32]byte) StateOrBlockId {
+	return StateOrBlockId(fmt.Sprintf("%#x", r))
+}
+
+// IdFromRoot encodes a Slot in the format expected by the API in places where a slot can be used to identify
+// a BeaconState or SignedBeaconBlock.
+func IdFromSlot(s types.Slot) StateOrBlockId {
+	return StateOrBlockId(strconv.FormatUint(uint64(s), 10))
+}
+
+// idTemplate is used to create template functions that can interpolate StateOrBlockId values.
+func idTemplate(ts string) func(StateOrBlockId) string {
+	t := template.Must(template.New("").Parse(ts))
+	f := func(id StateOrBlockId) string {
+		b := bytes.NewBuffer(nil)
+		err := t.Execute(b, struct{ Id string }{Id: string(id)})
+		if err != nil {
+			panic(fmt.Sprintf("invalid idTemplate: %s", ts))
+		}
+		return b.String()
+	}
+	// run the template to ensure that it is valid
+	// this should happen load time (using package scoped vars) to ensure runtime errors aren't possible
+	_ = f(IdGenesis)
+	return f
+}
+
+// ClientOpt is a functional option for the Client type (http.Client wrapper)
+type ClientOpt func(*Client)
+
+// WithTimeout sets the .Timeout attribute of the wrapped http.Client.
+func WithTimeout(timeout time.Duration) ClientOpt {
+	return func(c *Client) {
+		c.hc.Timeout = timeout
+	}
+}
+
+// Client provides a collection of helper methods for calling the Eth Beacon Node API endpoints.
+type Client struct {
+	hc     *http.Client
+	host   string
+	scheme string
+}
+
+// NewClient constructs a new client with the provided options (ex WithTimeout).
+// `host` is the base host + port used to construct request urls. This value can be
+// a URL string, or NewClient will assume an http endpoint if just `host:port` is used.
+func NewClient(host string, opts ...ClientOpt) (*Client, error) {
+	host, err := validHostname(host)
+	if err != nil {
+		return nil, err
+	}
+	c := &Client{
+		hc:     &http.Client{},
+		scheme: "http",
+		host:   host,
+	}
+	for _, o := range opts {
+		o(c)
+	}
+	return c, nil
+}
+
+func validHostname(h string) (string, error) {
+	// try to parse as url (being permissive)
+	u, err := url.Parse(h)
+	if err == nil && u.Host != "" {
+		return u.Host, nil
+	}
+	// try to parse as host:port
+	host, port, err := net.SplitHostPort(h)
+	if err != nil {
+		return "", err
+	}
+	return fmt.Sprintf("%s:%s", host, port), nil
+}
+
+func (c *Client) urlForPath(methodPath string) *url.URL {
+	u := &url.URL{
+		Scheme: c.scheme,
+		Host:   c.host,
+	}
+	u.Path = path.Join(u.Path, methodPath)
+	return u
+}
+
+type reqOption func(*http.Request)
+
+func withSSZEncoding() reqOption {
+	return func(req *http.Request) {
+		req.Header.Set("Accept", "application/octet-stream")
+	}
+}
+
+// get is a generic, opinionated GET function to reduce boilerplate amongst the getters in this package.
+func (c *Client) get(ctx context.Context, path string, opts ...reqOption) ([]byte, error) {
+	u := c.urlForPath(path)
+	log.Printf("requesting %s", u.String())
+	req, err := http.NewRequestWithContext(ctx, http.MethodGet, u.String(), nil)
+	if err != nil {
+		return nil, err
+	}
+	for _, o := range opts {
+		o(req)
+	}
+	r, err := c.hc.Do(req)
+	if err != nil {
+		return nil, err
+	}
+	defer func() {
+		err = r.Body.Close()
+	}()
+	if r.StatusCode != http.StatusOK {
+		return nil, non200Err(r)
+	}
+	b, err := io.ReadAll(r.Body)
+	if err != nil {
+		return nil, errors.Wrap(err, "error reading http response body from GetBlock")
+	}
+	return b, nil
+}
+
+func renderGetBlockPath(id StateOrBlockId) string {
+	return path.Join(getSignedBlockPath, string(id))
+}
+
+// GetBlock retrieves the SignedBeaconBlock for the given block id.
+// Block identifier can be one of: "head" (canonical head in node's view), "genesis", "finalized",
+// <slot>, <hex encoded blockRoot with 0x prefix>. Variables of type StateOrBlockId are exported by this package
+// for the named identifiers.
+// The return value contains the ssz-encoded bytes.
+func (c *Client) GetBlock(ctx context.Context, blockId StateOrBlockId) ([]byte, error) {
+	blockPath := renderGetBlockPath(blockId)
+	b, err := c.get(ctx, blockPath, withSSZEncoding())
+	if err != nil {
+		return nil, errors.Wrapf(err, "error requesting state by id = %s", blockId)
+	}
+	return b, nil
+}
+
+var getBlockRootTpl = idTemplate(getBlockRootPath)
+
+// GetBlockRoot retrieves the hash_tree_root of the BeaconBlock for the given block id.
+// Block identifier can be one of: "head" (canonical head in node's view), "genesis", "finalized",
+// <slot>, <hex encoded blockRoot with 0x prefix>. Variables of type StateOrBlockId are exported by this package
+// for the named identifiers.
+func (c *Client) GetBlockRoot(ctx context.Context, blockId StateOrBlockId) ([32]byte, error) {
+	rootPath := getBlockRootTpl(blockId)
+	b, err := c.get(ctx, rootPath)
+	if err != nil {
+		return [32]byte{}, errors.Wrapf(err, "error requesting block root by id = %s", blockId)
+	}
+	jsonr := &struct{ Data struct{ Root string } }{}
+	err = json.Unmarshal(b, jsonr)
+	if err != nil {
+		return [32]byte{}, errors.Wrap(err, "error decoding json data from get block root response")
+	}
+	rs, err := hexutil.Decode(jsonr.Data.Root)
+	if err != nil {
+		return [32]byte{}, errors.Wrap(err, fmt.Sprintf("error decoding hex-encoded value %s", jsonr.Data.Root))
+	}
+	return bytesutil.ToBytes32(rs), nil
+}
+
+var getForkTpl = idTemplate(getForkForStatePath)
+
+// GetFork queries the Beacon Node API for the Fork from the state identified by stateId.
+// Block identifier can be one of: "head" (canonical head in node's view), "genesis", "finalized",
+// <slot>, <hex encoded blockRoot with 0x prefix>. Variables of type StateOrBlockId are exported by this package
+// for the named identifiers.
+func (c *Client) GetFork(ctx context.Context, stateId StateOrBlockId) (*ethpb.Fork, error) {
+	body, err := c.get(ctx, getForkTpl(stateId))
+	if err != nil {
+		return nil, errors.Wrapf(err, "error requesting fork by state id = %s", stateId)
+	}
+	fr := &forkResponse{}
+	dataWrapper := &struct{ Data *forkResponse }{Data: fr}
+	err = json.Unmarshal(body, dataWrapper)
+	if err != nil {
+		return nil, errors.Wrap(err, "error decoding json response in GetFork")
+	}
+
+	return fr.Fork()
+}
+
+// GetForkSchedule retrieve all forks, past present and future, of which this node is aware.
+func (c *Client) GetForkSchedule(ctx context.Context) (forks.OrderedSchedule, error) {
+	body, err := c.get(ctx, getForkSchedulePath)
+	if err != nil {
+		return nil, errors.Wrap(err, "error requesting fork schedule")
+	}
+	fsr := &forkScheduleResponse{}
+	err = json.Unmarshal(body, fsr)
+	if err != nil {
+		return nil, err
+	}
+	ofs, err := fsr.OrderedForkSchedule()
+	if err != nil {
+		return nil, errors.Wrap(err, fmt.Sprintf("problem unmarshaling %s response", getForkSchedulePath))
+	}
+	return ofs, nil
+}
+
+type NodeVersion struct {
+	implementation string
+	semver         string
+	systemInfo     string
+}
+
+var versionRE = regexp.MustCompile(`^(\w+)\/(v\d+\.\d+\.\d+) \((.*)\)$`)
+
+func parseNodeVersion(v string) (*NodeVersion, error) {
+	groups := versionRE.FindStringSubmatch(v)
+	if len(groups) != 4 {
+		return nil, errors.Wrapf(ErrInvalidNodeVersion, "could not be parsed: %s", v)
+	}
+	return &NodeVersion{
+		implementation: groups[1],
+		semver:         groups[2],
+		systemInfo:     groups[3],
+	}, nil
+}
+
+// GetNodeVersion requests that the beacon node identify information about its implementation in a format
+// similar to a HTTP User-Agent field. ex: Lighthouse/v0.1.5 (Linux x86_64)
+func (c *Client) GetNodeVersion(ctx context.Context) (*NodeVersion, error) {
+	b, err := c.get(ctx, getNodeVersionPath)
+	if err != nil {
+		return nil, errors.Wrap(err, "error requesting node version")
+	}
+	d := struct {
+		Data struct {
+			Version string `json:"version"`
+		} `json:"data"`
+	}{}
+	err = json.Unmarshal(b, &d)
+	if err != nil {
+		return nil, errors.Wrapf(err, "error unmarshaling response body: %s", string(b))
+	}
+	return parseNodeVersion(d.Data.Version)
+}
+
+func renderGetStatePath(id StateOrBlockId) string {
+	return path.Join(getStatePath, string(id))
+}
+
+// GetState retrieves the BeaconState for the given state id.
+// State identifier can be one of: "head" (canonical head in node's view), "genesis", "finalized",
+// <slot>, <hex encoded stateRoot with 0x prefix>. Variables of type StateOrBlockId are exported by this package
+// for the named identifiers.
+// The return value contains the ssz-encoded bytes.
+func (c *Client) GetState(ctx context.Context, stateId StateOrBlockId) ([]byte, error) {
+	statePath := path.Join(getStatePath, string(stateId))
+	b, err := c.get(ctx, statePath, withSSZEncoding())
+	if err != nil {
+		return nil, errors.Wrapf(err, "error requesting state by id = %s", stateId)
+	}
+	return b, nil
+}
+
+// GetWeakSubjectivity calls a proposed API endpoint that is unique to prysm
+// This api method does the following:
+// - computes weak subjectivity epoch
+// - finds the highest non-skipped block preceding the epoch
+// - returns the htr of the found block and returns this + the value of state_root from the block
+func (c *Client) GetWeakSubjectivity(ctx context.Context) (*WeakSubjectivityData, error) {
+	body, err := c.get(ctx, getWeakSubjectivityPath)
+	if err != nil {
+		return nil, err
+	}
+	v := &apimiddleware.WeakSubjectivityResponse{}
+	err = json.Unmarshal(body, v)
+	if err != nil {
+		return nil, err
+	}
+	epoch, err := strconv.ParseUint(v.Data.Checkpoint.Epoch, 10, 64)
+	if err != nil {
+		return nil, err
+	}
+	blockRoot, err := hexutil.Decode(v.Data.Checkpoint.Root)
+	if err != nil {
+		return nil, err
+	}
+	stateRoot, err := hexutil.Decode(v.Data.StateRoot)
+	if err != nil {
+		return nil, err
+	}
+	return &WeakSubjectivityData{
+		Epoch:     types.Epoch(epoch),
+		BlockRoot: bytesutil.ToBytes32(blockRoot),
+		StateRoot: bytesutil.ToBytes32(stateRoot),
+	}, nil
+}
+
+// WeakSubjectivityData represents the state root, block root and epoch of the BeaconState + SignedBeaconBlock
+// that falls at the beginning of the current weak subjectivity period. These values can be used to construct
+// a weak subjectivity checkpoint, or to download a BeaconState+SignedBeaconBlock pair that can be used to bootstrap
+// a new Beacon Node using Checkpoint Sync.
+type WeakSubjectivityData struct {
+	BlockRoot [32]byte
+	StateRoot [32]byte
+	Epoch     types.Epoch
+}
+
+func non200Err(response *http.Response) error {
+	bodyBytes, err := ioutil.ReadAll(response.Body)
+	var body string
+	if err != nil {
+		body = "(Unable to read response body.)"
+	} else {
+		body = "response body:\n" + string(bodyBytes)
+	}
+	msg := fmt.Sprintf("code=%d, url=%s, body=%s", response.StatusCode, response.Request.URL, body)
+	switch response.StatusCode {
+	case 404:
+		return errors.Wrap(ErrNotFound, msg)
+	default:
+		return errors.Wrap(ErrNotOK, msg)
+	}
+}
+
+type forkResponse struct {
+	PreviousVersion string `json:"previous_version"`
+	CurrentVersion  string `json:"current_version"`
+	Epoch           string `json:"epoch"`
+}
+
+func (f *forkResponse) Fork() (*ethpb.Fork, error) {
+	epoch, err := strconv.ParseUint(f.Epoch, 10, 64)
+	if err != nil {
+		return nil, err
+	}
+	cSlice, err := hexutil.Decode(f.CurrentVersion)
+	if err != nil {
+		return nil, err
+	}
+	if len(cSlice) != 4 {
+		return nil, fmt.Errorf("got %d byte version for CurrentVersion, expected 4 bytes. hex=%s", len(cSlice), f.CurrentVersion)
+	}
+	pSlice, err := hexutil.Decode(f.PreviousVersion)
+	if err != nil {
+		return nil, err
+	}
+	if len(pSlice) != 4 {
+		return nil, fmt.Errorf("got %d byte version, expected 4 bytes. version hex=%s", len(pSlice), f.PreviousVersion)
+	}
+	return &ethpb.Fork{
+		CurrentVersion:  cSlice,
+		PreviousVersion: pSlice,
+		Epoch:           types.Epoch(epoch),
+	}, nil
+}
+
+type forkScheduleResponse struct {
+	Data []forkResponse
+}
+
+func (fsr *forkScheduleResponse) OrderedForkSchedule() (forks.OrderedSchedule, error) {
+	ofs := make(forks.OrderedSchedule, 0)
+	for _, d := range fsr.Data {
+		epoch, err := strconv.Atoi(d.Epoch)
+		if err != nil {
+			return nil, err
+		}
+		vSlice, err := hexutil.Decode(d.CurrentVersion)
+		if err != nil {
+			return nil, err
+		}
+		if len(vSlice) != 4 {
+			return nil, fmt.Errorf("got %d byte version, expected 4 bytes. version hex=%s", len(vSlice), d.CurrentVersion)
+		}
+		version := bytesutil.ToBytes4(vSlice)
+		ofs = append(ofs, forks.ForkScheduleEntry{
+			Version: version,
+			Epoch:   types.Epoch(uint64(epoch)),
+		})
+	}
+	sort.Sort(ofs)
+	return ofs, nil
+}

api/client/beacon/client_test.go

@@ -0,0 +1,58 @@
+package beacon
+
+import (
+	"testing"
+
+	"github.com/prysmaticlabs/prysm/testing/require"
+)
+
+func TestParseNodeVersion(t *testing.T) {
+	cases := []struct {
+		name string
+		v    string
+		err  error
+		nv   *NodeVersion
+	}{
+		{
+			name: "empty string",
+			v:    "",
+			err:  ErrInvalidNodeVersion,
+		},
+		{
+			name: "Prysm as the version string",
+			v:    "Prysm",
+			err:  ErrInvalidNodeVersion,
+		},
+		{
+			name: "semver only",
+			v:    "v2.0.6",
+			err:  ErrInvalidNodeVersion,
+		},
+		{
+			name: "implementation and semver only",
+			v:    "Prysm/v2.0.6",
+			err:  ErrInvalidNodeVersion,
+		},
+		{
+			name: "complete version",
+			v:    "Prysm/v2.0.6 (linux amd64)",
+			nv: &NodeVersion{
+				implementation: "Prysm",
+				semver:         "v2.0.6",
+				systemInfo:     "linux amd64",
+			},
+		},
+	}
+
+	for _, c := range cases {
+		t.Run(c.name, func(t *testing.T) {
+			nv, err := parseNodeVersion(c.v)
+			if c.err != nil {
+				require.ErrorIs(t, err, c.err)
+			} else {
+				require.NoError(t, err)
+				require.DeepEqual(t, c.nv, nv)
+			}
+		})
+	}
+}

api/client/beacon/doc.go

@@ -0,0 +1,6 @@
+/*
+Package beacon provides a client for interacting with the standard Eth Beacon Node API.
+Interactive swagger documentation for the API is available here: https://ethereum.github.io/beacon-APIs/
+
+*/
+package beacon

api/client/beacon/errors.go

@@ -0,0 +1,13 @@
+package beacon
+
+import "github.com/pkg/errors"
+
+// ErrNotOK is used to indicate when an HTTP request to the Beacon Node API failed with any non-2xx response code.
+// More specific errors may be returned, but an error in reaction to a non-2xx response will always wrap ErrNotOK.
+var ErrNotOK = errors.New("did not receive 2xx response from API")
+
+// ErrNotFound specifically means that a '404 - NOT FOUND' response was received from the API.
+var ErrNotFound = errors.Wrap(ErrNotOK, "recv 404 NotFound response from API")
+
+// ErrInvalidNodeVersion indicates that the /eth/v1/node/version api response format was not recognized.
+var ErrInvalidNodeVersion = errors.New("invalid node version response")

async/multilock_test.go

@@ -110,9 +110,8 @@ func TestLockUnlock_CleansUnused(t *testing.T) {
 		lock := NewMultilock("dog", "cat", "owl")
 		lock.Lock()
 		assert.Equal(t, 3, len(locks.list))
-		defer lock.Unlock()
+		lock.Unlock()
 
-		<-time.After(100 * time.Millisecond)
 		wg.Done()
 	}()
 	wg.Wait()

beacon-chain/blockchain/BUILD.bazel

@@ -7,7 +7,6 @@ go_library(
         "error.go",
         "head.go",
         "head_sync_committee_info.go",
-        "info.go",
         "init_sync_process_block.go",
         "log.go",
         "metrics.go",
@@ -50,7 +49,9 @@ go_library(
         "//beacon-chain/db:go_default_library",
         "//beacon-chain/db/filters:go_default_library",
         "//beacon-chain/forkchoice:go_default_library",
+        "//beacon-chain/forkchoice/doubly-linked-tree:go_default_library",
         "//beacon-chain/forkchoice/protoarray:go_default_library",
+        "//beacon-chain/forkchoice/types:go_default_library",
         "//beacon-chain/operations/attestations:go_default_library",
         "//beacon-chain/operations/slashings:go_default_library",
         "//beacon-chain/operations/voluntaryexits:go_default_library",
@@ -74,7 +75,6 @@ go_library(
         "//runtime/version:go_default_library",
         "//time:go_default_library",
         "//time/slots:go_default_library",
-        "@com_github_emicklei_dot//:go_default_library",
         "@com_github_ethereum_go_ethereum//common:go_default_library",
         "@com_github_ethereum_go_ethereum//common/hexutil:go_default_library",
         "@com_github_holiman_uint256//:go_default_library",
@@ -104,7 +104,6 @@ go_test(
         "checktags_test.go",
         "head_sync_committee_info_test.go",
         "head_test.go",
-        "info_test.go",
         "init_test.go",
         "log_test.go",
         "metrics_test.go",

beacon-chain/blockchain/chain_info.go

@@ -6,6 +6,8 @@ import (
 
 	types "github.com/prysmaticlabs/eth2-types"
 	"github.com/prysmaticlabs/prysm/beacon-chain/core/helpers"
+	"github.com/prysmaticlabs/prysm/beacon-chain/forkchoice"
+	doublylinkedtree "github.com/prysmaticlabs/prysm/beacon-chain/forkchoice/doubly-linked-tree"
 	"github.com/prysmaticlabs/prysm/beacon-chain/forkchoice/protoarray"
 	"github.com/prysmaticlabs/prysm/beacon-chain/state"
 	fieldparams "github.com/prysmaticlabs/prysm/config/fieldparams"
@@ -53,12 +55,12 @@ type HeadFetcher interface {
 	HeadETH1Data() *ethpb.Eth1Data
 	HeadPublicKeyToValidatorIndex(pubKey [fieldparams.BLSPubkeyLength]byte) (types.ValidatorIndex, bool)
 	HeadValidatorIndexToPublicKey(ctx context.Context, index types.ValidatorIndex) ([fieldparams.BLSPubkeyLength]byte, error)
-	ProtoArrayStore() *protoarray.Store
 	ChainHeads() ([][32]byte, []types.Slot)
 	IsOptimistic(ctx context.Context) (bool, error)
-	IsOptimisticForRoot(ctx context.Context, root [32]byte, slot types.Slot) (bool, error)
+	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.
@@ -238,11 +240,6 @@ func (s *Service) HeadETH1Data() *ethpb.Eth1Data {
 	return s.head.state.Eth1Data()
 }
 
-// ProtoArrayStore returns the proto array store object.
-func (s *Service) ProtoArrayStore() *protoarray.Store {
-	return s.cfg.ForkChoiceStore.Store()
-}
-
 // GenesisTime returns the genesis time of beacon chain.
 func (s *Service) GenesisTime() time.Time {
 	return s.genesisTime
@@ -288,23 +285,7 @@ func (s *Service) IsCanonical(ctx context.Context, blockRoot [32]byte) (bool, er
 // ChainHeads returns all possible chain heads (leaves of fork choice tree).
 // Heads roots and heads slots are returned.
 func (s *Service) ChainHeads() ([][32]byte, []types.Slot) {
-	nodes := s.ProtoArrayStore().Nodes()
-
-	// Deliberate choice to not preallocate space for below.
-	// Heads cant be more than 2-3 in the worst case where pre-allocation will be 64 to begin with.
-	headsRoots := make([][32]byte, 0)
-	headsSlots := make([]types.Slot, 0)
-
-	nonExistentNode := ^uint64(0)
-	for _, node := range nodes {
-		// Possible heads have no children.
-		if node.BestDescendant() == nonExistentNode && node.BestChild() == nonExistentNode {
-			headsRoots = append(headsRoots, node.Root())
-			headsSlots = append(headsSlots, node.Slot())
-		}
-	}
-
-	return headsRoots, headsSlots
+	return s.cfg.ForkChoiceStore.Tips()
 }
 
 // HeadPublicKeyToValidatorIndex returns the validator index of the `pubkey` in current head state.
@@ -331,6 +312,11 @@ func (s *Service) HeadValidatorIndexToPublicKey(_ context.Context, index types.V
 	return v.PublicKey(), nil
 }
 
+// ForkChoicer returns the forkchoice interface
+func (s *Service) ForkChoicer() forkchoice.ForkChoicer {
+	return s.cfg.ForkChoiceStore
+}
+
 // IsOptimistic returns true if the current head is optimistic.
 func (s *Service) IsOptimistic(ctx context.Context) (bool, error) {
 	s.headLock.RLock()
@@ -339,16 +325,52 @@ func (s *Service) IsOptimistic(ctx context.Context) (bool, error) {
 		return false, nil
 	}
 
-	return s.cfg.ForkChoiceStore.Optimistic(ctx, s.head.root, s.head.slot)
+	return s.IsOptimisticForRoot(ctx, s.head.root)
 }
 
 // IsOptimisticForRoot takes the root and slot as aguments instead of the current head
 // and returns true if it is optimistic.
-func (s *Service) IsOptimisticForRoot(ctx context.Context, root [32]byte, slot types.Slot) (bool, error) {
-	return s.cfg.ForkChoiceStore.Optimistic(ctx, root, slot)
+func (s *Service) IsOptimisticForRoot(ctx context.Context, root [32]byte) (bool, error) {
+	optimistic, err := s.cfg.ForkChoiceStore.IsOptimistic(ctx, root)
+	if err == nil {
+		return optimistic, nil
+	}
+	if err != protoarray.ErrUnknownNodeRoot && err != doublylinkedtree.ErrNilNode {
+		return false, err
+	}
+	ss, err := s.cfg.BeaconDB.StateSummary(ctx, root)
+	if err != nil {
+		return false, err
+	}
+	if ss == nil {
+		return false, errInvalidNilSummary
+	}
+
+	validatedCheckpoint, err := s.cfg.BeaconDB.LastValidatedCheckpoint(ctx)
+	if err != nil {
+		return false, err
+	}
+	if slots.ToEpoch(ss.Slot) > validatedCheckpoint.Epoch {
+		return true, nil
+	}
+
+	if slots.ToEpoch(ss.Slot)+1 < validatedCheckpoint.Epoch {
+		return false, nil
+	}
+
+	lastValidated, err := s.cfg.BeaconDB.StateSummary(ctx, bytesutil.ToBytes32(validatedCheckpoint.Root))
+	if err != nil {
+		return false, err
+	}
+	return ss.Slot > lastValidated.Slot, nil
 }
 
 // SetGenesisTime sets the genesis time of beacon chain.
 func (s *Service) SetGenesisTime(t time.Time) {
 	s.genesisTime = t
 }
+
+// ForkChoiceStore returns the fork choice store in the service
+func (s *Service) ForkChoiceStore() forkchoice.ForkChoicer {
+	return s.cfg.ForkChoiceStore
+}

beacon-chain/blockchain/chain_info_norace_test.go

@@ -16,10 +16,13 @@ func TestHeadSlot_DataRace(t *testing.T) {
 	s := &Service{
 		cfg: &config{BeaconDB: beaconDB},
 	}
+	wait := make(chan struct{})
 	go func() {
+		defer close(wait)
 		require.NoError(t, s.saveHead(context.Background(), [32]byte{}))
 	}()
 	s.HeadSlot()
+	<-wait
 }
 
 func TestHeadRoot_DataRace(t *testing.T) {
@@ -28,24 +31,32 @@ func TestHeadRoot_DataRace(t *testing.T) {
 		cfg:  &config{BeaconDB: beaconDB, StateGen: stategen.New(beaconDB)},
 		head: &head{root: [32]byte{'A'}},
 	}
+	wait := make(chan struct{})
 	go func() {
+		defer close(wait)
 		require.NoError(t, s.saveHead(context.Background(), [32]byte{}))
 	}()
 	_, err := s.HeadRoot(context.Background())
 	require.NoError(t, err)
+	<-wait
 }
 
 func TestHeadBlock_DataRace(t *testing.T) {
 	beaconDB := testDB.SetupDB(t)
+	wsb, err := wrapper.WrappedSignedBeaconBlock(&ethpb.SignedBeaconBlock{})
+	require.NoError(t, err)
 	s := &Service{
 		cfg:  &config{BeaconDB: beaconDB, StateGen: stategen.New(beaconDB)},
-		head: &head{block: wrapper.WrappedPhase0SignedBeaconBlock(&ethpb.SignedBeaconBlock{})},
+		head: &head{block: wsb},
 	}
+	wait := make(chan struct{})
 	go func() {
+		defer close(wait)
 		require.NoError(t, s.saveHead(context.Background(), [32]byte{}))
 	}()
-	_, err := s.HeadBlock(context.Background())
+	_, err = s.HeadBlock(context.Background())
 	require.NoError(t, err)
+	<-wait
 }
 
 func TestHeadState_DataRace(t *testing.T) {
@@ -53,9 +64,12 @@ func TestHeadState_DataRace(t *testing.T) {
 	s := &Service{
 		cfg: &config{BeaconDB: beaconDB, StateGen: stategen.New(beaconDB)},
 	}
+	wait := make(chan struct{})
 	go func() {
+		defer close(wait)
 		require.NoError(t, s.saveHead(context.Background(), [32]byte{}))
 	}()
 	_, err := s.HeadState(context.Background())
 	require.NoError(t, err)
+	<-wait
 }

beacon-chain/blockchain/chain_info_test.go

@@ -8,6 +8,7 @@ import (
 	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"
 	v1 "github.com/prysmaticlabs/prysm/beacon-chain/state/v1"
 	fieldparams "github.com/prysmaticlabs/prysm/config/fieldparams"
@@ -40,6 +41,12 @@ func TestHeadRoot_Nil(t *testing.T) {
 	assert.DeepEqual(t, params.BeaconConfig().ZeroHash[:], headRoot, "Incorrect pre chain start value")
 }
 
+func TestService_ForkChoiceStore(t *testing.T) {
+	c := &Service{cfg: &config{ForkChoiceStore: doublylinkedtree.New(0, 0)}}
+	p := c.ForkChoiceStore()
+	require.Equal(t, 0, int(p.FinalizedEpoch()))
+}
+
 func TestFinalizedCheckpt_CanRetrieve(t *testing.T) {
 	beaconDB := testDB.SetupDB(t)
 
@@ -126,7 +133,9 @@ func TestHeadRoot_UseDB(t *testing.T) {
 	b := util.NewBeaconBlock()
 	br, err := b.Block.HashTreeRoot()
 	require.NoError(t, err)
-	require.NoError(t, beaconDB.SaveBlock(context.Background(), wrapper.WrappedPhase0SignedBeaconBlock(b)))
+	wsb, err := wrapper.WrappedSignedBeaconBlock(b)
+	require.NoError(t, err)
+	require.NoError(t, beaconDB.SaveBlock(context.Background(), wsb))
 	require.NoError(t, beaconDB.SaveStateSummary(context.Background(), &ethpb.StateSummary{Root: br[:]}))
 	require.NoError(t, beaconDB.SaveHeadBlockRoot(context.Background(), br))
 	r, err := c.HeadRoot(context.Background())
@@ -139,8 +148,10 @@ func TestHeadBlock_CanRetrieve(t *testing.T) {
 	b.Block.Slot = 1
 	s, err := v1.InitializeFromProto(&ethpb.BeaconState{})
 	require.NoError(t, err)
+	wsb, err := wrapper.WrappedSignedBeaconBlock(b)
+	require.NoError(t, err)
 	c := &Service{}
-	c.head = &head{block: wrapper.WrappedPhase0SignedBeaconBlock(b), state: s}
+	c.head = &head{block: wsb, state: s}
 
 	recevied, err := c.HeadBlock(context.Background())
 	require.NoError(t, err)
@@ -222,7 +233,9 @@ func TestIsCanonical_Ok(t *testing.T) {
 	blk.Block.Slot = 0
 	root, err := blk.Block.HashTreeRoot()
 	require.NoError(t, err)
-	require.NoError(t, beaconDB.SaveBlock(ctx, wrapper.WrappedPhase0SignedBeaconBlock(blk)))
+	wsb, err := wrapper.WrappedSignedBeaconBlock(blk)
+	require.NoError(t, err)
+	require.NoError(t, beaconDB.SaveBlock(ctx, wsb))
 	require.NoError(t, beaconDB.SaveGenesisBlockRoot(ctx, root))
 	can, err := c.IsCanonical(ctx, root)
 	require.NoError(t, err)
@@ -277,27 +290,40 @@ func TestService_HeadGenesisValidatorsRoot(t *testing.T) {
 	root = c.HeadGenesisValidatorsRoot()
 	require.DeepEqual(t, root[:], s.GenesisValidatorsRoot())
 }
-
-func TestService_ProtoArrayStore(t *testing.T) {
-	c := &Service{cfg: &config{ForkChoiceStore: protoarray.New(0, 0, [32]byte{})}}
-	p := c.ProtoArrayStore()
-	require.Equal(t, 0, int(p.FinalizedEpoch()))
-}
-
-func TestService_ChainHeads(t *testing.T) {
+func TestService_ChainHeads_ProtoArray(t *testing.T) {
 	ctx := context.Background()
-	c := &Service{cfg: &config{ForkChoiceStore: protoarray.New(0, 0, [32]byte{})}}
-	require.NoError(t, c.cfg.ForkChoiceStore.ProcessBlock(ctx, 100, [32]byte{'a'}, [32]byte{}, [32]byte{}, 0, 0))
-	require.NoError(t, c.cfg.ForkChoiceStore.ProcessBlock(ctx, 101, [32]byte{'b'}, [32]byte{'a'}, [32]byte{}, 0, 0))
-	require.NoError(t, c.cfg.ForkChoiceStore.ProcessBlock(ctx, 102, [32]byte{'c'}, [32]byte{'b'}, [32]byte{}, 0, 0))
-	require.NoError(t, c.cfg.ForkChoiceStore.ProcessBlock(ctx, 103, [32]byte{'d'}, [32]byte{}, [32]byte{}, 0, 0))
-	require.NoError(t, c.cfg.ForkChoiceStore.ProcessBlock(ctx, 104, [32]byte{'e'}, [32]byte{'b'}, [32]byte{}, 0, 0))
+	c := &Service{cfg: &config{ForkChoiceStore: protoarray.New(0, 0,
+		params.BeaconConfig().ZeroHash)}}
+	require.NoError(t, c.cfg.ForkChoiceStore.InsertOptimisticBlock(ctx, 100, [32]byte{'a'}, [32]byte{}, params.BeaconConfig().ZeroHash, 0, 0))
+	require.NoError(t, c.cfg.ForkChoiceStore.InsertOptimisticBlock(ctx, 101, [32]byte{'b'}, [32]byte{'a'}, params.BeaconConfig().ZeroHash, 0, 0))
+	require.NoError(t, c.cfg.ForkChoiceStore.InsertOptimisticBlock(ctx, 102, [32]byte{'c'}, [32]byte{'b'}, params.BeaconConfig().ZeroHash, 0, 0))
+	require.NoError(t, c.cfg.ForkChoiceStore.InsertOptimisticBlock(ctx, 103, [32]byte{'d'}, [32]byte{}, params.BeaconConfig().ZeroHash, 0, 0))
+	require.NoError(t, c.cfg.ForkChoiceStore.InsertOptimisticBlock(ctx, 104, [32]byte{'e'}, [32]byte{'b'}, params.BeaconConfig().ZeroHash, 0, 0))
 
 	roots, slots := c.ChainHeads()
 	require.DeepEqual(t, [][32]byte{{'c'}, {'d'}, {'e'}}, roots)
 	require.DeepEqual(t, []types.Slot{102, 103, 104}, slots)
 }
 
+func TestService_ChainHeads_DoublyLinkedTree(t *testing.T) {
+	ctx := context.Background()
+	c := &Service{cfg: &config{ForkChoiceStore: doublylinkedtree.New(0, 0)}}
+	require.NoError(t, c.cfg.ForkChoiceStore.InsertOptimisticBlock(ctx, 100, [32]byte{'a'}, [32]byte{}, params.BeaconConfig().ZeroHash, 0, 0))
+	require.NoError(t, c.cfg.ForkChoiceStore.InsertOptimisticBlock(ctx, 101, [32]byte{'b'}, [32]byte{'a'}, params.BeaconConfig().ZeroHash, 0, 0))
+	require.NoError(t, c.cfg.ForkChoiceStore.InsertOptimisticBlock(ctx, 102, [32]byte{'c'}, [32]byte{'b'}, params.BeaconConfig().ZeroHash, 0, 0))
+	require.NoError(t, c.cfg.ForkChoiceStore.InsertOptimisticBlock(ctx, 103, [32]byte{'d'}, [32]byte{}, params.BeaconConfig().ZeroHash, 0, 0))
+	require.NoError(t, c.cfg.ForkChoiceStore.InsertOptimisticBlock(ctx, 104, [32]byte{'e'}, [32]byte{'b'}, params.BeaconConfig().ZeroHash, 0, 0))
+
+	roots, slots := c.ChainHeads()
+	require.Equal(t, 3, len(roots))
+	rootMap := map[[32]byte]types.Slot{[32]byte{'c'}: 102, [32]byte{'d'}: 103, [32]byte{'e'}: 104}
+	for i, root := range roots {
+		slot, ok := rootMap[root]
+		require.Equal(t, true, ok)
+		require.Equal(t, slot, slots[i])
+	}
+}
+
 func TestService_HeadPublicKeyToValidatorIndex(t *testing.T) {
 	s, _ := util.DeterministicGenesisState(t, 10)
 	c := &Service{}
@@ -356,7 +382,7 @@ func TestService_HeadValidatorIndexToPublicKeyNil(t *testing.T) {
 	require.Equal(t, [fieldparams.BLSPubkeyLength]byte{}, p)
 }
 
-func TestService_IsOptimistic(t *testing.T) {
+func TestService_IsOptimistic_ProtoArray(t *testing.T) {
 	params.SetupTestConfigCleanup(t)
 	cfg := params.BeaconConfig()
 	cfg.BellatrixForkEpoch = 0
@@ -364,8 +390,24 @@ func TestService_IsOptimistic(t *testing.T) {
 
 	ctx := context.Background()
 	c := &Service{cfg: &config{ForkChoiceStore: protoarray.New(0, 0, [32]byte{})}, head: &head{slot: 101, root: [32]byte{'b'}}}
-	require.NoError(t, c.cfg.ForkChoiceStore.ProcessBlock(ctx, 100, [32]byte{'a'}, [32]byte{}, [32]byte{}, 0, 0))
-	require.NoError(t, c.cfg.ForkChoiceStore.ProcessBlock(ctx, 101, [32]byte{'b'}, [32]byte{'a'}, [32]byte{}, 0, 0))
+	require.NoError(t, c.cfg.ForkChoiceStore.InsertOptimisticBlock(ctx, 100, [32]byte{'a'}, [32]byte{}, params.BeaconConfig().ZeroHash, 0, 0))
+	require.NoError(t, c.cfg.ForkChoiceStore.InsertOptimisticBlock(ctx, 101, [32]byte{'b'}, [32]byte{'a'}, params.BeaconConfig().ZeroHash, 0, 0))
+
+	opt, err := c.IsOptimistic(ctx)
+	require.NoError(t, err)
+	require.Equal(t, true, opt)
+}
+
+func TestService_IsOptimistic_DoublyLinkedTree(t *testing.T) {
+	params.SetupTestConfigCleanup(t)
+	cfg := params.BeaconConfig()
+	cfg.BellatrixForkEpoch = 0
+	params.OverrideBeaconConfig(cfg)
+
+	ctx := context.Background()
+	c := &Service{cfg: &config{ForkChoiceStore: doublylinkedtree.New(0, 0)}, head: &head{slot: 101, root: [32]byte{'b'}}}
+	require.NoError(t, c.cfg.ForkChoiceStore.InsertOptimisticBlock(ctx, 100, [32]byte{'a'}, [32]byte{}, params.BeaconConfig().ZeroHash, 0, 0))
+	require.NoError(t, c.cfg.ForkChoiceStore.InsertOptimisticBlock(ctx, 101, [32]byte{'b'}, [32]byte{'a'}, params.BeaconConfig().ZeroHash, 0, 0))
 
 	opt, err := c.IsOptimistic(ctx)
 	require.NoError(t, err)
@@ -380,13 +422,112 @@ func TestService_IsOptimisticBeforeBellatrix(t *testing.T) {
 	require.Equal(t, false, opt)
 }
 
-func TestService_IsOptimisticForRoot(t *testing.T) {
+func TestService_IsOptimisticForRoot_ProtoArray(t *testing.T) {
 	ctx := context.Background()
 	c := &Service{cfg: &config{ForkChoiceStore: protoarray.New(0, 0, [32]byte{})}, head: &head{slot: 101, root: [32]byte{'b'}}}
-	require.NoError(t, c.cfg.ForkChoiceStore.ProcessBlock(ctx, 100, [32]byte{'a'}, [32]byte{}, [32]byte{}, 0, 0))
-	require.NoError(t, c.cfg.ForkChoiceStore.ProcessBlock(ctx, 101, [32]byte{'b'}, [32]byte{'a'}, [32]byte{}, 0, 0))
+	require.NoError(t, c.cfg.ForkChoiceStore.InsertOptimisticBlock(ctx, 100, [32]byte{'a'}, [32]byte{}, params.BeaconConfig().ZeroHash, 0, 0))
+	require.NoError(t, c.cfg.ForkChoiceStore.InsertOptimisticBlock(ctx, 101, [32]byte{'b'}, [32]byte{'a'}, params.BeaconConfig().ZeroHash, 0, 0))
 
-	opt, err := c.IsOptimisticForRoot(ctx, [32]byte{'a'}, 100)
+	opt, err := c.IsOptimisticForRoot(ctx, [32]byte{'a'})
 	require.NoError(t, err)
 	require.Equal(t, true, opt)
 }
+
+func TestService_IsOptimisticForRoot_DoublyLinkedTree(t *testing.T) {
+	ctx := context.Background()
+	c := &Service{cfg: &config{ForkChoiceStore: doublylinkedtree.New(0, 0)}, head: &head{slot: 101, root: [32]byte{'b'}}}
+	require.NoError(t, c.cfg.ForkChoiceStore.InsertOptimisticBlock(ctx, 100, [32]byte{'a'}, [32]byte{}, params.BeaconConfig().ZeroHash, 0, 0))
+	require.NoError(t, c.cfg.ForkChoiceStore.InsertOptimisticBlock(ctx, 101, [32]byte{'b'}, [32]byte{'a'}, params.BeaconConfig().ZeroHash, 0, 0))
+
+	opt, err := c.IsOptimisticForRoot(ctx, [32]byte{'a'})
+	require.NoError(t, err)
+	require.Equal(t, true, opt)
+}
+
+func TestService_IsOptimisticForRoot_DB_ProtoArray(t *testing.T) {
+	beaconDB := testDB.SetupDB(t)
+	ctx := context.Background()
+	c := &Service{cfg: &config{BeaconDB: beaconDB, ForkChoiceStore: protoarray.New(0, 0, [32]byte{})}, head: &head{slot: 101, root: [32]byte{'b'}}}
+	c.head = &head{root: params.BeaconConfig().ZeroHash}
+	b := util.NewBeaconBlock()
+	b.Block.Slot = 10
+	br, err := b.Block.HashTreeRoot()
+	require.NoError(t, err)
+	wsb, err := wrapper.WrappedSignedBeaconBlock(b)
+	require.NoError(t, err)
+	require.NoError(t, beaconDB.SaveBlock(context.Background(), wsb))
+	require.NoError(t, beaconDB.SaveStateSummary(context.Background(), &ethpb.StateSummary{Root: br[:], Slot: 10}))
+
+	optimisticBlock := util.NewBeaconBlock()
+	optimisticBlock.Block.Slot = 11
+	optimisticRoot, err := optimisticBlock.Block.HashTreeRoot()
+	require.NoError(t, err)
+	wsb, err = wrapper.WrappedSignedBeaconBlock(optimisticBlock)
+	require.NoError(t, err)
+	require.NoError(t, beaconDB.SaveBlock(context.Background(), wsb))
+
+	validatedBlock := util.NewBeaconBlock()
+	validatedBlock.Block.Slot = 9
+	validatedRoot, err := validatedBlock.Block.HashTreeRoot()
+	require.NoError(t, err)
+	wsb, err = wrapper.WrappedSignedBeaconBlock(validatedBlock)
+	require.NoError(t, err)
+	require.NoError(t, beaconDB.SaveBlock(context.Background(), wsb))
+
+	validatedCheckpoint := &ethpb.Checkpoint{Root: br[:]}
+	require.NoError(t, beaconDB.SaveLastValidatedCheckpoint(ctx, validatedCheckpoint))
+
+	require.NoError(t, beaconDB.SaveStateSummary(context.Background(), &ethpb.StateSummary{Root: optimisticRoot[:], Slot: 11}))
+	optimistic, err := c.IsOptimisticForRoot(ctx, optimisticRoot)
+	require.NoError(t, err)
+	require.Equal(t, true, optimistic)
+
+	require.NoError(t, beaconDB.SaveStateSummary(context.Background(), &ethpb.StateSummary{Root: validatedRoot[:], Slot: 9}))
+	validated, err := c.IsOptimisticForRoot(ctx, validatedRoot)
+	require.NoError(t, err)
+	require.Equal(t, false, validated)
+}
+
+func TestService_IsOptimisticForRoot__DB_DoublyLinkedTree(t *testing.T) {
+	beaconDB := testDB.SetupDB(t)
+	ctx := context.Background()
+	c := &Service{cfg: &config{BeaconDB: beaconDB, ForkChoiceStore: doublylinkedtree.New(0, 0)}, head: &head{slot: 101, root: [32]byte{'b'}}}
+	c.head = &head{root: params.BeaconConfig().ZeroHash}
+	b := util.NewBeaconBlock()
+	b.Block.Slot = 10
+	br, err := b.Block.HashTreeRoot()
+	require.NoError(t, err)
+	wsb, err := wrapper.WrappedSignedBeaconBlock(b)
+	require.NoError(t, err)
+	require.NoError(t, beaconDB.SaveBlock(context.Background(), wsb))
+	require.NoError(t, beaconDB.SaveStateSummary(context.Background(), &ethpb.StateSummary{Root: br[:], Slot: 10}))
+
+	optimisticBlock := util.NewBeaconBlock()
+	optimisticBlock.Block.Slot = 11
+	optimisticRoot, err := optimisticBlock.Block.HashTreeRoot()
+	require.NoError(t, err)
+	wsb, err = wrapper.WrappedSignedBeaconBlock(optimisticBlock)
+	require.NoError(t, err)
+	require.NoError(t, beaconDB.SaveBlock(context.Background(), wsb))
+
+	validatedBlock := util.NewBeaconBlock()
+	validatedBlock.Block.Slot = 9
+	validatedRoot, err := validatedBlock.Block.HashTreeRoot()
+	require.NoError(t, err)
+	wsb, err = wrapper.WrappedSignedBeaconBlock(validatedBlock)
+	require.NoError(t, err)
+	require.NoError(t, beaconDB.SaveBlock(context.Background(), wsb))
+
+	validatedCheckpoint := &ethpb.Checkpoint{Root: br[:]}
+	require.NoError(t, beaconDB.SaveLastValidatedCheckpoint(ctx, validatedCheckpoint))
+
+	require.NoError(t, beaconDB.SaveStateSummary(context.Background(), &ethpb.StateSummary{Root: optimisticRoot[:], Slot: 11}))
+	optimistic, err := c.IsOptimisticForRoot(ctx, optimisticRoot)
+	require.NoError(t, err)
+	require.Equal(t, true, optimistic)
+
+	require.NoError(t, beaconDB.SaveStateSummary(context.Background(), &ethpb.StateSummary{Root: validatedRoot[:], Slot: 9}))
+	validated, err := c.IsOptimisticForRoot(ctx, validatedRoot)
+	require.NoError(t, err)
+	require.Equal(t, false, validated)
+}

beacon-chain/blockchain/checktags_test.go

@@ -1,3 +1,4 @@
+//go:build !develop
 // +build !develop
 
 package blockchain

beacon-chain/blockchain/error.go

@@ -9,4 +9,11 @@ var (
 	errNilBestJustifiedInStore = errors.New("nil best justified checkpoint returned from store")
 	// errNilFinalizedInStore is returned when a nil finalized checkpt is returned from store.
 	errNilFinalizedInStore = errors.New("nil finalized checkpoint returned from store")
+	// errInvalidNilSummary is returned when a nil summary is returned from the DB.
+	errInvalidNilSummary = errors.New("nil summary returned from the DB")
+	// errNilParentInDB is returned when a nil parent block is returned from the DB.
+	errNilParentInDB = errors.New("nil parent block in DB")
+	// errWrongBlockCound is returned when the wrong number of blocks or
+	// block roots is used
+	errWrongBlockCount = errors.New("wrong number of blocks or block roots")
 )

beacon-chain/blockchain/head.go

@@ -10,6 +10,7 @@ import (
 	"github.com/prysmaticlabs/prysm/beacon-chain/core/feed"
 	statefeed "github.com/prysmaticlabs/prysm/beacon-chain/core/feed/state"
 	"github.com/prysmaticlabs/prysm/beacon-chain/core/helpers"
+	doublylinkedtree "github.com/prysmaticlabs/prysm/beacon-chain/forkchoice/doubly-linked-tree"
 	"github.com/prysmaticlabs/prysm/beacon-chain/forkchoice/protoarray"
 	"github.com/prysmaticlabs/prysm/beacon-chain/state"
 	"github.com/prysmaticlabs/prysm/config/features"
@@ -77,7 +78,11 @@ func (s *Service) updateHead(ctx context.Context, balances []uint64) error {
 		if err != nil {
 			return err
 		}
-		s.cfg.ForkChoiceStore = protoarray.New(j.Epoch, f.Epoch, bytesutil.ToBytes32(f.Root))
+		if features.Get().EnableForkChoiceDoublyLinkedTree {
+			s.cfg.ForkChoiceStore = doublylinkedtree.New(j.Epoch, f.Epoch)
+		} else {
+			s.cfg.ForkChoiceStore = protoarray.New(j.Epoch, f.Epoch, bytesutil.ToBytes32(f.Root))
+		}
 		if err := s.insertBlockToForkChoiceStore(ctx, jb.Block(), headStartRoot, f, j); err != nil {
 			return err
 		}
@@ -143,16 +148,21 @@ func (s *Service) saveHead(ctx context.Context, headRoot [32]byte) error {
 			"oldSlot": fmt.Sprintf("%d", headSlot),
 		}).Debug("Chain reorg occurred")
 		absoluteSlotDifference := slots.AbsoluteValueSlotDifference(newHeadSlot, headSlot)
+		isOptimistic, err := s.IsOptimistic(ctx)
+		if err != nil {
+			return errors.Wrap(err, "could not check if node is optimistically synced")
+		}
 		s.cfg.StateNotifier.StateFeed().Send(&feed.Event{
 			Type: statefeed.Reorg,
 			Data: &ethpbv1.EventChainReorg{
-				Slot:         newHeadSlot,
-				Depth:        absoluteSlotDifference,
-				OldHeadBlock: oldHeadRoot[:],
-				NewHeadBlock: headRoot[:],
-				OldHeadState: oldStateRoot,
-				NewHeadState: newStateRoot,
-				Epoch:        slots.ToEpoch(newHeadSlot),
+				Slot:                newHeadSlot,
+				Depth:               absoluteSlotDifference,
+				OldHeadBlock:        oldHeadRoot[:],
+				NewHeadBlock:        headRoot[:],
+				OldHeadState:        oldStateRoot,
+				NewHeadState:        newStateRoot,
+				Epoch:               slots.ToEpoch(newHeadSlot),
+				ExecutionOptimistic: isOptimistic,
 			},
 		})
 
@@ -174,7 +184,7 @@ func (s *Service) saveHead(ctx context.Context, headRoot [32]byte) error {
 	// Forward an event capturing a new chain head over a common event feed
 	// done in a goroutine to avoid blocking the critical runtime main routine.
 	go func() {
-		if err := s.notifyNewHeadEvent(newHeadSlot, newHeadState, newStateRoot, headRoot[:]); err != nil {
+		if err := s.notifyNewHeadEvent(ctx, newHeadSlot, newHeadState, newStateRoot, headRoot[:]); err != nil {
 			log.WithError(err).Error("Could not notify event feed of new chain head")
 		}
 	}()
@@ -294,6 +304,7 @@ func (s *Service) hasHeadState() bool {
 // Notifies a common event feed of a new chain head event. Called right after a new
 // chain head is determined, set, and saved to disk.
 func (s *Service) notifyNewHeadEvent(
+	ctx context.Context,
 	newHeadSlot types.Slot,
 	newHeadState state.BeaconState,
 	newHeadStateRoot,
@@ -327,6 +338,10 @@ func (s *Service) notifyNewHeadEvent(
 			return errors.Wrap(err, "could not get duty dependent root")
 		}
 	}
+	isOptimistic, err := s.IsOptimistic(ctx)
+	if err != nil {
+		return errors.Wrap(err, "could not check if node is optimistically synced")
+	}
 	s.cfg.StateNotifier.StateFeed().Send(&feed.Event{
 		Type: statefeed.NewHead,
 		Data: &ethpbv1.EventHead{
@@ -336,6 +351,7 @@ func (s *Service) notifyNewHeadEvent(
 			EpochTransition:           slots.IsEpochStart(newHeadSlot),
 			PreviousDutyDependentRoot: previousDutyDependentRoot,
 			CurrentDutyDependentRoot:  currentDutyDependentRoot,
+			ExecutionOptimistic:       isOptimistic,
 		},
 	})
 	return nil

beacon-chain/blockchain/head_test.go

@@ -39,9 +39,10 @@ func TestSaveHead_Different(t *testing.T) {
 	service := setupBeaconChain(t, beaconDB)
 
 	util.NewBeaconBlock()
-	oldBlock := wrapper.WrappedPhase0SignedBeaconBlock(
+	oldBlock, err := wrapper.WrappedSignedBeaconBlock(
 		util.NewBeaconBlock(),
 	)
+	require.NoError(t, err)
 	require.NoError(t, service.cfg.BeaconDB.SaveBlock(context.Background(), oldBlock))
 	oldRoot, err := oldBlock.Block().HashTreeRoot()
 	require.NoError(t, err)
@@ -55,7 +56,9 @@ func TestSaveHead_Different(t *testing.T) {
 	newHeadSignedBlock.Block.Slot = 1
 	newHeadBlock := newHeadSignedBlock.Block
 
-	require.NoError(t, service.cfg.BeaconDB.SaveBlock(context.Background(), wrapper.WrappedPhase0SignedBeaconBlock(newHeadSignedBlock)))
+	wsb, err := wrapper.WrappedSignedBeaconBlock(newHeadSignedBlock)
+	require.NoError(t, err)
+	require.NoError(t, service.cfg.BeaconDB.SaveBlock(context.Background(), wsb))
 	newRoot, err := newHeadBlock.HashTreeRoot()
 	require.NoError(t, err)
 	headState, err := util.NewBeaconState()
@@ -80,9 +83,10 @@ func TestSaveHead_Different_Reorg(t *testing.T) {
 	beaconDB := testDB.SetupDB(t)
 	service := setupBeaconChain(t, beaconDB)
 
-	oldBlock := wrapper.WrappedPhase0SignedBeaconBlock(
+	oldBlock, err := wrapper.WrappedSignedBeaconBlock(
 		util.NewBeaconBlock(),
 	)
+	require.NoError(t, err)
 	require.NoError(t, service.cfg.BeaconDB.SaveBlock(context.Background(), oldBlock))
 	oldRoot, err := oldBlock.Block().HashTreeRoot()
 	require.NoError(t, err)
@@ -98,7 +102,9 @@ func TestSaveHead_Different_Reorg(t *testing.T) {
 	newHeadSignedBlock.Block.ParentRoot = reorgChainParent[:]
 	newHeadBlock := newHeadSignedBlock.Block
 
-	require.NoError(t, service.cfg.BeaconDB.SaveBlock(context.Background(), wrapper.WrappedPhase0SignedBeaconBlock(newHeadSignedBlock)))
+	wsb, err := wrapper.WrappedSignedBeaconBlock(newHeadSignedBlock)
+	require.NoError(t, err)
+	require.NoError(t, service.cfg.BeaconDB.SaveBlock(context.Background(), wsb))
 	newRoot, err := newHeadBlock.HashTreeRoot()
 	require.NoError(t, err)
 	headState, err := util.NewBeaconState()
@@ -139,7 +145,9 @@ func TestUpdateHead_MissingJustifiedRoot(t *testing.T) {
 	service := setupBeaconChain(t, beaconDB)
 
 	b := util.NewBeaconBlock()
-	require.NoError(t, service.cfg.BeaconDB.SaveBlock(context.Background(), wrapper.WrappedPhase0SignedBeaconBlock(b)))
+	wsb, err := wrapper.WrappedSignedBeaconBlock(b)
+	require.NoError(t, err)
+	require.NoError(t, service.cfg.BeaconDB.SaveBlock(context.Background(), wsb))
 	r, err := b.Block.HashTreeRoot()
 	require.NoError(t, err)
 
@@ -162,7 +170,7 @@ func Test_notifyNewHeadEvent(t *testing.T) {
 		}
 		newHeadStateRoot := [32]byte{2}
 		newHeadRoot := [32]byte{3}
-		err := srv.notifyNewHeadEvent(1, bState, newHeadStateRoot[:], newHeadRoot[:])
+		err := srv.notifyNewHeadEvent(context.Background(), 1, bState, newHeadStateRoot[:], newHeadRoot[:])
 		require.NoError(t, err)
 		events := notifier.ReceivedEvents()
 		require.Equal(t, 1, len(events))
@@ -197,7 +205,7 @@ func Test_notifyNewHeadEvent(t *testing.T) {
 
 		newHeadStateRoot := [32]byte{2}
 		newHeadRoot := [32]byte{3}
-		err = srv.notifyNewHeadEvent(epoch2Start, bState, newHeadStateRoot[:], newHeadRoot[:])
+		err = srv.notifyNewHeadEvent(context.Background(), epoch2Start, bState, newHeadStateRoot[:], newHeadRoot[:])
 		require.NoError(t, err)
 		events := notifier.ReceivedEvents()
 		require.Equal(t, 1, len(events))
@@ -233,7 +241,9 @@ func TestSaveOrphanedAtts(t *testing.T) {
 	service := setupBeaconChain(t, beaconDB)
 	service.genesisTime = time.Now()
 
-	require.NoError(t, service.cfg.BeaconDB.SaveBlock(ctx, wrapper.WrappedPhase0SignedBeaconBlock(b)))
+	wsb, err := wrapper.WrappedSignedBeaconBlock(b)
+	require.NoError(t, err)
+	require.NoError(t, service.cfg.BeaconDB.SaveBlock(ctx, wsb))
 	require.NoError(t, service.saveOrphanedAtts(ctx, r))
 
 	require.Equal(t, len(b.Block.Body.Attestations), service.cfg.AttPool.AggregatedAttestationCount())
@@ -259,7 +269,9 @@ func TestSaveOrphanedAtts_CanFilter(t *testing.T) {
 	service := setupBeaconChain(t, beaconDB)
 	service.genesisTime = time.Now().Add(time.Duration(-1*int64(params.BeaconConfig().SlotsPerEpoch+1)*int64(params.BeaconConfig().SecondsPerSlot)) * time.Second)
 
-	require.NoError(t, service.cfg.BeaconDB.SaveBlock(ctx, wrapper.WrappedPhase0SignedBeaconBlock(b)))
+	wsb, err := wrapper.WrappedSignedBeaconBlock(b)
+	require.NoError(t, err)
+	require.NoError(t, service.cfg.BeaconDB.SaveBlock(ctx, wsb))
 	require.NoError(t, service.saveOrphanedAtts(ctx, r))
 
 	require.Equal(t, 0, service.cfg.AttPool.AggregatedAttestationCount())

beacon-chain/blockchain/info.go

@@ -1,99 +0,0 @@
-package blockchain
-
-import (
-	"encoding/hex"
-	"fmt"
-	"net/http"
-
-	"github.com/emicklei/dot"
-	"github.com/prysmaticlabs/prysm/config/params"
-)
-
-const template = `<html>
-<head>
-    <script src="//cdnjs.cloudflare.com/ajax/libs/viz.js/2.1.2/viz.js"></script>
-    <script src="//cdnjs.cloudflare.com/ajax/libs/viz.js/2.1.2/full.render.js"></script>
-<body>
-    <script type="application/javascript">
-        var graph = ` + "`%s`;" + `
-        var viz = new Viz();
-        viz.renderSVGElement(graph) // reading the graph.
-            .then(function(element) {
-                document.body.appendChild(element); // appends to document.
-            })
-            .catch(error => {
-                // Create a new Viz instance (@see Caveats page for more info)
-                viz = new Viz();
-                // Possibly display the error
-                console.error(error);
-            });
-    </script>
-</head>
-</body>
-</html>`
-
-// TreeHandler is a handler to serve /tree page in metrics.
-func (s *Service) TreeHandler(w http.ResponseWriter, r *http.Request) {
-	headState, err := s.HeadState(r.Context())
-	if err != nil {
-		log.WithError(err).Error("Could not get head state")
-		return
-	}
-	if headState == nil || headState.IsNil() {
-		if _, err := w.Write([]byte("Unavailable during initial syncing")); err != nil {
-			log.WithError(err).Error("Failed to render p2p info page")
-		}
-	}
-
-	nodes := s.cfg.ForkChoiceStore.Nodes()
-
-	graph := dot.NewGraph(dot.Directed)
-	graph.Attr("rankdir", "RL")
-	graph.Attr("labeljust", "l")
-
-	dotNodes := make([]*dot.Node, len(nodes))
-	avgBalance := uint64(averageBalance(headState.Balances()))
-
-	for i := len(nodes) - 1; i >= 0; i-- {
-		// Construct label for each node.
-		slot := fmt.Sprintf("%d", nodes[i].Slot())
-		weight := fmt.Sprintf("%d", nodes[i].Weight()/1e9) // Convert unit Gwei to unit ETH.
-		votes := fmt.Sprintf("%d", nodes[i].Weight()/1e9/avgBalance)
-		index := fmt.Sprintf("%d", i)
-		g := nodes[i].Graffiti()
-		graffiti := hex.EncodeToString(g[:8])
-		label := "slot: " + slot + "\n votes: " + votes + "\n weight: " + weight + "\n graffiti: " + graffiti
-		var dotN dot.Node
-		if nodes[i].Parent() != ^uint64(0) {
-			dotN = graph.Node(index).Box().Attr("label", label)
-		}
-
-		if nodes[i].Slot() == s.HeadSlot() &&
-			nodes[i].BestDescendant() == ^uint64(0) &&
-			nodes[i].Parent() != ^uint64(0) {
-			dotN = dotN.Attr("color", "green")
-		}
-
-		dotNodes[i] = &dotN
-	}
-
-	for i := len(nodes) - 1; i >= 0; i-- {
-		if nodes[i].Parent() != ^uint64(0) && nodes[i].Parent() < uint64(len(dotNodes)) {
-			graph.Edge(*dotNodes[i], *dotNodes[nodes[i].Parent()])
-		}
-	}
-
-	w.WriteHeader(http.StatusOK)
-	w.Header().Set("Content-Type", "text/html")
-	if _, err := fmt.Fprintf(w, template, graph.String()); err != nil {
-		log.WithError(err).Error("Failed to render p2p info page")
-	}
-}
-
-func averageBalance(balances []uint64) float64 {
-	total := uint64(0)
-	for i := 0; i < len(balances); i++ {
-		total += balances[i]
-	}
-	return float64(total) / float64(len(balances)) / float64(params.BeaconConfig().GweiPerEth)
-}

beacon-chain/blockchain/info_test.go

@@ -1,50 +0,0 @@
-package blockchain
-
-import (
-	"context"
-	"net/http"
-	"net/http/httptest"
-	"testing"
-
-	testDB "github.com/prysmaticlabs/prysm/beacon-chain/db/testing"
-	"github.com/prysmaticlabs/prysm/beacon-chain/forkchoice/protoarray"
-	"github.com/prysmaticlabs/prysm/beacon-chain/state/stategen"
-	"github.com/prysmaticlabs/prysm/config/params"
-	"github.com/prysmaticlabs/prysm/proto/prysm/v1alpha1/wrapper"
-	"github.com/prysmaticlabs/prysm/testing/assert"
-	"github.com/prysmaticlabs/prysm/testing/require"
-	"github.com/prysmaticlabs/prysm/testing/util"
-)
-
-func TestService_TreeHandler(t *testing.T) {
-	req, err := http.NewRequest("GET", "/tree", nil)
-	require.NoError(t, err)
-
-	ctx := context.Background()
-	beaconDB := testDB.SetupDB(t)
-	headState, err := util.NewBeaconState()
-	require.NoError(t, err)
-	require.NoError(t, headState.SetBalances([]uint64{params.BeaconConfig().GweiPerEth}))
-	fcs := protoarray.New(
-		0, // justifiedEpoch
-		0, // finalizedEpoch
-		[32]byte{'a'},
-	)
-	opts := []Option{
-		WithDatabase(beaconDB),
-		WithStateGen(stategen.New(beaconDB)),
-		WithForkChoiceStore(fcs),
-	}
-	s, err := NewService(ctx, opts...)
-	require.NoError(t, err)
-	require.NoError(t, s.cfg.ForkChoiceStore.ProcessBlock(ctx, 0, [32]byte{'a'}, [32]byte{'g'}, [32]byte{'c'}, 0, 0))
-	require.NoError(t, s.cfg.ForkChoiceStore.ProcessBlock(ctx, 1, [32]byte{'b'}, [32]byte{'a'}, [32]byte{'c'}, 0, 0))
-	s.setHead([32]byte{'a'}, wrapper.WrappedPhase0SignedBeaconBlock(util.NewBeaconBlock()), headState)
-
-	rr := httptest.NewRecorder()
-	handler := http.HandlerFunc(s.TreeHandler)
-
-	handler.ServeHTTP(rr, req)
-
-	assert.Equal(t, http.StatusOK, rr.Code)
-}

beacon-chain/blockchain/log.go

@@ -6,6 +6,7 @@ import (
 	"time"
 
 	"github.com/prysmaticlabs/prysm/config/params"
+	"github.com/prysmaticlabs/prysm/encoding/bytesutil"
 	ethpb "github.com/prysmaticlabs/prysm/proto/prysm/v1alpha1"
 	"github.com/prysmaticlabs/prysm/proto/prysm/v1alpha1/block"
 	"github.com/prysmaticlabs/prysm/runtime/version"
@@ -17,7 +18,7 @@ import (
 var log = logrus.WithField("prefix", "blockchain")
 
 // logs state transition related data every slot.
-func logStateTransitionData(b block.BeaconBlock) {
+func logStateTransitionData(b block.BeaconBlock) error {
 	log := log.WithField("slot", b.Slot())
 	if len(b.Body().Attestations()) > 0 {
 		log = log.WithField("attestations", len(b.Body().Attestations()))
@@ -34,13 +35,23 @@ func logStateTransitionData(b block.BeaconBlock) {
 	if len(b.Body().VoluntaryExits()) > 0 {
 		log = log.WithField("voluntaryExits", len(b.Body().VoluntaryExits()))
 	}
-	if b.Version() == version.Altair {
+	if b.Version() == version.Altair || b.Version() == version.Bellatrix {
 		agg, err := b.Body().SyncAggregate()
-		if err == nil {
-			log = log.WithField("syncBitsCount", agg.SyncCommitteeBits.Count())
+		if err != nil {
+			return err
 		}
+		log = log.WithField("syncBitsCount", agg.SyncCommitteeBits.Count())
+	}
+	if b.Version() == version.Bellatrix {
+		p, err := b.Body().ExecutionPayload()
+		if err != nil {
+			return err
+		}
+		log = log.WithField("payloadHash", fmt.Sprintf("%#x", bytesutil.Trunc(p.BlockHash)))
+		log = log.WithField("txCount", len(p.Transactions))
 	}
 	log.Info("Finished applying state transition")
+	return nil
 }
 
 func logBlockSyncStatus(block block.BeaconBlock, blockRoot [32]byte, finalized *ethpb.Checkpoint, receivedTime time.Time, genesisTime uint64) error {

beacon-chain/blockchain/log_test.go

@@ -3,6 +3,7 @@ package blockchain
 import (
 	"testing"
 
+	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"
@@ -11,6 +12,17 @@ import (
 )
 
 func Test_logStateTransitionData(t *testing.T) {
+	payloadBlk := &ethpb.BeaconBlockBellatrix{
+		Body: &ethpb.BeaconBlockBodyBellatrix{
+			SyncAggregate: &ethpb.SyncAggregate{},
+			ExecutionPayload: &enginev1.ExecutionPayload{
+				BlockHash:    []byte{1, 2, 3},
+				Transactions: [][]byte{{}, {}},
+			},
+		},
+	}
+	wrappedPayloadBlk, err := wrapper.WrappedBeaconBlock(payloadBlk)
+	require.NoError(t, err)
 	tests := []struct {
 		name string
 		b    block.BeaconBlock
@@ -55,11 +67,15 @@ func Test_logStateTransitionData(t *testing.T) {
 				VoluntaryExits:    []*ethpb.SignedVoluntaryExit{{}}}}),
 			want: "\"Finished applying state transition\" attestations=1 attesterSlashings=1 deposits=1 prefix=blockchain proposerSlashings=1 slot=0 voluntaryExits=1",
 		},
+		{name: "has payload",
+			b:    wrappedPayloadBlk,
+			want: "\"Finished applying state transition\" payloadHash=0x010203 prefix=blockchain slot=0 syncBitsCount=0 txCount=2",
+		},
 	}
 	for _, tt := range tests {
 		hook := logTest.NewGlobal()
 		t.Run(tt.name, func(t *testing.T) {
-			logStateTransitionData(tt.b)
+			require.NoError(t, logStateTransitionData(tt.b))
 			require.LogsContain(t, hook, tt.want)
 		})
 	}

beacon-chain/blockchain/new_slot_test.go

@@ -25,11 +25,11 @@ func TestService_newSlot(t *testing.T) {
 	}
 	ctx := context.Background()
 
-	require.NoError(t, fcs.ProcessBlock(ctx, 0, [32]byte{}, [32]byte{}, [32]byte{}, 0, 0))        // genesis
-	require.NoError(t, fcs.ProcessBlock(ctx, 32, [32]byte{'a'}, [32]byte{}, [32]byte{}, 0, 0))    // finalized
-	require.NoError(t, fcs.ProcessBlock(ctx, 64, [32]byte{'b'}, [32]byte{'a'}, [32]byte{}, 0, 0)) // justified
-	require.NoError(t, fcs.ProcessBlock(ctx, 96, [32]byte{'c'}, [32]byte{'a'}, [32]byte{}, 0, 0)) // best justified
-	require.NoError(t, fcs.ProcessBlock(ctx, 97, [32]byte{'d'}, [32]byte{}, [32]byte{}, 0, 0))    // bad
+	require.NoError(t, fcs.InsertOptimisticBlock(ctx, 0, [32]byte{}, [32]byte{}, [32]byte{}, 0, 0))        // genesis
+	require.NoError(t, fcs.InsertOptimisticBlock(ctx, 32, [32]byte{'a'}, [32]byte{}, [32]byte{}, 0, 0))    // finalized
+	require.NoError(t, fcs.InsertOptimisticBlock(ctx, 64, [32]byte{'b'}, [32]byte{'a'}, [32]byte{}, 0, 0)) // justified
+	require.NoError(t, fcs.InsertOptimisticBlock(ctx, 96, [32]byte{'c'}, [32]byte{'a'}, [32]byte{}, 0, 0)) // best justified
+	require.NoError(t, fcs.InsertOptimisticBlock(ctx, 97, [32]byte{'d'}, [32]byte{}, [32]byte{}, 0, 0))    // bad
 
 	type args struct {
 		slot          types.Slot

beacon-chain/blockchain/optimistic_sync.go

@@ -5,31 +5,30 @@ import (
 	"fmt"
 
 	"github.com/pkg/errors"
-	types "github.com/prysmaticlabs/eth2-types"
 	"github.com/prysmaticlabs/prysm/beacon-chain/core/blocks"
 	"github.com/prysmaticlabs/prysm/beacon-chain/core/helpers"
 	v1 "github.com/prysmaticlabs/prysm/beacon-chain/powchain/engine-api-client/v1"
-	"github.com/prysmaticlabs/prysm/beacon-chain/state"
 	"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/runtime/version"
 	"github.com/sirupsen/logrus"
+	"go.opencensus.io/trace"
 )
 
 // 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.
-func (s *Service) notifyForkchoiceUpdate(ctx context.Context, headBlk block.BeaconBlock, finalizedRoot [32]byte) (*enginev1.PayloadIDBytes, error) {
+func (s *Service) notifyForkchoiceUpdate(ctx context.Context, headBlk block.BeaconBlock, headRoot [32]byte, finalizedRoot [32]byte) (*enginev1.PayloadIDBytes, error) {
+	ctx, span := trace.StartSpan(ctx, "blockChain.notifyForkchoiceUpdate")
+	defer span.End()
+
 	if headBlk == nil || headBlk.IsNil() || headBlk.Body().IsNil() {
 		return nil, errors.New("nil head block")
 	}
 	// Must not call fork choice updated until the transition conditions are met on the Pow network.
-	if isPreBellatrix(headBlk.Version()) {
-		return nil, nil
-	}
-	isExecutionBlk, err := blocks.ExecutionBlock(headBlk.Body())
+	isExecutionBlk, err := blocks.IsExecutionBlock(headBlk.Body())
 	if err != nil {
 		return nil, errors.Wrap(err, "could not determine if block is execution block")
 	}
@@ -45,7 +44,7 @@ func (s *Service) notifyForkchoiceUpdate(ctx context.Context, headBlk block.Beac
 		return nil, errors.Wrap(err, "could not get finalized block")
 	}
 	var finalizedHash []byte
-	if isPreBellatrix(finalizedBlock.Block().Version()) {
+	if blocks.IsPreBellatrixVersion(finalizedBlock.Block().Version()) {
 		finalizedHash = params.BeaconConfig().ZeroHash[:]
 	} else {
 		payload, err := finalizedBlock.Block().Body().ExecutionPayload()
@@ -76,28 +75,33 @@ func (s *Service) notifyForkchoiceUpdate(ctx context.Context, headBlk block.Beac
 			return nil, errors.Wrap(err, "could not notify forkchoice update from execution engine")
 		}
 	}
+	if err := s.cfg.ForkChoiceStore.SetOptimisticToValid(ctx, headRoot); err != nil {
+		return nil, errors.Wrap(err, "could not set block to valid")
+	}
 	return payloadID, nil
 }
 
 // notifyForkchoiceUpdate signals execution engine on a new payload
-func (s *Service) notifyNewPayload(ctx context.Context, preState, postState state.BeaconState, blk block.SignedBeaconBlock) error {
-	if preState == nil || postState == nil {
-		return errors.New("pre and post states must not be nil")
-	}
-	// Execution payload is only supported in Bellatrix and beyond.
-	if isPreBellatrix(postState.Version()) {
-		return nil
+func (s *Service) notifyNewPayload(ctx context.Context, preStateVersion, postStateVersion int,
+	preStateHeader, postStateHeader *ethpb.ExecutionPayloadHeader, blk block.SignedBeaconBlock, root [32]byte) error {
+	ctx, span := trace.StartSpan(ctx, "blockChain.notifyNewPayload")
+	defer span.End()
+
+	// Execution payload is only supported in Bellatrix and beyond. Pre
+	// merge blocks are never optimistic
+	if blocks.IsPreBellatrixVersion(postStateVersion) {
+		return s.cfg.ForkChoiceStore.SetOptimisticToValid(ctx, root)
 	}
 	if err := helpers.BeaconBlockIsNil(blk); err != nil {
 		return err
 	}
 	body := blk.Block().Body()
-	enabled, err := blocks.ExecutionEnabled(postState, blk.Block().Body())
+	enabled, err := blocks.IsExecutionEnabledUsingHeader(postStateHeader, body)
 	if err != nil {
 		return errors.Wrap(err, "could not determine if execution is enabled")
 	}
 	if !enabled {
-		return nil
+		return s.cfg.ForkChoiceStore.SetOptimisticToValid(ctx, root)
 	}
 	payload, err := body.ExecutionPayload()
 	if err != nil {
@@ -108,7 +112,7 @@ func (s *Service) notifyNewPayload(ctx context.Context, preState, postState stat
 		switch err {
 		case v1.ErrAcceptedSyncingPayloadStatus:
 			log.WithFields(logrus.Fields{
-				"slot":      postState.Slot(),
+				"slot":      blk.Block().Slot(),
 				"blockHash": fmt.Sprintf("%#x", bytesutil.Trunc(payload.BlockHash)),
 			}).Info("Called new payload with optimistic block")
 			return nil
@@ -117,11 +121,17 @@ func (s *Service) notifyNewPayload(ctx context.Context, preState, postState stat
 		}
 	}
 
-	// During the transition event, the transition block should be verified for sanity.
-	if isPreBellatrix(preState.Version()) {
-		return nil
+	if err := s.cfg.ForkChoiceStore.SetOptimisticToValid(ctx, root); err != nil {
+		return errors.Wrap(err, "could not set optimistic status")
 	}
-	atTransition, err := blocks.MergeTransitionBlock(preState, body)
+
+	// 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 s.validateMergeBlock(ctx, blk)
+	}
+	atTransition, err := blocks.IsMergeTransitionBlockUsingPreStatePayloadHeader(preStateHeader, body)
 	if err != nil {
 		return errors.Wrap(err, "could not check if merge block is terminal")
 	}
@@ -131,23 +141,42 @@ func (s *Service) notifyNewPayload(ctx context.Context, preState, postState stat
 	return s.validateMergeBlock(ctx, blk)
 }
 
-// isPreBellatrix returns true if input version is before bellatrix fork.
-func isPreBellatrix(v int) bool {
-	return v == version.Phase0 || v == version.Altair
-}
-
 // optimisticCandidateBlock returns true if this block can be optimistically synced.
 //
 // Spec pseudocode definition:
 // def is_optimistic_candidate_block(opt_store: OptimisticStore, current_slot: Slot, block: BeaconBlock) -> bool:
-//     justified_root = opt_store.block_states[opt_store.head_block_root].current_justified_checkpoint.root
-//     justified_is_execution_block = is_execution_block(opt_store.blocks[justified_root])
-//     block_is_deep = block.slot + SAFE_SLOTS_TO_IMPORT_OPTIMISTICALLY <= current_slot
-//     return justified_is_execution_block or block_is_deep
+//    if is_execution_block(opt_store.blocks[block.parent_root]):
+//        return True
+//
+//    justified_root = opt_store.block_states[opt_store.head_block_root].current_justified_checkpoint.root
+//    if is_execution_block(opt_store.blocks[justified_root]):
+//        return True
+//
+//    if block.slot + SAFE_SLOTS_TO_IMPORT_OPTIMISTICALLY <= current_slot:
+//        return True
+//
+//    return False
 func (s *Service) optimisticCandidateBlock(ctx context.Context, blk block.BeaconBlock) (bool, error) {
 	if blk.Slot()+params.BeaconConfig().SafeSlotsToImportOptimistically <= s.CurrentSlot() {
 		return true, nil
 	}
+
+	parent, err := s.cfg.BeaconDB.Block(ctx, bytesutil.ToBytes32(blk.ParentRoot()))
+	if err != nil {
+		return false, err
+	}
+	if parent == nil {
+		return false, errNilParentInDB
+	}
+
+	parentIsExecutionBlock, err := blocks.IsExecutionBlock(parent.Block().Body())
+	if err != nil {
+		return false, err
+	}
+	if parentIsExecutionBlock {
+		return true, nil
+	}
+
 	j := s.store.JustifiedCheckpt()
 	if j == nil {
 		return false, errNilJustifiedInStore
@@ -156,23 +185,5 @@ func (s *Service) optimisticCandidateBlock(ctx context.Context, blk block.Beacon
 	if err != nil {
 		return false, err
 	}
-	return blocks.ExecutionBlock(jBlock.Block().Body())
-}
-
-// loadSyncedTips loads a previously saved synced Tips from DB
-// if no synced tips are saved, then it creates one from the given
-// root and slot number.
-func (s *Service) loadSyncedTips(root [32]byte, slot types.Slot) error {
-	// Initialize synced tips
-	tips, err := s.cfg.BeaconDB.ValidatedTips(s.ctx)
-	if err != nil || len(tips) == 0 {
-		tips[root] = slot
-		if err != nil {
-			log.WithError(err).Warn("Could not read synced tips from DB, using finalized checkpoint as synced tip")
-		}
-	}
-	if err := s.cfg.ForkChoiceStore.SetSyncedTips(tips); err != nil {
-		return errors.Wrap(err, "could not set synced tips")
-	}
-	return nil
+	return blocks.IsExecutionBlock(jBlock.Block().Body())
 }

beacon-chain/blockchain/optimistic_sync_test.go

@@ -5,6 +5,7 @@ import (
 	"testing"
 	"time"
 
+	"github.com/prysmaticlabs/prysm/beacon-chain/core/blocks"
 	testDB "github.com/prysmaticlabs/prysm/beacon-chain/db/testing"
 	"github.com/prysmaticlabs/prysm/beacon-chain/forkchoice/protoarray"
 	engine "github.com/prysmaticlabs/prysm/beacon-chain/powchain/engine-api-client/v1"
@@ -17,6 +18,8 @@ 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"
 	"github.com/prysmaticlabs/prysm/time/slots"
@@ -35,7 +38,6 @@ func Test_NotifyForkchoiceUpdate(t *testing.T) {
 	require.NoError(t, err)
 	require.NoError(t, beaconDB.SaveBlock(ctx, altairBlk))
 	require.NoError(t, beaconDB.SaveBlock(ctx, bellatrixBlk))
-
 	fcs := protoarray.New(0, 0, [32]byte{'a'})
 	opts := []Option{
 		WithDatabase(beaconDB),
@@ -44,6 +46,7 @@ func Test_NotifyForkchoiceUpdate(t *testing.T) {
 	}
 	service, err := NewService(ctx, opts...)
 	require.NoError(t, err)
+	require.NoError(t, fcs.InsertOptimisticBlock(ctx, 0, [32]byte{}, [32]byte{}, params.BeaconConfig().ZeroHash, 0, 0))
 
 	tests := []struct {
 		name             string
@@ -154,7 +157,7 @@ func Test_NotifyForkchoiceUpdate(t *testing.T) {
 		t.Run(tt.name, func(t *testing.T) {
 			engine := &mockEngineService{forkchoiceError: tt.newForkchoiceErr}
 			service.cfg.ExecutionEngineCaller = engine
-			_, err := service.notifyForkchoiceUpdate(ctx, tt.blk, tt.finalizedRoot)
+			_, err := service.notifyForkchoiceUpdate(ctx, tt.blk, service.headRoot(), tt.finalizedRoot)
 			if tt.errString != "" {
 				require.ErrorContains(t, tt.errString, err)
 			} else {
@@ -187,6 +190,13 @@ func Test_NotifyNewPayload(t *testing.T) {
 			},
 		},
 	}
+	a := &ethpb.SignedBeaconBlockAltair{
+		Block: &ethpb.BeaconBlockAltair{
+			Body: &ethpb.BeaconBlockBodyAltair{},
+		},
+	}
+	altairBlk, err := wrapper.WrappedSignedBeaconBlock(a)
+	require.NoError(t, err)
 	bellatrixBlk, err := wrapper.WrappedSignedBeaconBlock(blk)
 	require.NoError(t, err)
 	service, err := NewService(ctx, opts...)
@@ -210,10 +220,6 @@ func Test_NotifyNewPayload(t *testing.T) {
 			postState: altairState,
 			preState:  altairState,
 		},
-		{
-			name:      "nil states",
-			errString: "pre and post states must not be nil",
-		},
 		{
 			name:      "nil beacon block",
 			postState: bellatrixState,
@@ -236,10 +242,29 @@ func Test_NotifyNewPayload(t *testing.T) {
 			errString:     "could not validate execution payload from execution engine: payload status is INVALID",
 		},
 		{
-			name:      "altair pre state",
+			name:      "altair pre state, altair block",
 			postState: bellatrixState,
 			preState:  altairState,
-			blk:       bellatrixBlk,
+			blk:       altairBlk,
+		},
+		{
+			name:      "altair pre state, happy case",
+			postState: bellatrixState,
+			preState:  altairState,
+			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
+			}(),
 		},
 		{
 			name:      "could not get merge block",
@@ -302,25 +327,85 @@ func Test_NotifyNewPayload(t *testing.T) {
 		},
 	}
 	for _, tt := range tests {
-		engine := &mockEngineService{newPayloadError: tt.newPayloadErr, blks: map[[32]byte]*v1.ExecutionBlock{}}
-		engine.blks[[32]byte{'a'}] = &v1.ExecutionBlock{
-			ParentHash:      bytesutil.PadTo([]byte{'b'}, fieldparams.RootLength),
-			TotalDifficulty: "0x2",
-		}
-		engine.blks[[32]byte{'b'}] = &v1.ExecutionBlock{
-			ParentHash:      bytesutil.PadTo([]byte{'3'}, fieldparams.RootLength),
-			TotalDifficulty: "0x1",
-		}
-		service.cfg.ExecutionEngineCaller = engine
-		err := service.notifyNewPayload(ctx, tt.preState, tt.postState, tt.blk)
-		if tt.errString != "" {
-			require.ErrorContains(t, tt.errString, err)
-		} else {
+		t.Run(tt.name, func(t *testing.T) {
+			engine := &mockEngineService{newPayloadError: tt.newPayloadErr, blks: map[[32]byte]*v1.ExecutionBlock{}}
+			engine.blks[[32]byte{'a'}] = &v1.ExecutionBlock{
+				ParentHash:      bytesutil.PadTo([]byte{'b'}, fieldparams.RootLength),
+				TotalDifficulty: "0x2",
+			}
+			engine.blks[[32]byte{'b'}] = &v1.ExecutionBlock{
+				ParentHash:      bytesutil.PadTo([]byte{'3'}, fieldparams.RootLength),
+				TotalDifficulty: "0x1",
+			}
+			service.cfg.ExecutionEngineCaller = engine
+			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)
-		}
+			err = service.notifyNewPayload(ctx, tt.preState.Version(), postVersion, payload, postHeader, tt.blk, root)
+			if tt.errString != "" {
+				require.ErrorContains(t, tt.errString, err)
+			} else {
+				require.NoError(t, err)
+			}
+		})
 	}
 }
 
+func Test_NotifyNewPayload_SetOptimisticToValid(t *testing.T) {
+	cfg := params.BeaconConfig()
+	cfg.TerminalTotalDifficulty = "2"
+	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),
+	}
+	bellatrixState, _ := util.DeterministicGenesisStateBellatrix(t, 2)
+	blk := &ethpb.SignedBeaconBlockBellatrix{
+		Block: &ethpb.BeaconBlockBellatrix{
+			Body: &ethpb.BeaconBlockBodyBellatrix{
+				ExecutionPayload: &v1.ExecutionPayload{
+					ParentHash: bytesutil.PadTo([]byte{'a'}, fieldparams.RootLength),
+				},
+			},
+		},
+	}
+	bellatrixBlk, err := wrapper.WrappedSignedBeaconBlock(blk)
+	require.NoError(t, err)
+	service, err := NewService(ctx, opts...)
+	require.NoError(t, err)
+	engine := &mockEngineService{blks: map[[32]byte]*v1.ExecutionBlock{}}
+	engine.blks[[32]byte{'a'}] = &v1.ExecutionBlock{
+		ParentHash:      bytesutil.PadTo([]byte{'b'}, fieldparams.RootLength),
+		TotalDifficulty: "0x2",
+	}
+	engine.blks[[32]byte{'b'}] = &v1.ExecutionBlock{
+		ParentHash:      bytesutil.PadTo([]byte{'3'}, fieldparams.RootLength),
+		TotalDifficulty: "0x1",
+	}
+	service.cfg.ExecutionEngineCaller = engine
+	payload, err := bellatrixState.LatestExecutionPayloadHeader()
+	require.NoError(t, err)
+	root := [32]byte{'c'}
+	require.NoError(t, service.cfg.ForkChoiceStore.InsertOptimisticBlock(ctx, 1, root, [32]byte{'a'}, params.BeaconConfig().ZeroHash, 0, 0))
+	postVersion, postHeader, err := getStateVersionAndPayload(bellatrixState)
+	require.NoError(t, err)
+	err = service.notifyNewPayload(ctx, bellatrixState.Version(), postVersion, payload, postHeader, bellatrixBlk, root)
+	require.NoError(t, err)
+	optimistic, err := service.IsOptimisticForRoot(ctx, root)
+	require.NoError(t, err)
+	require.Equal(t, false, optimistic)
+}
+
 func Test_IsOptimisticCandidateBlock(t *testing.T) {
 	params.SetupTestConfigCleanup(t)
 	params.OverrideBeaconConfig(params.MainnetConfig())
@@ -340,6 +425,12 @@ func Test_IsOptimisticCandidateBlock(t *testing.T) {
 	params.BeaconConfig().SafeSlotsToImportOptimistically = 128
 	service.genesisTime = time.Now().Add(-time.Second * 12 * 2 * 128)
 
+	parentBlk := util.NewBeaconBlockBellatrix()
+	wrappedParentBlock, err := wrapper.WrappedSignedBeaconBlock(parentBlk)
+	require.NoError(t, err)
+	parentRoot, err := wrappedParentBlock.Block().HashTreeRoot()
+	require.NoError(t, err)
+
 	tests := []struct {
 		name      string
 		blk       block.BeaconBlock
@@ -351,6 +442,7 @@ func Test_IsOptimisticCandidateBlock(t *testing.T) {
 			blk: func(tt *testing.T) block.BeaconBlock {
 				blk := util.NewBeaconBlockBellatrix()
 				blk.Block.Slot = 1
+				blk.Block.ParentRoot = parentRoot[:]
 				wr, err := wrapper.WrappedBellatrixBeaconBlock(blk.Block)
 				require.NoError(tt, err)
 				return wr
@@ -358,7 +450,8 @@ func Test_IsOptimisticCandidateBlock(t *testing.T) {
 			justified: func(tt *testing.T) block.SignedBeaconBlock {
 				blk := util.NewBeaconBlockBellatrix()
 				blk.Block.Slot = 32
-				wr, err := wrapper.WrappedBellatrixSignedBeaconBlock(blk)
+				blk.Block.ParentRoot = parentRoot[:]
+				wr, err := wrapper.WrappedSignedBeaconBlock(blk)
 				require.NoError(tt, err)
 				return wr
 			}(t),
@@ -369,6 +462,7 @@ func Test_IsOptimisticCandidateBlock(t *testing.T) {
 			blk: func(tt *testing.T) block.BeaconBlock {
 				blk := util.NewBeaconBlockAltair()
 				blk.Block.Slot = 200
+				blk.Block.ParentRoot = parentRoot[:]
 				wr, err := wrapper.WrappedAltairBeaconBlock(blk.Block)
 				require.NoError(tt, err)
 				return wr
@@ -376,7 +470,8 @@ func Test_IsOptimisticCandidateBlock(t *testing.T) {
 			justified: func(tt *testing.T) block.SignedBeaconBlock {
 				blk := util.NewBeaconBlockAltair()
 				blk.Block.Slot = 32
-				wr, err := wrapper.WrappedAltairSignedBeaconBlock(blk)
+				blk.Block.ParentRoot = parentRoot[:]
+				wr, err := wrapper.WrappedSignedBeaconBlock(blk)
 				require.NoError(tt, err)
 				return wr
 			}(t),
@@ -387,6 +482,7 @@ func Test_IsOptimisticCandidateBlock(t *testing.T) {
 			blk: func(tt *testing.T) block.BeaconBlock {
 				blk := util.NewBeaconBlockBellatrix()
 				blk.Block.Slot = 200
+				blk.Block.ParentRoot = parentRoot[:]
 				wr, err := wrapper.WrappedBellatrixBeaconBlock(blk.Block)
 				require.NoError(tt, err)
 				return wr
@@ -394,7 +490,8 @@ func Test_IsOptimisticCandidateBlock(t *testing.T) {
 			justified: func(tt *testing.T) block.SignedBeaconBlock {
 				blk := util.NewBeaconBlockBellatrix()
 				blk.Block.Slot = 32
-				wr, err := wrapper.WrappedBellatrixSignedBeaconBlock(blk)
+				blk.Block.ParentRoot = parentRoot[:]
+				wr, err := wrapper.WrappedSignedBeaconBlock(blk)
 				require.NoError(tt, err)
 				return wr
 			}(t),
@@ -405,6 +502,7 @@ func Test_IsOptimisticCandidateBlock(t *testing.T) {
 			blk: func(tt *testing.T) block.BeaconBlock {
 				blk := util.NewBeaconBlockBellatrix()
 				blk.Block.Slot = 200
+				blk.Block.ParentRoot = parentRoot[:]
 				wr, err := wrapper.WrappedBellatrixBeaconBlock(blk.Block)
 				require.NoError(tt, err)
 				return wr
@@ -412,6 +510,7 @@ func Test_IsOptimisticCandidateBlock(t *testing.T) {
 			justified: func(tt *testing.T) block.SignedBeaconBlock {
 				blk := util.NewBeaconBlockBellatrix()
 				blk.Block.Slot = 32
+				blk.Block.ParentRoot = parentRoot[:]
 				blk.Block.Body.ExecutionPayload.ParentHash = bytesutil.PadTo([]byte{'a'}, fieldparams.RootLength)
 				blk.Block.Body.ExecutionPayload.FeeRecipient = bytesutil.PadTo([]byte{'a'}, fieldparams.FeeRecipientLength)
 				blk.Block.Body.ExecutionPayload.StateRoot = bytesutil.PadTo([]byte{'a'}, fieldparams.RootLength)
@@ -420,7 +519,7 @@ func Test_IsOptimisticCandidateBlock(t *testing.T) {
 				blk.Block.Body.ExecutionPayload.PrevRandao = bytesutil.PadTo([]byte{'a'}, fieldparams.RootLength)
 				blk.Block.Body.ExecutionPayload.BaseFeePerGas = bytesutil.PadTo([]byte{'a'}, fieldparams.RootLength)
 				blk.Block.Body.ExecutionPayload.BlockHash = bytesutil.PadTo([]byte{'a'}, fieldparams.RootLength)
-				wr, err := wrapper.WrappedBellatrixSignedBeaconBlock(blk)
+				wr, err := wrapper.WrappedSignedBeaconBlock(blk)
 				require.NoError(tt, err)
 				return wr
 			}(t),
@@ -436,8 +535,158 @@ func Test_IsOptimisticCandidateBlock(t *testing.T) {
 				Root:  jroot[:],
 				Epoch: slots.ToEpoch(tt.justified.Block().Slot()),
 			})
+		require.NoError(t, service.cfg.BeaconDB.SaveBlock(ctx, wrappedParentBlock))
+
 		candidate, err := service.optimisticCandidateBlock(ctx, tt.blk)
 		require.NoError(t, err)
 		require.Equal(t, tt.want, candidate, tt.name)
 	}
 }
+
+func Test_IsOptimisticShallowExecutionParent(t *testing.T) {
+	params.SetupTestConfigCleanup(t)
+	params.OverrideBeaconConfig(params.MainnetConfig())
+
+	ctx := context.Background()
+	beaconDB := testDB.SetupDB(t)
+	opts := []Option{
+		WithDatabase(beaconDB),
+		WithStateGen(stategen.New(beaconDB)),
+	}
+
+	service, err := NewService(ctx, opts...)
+	require.NoError(t, err)
+
+	params.BeaconConfig().SafeSlotsToImportOptimistically = 128
+	service.genesisTime = time.Now().Add(-time.Second * 12 * 2 * 128)
+	payload := &v1.ExecutionPayload{
+		ParentHash:    make([]byte, 32),
+		FeeRecipient:  make([]byte, 20),
+		StateRoot:     make([]byte, 32),
+		ReceiptsRoot:  make([]byte, 32),
+		LogsBloom:     make([]byte, 256),
+		PrevRandao:    make([]byte, 32),
+		BaseFeePerGas: bytesutil.PadTo([]byte{1, 2, 3, 4}, fieldparams.RootLength),
+		BlockHash:     make([]byte, 32),
+		BlockNumber:   100,
+	}
+	body := &ethpb.BeaconBlockBodyBellatrix{ExecutionPayload: payload}
+	block := &ethpb.BeaconBlockBellatrix{Body: body, Slot: 200}
+	rawSigned := &ethpb.SignedBeaconBlockBellatrix{Block: block}
+	blk := util.HydrateSignedBeaconBlockBellatrix(rawSigned)
+	wr, err := wrapper.WrappedSignedBeaconBlock(blk)
+	require.NoError(t, err)
+	require.NoError(t, service.cfg.BeaconDB.SaveBlock(ctx, wr))
+	blkRoot, err := wr.Block().HashTreeRoot()
+	require.NoError(t, err)
+
+	childBlock := util.NewBeaconBlockBellatrix()
+	childBlock.Block.ParentRoot = blkRoot[:]
+	// shallow block
+	childBlock.Block.Slot = 201
+	wrappedChild, err := wrapper.WrappedSignedBeaconBlock(childBlock)
+	require.NoError(t, err)
+	require.NoError(t, service.cfg.BeaconDB.SaveBlock(ctx, wrappedChild))
+	candidate, err := service.optimisticCandidateBlock(ctx, wrappedChild.Block())
+	require.NoError(t, err)
+	require.Equal(t, true, candidate)
+}
+
+func Test_UpdateLastValidatedCheckpoint(t *testing.T) {
+	params.SetupTestConfigCleanup(t)
+	params.OverrideBeaconConfig(params.MainnetConfig())
+
+	ctx := context.Background()
+	beaconDB := testDB.SetupDB(t)
+	stateGen := stategen.New(beaconDB)
+	fcs := protoarray.New(0, 0, [32]byte{})
+	opts := []Option{
+		WithDatabase(beaconDB),
+		WithStateGen(stateGen),
+		WithForkChoiceStore(fcs),
+	}
+	service, err := NewService(ctx, opts...)
+	require.NoError(t, err)
+
+	genesisStateRoot := [32]byte{}
+	genesisBlk := blocks.NewGenesisBlock(genesisStateRoot[:])
+	wr, err := wrapper.WrappedSignedBeaconBlock(genesisBlk)
+	require.NoError(t, err)
+	assert.NoError(t, beaconDB.SaveBlock(ctx, wr))
+	genesisRoot, err := genesisBlk.Block.HashTreeRoot()
+	require.NoError(t, err)
+	assert.NoError(t, beaconDB.SaveGenesisBlockRoot(ctx, genesisRoot))
+	require.NoError(t, fcs.InsertOptimisticBlock(ctx, 0, genesisRoot, params.BeaconConfig().ZeroHash,
+		params.BeaconConfig().ZeroHash, 0, 0))
+	genesisSummary := &ethpb.StateSummary{
+		Root: genesisStateRoot[:],
+		Slot: 0,
+	}
+	require.NoError(t, beaconDB.SaveStateSummary(ctx, genesisSummary))
+
+	// Get last validated checkpoint
+	origCheckpoint, err := service.cfg.BeaconDB.LastValidatedCheckpoint(ctx)
+	require.NoError(t, err)
+	require.NoError(t, beaconDB.SaveLastValidatedCheckpoint(ctx, origCheckpoint))
+
+	// Optimistic finalized checkpoint
+	blk := util.NewBeaconBlock()
+	blk.Block.Slot = 320
+	blk.Block.ParentRoot = genesisRoot[:]
+	wr, err = wrapper.WrappedSignedBeaconBlock(blk)
+	require.NoError(t, err)
+	require.NoError(t, beaconDB.SaveBlock(ctx, wr))
+	opRoot, err := blk.Block.HashTreeRoot()
+	require.NoError(t, err)
+
+	opCheckpoint := &ethpb.Checkpoint{
+		Root:  opRoot[:],
+		Epoch: 10,
+	}
+	opStateSummary := &ethpb.StateSummary{
+		Root: opRoot[:],
+		Slot: 320,
+	}
+	require.NoError(t, beaconDB.SaveStateSummary(ctx, opStateSummary))
+	require.NoError(t, fcs.InsertOptimisticBlock(ctx, 320, opRoot, genesisRoot,
+		params.BeaconConfig().ZeroHash, 10, 10))
+	assert.NoError(t, beaconDB.SaveGenesisBlockRoot(ctx, opRoot))
+	require.NoError(t, service.updateFinalized(ctx, opCheckpoint))
+	cp, err := service.cfg.BeaconDB.LastValidatedCheckpoint(ctx)
+	require.NoError(t, err)
+	require.DeepEqual(t, origCheckpoint.Root, cp.Root)
+	require.Equal(t, origCheckpoint.Epoch, cp.Epoch)
+
+	// Validated finalized checkpoint
+	blk = util.NewBeaconBlock()
+	blk.Block.Slot = 640
+	blk.Block.ParentRoot = opRoot[:]
+	wr, err = wrapper.WrappedSignedBeaconBlock(blk)
+	require.NoError(t, err)
+	require.NoError(t, beaconDB.SaveBlock(ctx, wr))
+	validRoot, err := blk.Block.HashTreeRoot()
+	require.NoError(t, err)
+
+	validCheckpoint := &ethpb.Checkpoint{
+		Root:  validRoot[:],
+		Epoch: 20,
+	}
+	validSummary := &ethpb.StateSummary{
+		Root: validRoot[:],
+		Slot: 640,
+	}
+	require.NoError(t, beaconDB.SaveStateSummary(ctx, validSummary))
+	require.NoError(t, fcs.InsertOptimisticBlock(ctx, 640, validRoot, params.BeaconConfig().ZeroHash,
+		params.BeaconConfig().ZeroHash, 20, 20))
+	require.NoError(t, fcs.SetOptimisticToValid(ctx, validRoot))
+	assert.NoError(t, beaconDB.SaveGenesisBlockRoot(ctx, validRoot))
+	require.NoError(t, service.updateFinalized(ctx, validCheckpoint))
+	cp, err = service.cfg.BeaconDB.LastValidatedCheckpoint(ctx)
+	require.NoError(t, err)
+
+	optimistic, err := service.IsOptimisticForRoot(ctx, validRoot)
+	require.NoError(t, err)
+	require.Equal(t, false, optimistic)
+	require.DeepEqual(t, validCheckpoint.Root, cp.Root)
+	require.Equal(t, validCheckpoint.Epoch, cp.Epoch)
+}

beacon-chain/blockchain/options.go

@@ -11,6 +11,7 @@ import (
 	"github.com/prysmaticlabs/prysm/beacon-chain/operations/voluntaryexits"
 	"github.com/prysmaticlabs/prysm/beacon-chain/p2p"
 	"github.com/prysmaticlabs/prysm/beacon-chain/powchain"
+	enginev1 "github.com/prysmaticlabs/prysm/beacon-chain/powchain/engine-api-client/v1"
 	"github.com/prysmaticlabs/prysm/beacon-chain/state"
 	"github.com/prysmaticlabs/prysm/beacon-chain/state/stategen"
 	ethpb "github.com/prysmaticlabs/prysm/proto/prysm/v1alpha1"
@@ -50,6 +51,14 @@ func WithChainStartFetcher(f powchain.ChainStartFetcher) Option {
 	}
 }
 
+// WithExecutionEngineCaller to call execution engine.
+func WithExecutionEngineCaller(c enginev1.Caller) Option {
+	return func(s *Service) error {
+		s.cfg.ExecutionEngineCaller = c
+		return nil
+	}
+}
+
 // WithDepositCache for deposit lifecycle after chain inclusion.
 func WithDepositCache(c *depositcache.DepositCache) Option {
 	return func(s *Service) error {

beacon-chain/blockchain/process_attestation_test.go

@@ -8,6 +8,7 @@ import (
 	types "github.com/prysmaticlabs/eth2-types"
 	"github.com/prysmaticlabs/prysm/beacon-chain/core/transition"
 	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"
 	"github.com/prysmaticlabs/prysm/beacon-chain/state/stategen"
 	fieldparams "github.com/prysmaticlabs/prysm/config/fieldparams"
@@ -21,7 +22,7 @@ import (
 	"github.com/prysmaticlabs/prysm/time/slots"
 )
 
-func TestStore_OnAttestation_ErrorConditions(t *testing.T) {
+func TestStore_OnAttestation_ErrorConditions_ProtoArray(t *testing.T) {
 	ctx := context.Background()
 	beaconDB := testDB.SetupDB(t)
 
@@ -38,13 +39,17 @@ func TestStore_OnAttestation_ErrorConditions(t *testing.T) {
 
 	BlkWithOutState := util.NewBeaconBlock()
 	BlkWithOutState.Block.Slot = 0
-	require.NoError(t, beaconDB.SaveBlock(ctx, wrapper.WrappedPhase0SignedBeaconBlock(BlkWithOutState)))
+	wsb, err := wrapper.WrappedSignedBeaconBlock(BlkWithOutState)
+	require.NoError(t, err)
+	require.NoError(t, beaconDB.SaveBlock(ctx, wsb))
 	BlkWithOutStateRoot, err := BlkWithOutState.Block.HashTreeRoot()
 	require.NoError(t, err)
 
 	BlkWithStateBadAtt := util.NewBeaconBlock()
 	BlkWithStateBadAtt.Block.Slot = 1
-	require.NoError(t, beaconDB.SaveBlock(ctx, wrapper.WrappedPhase0SignedBeaconBlock(BlkWithStateBadAtt)))
+	wsb, err = wrapper.WrappedSignedBeaconBlock(BlkWithStateBadAtt)
+	require.NoError(t, err)
+	require.NoError(t, beaconDB.SaveBlock(ctx, wsb))
 	BlkWithStateBadAttRoot, err := BlkWithStateBadAtt.Block.HashTreeRoot()
 	require.NoError(t, err)
 
@@ -55,7 +60,9 @@ func TestStore_OnAttestation_ErrorConditions(t *testing.T) {
 
 	BlkWithValidState := util.NewBeaconBlock()
 	BlkWithValidState.Block.Slot = 2
-	require.NoError(t, beaconDB.SaveBlock(ctx, wrapper.WrappedPhase0SignedBeaconBlock(BlkWithValidState)))
+	wsb, err = wrapper.WrappedSignedBeaconBlock(BlkWithValidState)
+	require.NoError(t, err)
+	require.NoError(t, beaconDB.SaveBlock(ctx, wsb))
 
 	BlkWithValidStateRoot, err := BlkWithValidState.Block.HashTreeRoot()
 	require.NoError(t, err)
@@ -127,7 +134,119 @@ func TestStore_OnAttestation_ErrorConditions(t *testing.T) {
 	}
 }
 
-func TestStore_OnAttestation_Ok(t *testing.T) {
+func TestStore_OnAttestation_ErrorConditions_DoublyLinkedTree(t *testing.T) {
+	ctx := context.Background()
+	beaconDB := testDB.SetupDB(t)
+
+	opts := []Option{
+		WithDatabase(beaconDB),
+		WithForkChoiceStore(doublylinkedtree.New(0, 0)),
+		WithStateGen(stategen.New(beaconDB)),
+	}
+	service, err := NewService(ctx, opts...)
+	require.NoError(t, err)
+
+	_, err = blockTree1(t, beaconDB, []byte{'g'})
+	require.NoError(t, err)
+
+	BlkWithOutState := util.NewBeaconBlock()
+	BlkWithOutState.Block.Slot = 0
+	wsb, err := wrapper.WrappedSignedBeaconBlock(BlkWithOutState)
+	require.NoError(t, err)
+	require.NoError(t, beaconDB.SaveBlock(ctx, wsb))
+	BlkWithOutStateRoot, err := BlkWithOutState.Block.HashTreeRoot()
+	require.NoError(t, err)
+
+	BlkWithStateBadAtt := util.NewBeaconBlock()
+	BlkWithStateBadAtt.Block.Slot = 1
+	wsb, err = wrapper.WrappedSignedBeaconBlock(BlkWithStateBadAtt)
+	require.NoError(t, err)
+	require.NoError(t, beaconDB.SaveBlock(ctx, wsb))
+	BlkWithStateBadAttRoot, err := BlkWithStateBadAtt.Block.HashTreeRoot()
+	require.NoError(t, err)
+
+	s, err := util.NewBeaconState()
+	require.NoError(t, err)
+	require.NoError(t, s.SetSlot(100*params.BeaconConfig().SlotsPerEpoch))
+	require.NoError(t, service.cfg.BeaconDB.SaveState(ctx, s, BlkWithStateBadAttRoot))
+
+	BlkWithValidState := util.NewBeaconBlock()
+	BlkWithValidState.Block.Slot = 2
+	wsb, err = wrapper.WrappedSignedBeaconBlock(BlkWithValidState)
+	require.NoError(t, err)
+	require.NoError(t, beaconDB.SaveBlock(ctx, wsb))
+
+	BlkWithValidStateRoot, err := BlkWithValidState.Block.HashTreeRoot()
+	require.NoError(t, err)
+	s, err = util.NewBeaconState()
+	require.NoError(t, err)
+	err = s.SetFork(&ethpb.Fork{
+		Epoch:           0,
+		CurrentVersion:  params.BeaconConfig().GenesisForkVersion,
+		PreviousVersion: params.BeaconConfig().GenesisForkVersion,
+	})
+	require.NoError(t, err)
+	require.NoError(t, service.cfg.BeaconDB.SaveState(ctx, s, BlkWithValidStateRoot))
+
+	tests := []struct {
+		name      string
+		a         *ethpb.Attestation
+		wantedErr string
+	}{
+		{
+			name:      "attestation's data slot not aligned with target vote",
+			a:         util.HydrateAttestation(&ethpb.Attestation{Data: &ethpb.AttestationData{Slot: params.BeaconConfig().SlotsPerEpoch, Target: &ethpb.Checkpoint{Root: make([]byte, 32)}}}),
+			wantedErr: "slot 32 does not match target epoch 0",
+		},
+		{
+			name:      "no pre state for attestations's target block",
+			a:         util.HydrateAttestation(&ethpb.Attestation{Data: &ethpb.AttestationData{Target: &ethpb.Checkpoint{Root: BlkWithOutStateRoot[:]}}}),
+			wantedErr: "could not get pre state for epoch 0",
+		},
+		{
+			name: "process attestation doesn't match current epoch",
+			a: util.HydrateAttestation(&ethpb.Attestation{Data: &ethpb.AttestationData{Slot: 100 * params.BeaconConfig().SlotsPerEpoch, Target: &ethpb.Checkpoint{Epoch: 100,
+				Root: BlkWithStateBadAttRoot[:]}}}),
+			wantedErr: "target epoch 100 does not match current epoch",
+		},
+		{
+			name:      "process nil attestation",
+			a:         nil,
+			wantedErr: "attestation can't be nil",
+		},
+		{
+			name:      "process nil field (a.Data) in attestation",
+			a:         &ethpb.Attestation{},
+			wantedErr: "attestation's data can't be nil",
+		},
+		{
+			name: "process nil field (a.Target) in attestation",
+			a: &ethpb.Attestation{
+				Data: &ethpb.AttestationData{
+					BeaconBlockRoot: make([]byte, fieldparams.RootLength),
+					Target:          nil,
+					Source:          &ethpb.Checkpoint{Root: make([]byte, fieldparams.RootLength)},
+				},
+				AggregationBits: make([]byte, 1),
+				Signature:       make([]byte, 96),
+			},
+			wantedErr: "attestation's target can't be nil",
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			err := service.OnAttestation(ctx, tt.a)
+			if tt.wantedErr != "" {
+				assert.ErrorContains(t, tt.wantedErr, err)
+			} else {
+				assert.NoError(t, err)
+			}
+		})
+	}
+}
+
+func TestStore_OnAttestation_Ok_ProtoArray(t *testing.T) {
 	ctx := context.Background()
 	beaconDB := testDB.SetupDB(t)
 
@@ -149,7 +268,33 @@ func TestStore_OnAttestation_Ok(t *testing.T) {
 	copied, err = transition.ProcessSlots(ctx, copied, 1)
 	require.NoError(t, err)
 	require.NoError(t, service.cfg.BeaconDB.SaveState(ctx, copied, tRoot))
-	require.NoError(t, service.cfg.ForkChoiceStore.ProcessBlock(ctx, 0, tRoot, tRoot, tRoot, 1, 1))
+	require.NoError(t, service.cfg.ForkChoiceStore.InsertOptimisticBlock(ctx, 0, tRoot, tRoot, params.BeaconConfig().ZeroHash, 1, 1))
+	require.NoError(t, service.OnAttestation(ctx, att[0]))
+}
+
+func TestStore_OnAttestation_Ok_DoublyLinkedTree(t *testing.T) {
+	ctx := context.Background()
+	beaconDB := testDB.SetupDB(t)
+
+	fcs := doublylinkedtree.New(0, 0)
+	opts := []Option{
+		WithDatabase(beaconDB),
+		WithStateGen(stategen.New(beaconDB)),
+		WithForkChoiceStore(fcs),
+	}
+	service, err := NewService(ctx, opts...)
+	require.NoError(t, err)
+	genesisState, pks := util.DeterministicGenesisState(t, 64)
+	service.SetGenesisTime(time.Unix(time.Now().Unix()-int64(params.BeaconConfig().SecondsPerSlot), 0))
+	require.NoError(t, service.saveGenesisData(ctx, genesisState))
+	att, err := util.GenerateAttestations(genesisState, pks, 1, 0, false)
+	require.NoError(t, err)
+	tRoot := bytesutil.ToBytes32(att[0].Data.Target.Root)
+	copied := genesisState.Copy()
+	copied, err = transition.ProcessSlots(ctx, copied, 1)
+	require.NoError(t, err)
+	require.NoError(t, service.cfg.BeaconDB.SaveState(ctx, copied, tRoot))
+	require.NoError(t, service.cfg.ForkChoiceStore.InsertOptimisticBlock(ctx, 0, tRoot, tRoot, params.BeaconConfig().ZeroHash, 1, 1))
 	require.NoError(t, service.OnAttestation(ctx, att[0]))
 }
 
@@ -305,7 +450,9 @@ func TestVerifyBeaconBlock_futureBlock(t *testing.T) {
 
 	b := util.NewBeaconBlock()
 	b.Block.Slot = 2
-	require.NoError(t, service.cfg.BeaconDB.SaveBlock(ctx, wrapper.WrappedPhase0SignedBeaconBlock(b)))
+	wsb, err := wrapper.WrappedSignedBeaconBlock(b)
+	require.NoError(t, err)
+	require.NoError(t, service.cfg.BeaconDB.SaveBlock(ctx, wsb))
 	r, err := b.Block.HashTreeRoot()
 	require.NoError(t, err)
 	d := &ethpb.AttestationData{Slot: 1, BeaconBlockRoot: r[:]}
@@ -322,7 +469,9 @@ func TestVerifyBeaconBlock_OK(t *testing.T) {
 
 	b := util.NewBeaconBlock()
 	b.Block.Slot = 2
-	require.NoError(t, service.cfg.BeaconDB.SaveBlock(ctx, wrapper.WrappedPhase0SignedBeaconBlock(b)))
+	wsb, err := wrapper.WrappedSignedBeaconBlock(b)
+	require.NoError(t, err)
+	require.NoError(t, service.cfg.BeaconDB.SaveBlock(ctx, wsb))
 	r, err := b.Block.HashTreeRoot()
 	require.NoError(t, err)
 	d := &ethpb.AttestationData{Slot: 2, BeaconBlockRoot: r[:]}
@@ -330,7 +479,7 @@ func TestVerifyBeaconBlock_OK(t *testing.T) {
 	assert.NoError(t, service.verifyBeaconBlock(ctx, d), "Did not receive the wanted error")
 }
 
-func TestVerifyFinalizedConsistency_InconsistentRoot(t *testing.T) {
+func TestVerifyFinalizedConsistency_InconsistentRoot_ProtoArray(t *testing.T) {
 	ctx := context.Background()
 	beaconDB := testDB.SetupDB(t)
 
@@ -345,7 +494,9 @@ func TestVerifyFinalizedConsistency_InconsistentRoot(t *testing.T) {
 
 	b32 := util.NewBeaconBlock()
 	b32.Block.Slot = 32
-	require.NoError(t, service.cfg.BeaconDB.SaveBlock(ctx, wrapper.WrappedPhase0SignedBeaconBlock(b32)))
+	wsb, err := wrapper.WrappedSignedBeaconBlock(b32)
+	require.NoError(t, err)
+	require.NoError(t, service.cfg.BeaconDB.SaveBlock(ctx, wsb))
 	r32, err := b32.Block.HashTreeRoot()
 	require.NoError(t, err)
 
@@ -353,7 +504,44 @@ func TestVerifyFinalizedConsistency_InconsistentRoot(t *testing.T) {
 	b33 := util.NewBeaconBlock()
 	b33.Block.Slot = 33
 	b33.Block.ParentRoot = r32[:]
-	require.NoError(t, service.cfg.BeaconDB.SaveBlock(ctx, wrapper.WrappedPhase0SignedBeaconBlock(b33)))
+	wsb, err = wrapper.WrappedSignedBeaconBlock(b33)
+	require.NoError(t, err)
+	require.NoError(t, service.cfg.BeaconDB.SaveBlock(ctx, wsb))
+	r33, err := b33.Block.HashTreeRoot()
+	require.NoError(t, err)
+
+	err = service.VerifyFinalizedConsistency(context.Background(), r33[:])
+	require.ErrorContains(t, "Root and finalized store are not consistent", err)
+}
+
+func TestVerifyFinalizedConsistency_InconsistentRoot_DoublyLinkedTree(t *testing.T) {
+	ctx := context.Background()
+	beaconDB := testDB.SetupDB(t)
+
+	fcs := doublylinkedtree.New(0, 0)
+	opts := []Option{
+		WithDatabase(beaconDB),
+		WithStateGen(stategen.New(beaconDB)),
+		WithForkChoiceStore(fcs),
+	}
+	service, err := NewService(ctx, opts...)
+	require.NoError(t, err)
+
+	b32 := util.NewBeaconBlock()
+	b32.Block.Slot = 32
+	wsb, err := wrapper.WrappedSignedBeaconBlock(b32)
+	require.NoError(t, err)
+	require.NoError(t, service.cfg.BeaconDB.SaveBlock(ctx, wsb))
+	r32, err := b32.Block.HashTreeRoot()
+	require.NoError(t, err)
+
+	service.store.SetFinalizedCheckpt(&ethpb.Checkpoint{Epoch: 1})
+	b33 := util.NewBeaconBlock()
+	b33.Block.Slot = 33
+	b33.Block.ParentRoot = r32[:]
+	wsb, err = wrapper.WrappedSignedBeaconBlock(b33)
+	require.NoError(t, err)
+	require.NoError(t, service.cfg.BeaconDB.SaveBlock(ctx, wsb))
 	r33, err := b33.Block.HashTreeRoot()
 	require.NoError(t, err)
 
@@ -370,7 +558,9 @@ func TestVerifyFinalizedConsistency_OK(t *testing.T) {
 
 	b32 := util.NewBeaconBlock()
 	b32.Block.Slot = 32
-	require.NoError(t, service.cfg.BeaconDB.SaveBlock(ctx, wrapper.WrappedPhase0SignedBeaconBlock(b32)))
+	wsb, err := wrapper.WrappedSignedBeaconBlock(b32)
+	require.NoError(t, err)
+	require.NoError(t, service.cfg.BeaconDB.SaveBlock(ctx, wsb))
 	r32, err := b32.Block.HashTreeRoot()
 	require.NoError(t, err)
 
@@ -379,7 +569,9 @@ func TestVerifyFinalizedConsistency_OK(t *testing.T) {
 	b33 := util.NewBeaconBlock()
 	b33.Block.Slot = 33
 	b33.Block.ParentRoot = r32[:]
-	require.NoError(t, service.cfg.BeaconDB.SaveBlock(ctx, wrapper.WrappedPhase0SignedBeaconBlock(b33)))
+	wsb, err = wrapper.WrappedSignedBeaconBlock(b33)
+	require.NoError(t, err)
+	require.NoError(t, service.cfg.BeaconDB.SaveBlock(ctx, wsb))
 	r33, err := b33.Block.HashTreeRoot()
 	require.NoError(t, err)
 
@@ -407,8 +599,8 @@ func TestVerifyFinalizedConsistency_IsCanonical(t *testing.T) {
 	r33, err := b33.Block.HashTreeRoot()
 	require.NoError(t, err)
 
-	require.NoError(t, service.cfg.ForkChoiceStore.ProcessBlock(ctx, b32.Block.Slot, r32, [32]byte{}, [32]byte{}, 0, 0))
-	require.NoError(t, service.cfg.ForkChoiceStore.ProcessBlock(ctx, b33.Block.Slot, r33, r32, [32]byte{}, 0, 0))
+	require.NoError(t, service.cfg.ForkChoiceStore.InsertOptimisticBlock(ctx, b32.Block.Slot, r32, [32]byte{}, params.BeaconConfig().ZeroHash, 0, 0))
+	require.NoError(t, service.cfg.ForkChoiceStore.InsertOptimisticBlock(ctx, b33.Block.Slot, r33, r32, params.BeaconConfig().ZeroHash, 0, 0))
 
 	_, err = service.cfg.ForkChoiceStore.Head(ctx, 0, r32, []uint64{}, 0)
 	require.NoError(t, err)

beacon-chain/blockchain/process_block.go

@@ -6,11 +6,13 @@ import (
 	"time"
 
 	"github.com/pkg/errors"
+	"github.com/prysmaticlabs/prysm/beacon-chain/core/blocks"
 	"github.com/prysmaticlabs/prysm/beacon-chain/core/feed"
 	statefeed "github.com/prysmaticlabs/prysm/beacon-chain/core/feed/state"
 	"github.com/prysmaticlabs/prysm/beacon-chain/core/helpers"
 	coreTime "github.com/prysmaticlabs/prysm/beacon-chain/core/time"
 	"github.com/prysmaticlabs/prysm/beacon-chain/core/transition"
+	forkchoicetypes "github.com/prysmaticlabs/prysm/beacon-chain/forkchoice/types"
 	"github.com/prysmaticlabs/prysm/beacon-chain/state"
 	"github.com/prysmaticlabs/prysm/config/features"
 	"github.com/prysmaticlabs/prysm/config/params"
@@ -21,6 +23,7 @@ import (
 	ethpb "github.com/prysmaticlabs/prysm/proto/prysm/v1alpha1"
 	"github.com/prysmaticlabs/prysm/proto/prysm/v1alpha1/attestation"
 	"github.com/prysmaticlabs/prysm/proto/prysm/v1alpha1/block"
+	"github.com/prysmaticlabs/prysm/runtime/version"
 	"github.com/prysmaticlabs/prysm/time/slots"
 	"go.opencensus.io/trace"
 )
@@ -98,20 +101,34 @@ func (s *Service) onBlock(ctx context.Context, signed block.SignedBeaconBlock, b
 		return err
 	}
 
+	preStateVersion, preStateHeader, err := getStateVersionAndPayload(preState)
+	if err != nil {
+		return err
+	}
 	postState, err := transition.ExecuteStateTransition(ctx, preState, signed)
 	if err != nil {
 		return err
 	}
+	if err := s.savePostStateInfo(ctx, blockRoot, signed, postState, false /* reg sync */); err != nil {
+		return err
+	}
+	postStateVersion, postStateHeader, err := getStateVersionAndPayload(postState)
+	if err != nil {
+		return err
+	}
+	if err := s.notifyNewPayload(ctx, preStateVersion, postStateVersion, preStateHeader, postStateHeader, signed, blockRoot); err != nil {
+		return errors.Wrap(err, "could not verify new payload")
+	}
 
 	// We add a proposer score boost to fork choice for the block root if applicable, right after
 	// running a successful state transition for the block.
-	if err := s.cfg.ForkChoiceStore.BoostProposerRoot(
-		ctx, signed.Block().Slot(), blockRoot, s.genesisTime,
-	); err != nil {
-		return err
-	}
-
-	if err := s.savePostStateInfo(ctx, blockRoot, signed, postState, false /* reg sync */); err != nil {
+	secondsIntoSlot := uint64(time.Since(s.genesisTime).Seconds()) % params.BeaconConfig().SecondsPerSlot
+	if err := s.cfg.ForkChoiceStore.BoostProposerRoot(ctx, &forkchoicetypes.ProposerBoostRootArgs{
+		BlockRoot:       blockRoot,
+		BlockSlot:       signed.Block().Slot(),
+		CurrentSlot:     slots.SinceGenesis(s.genesisTime),
+		SecondsIntoSlot: secondsIntoSlot,
+	}); err != nil {
 		return err
 	}
 
@@ -174,9 +191,8 @@ func (s *Service) onBlock(ctx context.Context, signed block.SignedBeaconBlock, b
 	if err := s.updateHead(ctx, balances); err != nil {
 		log.WithError(err).Warn("Could not update head")
 	}
-
-	if err := s.saveSyncedTipsDB(ctx); err != nil {
-		return errors.Wrap(err, "could not save synced tips")
+	if _, err := s.notifyForkchoiceUpdate(ctx, s.headBlock().Block(), s.headRoot(), bytesutil.ToBytes32(finalized.Root)); err != nil {
+		return err
 	}
 
 	if err := s.pruneCanonicalAttsFromPool(ctx, blockRoot, signed); err != nil {
@@ -222,14 +238,19 @@ func (s *Service) onBlock(ctx context.Context, signed block.SignedBeaconBlock, b
 		if err := s.cfg.ForkChoiceStore.Prune(ctx, fRoot); err != nil {
 			return errors.Wrap(err, "could not prune proto array fork choice nodes")
 		}
+		isOptimistic, err := s.cfg.ForkChoiceStore.IsOptimistic(ctx, fRoot)
+		if err != nil {
+			return errors.Wrap(err, "could not check if node is optimistically synced")
+		}
 		go func() {
 			// Send an event regarding the new finalized checkpoint over a common event feed.
 			s.cfg.StateNotifier.StateFeed().Send(&feed.Event{
 				Type: statefeed.FinalizedCheckpoint,
 				Data: &ethpbv1.EventFinalizedCheckpoint{
-					Epoch: postState.FinalizedCheckpoint().Epoch,
-					Block: postState.FinalizedCheckpoint().Root,
-					State: signed.Block().StateRoot(),
+					Epoch:               postState.FinalizedCheckpoint().Epoch,
+					Block:               postState.FinalizedCheckpoint().Root,
+					State:               signed.Block().StateRoot(),
+					ExecutionOptimistic: isOptimistic,
 				},
 			})
 
@@ -250,6 +271,24 @@ func (s *Service) onBlock(ctx context.Context, signed block.SignedBeaconBlock, b
 	return s.handleEpochBoundary(ctx, postState)
 }
 
+func getStateVersionAndPayload(st state.BeaconState) (int, *ethpb.ExecutionPayloadHeader, error) {
+	if st == nil {
+		return 0, nil, errors.New("nil state")
+	}
+	var preStateHeader *ethpb.ExecutionPayloadHeader
+	var err error
+	preStateVersion := st.Version()
+	switch preStateVersion {
+	case version.Phase0, version.Altair:
+	default:
+		preStateHeader, err = st.LatestExecutionPayloadHeader()
+		if err != nil {
+			return 0, nil, err
+		}
+	}
+	return preStateVersion, preStateHeader, nil
+}
+
 func (s *Service) onBlockBatch(ctx context.Context, blks []block.SignedBeaconBlock,
 	blockRoots [][32]byte) ([]*ethpb.Checkpoint, []*ethpb.Checkpoint, error) {
 	ctx, span := trace.StartSpan(ctx, "blockChain.onBlockBatch")
@@ -258,6 +297,11 @@ func (s *Service) onBlockBatch(ctx context.Context, blks []block.SignedBeaconBlo
 	if len(blks) == 0 || len(blockRoots) == 0 {
 		return nil, nil, errors.New("no blocks provided")
 	}
+
+	if len(blks) != len(blockRoots) {
+		return nil, nil, errWrongBlockCount
+	}
+
 	if err := helpers.BeaconBlockIsNil(blks[0]); err != nil {
 		return nil, nil, err
 	}
@@ -282,9 +326,24 @@ func (s *Service) onBlockBatch(ctx context.Context, blks []block.SignedBeaconBlo
 		PublicKeys: []bls.PublicKey{},
 		Messages:   [][32]byte{},
 	}
+	type versionAndHeader struct {
+		version int
+		header  *ethpb.ExecutionPayloadHeader
+	}
+	preVersionAndHeaders := make([]*versionAndHeader, len(blks))
+	postVersionAndHeaders := make([]*versionAndHeader, len(blks))
 	var set *bls.SignatureBatch
 	boundaries := make(map[[32]byte]state.BeaconState)
 	for i, b := range blks {
+		v, h, err := getStateVersionAndPayload(preState)
+		if err != nil {
+			return nil, nil, err
+		}
+		preVersionAndHeaders[i] = &versionAndHeader{
+			version: v,
+			header:  h,
+		}
+
 		set, preState, err = transition.ExecuteStateTransitionNoVerifyAnySig(ctx, preState, b)
 		if err != nil {
 			return nil, nil, err
@@ -292,12 +351,18 @@ func (s *Service) onBlockBatch(ctx context.Context, blks []block.SignedBeaconBlo
 		// Save potential boundary states.
 		if slots.IsEpochStart(preState.Slot()) {
 			boundaries[blockRoots[i]] = preState.Copy()
-			if err := s.handleEpochBoundary(ctx, preState); err != nil {
-				return nil, nil, errors.Wrap(err, "could not handle epoch boundary state")
-			}
 		}
 		jCheckpoints[i] = preState.CurrentJustifiedCheckpoint()
 		fCheckpoints[i] = preState.FinalizedCheckpoint()
+
+		v, h, err = getStateVersionAndPayload(preState)
+		if err != nil {
+			return nil, nil, err
+		}
+		postVersionAndHeaders[i] = &versionAndHeader{
+			version: v,
+			header:  h,
+		}
 		sigSet.Join(set)
 	}
 	verify, err := sigSet.Verify()
@@ -307,6 +372,26 @@ func (s *Service) onBlockBatch(ctx context.Context, blks []block.SignedBeaconBlo
 	if !verify {
 		return nil, nil, errors.New("batch block signature verification failed")
 	}
+
+	// blocks have been verified, add them to forkchoice and call the engine
+	for i, b := range blks {
+		s.saveInitSyncBlock(blockRoots[i], b)
+		if err := s.insertBlockToForkChoiceStore(ctx, b.Block(), blockRoots[i], fCheckpoints[i], jCheckpoints[i]); err != nil {
+			return nil, nil, err
+		}
+		if err := s.notifyNewPayload(ctx,
+			preVersionAndHeaders[i].version,
+			postVersionAndHeaders[i].version,
+			preVersionAndHeaders[i].header,
+			postVersionAndHeaders[i].header, b, blockRoots[i]); err != nil {
+			return nil, nil, err
+		}
+
+		if _, err := s.notifyForkchoiceUpdate(ctx, b.Block(), blockRoots[i], bytesutil.ToBytes32(fCheckpoints[i].Root)); err != nil {
+			return nil, nil, err
+		}
+	}
+
 	for r, st := range boundaries {
 		if err := s.cfg.StateGen.SaveState(ctx, r, st); err != nil {
 			return nil, nil, err
@@ -328,15 +413,6 @@ func (s *Service) onBlockBatch(ctx context.Context, blks []block.SignedBeaconBlo
 // their state summaries and split them off to relative hot/cold storage.
 func (s *Service) handleBlockAfterBatchVerify(ctx context.Context, signed block.SignedBeaconBlock,
 	blockRoot [32]byte, fCheckpoint, jCheckpoint *ethpb.Checkpoint) error {
-	b := signed.Block()
-
-	s.saveInitSyncBlock(blockRoot, signed)
-	if err := s.insertBlockToForkChoiceStore(ctx, b, blockRoot, fCheckpoint, jCheckpoint); err != nil {
-		return err
-	}
-	if err := s.saveSyncedTipsDB(ctx); err != nil {
-		return errors.Wrap(err, "could not save synced tips")
-	}
 
 	if err := s.cfg.BeaconDB.SaveStateSummary(ctx, &ethpb.StateSummary{
 		Slot: signed.Block().Slot(),
@@ -452,13 +528,27 @@ func (s *Service) insertBlockToForkChoiceStore(ctx context.Context, blk block.Be
 		return err
 	}
 	// Feed in block to fork choice store.
-	if err := s.cfg.ForkChoiceStore.ProcessBlock(ctx,
-		blk.Slot(), root, bytesutil.ToBytes32(blk.ParentRoot()), bytesutil.ToBytes32(blk.Body().Graffiti()),
-		jCheckpoint.Epoch,
-		fCheckpoint.Epoch); err != nil {
-		return errors.Wrap(err, "could not process block for proto array fork choice")
+
+	payloadHash, err := getBlockPayloadHash(blk)
+	if err != nil {
+		return err
 	}
-	return nil
+	return s.cfg.ForkChoiceStore.InsertOptimisticBlock(ctx,
+		blk.Slot(), root, bytesutil.ToBytes32(blk.ParentRoot()), payloadHash,
+		jCheckpoint.Epoch,
+		fCheckpoint.Epoch)
+}
+
+func getBlockPayloadHash(blk block.BeaconBlock) ([32]byte, error) {
+	payloadHash := [32]byte{}
+	if blocks.IsPreBellatrixVersion(blk.Version()) {
+		return payloadHash, nil
+	}
+	payload, err := blk.Body().ExecutionPayload()
+	if err != nil {
+		return payloadHash, err
+	}
+	return bytesutil.ToBytes32(payload.BlockHash), nil
 }
 
 // This saves post state info to DB or cache. This also saves post state info to fork choice store.
@@ -509,12 +599,3 @@ func (s *Service) pruneCanonicalAttsFromPool(ctx context.Context, r [32]byte, b
 	}
 	return nil
 }
-
-// Saves synced and validated tips to DB.
-func (s *Service) saveSyncedTipsDB(ctx context.Context) error {
-	tips := s.cfg.ForkChoiceStore.SyncedTips()
-	if len(tips) == 0 {
-		return nil
-	}
-	return s.cfg.BeaconDB.UpdateValidatedTips(ctx, tips)
-}

beacon-chain/blockchain/process_block_helpers.go

@@ -247,10 +247,19 @@ func (s *Service) updateFinalized(ctx context.Context, cp *ethpb.Checkpoint) err
 	}
 
 	fRoot := bytesutil.ToBytes32(cp.Root)
+	optimistic, err := s.cfg.ForkChoiceStore.IsOptimistic(ctx, fRoot)
+	if err != nil {
+		return err
+	}
+	if !optimistic {
+		err = s.cfg.BeaconDB.SaveLastValidatedCheckpoint(ctx, cp)
+		if err != nil {
+			return err
+		}
+	}
 	if err := s.cfg.StateGen.MigrateToCold(ctx, fRoot); err != nil {
 		return errors.Wrap(err, "could not migrate to cold")
 	}
-
 	return nil
 }
 
@@ -366,14 +375,17 @@ func (s *Service) fillInForkChoiceMissingBlocks(ctx context.Context, blk block.B
 	for i := len(pendingNodes) - 1; i >= 0; i-- {
 		b := pendingNodes[i]
 		r := pendingRoots[i]
-		if err := s.cfg.ForkChoiceStore.ProcessBlock(ctx,
-			b.Slot(), r, bytesutil.ToBytes32(b.ParentRoot()), bytesutil.ToBytes32(b.Body().Graffiti()),
+		payloadHash, err := getBlockPayloadHash(blk)
+		if err != nil {
+			return err
+		}
+		if err := s.cfg.ForkChoiceStore.InsertOptimisticBlock(ctx,
+			b.Slot(), r, bytesutil.ToBytes32(b.ParentRoot()), payloadHash,
 			jCheckpoint.Epoch,
 			fCheckpoint.Epoch); err != nil {
 			return errors.Wrap(err, "could not process block for proto array fork choice")
 		}
 	}
-
 	return nil
 }
 

beacon-chain/blockchain/receive_attestation.go

@@ -161,14 +161,36 @@ func (s *Service) spawnProcessAttestationsRoutine(stateFeed *event.Feed) {
 					log.WithError(err).Errorf("Unable to get justified balances for root %v", justified.Root)
 					continue
 				}
+				prevHead := s.headRoot()
 				if err := s.updateHead(s.ctx, balances); err != nil {
 					log.WithError(err).Warn("Resolving fork due to new attestation")
 				}
+				s.notifyEngineIfChangedHead(prevHead)
 			}
 		}
 	}()
 }
 
+// This calls notify Forkchoice Update in the event that the head has changed
+func (s *Service) notifyEngineIfChangedHead(prevHead [32]byte) {
+	if s.headRoot() == prevHead {
+		return
+	}
+	finalized := s.store.FinalizedCheckpt()
+	if finalized == nil {
+		log.WithError(errNilFinalizedInStore).Error("could not get finalized checkpoint")
+		return
+	}
+	_, err := s.notifyForkchoiceUpdate(s.ctx,
+		s.headBlock().Block(),
+		s.headRoot(),
+		bytesutil.ToBytes32(finalized.Root),
+	)
+	if err != nil {
+		log.WithError(err).Error("could not notify forkchoice update")
+	}
+}
+
 // This processes fork choice attestations from the pool to account for validator votes and fork choice.
 func (s *Service) processAttestations(ctx context.Context) {
 	atts := s.cfg.AttPool.ForkchoiceAttestations()

beacon-chain/blockchain/receive_attestation_test.go

@@ -47,13 +47,17 @@ func TestVerifyLMDFFGConsistent_NotOK(t *testing.T) {
 
 	b32 := util.NewBeaconBlock()
 	b32.Block.Slot = 32
-	require.NoError(t, service.cfg.BeaconDB.SaveBlock(ctx, wrapper.WrappedPhase0SignedBeaconBlock(b32)))
+	wsb, err := wrapper.WrappedSignedBeaconBlock(b32)
+	require.NoError(t, err)
+	require.NoError(t, service.cfg.BeaconDB.SaveBlock(ctx, wsb))
 	r32, err := b32.Block.HashTreeRoot()
 	require.NoError(t, err)
 	b33 := util.NewBeaconBlock()
 	b33.Block.Slot = 33
 	b33.Block.ParentRoot = r32[:]
-	require.NoError(t, service.cfg.BeaconDB.SaveBlock(ctx, wrapper.WrappedPhase0SignedBeaconBlock(b33)))
+	wsb, err = wrapper.WrappedSignedBeaconBlock(b33)
+	require.NoError(t, err)
+	require.NoError(t, service.cfg.BeaconDB.SaveBlock(ctx, wsb))
 	r33, err := b33.Block.HashTreeRoot()
 	require.NoError(t, err)
 
@@ -74,13 +78,17 @@ func TestVerifyLMDFFGConsistent_OK(t *testing.T) {
 
 	b32 := util.NewBeaconBlock()
 	b32.Block.Slot = 32
-	require.NoError(t, service.cfg.BeaconDB.SaveBlock(ctx, wrapper.WrappedPhase0SignedBeaconBlock(b32)))
+	wsb, err := wrapper.WrappedSignedBeaconBlock(b32)
+	require.NoError(t, err)
+	require.NoError(t, service.cfg.BeaconDB.SaveBlock(ctx, wsb))
 	r32, err := b32.Block.HashTreeRoot()
 	require.NoError(t, err)
 	b33 := util.NewBeaconBlock()
 	b33.Block.Slot = 33
 	b33.Block.ParentRoot = r32[:]
-	require.NoError(t, service.cfg.BeaconDB.SaveBlock(ctx, wrapper.WrappedPhase0SignedBeaconBlock(b33)))
+	wsb, err = wrapper.WrappedSignedBeaconBlock(b33)
+	require.NoError(t, err)
+	require.NoError(t, service.cfg.BeaconDB.SaveBlock(ctx, wsb))
 	r33, err := b33.Block.HashTreeRoot()
 	require.NoError(t, err)
 
@@ -111,9 +119,45 @@ func TestProcessAttestations_Ok(t *testing.T) {
 	copied, err = transition.ProcessSlots(ctx, copied, 1)
 	require.NoError(t, err)
 	require.NoError(t, service.cfg.BeaconDB.SaveState(ctx, copied, tRoot))
-	require.NoError(t, service.cfg.ForkChoiceStore.ProcessBlock(ctx, 0, tRoot, tRoot, tRoot, 1, 1))
+	require.NoError(t, service.cfg.ForkChoiceStore.InsertOptimisticBlock(ctx, 0, tRoot, tRoot, params.BeaconConfig().ZeroHash, 1, 1))
 	require.NoError(t, service.cfg.AttPool.SaveForkchoiceAttestations(atts))
 	service.processAttestations(ctx)
 	require.Equal(t, 0, len(service.cfg.AttPool.ForkchoiceAttestations()))
 	require.LogsDoNotContain(t, hook, "Could not process attestation for fork choice")
 }
+
+func TestNotifyEngineIfChangedHead(t *testing.T) {
+	hook := logTest.NewGlobal()
+	ctx := context.Background()
+	opts := testServiceOptsWithDB(t)
+
+	service, err := NewService(ctx, opts...)
+	require.NoError(t, err)
+
+	service.notifyEngineIfChangedHead(service.headRoot())
+	hookErr := "could not notify forkchoice update"
+	finalizedErr := "could not get finalized checkpoint"
+	require.LogsDoNotContain(t, hook, finalizedErr)
+	require.LogsDoNotContain(t, hook, hookErr)
+	service.notifyEngineIfChangedHead([32]byte{'a'})
+	require.LogsContain(t, hook, finalizedErr)
+
+	hook.Reset()
+	b := util.NewBeaconBlock()
+	b.Block.Slot = 1
+	wsb, err := wrapper.WrappedSignedBeaconBlock(b)
+	require.NoError(t, err)
+	require.NoError(t, service.cfg.BeaconDB.SaveBlock(ctx, wsb))
+	r, err := b.Block.HashTreeRoot()
+	require.NoError(t, err)
+	finalized := &ethpb.Checkpoint{Root: r[:], Epoch: 0}
+	service.head = &head{
+		slot:  1,
+		root:  r,
+		block: wsb,
+	}
+	service.store.SetFinalizedCheckpt(finalized)
+	service.notifyEngineIfChangedHead([32]byte{'b'})
+	require.LogsDoNotContain(t, hook, finalizedErr)
+	require.LogsDoNotContain(t, hook, hookErr)
+}

beacon-chain/blockchain/receive_block.go

@@ -64,7 +64,9 @@ func (s *Service) ReceiveBlock(ctx context.Context, block block.SignedBeaconBloc
 		return err
 	}
 	// Log state transition data.
-	logStateTransitionData(blockCopy.Block())
+	if err := logStateTransitionData(blockCopy.Block()); err != nil {
+		return err
+	}
 
 	return nil
 }

beacon-chain/blockchain/receive_block_test.go

@@ -132,6 +132,7 @@ func TestService_ReceiveBlock(t *testing.T) {
 				WithExitPool(voluntaryexits.NewPool()),
 				WithStateNotifier(&blockchainTesting.MockStateNotifier{RecordEvents: true}),
 				WithStateGen(stategen.New(beaconDB)),
+				WithFinalizedStateAtStartUp(genesis),
 			}
 			s, err := NewService(ctx, opts...)
 			require.NoError(t, err)
@@ -143,7 +144,9 @@ func TestService_ReceiveBlock(t *testing.T) {
 			s.store.SetFinalizedCheckpt(&ethpb.Checkpoint{Root: gRoot[:]})
 			root, err := tt.args.block.Block.HashTreeRoot()
 			require.NoError(t, err)
-			err = s.ReceiveBlock(ctx, wrapper.WrappedPhase0SignedBeaconBlock(tt.args.block), root)
+			wsb, err := wrapper.WrappedSignedBeaconBlock(tt.args.block)
+			require.NoError(t, err)
+			err = s.ReceiveBlock(ctx, wsb, root)
 			if tt.wantedErr != "" {
 				assert.ErrorContains(t, tt.wantedErr, err)
 			} else {
@@ -184,7 +187,9 @@ func TestService_ReceiveBlockUpdateHead(t *testing.T) {
 	wg := sync.WaitGroup{}
 	wg.Add(1)
 	go func() {
-		require.NoError(t, s.ReceiveBlock(ctx, wrapper.WrappedPhase0SignedBeaconBlock(b), root))
+		wsb, err := wrapper.WrappedSignedBeaconBlock(b)
+		require.NoError(t, err)
+		require.NoError(t, s.ReceiveBlock(ctx, wsb, root))
 		wg.Done()
 	}()
 	wg.Wait()
@@ -192,7 +197,7 @@ func TestService_ReceiveBlockUpdateHead(t *testing.T) {
 		t.Errorf("Received %d state notifications, expected at least 1", recvd)
 	}
 	// Verify fork choice has processed the block. (Genesis block and the new block)
-	assert.Equal(t, 2, len(s.cfg.ForkChoiceStore.Nodes()))
+	assert.Equal(t, 2, s.cfg.ForkChoiceStore.NodeCount())
 }
 
 func TestService_ReceiveBlockBatch(t *testing.T) {
@@ -260,7 +265,9 @@ func TestService_ReceiveBlockBatch(t *testing.T) {
 			s.store.SetFinalizedCheckpt(&ethpb.Checkpoint{Root: gRoot[:]})
 			root, err := tt.args.block.Block.HashTreeRoot()
 			require.NoError(t, err)
-			blks := []block.SignedBeaconBlock{wrapper.WrappedPhase0SignedBeaconBlock(tt.args.block)}
+			wsb, err := wrapper.WrappedSignedBeaconBlock(tt.args.block)
+			require.NoError(t, err)
+			blks := []block.SignedBeaconBlock{wsb}
 			roots := [][32]byte{root}
 			err = s.ReceiveBlockBatch(ctx, blks, roots)
 			if tt.wantedErr != "" {
@@ -282,7 +289,9 @@ func TestService_HasInitSyncBlock(t *testing.T) {
 	if s.HasInitSyncBlock(r) {
 		t.Error("Should not have block")
 	}
-	s.saveInitSyncBlock(r, wrapper.WrappedPhase0SignedBeaconBlock(util.NewBeaconBlock()))
+	wsb, err := wrapper.WrappedSignedBeaconBlock(util.NewBeaconBlock())
+	require.NoError(t, err)
+	s.saveInitSyncBlock(r, wsb)
 	if !s.HasInitSyncBlock(r) {
 		t.Error("Should have block")
 	}

beacon-chain/blockchain/service.go

@@ -3,6 +3,7 @@
 package blockchain
 
 import (
+	"bytes"
 	"context"
 	"fmt"
 	"runtime"
@@ -21,6 +22,7 @@ import (
 	"github.com/prysmaticlabs/prysm/beacon-chain/core/transition"
 	"github.com/prysmaticlabs/prysm/beacon-chain/db"
 	f "github.com/prysmaticlabs/prysm/beacon-chain/forkchoice"
+	doublylinkedtree "github.com/prysmaticlabs/prysm/beacon-chain/forkchoice/doubly-linked-tree"
 	"github.com/prysmaticlabs/prysm/beacon-chain/forkchoice/protoarray"
 	"github.com/prysmaticlabs/prysm/beacon-chain/operations/attestations"
 	"github.com/prysmaticlabs/prysm/beacon-chain/operations/slashings"
@@ -31,6 +33,7 @@ import (
 	"github.com/prysmaticlabs/prysm/beacon-chain/state"
 	"github.com/prysmaticlabs/prysm/beacon-chain/state/stategen"
 	"github.com/prysmaticlabs/prysm/cmd/beacon-chain/flags"
+	"github.com/prysmaticlabs/prysm/config/features"
 	"github.com/prysmaticlabs/prysm/config/params"
 	"github.com/prysmaticlabs/prysm/encoding/bytesutil"
 	ethpb "github.com/prysmaticlabs/prysm/proto/prysm/v1alpha1"
@@ -83,6 +86,7 @@ type config struct {
 	StateGen                *stategen.State
 	SlasherAttestationsFeed *event.Feed
 	WeakSubjectivityCheckpt *ethpb.Checkpoint
+	BlockFetcher            powchain.POWBlockFetcher
 	FinalizedStateAtStartUp state.BeaconState
 	ExecutionEngineCaller   enginev1.Caller
 }
@@ -124,7 +128,7 @@ func (s *Service) Start() {
 	saved := s.cfg.FinalizedStateAtStartUp
 
 	if saved != nil && !saved.IsNil() {
-		if err := s.startFromSavedState(saved); err != nil {
+		if err := s.StartFromSavedState(saved); err != nil {
 			log.Fatal(err)
 		}
 	} else {
@@ -132,6 +136,7 @@ func (s *Service) Start() {
 			log.Fatal(err)
 		}
 	}
+	s.spawnProcessAttestationsRoutine(s.cfg.StateNotifier.StateFeed())
 }
 
 // Stop the blockchain service's main event loop and associated goroutines.
@@ -160,9 +165,9 @@ func (s *Service) Status() error {
 	return nil
 }
 
-func (s *Service) startFromSavedState(saved state.BeaconState) error {
+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)
+	s.genesisTime = time.Unix(int64(saved.GenesisTime()), 0) // lint:ignore uintcast -- Genesis time will not exceed int64 in your lifetime.
 	s.cfg.AttService.SetGenesisTime(saved.GenesisTime())
 
 	originRoot, err := s.originRootFromSavedState(s.ctx)
@@ -186,21 +191,45 @@ func (s *Service) startFromSavedState(saved state.BeaconState) error {
 	}
 	s.store = store.New(justified, finalized)
 
-	store := protoarray.New(justified.Epoch, finalized.Epoch, bytesutil.ToBytes32(finalized.Root))
+	var store f.ForkChoicer
+	fRoot := bytesutil.ToBytes32(finalized.Root)
+	if features.Get().EnableForkChoiceDoublyLinkedTree {
+		store = doublylinkedtree.New(justified.Epoch, finalized.Epoch)
+	} else {
+		store = protoarray.New(justified.Epoch, finalized.Epoch, fRoot)
+	}
 	s.cfg.ForkChoiceStore = store
-
-	if err := s.loadSyncedTips(originRoot, saved.Slot()); err != nil {
-		return err
-	}
-
-	ss, err := slots.EpochStart(finalized.Epoch)
+	fb, err := s.cfg.BeaconDB.Block(s.ctx, s.ensureRootNotZeros(fRoot))
 	if err != nil {
-		return errors.Wrap(err, "could not get start slot of finalized epoch")
+		return errors.Wrap(err, "could not get finalized checkpoint block")
 	}
+	if fb == nil {
+		return errNilFinalizedInStore
+	}
+	payloadHash, err := getBlockPayloadHash(fb.Block())
+	if err != nil {
+		return errors.Wrap(err, "could not get execution payload hash")
+	}
+	fSlot := fb.Block().Slot()
+	if err := store.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")
+	}
+
+	lastValidatedCheckpoint, err := s.cfg.BeaconDB.LastValidatedCheckpoint(s.ctx)
+	if err != nil {
+		return errors.Wrap(err, "could not get last validated checkpoint")
+	}
+	if bytes.Equal(finalized.Root, lastValidatedCheckpoint.Root) {
+		if err := store.SetOptimisticToValid(s.ctx, fRoot); err != nil {
+			return errors.Wrap(err, "could not set finalized block as validated")
+		}
+	}
+
 	h := s.headBlock().Block()
-	if h.Slot() > ss {
+	if h.Slot() > fSlot {
 		log.WithFields(logrus.Fields{
-			"startSlot": ss,
+			"startSlot": fSlot,
 			"endSlot":   h.Slot(),
 		}).Info("Loading blocks to fork choice store, this may take a while.")
 		if err := s.fillInForkChoiceMissingBlocks(s.ctx, h, finalized, justified); err != nil {
@@ -223,14 +252,12 @@ func (s *Service) startFromSavedState(saved state.BeaconState) error {
 		},
 	})
 
-	s.spawnProcessAttestationsRoutine(s.cfg.StateNotifier.StateFeed())
-
 	return nil
 }
 
 func (s *Service) originRootFromSavedState(ctx context.Context) ([32]byte, error) {
 	// first check if we have started from checkpoint sync and have a root
-	originRoot, err := s.cfg.BeaconDB.OriginBlockRoot(ctx)
+	originRoot, err := s.cfg.BeaconDB.OriginCheckpointBlockRoot(ctx)
 	if err == nil {
 		return originRoot, nil
 	}
@@ -238,7 +265,7 @@ func (s *Service) originRootFromSavedState(ctx context.Context) ([32]byte, error
 		return originRoot, errors.Wrap(err, "could not retrieve checkpoint sync chain origin data from db")
 	}
 
-	// we got here because OriginBlockRoot gave us an ErrNotFound. this means the node was started from a genesis state,
+	// we got here because OriginCheckpointBlockRoot gave us an ErrNotFound. this means the node was started from a genesis state,
 	// so we should have a value for GenesisBlock
 	genesisBlock, err := s.cfg.BeaconDB.GenesisBlock(ctx)
 	if err != nil {
@@ -333,7 +360,6 @@ func (s *Service) startFromPOWChain() error {
 		stateChannel := make(chan *feed.Event, 1)
 		stateSub := s.cfg.StateNotifier.StateFeed().Subscribe(stateChannel)
 		defer stateSub.Unsubscribe()
-		s.spawnProcessAttestationsRoutine(s.cfg.StateNotifier.StateFeed())
 		for {
 			select {
 			case event := <-stateChannel:
@@ -447,15 +473,22 @@ func (s *Service) saveGenesisData(ctx context.Context, genesisState state.Beacon
 	genesisCheckpoint := genesisState.FinalizedCheckpoint()
 	s.store = store.New(genesisCheckpoint, genesisCheckpoint)
 
-	if err := s.cfg.ForkChoiceStore.ProcessBlock(ctx,
+	payloadHash, err := getBlockPayloadHash(genesisBlk.Block())
+	if err != nil {
+		return err
+	}
+	if err := s.cfg.ForkChoiceStore.InsertOptimisticBlock(ctx,
 		genesisBlk.Block().Slot(),
 		genesisBlkRoot,
 		params.BeaconConfig().ZeroHash,
-		[32]byte{},
+		payloadHash,
 		genesisCheckpoint.Epoch,
 		genesisCheckpoint.Epoch); err != nil {
 		log.Fatalf("Could not process genesis block for fork choice: %v", err)
 	}
+	if err := s.cfg.ForkChoiceStore.SetOptimisticToValid(ctx, genesisBlkRoot); err != nil {
+		log.Fatalf("Could not set optimistic status of genesis block to false: %v", err)
+	}
 
 	s.setHead(genesisBlkRoot, genesisBlk, genesisState)
 	return nil

beacon-chain/blockchain/service_test.go

@@ -8,7 +8,6 @@ import (
 	"time"
 
 	"github.com/ethereum/go-ethereum/common"
-	types "github.com/prysmaticlabs/eth2-types"
 	"github.com/prysmaticlabs/prysm/async/event"
 	"github.com/prysmaticlabs/prysm/beacon-chain/blockchain/store"
 	mock "github.com/prysmaticlabs/prysm/beacon-chain/blockchain/testing"
@@ -20,6 +19,7 @@ import (
 	"github.com/prysmaticlabs/prysm/beacon-chain/core/transition"
 	"github.com/prysmaticlabs/prysm/beacon-chain/db"
 	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"
 	"github.com/prysmaticlabs/prysm/beacon-chain/operations/attestations"
 	"github.com/prysmaticlabs/prysm/beacon-chain/p2p"
@@ -144,7 +144,9 @@ func TestChainStartStop_Initialized(t *testing.T) {
 	genesisBlk := util.NewBeaconBlock()
 	blkRoot, err := genesisBlk.Block.HashTreeRoot()
 	require.NoError(t, err)
-	require.NoError(t, beaconDB.SaveBlock(ctx, wrapper.WrappedPhase0SignedBeaconBlock(genesisBlk)))
+	wsb, err := wrapper.WrappedSignedBeaconBlock(genesisBlk)
+	require.NoError(t, err)
+	require.NoError(t, beaconDB.SaveBlock(ctx, wsb))
 	s, err := util.NewBeaconState()
 	require.NoError(t, err)
 	require.NoError(t, s.SetSlot(1))
@@ -153,6 +155,11 @@ func TestChainStartStop_Initialized(t *testing.T) {
 	require.NoError(t, beaconDB.SaveGenesisBlockRoot(ctx, blkRoot))
 	require.NoError(t, beaconDB.SaveJustifiedCheckpoint(ctx, &ethpb.Checkpoint{Root: blkRoot[:]}))
 	require.NoError(t, beaconDB.SaveFinalizedCheckpoint(ctx, &ethpb.Checkpoint{Root: blkRoot[:]}))
+	ss := &ethpb.StateSummary{
+		Slot: 1,
+		Root: blkRoot[:],
+	}
+	require.NoError(t, beaconDB.SaveStateSummary(ctx, ss))
 	chainService.cfg.FinalizedStateAtStartUp = s
 	// Test the start function.
 	chainService.Start()
@@ -164,74 +171,6 @@ func TestChainStartStop_Initialized(t *testing.T) {
 	require.LogsContain(t, hook, "data already exists")
 }
 
-func TestChainStart_SyncedTipsInDB(t *testing.T) {
-	ctx := context.Background()
-	beaconDB := testDB.SetupDB(t)
-
-	chainService := setupBeaconChain(t, beaconDB)
-
-	genesisBlk := util.NewBeaconBlock()
-	blkRoot, err := genesisBlk.Block.HashTreeRoot()
-	require.NoError(t, err)
-	require.NoError(t, beaconDB.SaveBlock(ctx, wrapper.WrappedPhase0SignedBeaconBlock(genesisBlk)))
-	s, err := util.NewBeaconState()
-	require.NoError(t, err)
-	require.NoError(t, s.SetSlot(1))
-	require.NoError(t, beaconDB.SaveState(ctx, s, blkRoot))
-	require.NoError(t, beaconDB.SaveHeadBlockRoot(ctx, blkRoot))
-	require.NoError(t, beaconDB.SaveGenesisBlockRoot(ctx, blkRoot))
-	require.NoError(t, beaconDB.SaveJustifiedCheckpoint(ctx, &ethpb.Checkpoint{Root: blkRoot[:]}))
-	require.NoError(t, beaconDB.SaveFinalizedCheckpoint(ctx, &ethpb.Checkpoint{Root: blkRoot[:]}))
-	chainService.cfg.FinalizedStateAtStartUp = s
-
-	tips := make(map[[32]byte]types.Slot)
-	tips[bytesutil.ToBytes32([]byte{'a'})] = 1
-	tips[bytesutil.ToBytes32([]byte{'b'})] = 2
-	require.NoError(t, beaconDB.UpdateValidatedTips(ctx, tips))
-
-	// Test the start function.
-	chainService.Start()
-
-	// Test synced Tips in DB
-	tips2 := chainService.cfg.ForkChoiceStore.SyncedTips()
-	require.Equal(t, len(tips2), len(tips))
-	for k, v := range tips {
-		v2, ok := tips2[k]
-		require.Equal(t, true, ok)
-		require.Equal(t, v, v2)
-	}
-}
-
-func TestChainStart_SyncedTipsNotInDB(t *testing.T) {
-	ctx := context.Background()
-	beaconDB := testDB.SetupDB(t)
-
-	chainService := setupBeaconChain(t, beaconDB)
-
-	genesisBlk := util.NewBeaconBlock()
-	blkRoot, err := genesisBlk.Block.HashTreeRoot()
-	require.NoError(t, err)
-	require.NoError(t, beaconDB.SaveBlock(ctx, wrapper.WrappedPhase0SignedBeaconBlock(genesisBlk)))
-	s, err := util.NewBeaconState()
-	require.NoError(t, err)
-	require.NoError(t, s.SetSlot(1))
-	require.NoError(t, beaconDB.SaveState(ctx, s, blkRoot))
-	require.NoError(t, beaconDB.SaveHeadBlockRoot(ctx, blkRoot))
-	require.NoError(t, beaconDB.SaveGenesisBlockRoot(ctx, blkRoot))
-	require.NoError(t, beaconDB.SaveJustifiedCheckpoint(ctx, &ethpb.Checkpoint{Root: blkRoot[:]}))
-	require.NoError(t, beaconDB.SaveFinalizedCheckpoint(ctx, &ethpb.Checkpoint{Root: blkRoot[:]}))
-	chainService.cfg.FinalizedStateAtStartUp = s
-	// Test the start function.
-	chainService.Start()
-
-	// Test synced Tips in DB
-	tips := chainService.cfg.ForkChoiceStore.SyncedTips()
-	require.Equal(t, 1, len(tips))
-	slot, ok := tips[blkRoot]
-	require.Equal(t, true, ok)
-	require.Equal(t, types.Slot(1), slot)
-}
-
 func TestChainStartStop_GenesisZeroHashes(t *testing.T) {
 	hook := logTest.NewGlobal()
 	ctx := context.Background()
@@ -242,12 +181,16 @@ func TestChainStartStop_GenesisZeroHashes(t *testing.T) {
 	genesisBlk := util.NewBeaconBlock()
 	blkRoot, err := genesisBlk.Block.HashTreeRoot()
 	require.NoError(t, err)
-	require.NoError(t, beaconDB.SaveBlock(ctx, wrapper.WrappedPhase0SignedBeaconBlock(genesisBlk)))
+	wsb, err := wrapper.WrappedSignedBeaconBlock(genesisBlk)
+	require.NoError(t, err)
+	require.NoError(t, beaconDB.SaveBlock(ctx, wsb))
 	s, err := util.NewBeaconState()
 	require.NoError(t, err)
 	require.NoError(t, beaconDB.SaveState(ctx, s, blkRoot))
 	require.NoError(t, beaconDB.SaveGenesisBlockRoot(ctx, blkRoot))
+	require.NoError(t, beaconDB.SaveBlock(ctx, wsb))
 	require.NoError(t, beaconDB.SaveJustifiedCheckpoint(ctx, &ethpb.Checkpoint{Root: params.BeaconConfig().ZeroHash[:]}))
+	require.NoError(t, beaconDB.SaveFinalizedCheckpoint(ctx, &ethpb.Checkpoint{Root: blkRoot[:]}))
 	chainService.cfg.FinalizedStateAtStartUp = s
 	// Test the start function.
 	chainService.Start()
@@ -311,7 +254,9 @@ func TestChainService_CorrectGenesisRoots(t *testing.T) {
 	genesisBlk := util.NewBeaconBlock()
 	blkRoot, err := genesisBlk.Block.HashTreeRoot()
 	require.NoError(t, err)
-	require.NoError(t, beaconDB.SaveBlock(ctx, wrapper.WrappedPhase0SignedBeaconBlock(genesisBlk)))
+	wsb, err := wrapper.WrappedSignedBeaconBlock(genesisBlk)
+	require.NoError(t, err)
+	require.NoError(t, beaconDB.SaveBlock(ctx, wsb))
 	s, err := util.NewBeaconState()
 	require.NoError(t, err)
 	require.NoError(t, s.SetSlot(0))
@@ -338,7 +283,9 @@ func TestChainService_InitializeChainInfo(t *testing.T) {
 	genesisRoot, err := genesis.Block.HashTreeRoot()
 	require.NoError(t, err)
 	require.NoError(t, beaconDB.SaveGenesisBlockRoot(ctx, genesisRoot))
-	require.NoError(t, beaconDB.SaveBlock(ctx, wrapper.WrappedPhase0SignedBeaconBlock(genesis)))
+	wsb, err := wrapper.WrappedSignedBeaconBlock(genesis)
+	require.NoError(t, err)
+	require.NoError(t, beaconDB.SaveBlock(ctx, wsb))
 
 	finalizedSlot := params.BeaconConfig().SlotsPerEpoch*2 + 1
 	headBlock := util.NewBeaconBlock()
@@ -352,13 +299,17 @@ func TestChainService_InitializeChainInfo(t *testing.T) {
 	require.NoError(t, err)
 	require.NoError(t, beaconDB.SaveState(ctx, headState, headRoot))
 	require.NoError(t, beaconDB.SaveState(ctx, headState, genesisRoot))
-	require.NoError(t, beaconDB.SaveBlock(ctx, wrapper.WrappedPhase0SignedBeaconBlock(headBlock)))
+	wsb, err = wrapper.WrappedSignedBeaconBlock(headBlock)
+	require.NoError(t, err)
+	require.NoError(t, beaconDB.SaveBlock(ctx, wsb))
 	require.NoError(t, beaconDB.SaveFinalizedCheckpoint(ctx, &ethpb.Checkpoint{Epoch: slots.ToEpoch(finalizedSlot), Root: headRoot[:]}))
 	attSrv, err := attestations.NewService(ctx, &attestations.Config{})
 	require.NoError(t, err)
-	c, err := NewService(ctx, WithDatabase(beaconDB), WithStateGen(stategen.New(beaconDB)), WithAttestationService(attSrv), WithStateNotifier(&mock.MockStateNotifier{}), WithFinalizedStateAtStartUp(headState))
+	stateGen := stategen.New(beaconDB)
+	c, err := NewService(ctx, WithDatabase(beaconDB), WithStateGen(stateGen), WithAttestationService(attSrv), WithStateNotifier(&mock.MockStateNotifier{}), WithFinalizedStateAtStartUp(headState))
 	require.NoError(t, err)
-	require.NoError(t, c.startFromSavedState(headState))
+	require.NoError(t, stateGen.SaveState(ctx, headRoot, headState))
+	require.NoError(t, c.StartFromSavedState(headState))
 	headBlk, err := c.HeadBlock(ctx)
 	require.NoError(t, err)
 	assert.DeepEqual(t, headBlock, headBlk.Proto(), "Head block incorrect")
@@ -382,7 +333,9 @@ func TestChainService_InitializeChainInfo_SetHeadAtGenesis(t *testing.T) {
 	genesisRoot, err := genesis.Block.HashTreeRoot()
 	require.NoError(t, err)
 	require.NoError(t, beaconDB.SaveGenesisBlockRoot(ctx, genesisRoot))
-	require.NoError(t, beaconDB.SaveBlock(ctx, wrapper.WrappedPhase0SignedBeaconBlock(genesis)))
+	wsb, err := wrapper.WrappedSignedBeaconBlock(genesis)
+	require.NoError(t, err)
+	require.NoError(t, beaconDB.SaveBlock(ctx, wsb))
 
 	finalizedSlot := params.BeaconConfig().SlotsPerEpoch*2 + 1
 	headBlock := util.NewBeaconBlock()
@@ -396,17 +349,27 @@ func TestChainService_InitializeChainInfo_SetHeadAtGenesis(t *testing.T) {
 	require.NoError(t, err)
 	require.NoError(t, beaconDB.SaveState(ctx, headState, headRoot))
 	require.NoError(t, beaconDB.SaveState(ctx, headState, genesisRoot))
-	require.NoError(t, beaconDB.SaveBlock(ctx, wrapper.WrappedPhase0SignedBeaconBlock(headBlock)))
+	wsb, err = wrapper.WrappedSignedBeaconBlock(headBlock)
+	require.NoError(t, err)
+	require.NoError(t, beaconDB.SaveBlock(ctx, wsb))
 	attSrv, err := attestations.NewService(ctx, &attestations.Config{})
 	require.NoError(t, err)
-	c, err := NewService(ctx, WithDatabase(beaconDB), WithStateGen(stategen.New(beaconDB)), WithAttestationService(attSrv), WithStateNotifier(&mock.MockStateNotifier{}))
+	ss := &ethpb.StateSummary{
+		Slot: finalizedSlot,
+		Root: headRoot[:],
+	}
+	require.NoError(t, beaconDB.SaveStateSummary(ctx, ss))
+	require.NoError(t, beaconDB.SaveFinalizedCheckpoint(ctx, &ethpb.Checkpoint{Root: headRoot[:], Epoch: slots.ToEpoch(finalizedSlot)}))
+	stateGen := stategen.New(beaconDB)
+	c, err := NewService(ctx, WithDatabase(beaconDB), WithStateGen(stateGen), WithAttestationService(attSrv), WithStateNotifier(&mock.MockStateNotifier{}), WithFinalizedStateAtStartUp(headState))
 	require.NoError(t, err)
-	require.NoError(t, c.startFromSavedState(headState))
+
+	require.NoError(t, c.StartFromSavedState(headState))
 	s, err := c.HeadState(ctx)
 	require.NoError(t, err)
 	assert.DeepSSZEqual(t, headState.InnerStateUnsafe(), s.InnerStateUnsafe(), "Head state incorrect")
 	assert.Equal(t, genesisRoot, c.originBlockRoot, "Genesis block root incorrect")
-	assert.DeepEqual(t, genesis, c.head.block.Proto())
+	assert.DeepEqual(t, headBlock, c.head.block.Proto())
 }
 
 func TestChainService_InitializeChainInfo_HeadSync(t *testing.T) {
@@ -427,14 +390,18 @@ func TestChainService_InitializeChainInfo_HeadSync(t *testing.T) {
 	genesisRoot, err := genesisBlock.Block.HashTreeRoot()
 	require.NoError(t, err)
 	require.NoError(t, beaconDB.SaveGenesisBlockRoot(ctx, genesisRoot))
-	require.NoError(t, beaconDB.SaveBlock(ctx, wrapper.WrappedPhase0SignedBeaconBlock(genesisBlock)))
+	wsb, err := wrapper.WrappedSignedBeaconBlock(genesisBlock)
+	require.NoError(t, err)
+	require.NoError(t, beaconDB.SaveBlock(ctx, wsb))
 
 	finalizedBlock := util.NewBeaconBlock()
 	finalizedBlock.Block.Slot = finalizedSlot
 	finalizedBlock.Block.ParentRoot = genesisRoot[:]
 	finalizedRoot, err := finalizedBlock.Block.HashTreeRoot()
 	require.NoError(t, err)
-	require.NoError(t, beaconDB.SaveBlock(ctx, wrapper.WrappedPhase0SignedBeaconBlock(finalizedBlock)))
+	wsb, err = wrapper.WrappedSignedBeaconBlock(finalizedBlock)
+	require.NoError(t, err)
+	require.NoError(t, beaconDB.SaveBlock(ctx, wsb))
 
 	// Set head slot close to the finalization point, no head sync is triggered.
 	headBlock := util.NewBeaconBlock()
@@ -442,15 +409,16 @@ func TestChainService_InitializeChainInfo_HeadSync(t *testing.T) {
 	headBlock.Block.ParentRoot = finalizedRoot[:]
 	headRoot, err := headBlock.Block.HashTreeRoot()
 	require.NoError(t, err)
-	require.NoError(t, beaconDB.SaveBlock(ctx, wrapper.WrappedPhase0SignedBeaconBlock(headBlock)))
+	wsb, err = wrapper.WrappedSignedBeaconBlock(headBlock)
+	require.NoError(t, err)
+	require.NoError(t, beaconDB.SaveBlock(ctx, wsb))
 
 	headState, err := util.NewBeaconState()
 	require.NoError(t, err)
 	require.NoError(t, headState.SetSlot(headBlock.Block.Slot))
 	require.NoError(t, headState.SetGenesisValidatorsRoot(params.BeaconConfig().ZeroHash[:]))
-	require.NoError(t, beaconDB.SaveState(ctx, headState, genesisRoot))
-	require.NoError(t, beaconDB.SaveState(ctx, headState, finalizedRoot))
 	require.NoError(t, beaconDB.SaveState(ctx, headState, headRoot))
+	require.NoError(t, beaconDB.SaveState(ctx, headState, finalizedRoot))
 	require.NoError(t, beaconDB.SaveHeadBlockRoot(ctx, headRoot))
 	require.NoError(t, beaconDB.SaveFinalizedCheckpoint(ctx, &ethpb.Checkpoint{
 		Epoch: slots.ToEpoch(finalizedBlock.Block.Slot),
@@ -459,9 +427,10 @@ func TestChainService_InitializeChainInfo_HeadSync(t *testing.T) {
 
 	attSrv, err := attestations.NewService(ctx, &attestations.Config{})
 	require.NoError(t, err)
-	c, err := NewService(ctx, WithDatabase(beaconDB), WithStateGen(stategen.New(beaconDB)), WithAttestationService(attSrv), WithStateNotifier(&mock.MockStateNotifier{}), WithFinalizedStateAtStartUp(headState))
+	stateGen := stategen.New(beaconDB)
+	c, err := NewService(ctx, WithDatabase(beaconDB), WithStateGen(stateGen), WithAttestationService(attSrv), WithStateNotifier(&mock.MockStateNotifier{}), WithFinalizedStateAtStartUp(headState))
 	require.NoError(t, err)
-	require.NoError(t, c.startFromSavedState(headState))
+	require.NoError(t, c.StartFromSavedState(headState))
 	s, err := c.HeadState(ctx)
 	require.NoError(t, err)
 	assert.DeepSSZEqual(t, headState.InnerStateUnsafe(), s.InnerStateUnsafe(), "Head state incorrect")
@@ -477,7 +446,9 @@ func TestChainService_InitializeChainInfo_HeadSync(t *testing.T) {
 	headBlock.Block.ParentRoot = finalizedRoot[:]
 	headRoot, err = headBlock.Block.HashTreeRoot()
 	require.NoError(t, err)
-	require.NoError(t, beaconDB.SaveBlock(ctx, wrapper.WrappedPhase0SignedBeaconBlock(headBlock)))
+	wsb, err = wrapper.WrappedSignedBeaconBlock(headBlock)
+	require.NoError(t, err)
+	require.NoError(t, beaconDB.SaveBlock(ctx, wsb))
 	require.NoError(t, beaconDB.SaveState(ctx, headState, headRoot))
 	require.NoError(t, beaconDB.SaveHeadBlockRoot(ctx, headRoot))
 
@@ -506,7 +477,9 @@ func TestChainService_SaveHeadNoDB(t *testing.T) {
 	newState, err := util.NewBeaconState()
 	require.NoError(t, err)
 	require.NoError(t, s.cfg.StateGen.SaveState(ctx, r, newState))
-	require.NoError(t, s.saveHeadNoDB(ctx, wrapper.WrappedPhase0SignedBeaconBlock(blk), r, newState))
+	wsb, err := wrapper.WrappedSignedBeaconBlock(blk)
+	require.NoError(t, err)
+	require.NoError(t, s.saveHeadNoDB(ctx, wsb, r, newState))
 
 	newB, err := s.cfg.BeaconDB.HeadBlock(ctx)
 	require.NoError(t, err)
@@ -515,7 +488,7 @@ func TestChainService_SaveHeadNoDB(t *testing.T) {
 	}
 }
 
-func TestHasBlock_ForkChoiceAndDB(t *testing.T) {
+func TestHasBlock_ForkChoiceAndDB_ProtoArray(t *testing.T) {
 	ctx := context.Background()
 	beaconDB := testDB.SetupDB(t)
 	s := &Service{
@@ -528,7 +501,30 @@ func TestHasBlock_ForkChoiceAndDB(t *testing.T) {
 	require.NoError(t, err)
 	beaconState, err := util.NewBeaconState()
 	require.NoError(t, err)
-	require.NoError(t, s.insertBlockAndAttestationsToForkChoiceStore(ctx, wrapper.WrappedPhase0SignedBeaconBlock(block).Block(), r, beaconState))
+	wsb, err := wrapper.WrappedSignedBeaconBlock(block)
+	require.NoError(t, err)
+	require.NoError(t, s.insertBlockAndAttestationsToForkChoiceStore(ctx, wsb.Block(), r, beaconState))
+
+	assert.Equal(t, false, s.hasBlock(ctx, [32]byte{}), "Should not have block")
+	assert.Equal(t, true, s.hasBlock(ctx, r), "Should have block")
+}
+
+func TestHasBlock_ForkChoiceAndDB_DoublyLinkedTree(t *testing.T) {
+	ctx := context.Background()
+	beaconDB := testDB.SetupDB(t)
+	s := &Service{
+		cfg:   &config{ForkChoiceStore: doublylinkedtree.New(0, 0), BeaconDB: beaconDB},
+		store: &store.Store{},
+	}
+	s.store.SetFinalizedCheckpt(&ethpb.Checkpoint{Epoch: 0, Root: params.BeaconConfig().ZeroHash[:]})
+	block := util.NewBeaconBlock()
+	r, err := block.Block.HashTreeRoot()
+	require.NoError(t, err)
+	beaconState, err := util.NewBeaconState()
+	require.NoError(t, err)
+	wsb, err := wrapper.WrappedSignedBeaconBlock(block)
+	require.NoError(t, err)
+	require.NoError(t, s.insertBlockAndAttestationsToForkChoiceStore(ctx, wsb.Block(), r, beaconState))
 
 	assert.Equal(t, false, s.hasBlock(ctx, [32]byte{}), "Should not have block")
 	assert.Equal(t, true, s.hasBlock(ctx, r), "Should have block")
@@ -546,7 +542,9 @@ func TestServiceStop_SaveCachedBlocks(t *testing.T) {
 	block := util.NewBeaconBlock()
 	r, err := block.Block.HashTreeRoot()
 	require.NoError(t, err)
-	s.saveInitSyncBlock(r, wrapper.WrappedPhase0SignedBeaconBlock(block))
+	wsb, err := wrapper.WrappedSignedBeaconBlock(block)
+	require.NoError(t, err)
+	s.saveInitSyncBlock(r, wsb)
 	require.NoError(t, s.Stop())
 	require.Equal(t, true, s.cfg.BeaconDB.HasBlock(ctx, r))
 }
@@ -572,7 +570,9 @@ func BenchmarkHasBlockDB(b *testing.B) {
 		cfg: &config{BeaconDB: beaconDB},
 	}
 	block := util.NewBeaconBlock()
-	require.NoError(b, s.cfg.BeaconDB.SaveBlock(ctx, wrapper.WrappedPhase0SignedBeaconBlock(block)))
+	wsb, err := wrapper.WrappedSignedBeaconBlock(block)
+	require.NoError(b, err)
+	require.NoError(b, s.cfg.BeaconDB.SaveBlock(ctx, wsb))
 	r, err := block.Block.HashTreeRoot()
 	require.NoError(b, err)
 
@@ -582,7 +582,7 @@ func BenchmarkHasBlockDB(b *testing.B) {
 	}
 }
 
-func BenchmarkHasBlockForkChoiceStore(b *testing.B) {
+func BenchmarkHasBlockForkChoiceStore_ProtoArray(b *testing.B) {
 	ctx := context.Background()
 	beaconDB := testDB.SetupDB(b)
 	s := &Service{
@@ -590,13 +590,38 @@ func BenchmarkHasBlockForkChoiceStore(b *testing.B) {
 		store: &store.Store{},
 	}
 	s.store.SetFinalizedCheckpt(&ethpb.Checkpoint{Epoch: 0, Root: params.BeaconConfig().ZeroHash[:]})
+	blk := &ethpb.SignedBeaconBlock{Block: &ethpb.BeaconBlock{Body: &ethpb.BeaconBlockBody{}}}
+	r, err := blk.Block.HashTreeRoot()
+	require.NoError(b, err)
+	bs := &ethpb.BeaconState{FinalizedCheckpoint: &ethpb.Checkpoint{Root: make([]byte, 32)}, CurrentJustifiedCheckpoint: &ethpb.Checkpoint{Root: make([]byte, 32)}}
+	beaconState, err := v1.InitializeFromProto(bs)
+	require.NoError(b, err)
+	wsb, err := wrapper.WrappedSignedBeaconBlock(blk)
+	require.NoError(b, err)
+	require.NoError(b, s.insertBlockAndAttestationsToForkChoiceStore(ctx, wsb.Block(), r, beaconState))
+
+	b.ResetTimer()
+	for i := 0; i < b.N; i++ {
+		require.Equal(b, true, s.cfg.ForkChoiceStore.HasNode(r), "Block is not in fork choice store")
+	}
+}
+func BenchmarkHasBlockForkChoiceStore_DoublyLinkedTree(b *testing.B) {
+	ctx := context.Background()
+	beaconDB := testDB.SetupDB(b)
+	s := &Service{
+		cfg:   &config{ForkChoiceStore: doublylinkedtree.New(0, 0), BeaconDB: beaconDB},
+		store: &store.Store{},
+	}
+	s.store.SetFinalizedCheckpt(&ethpb.Checkpoint{Epoch: 0, Root: params.BeaconConfig().ZeroHash[:]})
 	block := &ethpb.SignedBeaconBlock{Block: &ethpb.BeaconBlock{Body: &ethpb.BeaconBlockBody{}}}
 	r, err := block.Block.HashTreeRoot()
 	require.NoError(b, err)
 	bs := &ethpb.BeaconState{FinalizedCheckpoint: &ethpb.Checkpoint{Root: make([]byte, 32)}, CurrentJustifiedCheckpoint: &ethpb.Checkpoint{Root: make([]byte, 32)}}
 	beaconState, err := v1.InitializeFromProto(bs)
 	require.NoError(b, err)
-	require.NoError(b, s.insertBlockAndAttestationsToForkChoiceStore(ctx, wrapper.WrappedPhase0SignedBeaconBlock(block).Block(), r, beaconState))
+	wsb, err := wrapper.WrappedSignedBeaconBlock(block)
+	require.NoError(b, err)
+	require.NoError(b, s.insertBlockAndAttestationsToForkChoiceStore(ctx, wsb.Block(), r, beaconState))
 
 	b.ResetTimer()
 	for i := 0; i < b.N; i++ {

beacon-chain/blockchain/testing/BUILD.bazel

@@ -18,7 +18,7 @@ go_library(
         "//beacon-chain/core/feed/state:go_default_library",
         "//beacon-chain/core/helpers:go_default_library",
         "//beacon-chain/db:go_default_library",
-        "//beacon-chain/forkchoice/protoarray:go_default_library",
+        "//beacon-chain/forkchoice:go_default_library",
         "//beacon-chain/state:go_default_library",
         "//config/fieldparams:go_default_library",
         "//config/params:go_default_library",

beacon-chain/blockchain/testing/mock.go

@@ -18,7 +18,7 @@ import (
 	statefeed "github.com/prysmaticlabs/prysm/beacon-chain/core/feed/state"
 	"github.com/prysmaticlabs/prysm/beacon-chain/core/helpers"
 	"github.com/prysmaticlabs/prysm/beacon-chain/db"
-	"github.com/prysmaticlabs/prysm/beacon-chain/forkchoice/protoarray"
+	"github.com/prysmaticlabs/prysm/beacon-chain/forkchoice"
 	"github.com/prysmaticlabs/prysm/beacon-chain/state"
 	fieldparams "github.com/prysmaticlabs/prysm/config/fieldparams"
 	"github.com/prysmaticlabs/prysm/config/params"
@@ -41,7 +41,6 @@ type ChainService struct {
 	PreviousJustifiedCheckPoint *ethpb.Checkpoint
 	Slot                        *types.Slot // Pointer because 0 is a useful value, so checking against it can be incorrect.
 	Balance                     *precompute.Balance
-	ForkChoiceStore             *protoarray.Store
 	CanonicalRoots              map[[32]byte]bool
 	Fork                        *ethpb.Fork
 	ETH1Data                    *ethpb.Eth1Data
@@ -61,6 +60,12 @@ type ChainService struct {
 	SyncContributionProofDomain []byte
 	SyncCommitteePubkeys        [][]byte
 	Genesis                     time.Time
+	ForkChoiceStore             forkchoice.ForkChoicer
+}
+
+// ForkChoicer mocks the same method in the chain service
+func (s *ChainService) ForkChoicer() forkchoice.ForkChoicer {
+	return s.ForkChoiceStore
 }
 
 // StateNotifier mocks the same method in the chain service.
@@ -320,11 +325,6 @@ func (s *ChainService) HeadETH1Data() *ethpb.Eth1Data {
 	return s.ETH1Data
 }
 
-// ProtoArrayStore mocks the same method in the chain service.
-func (s *ChainService) ProtoArrayStore() *protoarray.Store {
-	return s.ForkChoiceStore
-}
-
 // GenesisTime mocks the same method in the chain service.
 func (s *ChainService) GenesisTime() time.Time {
 	return s.Genesis
@@ -447,6 +447,6 @@ func (s *ChainService) IsOptimistic(_ context.Context) (bool, error) {
 }
 
 // IsOptimisticForRoot mocks the same method in the chain service.
-func (s *ChainService) IsOptimisticForRoot(_ context.Context, _ [32]byte, _ types.Slot) (bool, error) {
-	return false, nil
+func (s *ChainService) IsOptimisticForRoot(_ context.Context, _ [32]byte) (bool, error) {
+	return s.Optimistic, nil
 }

beacon-chain/blockchain/weak_subjectivity_checks.go

@@ -36,6 +36,7 @@ func NewWeakSubjectivityVerifier(wsc *ethpb.Checkpoint, db weakSubjectivityDB) (
 	// 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{
 			enabled: false,
 		}, nil
@@ -79,15 +80,17 @@ func (v *WeakSubjectivityVerifier) VerifyWeakSubjectivity(ctx context.Context, f
 	if !v.db.HasBlock(ctx, v.root) {
 		return errors.Wrap(errWSBlockNotFound, fmt.Sprintf("missing root %#x", v.root))
 	}
-	filter := filters.NewFilter().SetStartSlot(v.slot).SetEndSlot(v.slot + params.BeaconConfig().SlotsPerEpoch)
+	endSlot := v.slot + params.BeaconConfig().SlotsPerEpoch
+	filter := filters.NewFilter().SetStartSlot(v.slot).SetEndSlot(endSlot)
 	// A node should have the weak subjectivity block corresponds to the correct epoch in the DB.
+	log.Infof("Searching block roots for weak subjectivity root=%#x, between slots %d-%d", v.root, v.slot, endSlot)
 	roots, err := v.db.BlockRoots(ctx, filter)
 	if err != nil {
 		return errors.Wrap(err, "error while retrieving block roots to verify weak subjectivity")
 	}
 	for _, root := range roots {
 		if v.root == root {
-			log.Info("Weak subjectivity check has passed")
+			log.Info("Weak subjectivity check has passed!!")
 			v.verified = true
 			return nil
 		}

beacon-chain/blockchain/weak_subjectivity_checks_test.go

@@ -14,58 +14,65 @@ import (
 	"github.com/prysmaticlabs/prysm/proto/prysm/v1alpha1/wrapper"
 	"github.com/prysmaticlabs/prysm/testing/require"
 	"github.com/prysmaticlabs/prysm/testing/util"
+	"github.com/prysmaticlabs/prysm/time/slots"
 )
 
 func TestService_VerifyWeakSubjectivityRoot(t *testing.T) {
 	beaconDB := testDB.SetupDB(t)
 
 	b := util.NewBeaconBlock()
-	b.Block.Slot = 32
-	require.NoError(t, beaconDB.SaveBlock(context.Background(), wrapper.WrappedPhase0SignedBeaconBlock(b)))
+	b.Block.Slot = 1792480
+	wsb, err := wrapper.WrappedSignedBeaconBlock(b)
+	require.NoError(t, err)
+	require.NoError(t, beaconDB.SaveBlock(context.Background(), wsb))
 	r, err := b.Block.HashTreeRoot()
 	require.NoError(t, err)
+
+	blockEpoch := slots.ToEpoch(b.Block.Slot)
 	tests := []struct {
 		wsVerified     bool
+		disabled       bool
 		wantErr        error
 		checkpt        *ethpb.Checkpoint
 		finalizedEpoch types.Epoch
 		name           string
 	}{
 		{
-			name: "nil root and epoch",
-		},
-		{
-			name:           "already verified",
-			checkpt:        &ethpb.Checkpoint{Epoch: 2},
-			finalizedEpoch: 2,
-			wsVerified:     true,
+			name:     "nil root and epoch",
+			disabled: true,
 		},
 		{
 			name:           "not yet to verify, ws epoch higher than finalized epoch",
-			checkpt:        &ethpb.Checkpoint{Epoch: 2},
-			finalizedEpoch: 1,
+			checkpt:        &ethpb.Checkpoint{Root: bytesutil.PadTo([]byte{'a'}, 32), Epoch: blockEpoch},
+			finalizedEpoch: blockEpoch - 1,
 		},
 		{
 			name:           "can't find the block in DB",
 			checkpt:        &ethpb.Checkpoint{Root: bytesutil.PadTo([]byte{'a'}, fieldparams.RootLength), Epoch: 1},
-			finalizedEpoch: 3,
+			finalizedEpoch: blockEpoch + 1,
 			wantErr:        errWSBlockNotFound,
 		},
 		{
 			name:           "can't find the block corresponds to ws epoch in DB",
-			checkpt:        &ethpb.Checkpoint{Root: r[:], Epoch: 2}, // Root belongs in epoch 1.
-			finalizedEpoch: 3,
+			checkpt:        &ethpb.Checkpoint{Root: r[:], Epoch: blockEpoch - 2}, // Root belongs in epoch 1.
+			finalizedEpoch: blockEpoch - 1,
 			wantErr:        errWSBlockNotFoundInEpoch,
 		},
 		{
 			name:           "can verify and pass",
-			checkpt:        &ethpb.Checkpoint{Root: r[:], Epoch: 1},
-			finalizedEpoch: 3,
+			checkpt:        &ethpb.Checkpoint{Root: r[:], Epoch: blockEpoch},
+			finalizedEpoch: blockEpoch + 1,
+		},
+		{
+			name:           "equal epoch",
+			checkpt:        &ethpb.Checkpoint{Root: r[:], Epoch: blockEpoch},
+			finalizedEpoch: blockEpoch,
 		},
 	}
 	for _, tt := range tests {
 		t.Run(tt.name, func(t *testing.T) {
 			wv, err := NewWeakSubjectivityVerifier(tt.checkpt, beaconDB)
+			require.Equal(t, !tt.disabled, wv.enabled)
 			require.NoError(t, err)
 			s := &Service{
 				cfg:        &config{BeaconDB: beaconDB, WeakSubjectivityCheckpt: tt.checkpt},

beacon-chain/cache/active_balance.go

@@ -1,3 +1,4 @@
+//go:build !fuzz
 // +build !fuzz
 
 package cache
@@ -17,10 +18,12 @@ import (
 	"github.com/prysmaticlabs/prysm/config/params"
 )
 
-var (
+const (
 	// maxBalanceCacheSize defines the max number of active balances can cache.
-	maxBalanceCacheSize = uint64(4)
+	maxBalanceCacheSize = int(4)
+)
 
+var (
 	// BalanceCacheMiss tracks the number of balance requests that aren't present in the cache.
 	balanceCacheMiss = promauto.NewCounter(prometheus.CounterOpts{
 		Name: "total_effective_balance_cache_miss",
@@ -42,7 +45,7 @@ type BalanceCache struct {
 // NewEffectiveBalanceCache creates a new effective balance cache for storing/accessing total balance by epoch.
 func NewEffectiveBalanceCache() *BalanceCache {
 	return &BalanceCache{
-		cache: lruwrpr.New(int(maxBalanceCacheSize)),
+		cache: lruwrpr.New(maxBalanceCacheSize),
 	}
 }
 

beacon-chain/cache/active_balance_disabled.go

@@ -1,3 +1,4 @@
+//go:build fuzz
 // +build fuzz
 
 package cache

beacon-chain/cache/committee.go

@@ -1,3 +1,4 @@
+//go:build !fuzz
 // +build !fuzz
 
 package cache
@@ -19,11 +20,13 @@ import (
 	mathutil "github.com/prysmaticlabs/prysm/math"
 )
 
-var (
+const (
 	// maxCommitteesCacheSize defines the max number of shuffled committees on per randao basis can cache.
 	// Due to reorgs and long finality, it's good to keep the old cache around for quickly switch over.
-	maxCommitteesCacheSize = uint64(32)
+	maxCommitteesCacheSize = int(32)
+)
 
+var (
 	// CommitteeCacheMiss tracks the number of committee requests that aren't present in the cache.
 	CommitteeCacheMiss = promauto.NewCounter(prometheus.CounterOpts{
 		Name: "committee_cache_miss",
@@ -55,7 +58,7 @@ func committeeKeyFn(obj interface{}) (string, error) {
 // NewCommitteesCache creates a new committee cache for storing/accessing shuffled indices of a committee.
 func NewCommitteesCache() *CommitteeCache {
 	return &CommitteeCache{
-		CommitteeCache: lruwrpr.New(int(maxCommitteesCacheSize)),
+		CommitteeCache: lruwrpr.New(maxCommitteesCacheSize),
 		inProgress:     make(map[string]bool),
 	}
 }

beacon-chain/cache/committee_disabled.go

@@ -1,3 +1,4 @@
+//go:build fuzz
 // +build fuzz
 
 // This file is used in fuzzer builds to bypass global committee caches.

beacon-chain/cache/committee_fuzz_test.go

@@ -33,7 +33,7 @@ func TestCommitteeCache_FuzzCommitteesByEpoch(t *testing.T) {
 		require.NoError(t, err)
 	}
 
-	assert.Equal(t, maxCommitteesCacheSize, uint64(len(cache.CommitteeCache.Keys())), "Incorrect key size")
+	assert.Equal(t, maxCommitteesCacheSize, len(cache.CommitteeCache.Keys()), "Incorrect key size")
 }
 
 func TestCommitteeCache_FuzzActiveIndices(t *testing.T) {
@@ -50,5 +50,5 @@ func TestCommitteeCache_FuzzActiveIndices(t *testing.T) {
 		assert.DeepEqual(t, c.SortedIndices, indices)
 	}
 
-	assert.Equal(t, maxCommitteesCacheSize, uint64(len(cache.CommitteeCache.Keys())), "Incorrect key size")
+	assert.Equal(t, maxCommitteesCacheSize, len(cache.CommitteeCache.Keys()), "Incorrect key size")
 }

beacon-chain/cache/committee_test.go

@@ -102,7 +102,7 @@ func TestCommitteeCache_CanRotate(t *testing.T) {
 	}
 
 	k := cache.CommitteeCache.Keys()
-	assert.Equal(t, maxCommitteesCacheSize, uint64(len(k)))
+	assert.Equal(t, maxCommitteesCacheSize, len(k))
 
 	sort.Slice(k, func(i, j int) bool {
 		return k[i].(string) < k[j].(string)

beacon-chain/cache/proposer_indices.go

@@ -1,3 +1,4 @@
+//go:build !fuzz
 // +build !fuzz
 
 package cache

beacon-chain/cache/proposer_indices_disabled.go

@@ -1,3 +1,4 @@
+//go:build fuzz
 // +build fuzz
 
 // This file is used in fuzzer builds to bypass proposer indices caches.

beacon-chain/cache/subnet_ids.go

@@ -27,7 +27,7 @@ var SubnetIDs = newSubnetIDs()
 func newSubnetIDs() *subnetIDs {
 	// Given a node can calculate committee assignments of current epoch and next epoch.
 	// Max size is set to 2 epoch length.
-	cacheSize := int(params.BeaconConfig().SlotsPerEpoch.Mul(params.BeaconConfig().MaxCommitteesPerSlot * 2))
+	cacheSize := int(params.BeaconConfig().SlotsPerEpoch.Mul(params.BeaconConfig().MaxCommitteesPerSlot * 2)) // lint:ignore uintcast -- constant values that would panic on startup if negative.
 	attesterCache := lruwrpr.New(cacheSize)
 	aggregatorCache := lruwrpr.New(cacheSize)
 	epochDuration := time.Duration(params.BeaconConfig().SlotsPerEpoch.Mul(params.BeaconConfig().SecondsPerSlot))

beacon-chain/cache/sync_committee.go

@@ -1,3 +1,4 @@
+//go:build !fuzz
 // +build !fuzz
 
 package cache

beacon-chain/cache/sync_committee_disabled.go

@@ -1,3 +1,4 @@
+//go:build fuzz
 // +build fuzz
 
 package cache

beacon-chain/core/altair/attestation.go

@@ -104,34 +104,30 @@ func SetParticipationAndRewardProposer(
 	targetEpoch types.Epoch,
 	indices []uint64,
 	participatedFlags map[uint8]bool, totalBalance uint64) (state.BeaconState, error) {
-	var epochParticipation []byte
+	var proposerRewardNumerator uint64
 	currentEpoch := time.CurrentEpoch(beaconState)
-	var err error
+	var stateErr error
 	if targetEpoch == currentEpoch {
-		epochParticipation, err = beaconState.CurrentEpochParticipation()
-		if err != nil {
-			return nil, err
-		}
+		stateErr = beaconState.ModifyCurrentParticipationBits(func(val []byte) ([]byte, error) {
+			propRewardNum, epochParticipation, err := EpochParticipation(beaconState, indices, val, participatedFlags, totalBalance)
+			if err != nil {
+				return nil, err
+			}
+			proposerRewardNumerator = propRewardNum
+			return epochParticipation, nil
+		})
 	} else {
-		epochParticipation, err = beaconState.PreviousEpochParticipation()
-		if err != nil {
-			return nil, err
-		}
+		stateErr = beaconState.ModifyPreviousParticipationBits(func(val []byte) ([]byte, error) {
+			propRewardNum, epochParticipation, err := EpochParticipation(beaconState, indices, val, participatedFlags, totalBalance)
+			if err != nil {
+				return nil, err
+			}
+			proposerRewardNumerator = propRewardNum
+			return epochParticipation, nil
+		})
 	}
-
-	proposerRewardNumerator, epochParticipation, err := EpochParticipation(beaconState, indices, epochParticipation, participatedFlags, totalBalance)
-	if err != nil {
-		return nil, err
-	}
-
-	if targetEpoch == currentEpoch {
-		if err := beaconState.SetCurrentParticipationBits(epochParticipation); err != nil {
-			return nil, err
-		}
-	} else {
-		if err := beaconState.SetPreviousParticipationBits(epochParticipation); err != nil {
-			return nil, err
-		}
+	if stateErr != nil {
+		return nil, stateErr
 	}
 
 	if err := RewardProposer(ctx, beaconState, proposerRewardNumerator); err != nil {

beacon-chain/core/altair/attestation_test.go

@@ -48,7 +48,7 @@ func TestProcessAttestations_InclusionDelayFailure(t *testing.T) {
 		params.BeaconConfig().MinAttestationInclusionDelay,
 		beaconState.Slot(),
 	)
-	wsb, err := wrapper.WrappedAltairSignedBeaconBlock(b)
+	wsb, err := wrapper.WrappedSignedBeaconBlock(b)
 	require.NoError(t, err)
 	_, err = altair.ProcessAttestationsNoVerifySignature(context.Background(), beaconState, wsb)
 	require.ErrorContains(t, want, err)
@@ -79,7 +79,7 @@ func TestProcessAttestations_NeitherCurrentNorPrevEpoch(t *testing.T) {
 		time.PrevEpoch(beaconState),
 		time.CurrentEpoch(beaconState),
 	)
-	wsb, err := wrapper.WrappedAltairSignedBeaconBlock(b)
+	wsb, err := wrapper.WrappedSignedBeaconBlock(b)
 	require.NoError(t, err)
 	_, err = altair.ProcessAttestationsNoVerifySignature(context.Background(), beaconState, wsb)
 	require.ErrorContains(t, want, err)
@@ -108,13 +108,13 @@ func TestProcessAttestations_CurrentEpochFFGDataMismatches(t *testing.T) {
 	require.NoError(t, beaconState.SetCurrentJustifiedCheckpoint(cfc))
 
 	want := "source check point not equal to current justified checkpoint"
-	wsb, err := wrapper.WrappedAltairSignedBeaconBlock(b)
+	wsb, err := wrapper.WrappedSignedBeaconBlock(b)
 	require.NoError(t, err)
 	_, err = altair.ProcessAttestationsNoVerifySignature(context.Background(), beaconState, wsb)
 	require.ErrorContains(t, want, err)
 	b.Block.Body.Attestations[0].Data.Source.Epoch = time.CurrentEpoch(beaconState)
 	b.Block.Body.Attestations[0].Data.Source.Root = []byte{}
-	wsb, err = wrapper.WrappedAltairSignedBeaconBlock(b)
+	wsb, err = wrapper.WrappedSignedBeaconBlock(b)
 	require.NoError(t, err)
 	_, err = altair.ProcessAttestationsNoVerifySignature(context.Background(), beaconState, wsb)
 	require.ErrorContains(t, want, err)
@@ -149,14 +149,14 @@ func TestProcessAttestations_PrevEpochFFGDataMismatches(t *testing.T) {
 	require.NoError(t, beaconState.SetPreviousJustifiedCheckpoint(pfc))
 
 	want := "source check point not equal to previous justified checkpoint"
-	wsb, err := wrapper.WrappedAltairSignedBeaconBlock(b)
+	wsb, err := wrapper.WrappedSignedBeaconBlock(b)
 	require.NoError(t, err)
 	_, err = altair.ProcessAttestationsNoVerifySignature(context.Background(), beaconState, wsb)
 	require.ErrorContains(t, want, err)
 	b.Block.Body.Attestations[0].Data.Source.Epoch = time.PrevEpoch(beaconState)
 	b.Block.Body.Attestations[0].Data.Target.Epoch = time.PrevEpoch(beaconState)
 	b.Block.Body.Attestations[0].Data.Source.Root = []byte{}
-	wsb, err = wrapper.WrappedAltairSignedBeaconBlock(b)
+	wsb, err = wrapper.WrappedSignedBeaconBlock(b)
 	require.NoError(t, err)
 	_, err = altair.ProcessAttestationsNoVerifySignature(context.Background(), beaconState, wsb)
 	require.ErrorContains(t, want, err)
@@ -188,7 +188,7 @@ func TestProcessAttestations_InvalidAggregationBitsLength(t *testing.T) {
 	require.NoError(t, beaconState.SetCurrentJustifiedCheckpoint(cfc))
 
 	expected := "failed to verify aggregation bitfield: wanted participants bitfield length 3, got: 4"
-	wsb, err := wrapper.WrappedAltairSignedBeaconBlock(b)
+	wsb, err := wrapper.WrappedSignedBeaconBlock(b)
 	require.NoError(t, err)
 	_, err = altair.ProcessAttestationsNoVerifySignature(context.Background(), beaconState, wsb)
 	require.ErrorContains(t, expected, err)
@@ -232,7 +232,7 @@ func TestProcessAttestations_OK(t *testing.T) {
 
 	err = beaconState.SetSlot(beaconState.Slot() + params.BeaconConfig().MinAttestationInclusionDelay)
 	require.NoError(t, err)
-	wsb, err := wrapper.WrappedAltairSignedBeaconBlock(block)
+	wsb, err := wrapper.WrappedSignedBeaconBlock(block)
 	require.NoError(t, err)
 	_, err = altair.ProcessAttestationsNoVerifySignature(context.Background(), beaconState, wsb)
 	require.NoError(t, err)
@@ -421,7 +421,7 @@ func TestFuzzProcessAttestationsNoVerify_10000(t *testing.T) {
 		}
 		s, err := stateAltair.InitializeFromProtoUnsafe(state)
 		require.NoError(t, err)
-		wsb, err := wrapper.WrappedAltairSignedBeaconBlock(b)
+		wsb, err := wrapper.WrappedSignedBeaconBlock(b)
 		require.NoError(t, err)
 		r, err := altair.ProcessAttestationsNoVerifySignature(context.Background(), s, wsb)
 		if err != nil && r != nil {

beacon-chain/core/blocks/BUILD.bazel

@@ -45,6 +45,7 @@ go_library(
         "//proto/prysm/v1alpha1/attestation:go_default_library",
         "//proto/prysm/v1alpha1/block:go_default_library",
         "//proto/prysm/v1alpha1/slashings:go_default_library",
+        "//proto/prysm/v1alpha1/wrapper:go_default_library",
         "//runtime/version:go_default_library",
         "//time/slots:go_default_library",
         "@com_github_pkg_errors//:go_default_library",

beacon-chain/core/blocks/block_operations_fuzz_test.go

@@ -42,7 +42,9 @@ func TestFuzzProcessBlockHeader_10000(t *testing.T) {
 
 		s, err := v1.InitializeFromProtoUnsafe(state)
 		require.NoError(t, err)
-		_, err = ProcessBlockHeader(context.Background(), s, wrapper.WrappedPhase0SignedBeaconBlock(block))
+		wsb, err := wrapper.WrappedSignedBeaconBlock(block)
+		require.NoError(t, err)
+		_, err = ProcessBlockHeader(context.Background(), s, wsb)
 		_ = err
 	}
 }
@@ -141,7 +143,9 @@ func TestFuzzProcessRandao_10000(t *testing.T) {
 		fuzzer.Fuzz(b)
 		s, err := v1.InitializeFromProtoUnsafe(state)
 		require.NoError(t, err)
-		r, err := ProcessRandao(context.Background(), s, wrapper.WrappedPhase0SignedBeaconBlock(b))
+		wsb, err := wrapper.WrappedSignedBeaconBlock(b)
+		require.NoError(t, err)
+		r, err := ProcessRandao(context.Background(), s, wsb)
 		if err != nil && r != nil {
 			t.Fatalf("return value should be nil on err. found: %v on error: %v for state: %v and block: %v", r, err, state, b)
 		}
@@ -260,7 +264,9 @@ func TestFuzzProcessAttestationsNoVerify_10000(t *testing.T) {
 		fuzzer.Fuzz(b)
 		s, err := v1.InitializeFromProtoUnsafe(state)
 		require.NoError(t, err)
-		r, err := ProcessAttestationsNoVerifySignature(ctx, s, wrapper.WrappedPhase0SignedBeaconBlock(b))
+		wsb, err := wrapper.WrappedSignedBeaconBlock(b)
+		require.NoError(t, err)
+		r, err := ProcessAttestationsNoVerifySignature(ctx, s, wsb)
 		if err != nil && r != nil {
 			t.Fatalf("return value should be nil on err. found: %v on error: %v for state: %v and block: %v", r, err, state, b)
 		}

beacon-chain/core/blocks/deposit.go

@@ -225,7 +225,7 @@ func verifyDeposit(beaconState state.ReadOnlyBeaconState, deposit *ethpb.Deposit
 	if ok := trie.VerifyMerkleProofWithDepth(
 		receiptRoot,
 		leaf[:],
-		int(beaconState.Eth1DepositIndex()),
+		beaconState.Eth1DepositIndex(),
 		deposit.Proof,
 		params.BeaconConfig().DepositContractTreeDepth,
 	); !ok {

beacon-chain/core/blocks/header_test.go

@@ -68,7 +68,9 @@ func TestProcessBlockHeader_ImproperBlockSlot(t *testing.T) {
 	err = state.UpdateValidatorAtIndex(proposerIdx, validators[proposerIdx])
 	require.NoError(t, err)
 
-	_, err = blocks.ProcessBlockHeader(context.Background(), state, wrapper.WrappedPhase0SignedBeaconBlock(block))
+	wsb, err := wrapper.WrappedSignedBeaconBlock(block)
+	require.NoError(t, err)
+	_, err = blocks.ProcessBlockHeader(context.Background(), state, wsb)
 	assert.ErrorContains(t, "block.Slot 10 must be greater than state.LatestBlockHeader.Slot 10", err)
 }
 
@@ -94,7 +96,9 @@ func TestProcessBlockHeader_WrongProposerSig(t *testing.T) {
 	block.Signature, err = signing.ComputeDomainAndSign(beaconState, 0, block.Block, params.BeaconConfig().DomainBeaconProposer, privKeys[proposerIdx+1])
 	require.NoError(t, err)
 
-	_, err = blocks.ProcessBlockHeader(context.Background(), beaconState, wrapper.WrappedPhase0SignedBeaconBlock(block))
+	wsb, err := wrapper.WrappedSignedBeaconBlock(block)
+	require.NoError(t, err)
+	_, err = blocks.ProcessBlockHeader(context.Background(), beaconState, wsb)
 	want := "signature did not verify"
 	assert.ErrorContains(t, want, err)
 }
@@ -136,7 +140,9 @@ func TestProcessBlockHeader_DifferentSlots(t *testing.T) {
 		Signature: blockSig,
 	})
 
-	_, err = blocks.ProcessBlockHeader(context.Background(), state, wrapper.WrappedPhase0SignedBeaconBlock(block))
+	wsb, err := wrapper.WrappedSignedBeaconBlock(block)
+	require.NoError(t, err)
+	_, err = blocks.ProcessBlockHeader(context.Background(), state, wsb)
 	want := "is different than block slot"
 	assert.ErrorContains(t, want, err)
 }
@@ -175,7 +181,9 @@ func TestProcessBlockHeader_PreviousBlockRootNotSignedRoot(t *testing.T) {
 	block.Block.ParentRoot = bytesutil.PadTo([]byte{'A'}, 32)
 	block.Signature = blockSig
 
-	_, err = blocks.ProcessBlockHeader(context.Background(), state, wrapper.WrappedPhase0SignedBeaconBlock(block))
+	wsb, err := wrapper.WrappedSignedBeaconBlock(block)
+	require.NoError(t, err)
+	_, err = blocks.ProcessBlockHeader(context.Background(), state, wsb)
 	want := "does not match"
 	assert.ErrorContains(t, want, err)
 }
@@ -217,7 +225,9 @@ func TestProcessBlockHeader_SlashedProposer(t *testing.T) {
 	block.Block.ParentRoot = parentRoot[:]
 	block.Signature = blockSig
 
-	_, err = blocks.ProcessBlockHeader(context.Background(), state, wrapper.WrappedPhase0SignedBeaconBlock(block))
+	wsb, err := wrapper.WrappedSignedBeaconBlock(block)
+	require.NoError(t, err)
+	_, err = blocks.ProcessBlockHeader(context.Background(), state, wsb)
 	want := "was previously slashed"
 	assert.ErrorContains(t, want, err)
 }
@@ -266,7 +276,9 @@ func TestProcessBlockHeader_OK(t *testing.T) {
 	err = state.UpdateValidatorAtIndex(proposerIdx, validators[proposerIdx])
 	require.NoError(t, err)
 
-	newState, err := blocks.ProcessBlockHeader(context.Background(), state, wrapper.WrappedPhase0SignedBeaconBlock(block))
+	wsb, err := wrapper.WrappedSignedBeaconBlock(block)
+	require.NoError(t, err)
+	newState, err := blocks.ProcessBlockHeader(context.Background(), state, wsb)
 	require.NoError(t, err, "Failed to process block header got")
 	var zeroHash [32]byte
 	nsh := newState.LatestBlockHeader()

beacon-chain/core/blocks/payload.go

@@ -2,7 +2,6 @@ package blocks
 
 import (
 	"bytes"
-	"strings"
 
 	"github.com/pkg/errors"
 	"github.com/prysmaticlabs/prysm/beacon-chain/core/helpers"
@@ -14,74 +13,96 @@ import (
 	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"
+	"github.com/prysmaticlabs/prysm/runtime/version"
 	"github.com/prysmaticlabs/prysm/time/slots"
 )
 
-// MergeTransitionComplete returns true if the transition to Bellatrix has completed.
+// IsMergeTransitionComplete returns true if the transition to Bellatrix has completed.
 // Meaning the payload header in beacon state is not `ExecutionPayloadHeader()` (i.e. not empty).
 //
 // Spec code:
 // def is_merge_transition_complete(state: BeaconState) -> bool:
 //    return state.latest_execution_payload_header != ExecutionPayloadHeader()
-func MergeTransitionComplete(st state.BeaconState) (bool, error) {
+func IsMergeTransitionComplete(st state.BeaconState) (bool, error) {
+	if st == nil {
+		return false, errors.New("nil state")
+	}
+	if IsPreBellatrixVersion(st.Version()) {
+		return false, nil
+	}
 	h, err := st.LatestExecutionPayloadHeader()
 	if err != nil {
 		return false, err
 	}
-
 	return !isEmptyHeader(h), nil
 }
 
-// MergeTransitionBlock returns true if the input block is the terminal merge block.
-// Meaning the header in beacon state is  `ExecutionPayloadHeader()` (i.e. empty).
-// And the input block has a non-empty header.
-//
-// Spec code:
-// def is_merge_transition_block(state: BeaconState, body: BeaconBlockBody) -> bool:
-//    return not is_merge_transition_complete(state) and body.execution_payload != ExecutionPayload()
-func MergeTransitionBlock(st state.BeaconState, body block.BeaconBlockBody) (bool, error) {
-	mergeComplete, err := MergeTransitionComplete(st)
-	if err != nil {
-		return false, err
+// IsMergeTransitionBlockUsingPreStatePayloadHeader returns true if the input block is the terminal merge block.
+// Terminal merge block must be associated with an empty payload header.
+// This assumes the header `h` is referenced as the parent state for block body `body.
+func IsMergeTransitionBlockUsingPreStatePayloadHeader(h *ethpb.ExecutionPayloadHeader, body block.BeaconBlockBody) (bool, error) {
+	if h == nil || body == nil {
+		return false, errors.New("nil header or block body")
 	}
-	if mergeComplete {
-		return false, err
+	if !isEmptyHeader(h) {
+		return false, nil
 	}
-
-	return ExecutionBlock(body)
+	return IsExecutionBlock(body)
 }
 
-// ExecutionBlock returns whether the block has a non-empty ExecutionPayload.
+// IsExecutionBlock returns whether the block has a non-empty ExecutionPayload.
 //
 // Spec code:
 // def is_execution_block(block: BeaconBlock) -> bool:
 //     return block.body.execution_payload != ExecutionPayload()
-func ExecutionBlock(body block.BeaconBlockBody) (bool, error) {
+func IsExecutionBlock(body block.BeaconBlockBody) (bool, error) {
+	if body == nil {
+		return false, errors.New("nil block body")
+	}
 	payload, err := body.ExecutionPayload()
-	if err != nil {
-		if strings.HasPrefix(err.Error(), "ExecutionPayload is not supported in") {
-			return false, nil
-		}
+	switch {
+	case errors.Is(err, wrapper.ErrUnsupportedField):
+		return false, nil
+	case err != nil:
 		return false, err
+	default:
 	}
 	return !isEmptyPayload(payload), nil
 }
 
-// ExecutionEnabled returns true if the beacon chain can begin executing.
+// IsExecutionEnabled returns true if the beacon chain can begin executing.
 // Meaning the payload header is beacon state is non-empty or the payload in block body is non-empty.
 //
 // Spec code:
 // def is_execution_enabled(state: BeaconState, body: BeaconBlockBody) -> bool:
 //    return is_merge_block(state, body) or is_merge_complete(state)
-func ExecutionEnabled(st state.BeaconState, body block.BeaconBlockBody) (bool, error) {
-	mergeBlock, err := MergeTransitionBlock(st, body)
+func IsExecutionEnabled(st state.BeaconState, body block.BeaconBlockBody) (bool, error) {
+	if st == nil || body == nil {
+		return false, errors.New("nil state or block body")
+	}
+	if IsPreBellatrixVersion(st.Version()) {
+		return false, nil
+	}
+	header, err := st.LatestExecutionPayloadHeader()
 	if err != nil {
 		return false, err
 	}
-	if mergeBlock {
+	return IsExecutionEnabledUsingHeader(header, body)
+}
+
+// IsExecutionEnabledUsingHeader returns true if the execution is enabled using post processed payload header and block body.
+// This is an optimized version of IsExecutionEnabled where beacon state is not required as an argument.
+func IsExecutionEnabledUsingHeader(header *ethpb.ExecutionPayloadHeader, body block.BeaconBlockBody) (bool, error) {
+	if !isEmptyHeader(header) {
 		return true, nil
 	}
-	return MergeTransitionComplete(st)
+	return IsExecutionBlock(body)
+}
+
+// IsPreBellatrixVersion returns true if input version is before bellatrix fork.
+func IsPreBellatrixVersion(v int) bool {
+	return v < version.Bellatrix
 }
 
 // ValidatePayloadWhenMergeCompletes validates if payload is valid versus input beacon state.
@@ -92,7 +113,7 @@ func ExecutionEnabled(st state.BeaconState, body block.BeaconBlockBody) (bool, e
 //    if is_merge_complete(state):
 //        assert payload.parent_hash == state.latest_execution_payload_header.block_hash
 func ValidatePayloadWhenMergeCompletes(st state.BeaconState, payload *enginev1.ExecutionPayload) error {
-	complete, err := MergeTransitionComplete(st)
+	complete, err := IsMergeTransitionComplete(st)
 	if err != nil {
 		return err
 	}
@@ -214,6 +235,9 @@ func PayloadToHeader(payload *enginev1.ExecutionPayload) (*ethpb.ExecutionPayloa
 }
 
 func isEmptyPayload(p *enginev1.ExecutionPayload) bool {
+	if p == nil {
+		return true
+	}
 	if !bytes.Equal(p.ParentHash, make([]byte, fieldparams.RootLength)) {
 		return false
 	}

beacon-chain/core/blocks/payload_test.go

@@ -18,7 +18,7 @@ import (
 	"github.com/prysmaticlabs/prysm/time/slots"
 )
 
-func Test_MergeComplete(t *testing.T) {
+func Test_IsMergeComplete(t *testing.T) {
 	tests := []struct {
 		name    string
 		payload *ethpb.ExecutionPayloadHeader
@@ -160,7 +160,7 @@ func Test_MergeComplete(t *testing.T) {
 		t.Run(tt.name, func(t *testing.T) {
 			st, _ := util.DeterministicGenesisStateBellatrix(t, 1)
 			require.NoError(t, st.SetLatestExecutionPayloadHeader(tt.payload))
-			got, err := blocks.MergeTransitionComplete(st)
+			got, err := blocks.IsMergeTransitionComplete(st)
 			require.NoError(t, err)
 			if got != tt.want {
 				t.Errorf("mergeComplete() got = %v, want %v", got, tt.want)
@@ -169,7 +169,7 @@ func Test_MergeComplete(t *testing.T) {
 	}
 }
 
-func Test_MergeBlock(t *testing.T) {
+func Test_IsMergeTransitionBlockUsingPayloadHeader(t *testing.T) {
 	tests := []struct {
 		name    string
 		payload *enginev1.ExecutionPayload
@@ -335,13 +335,11 @@ func Test_MergeBlock(t *testing.T) {
 	}
 	for _, tt := range tests {
 		t.Run(tt.name, func(t *testing.T) {
-			st, _ := util.DeterministicGenesisStateBellatrix(t, 1)
-			require.NoError(t, st.SetLatestExecutionPayloadHeader(tt.header))
 			blk := util.NewBeaconBlockBellatrix()
 			blk.Block.Body.ExecutionPayload = tt.payload
 			body, err := wrapper.WrappedBellatrixBeaconBlockBody(blk.Block.Body)
 			require.NoError(t, err)
-			got, err := blocks.MergeTransitionBlock(st, body)
+			got, err := blocks.IsMergeTransitionBlockUsingPreStatePayloadHeader(tt.header, body)
 			require.NoError(t, err)
 			if got != tt.want {
 				t.Errorf("MergeTransitionBlock() got = %v, want %v", got, tt.want)
@@ -377,20 +375,28 @@ func Test_IsExecutionBlock(t *testing.T) {
 			blk.Block.Body.ExecutionPayload = tt.payload
 			wrappedBlock, err := wrapper.WrappedBellatrixBeaconBlock(blk.Block)
 			require.NoError(t, err)
-			got, err := blocks.ExecutionBlock(wrappedBlock.Body())
+			got, err := blocks.IsExecutionBlock(wrappedBlock.Body())
 			require.NoError(t, err)
 			require.Equal(t, tt.want, got)
 		})
 	}
 }
 
-func Test_ExecutionEnabled(t *testing.T) {
+func Test_IsExecutionEnabled(t *testing.T) {
 	tests := []struct {
-		name    string
-		payload *enginev1.ExecutionPayload
-		header  *ethpb.ExecutionPayloadHeader
-		want    bool
+		name        string
+		payload     *enginev1.ExecutionPayload
+		header      *ethpb.ExecutionPayloadHeader
+		useAltairSt bool
+		want        bool
 	}{
+		{
+			name:        "use older than bellatrix state",
+			payload:     emptyPayload(),
+			header:      emptyPayloadHeader(),
+			useAltairSt: true,
+			want:        false,
+		},
 		{
 			name:    "empty header, empty payload",
 			payload: emptyPayload(),
@@ -440,10 +446,76 @@ func Test_ExecutionEnabled(t *testing.T) {
 			blk.Block.Body.ExecutionPayload = tt.payload
 			body, err := wrapper.WrappedBellatrixBeaconBlockBody(blk.Block.Body)
 			require.NoError(t, err)
-			got, err := blocks.ExecutionEnabled(st, body)
+			if tt.useAltairSt {
+				st, _ = util.DeterministicGenesisStateAltair(t, 1)
+			}
+			got, err := blocks.IsExecutionEnabled(st, body)
 			require.NoError(t, err)
 			if got != tt.want {
-				t.Errorf("ExecutionEnabled() got = %v, want %v", got, tt.want)
+				t.Errorf("IsExecutionEnabled() got = %v, want %v", got, tt.want)
+			}
+		})
+	}
+}
+
+func Test_IsExecutionEnabledUsingHeader(t *testing.T) {
+	tests := []struct {
+		name    string
+		payload *enginev1.ExecutionPayload
+		header  *ethpb.ExecutionPayloadHeader
+		want    bool
+	}{
+		{
+			name:    "empty header, empty payload",
+			payload: emptyPayload(),
+			header:  emptyPayloadHeader(),
+			want:    false,
+		},
+		{
+			name:    "non-empty header, empty payload",
+			payload: emptyPayload(),
+			header: func() *ethpb.ExecutionPayloadHeader {
+				h := emptyPayloadHeader()
+				h.ParentHash = bytesutil.PadTo([]byte{'a'}, fieldparams.RootLength)
+				return h
+			}(),
+			want: true,
+		},
+		{
+			name:   "empty header, non-empty payload",
+			header: emptyPayloadHeader(),
+			payload: func() *enginev1.ExecutionPayload {
+				p := emptyPayload()
+				p.Timestamp = 1
+				return p
+			}(),
+			want: true,
+		},
+		{
+			name: "non-empty header, non-empty payload",
+			header: func() *ethpb.ExecutionPayloadHeader {
+				h := emptyPayloadHeader()
+				h.ParentHash = bytesutil.PadTo([]byte{'a'}, fieldparams.RootLength)
+				return h
+			}(),
+			payload: func() *enginev1.ExecutionPayload {
+				p := emptyPayload()
+				p.Timestamp = 1
+				return p
+			}(),
+			want: true,
+		},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			blk := util.NewBeaconBlockBellatrix()
+			blk.Block.Body.ExecutionPayload = tt.payload
+			body, err := wrapper.WrappedBellatrixBeaconBlockBody(blk.Block.Body)
+			require.NoError(t, err)
+			got, err := blocks.IsExecutionEnabledUsingHeader(tt.header, body)
+			require.NoError(t, err)
+			if got != tt.want {
+				t.Errorf("IsExecutionEnabled() got = %v, want %v", got, tt.want)
 			}
 		})
 	}
@@ -651,7 +723,7 @@ func BenchmarkBellatrixComplete(b *testing.B) {
 
 	b.ResetTimer()
 	for i := 0; i < b.N; i++ {
-		_, err := blocks.MergeTransitionComplete(st)
+		_, err := blocks.IsMergeTransitionComplete(st)
 		require.NoError(b, err)
 	}
 }

beacon-chain/core/blocks/randao_test.go

@@ -40,7 +40,9 @@ func TestProcessRandao_IncorrectProposerFailsVerification(t *testing.T) {
 	}
 
 	want := "block randao: signature did not verify"
-	_, err = blocks.ProcessRandao(context.Background(), beaconState, wrapper.WrappedPhase0SignedBeaconBlock(b))
+	wsb, err := wrapper.WrappedSignedBeaconBlock(b)
+	require.NoError(t, err)
+	_, err = blocks.ProcessRandao(context.Background(), beaconState, wsb)
 	assert.ErrorContains(t, want, err)
 }
 
@@ -57,11 +59,12 @@ func TestProcessRandao_SignatureVerifiesAndUpdatesLatestStateMixes(t *testing.T)
 			RandaoReveal: epochSignature,
 		},
 	}
-
+	wsb, err := wrapper.WrappedSignedBeaconBlock(b)
+	require.NoError(t, err)
 	newState, err := blocks.ProcessRandao(
 		context.Background(),
 		beaconState,
-		wrapper.WrappedPhase0SignedBeaconBlock(b),
+		wsb,
 	)
 	require.NoError(t, err, "Unexpected error processing block randao")
 	currentEpoch := time.CurrentEpoch(beaconState)

beacon-chain/core/blocks/signature_test.go

@@ -83,7 +83,7 @@ func TestVerifyBlockSignatureUsingCurrentFork(t *testing.T) {
 	assert.NoError(t, err)
 	sig := keys[0].Sign(rt[:]).Marshal()
 	altairBlk.Signature = sig
-	wsb, err := wrapper.WrappedAltairSignedBeaconBlock(altairBlk)
+	wsb, err := wrapper.WrappedSignedBeaconBlock(altairBlk)
 	require.NoError(t, err)
 	assert.NoError(t, blocks.VerifyBlockSignatureUsingCurrentFork(bState, wsb))
 }

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

@@ -13,5 +13,6 @@ const (
 
 // ReceivedBlockData is the data sent with ReceivedBlock events.
 type ReceivedBlockData struct {
-	SignedBlock block.SignedBeaconBlock
+	SignedBlock  block.SignedBeaconBlock
+	IsOptimistic bool
 }

beacon-chain/core/helpers/BUILD.bazel

@@ -15,29 +15,12 @@ go_library(
         "weak_subjectivity.go",
     ],
     importpath = "github.com/prysmaticlabs/prysm/beacon-chain/core/helpers",
-    visibility = [
-        "//beacon-chain:__subpackages__",
-        "//cmd/beacon-chain:__subpackages__",
-        "//contracts/deposit:__pkg__",
-        "//crypto/keystore:__pkg__",
-        "//network/forks:__pkg__",
-        "//proto/prysm/v1alpha1:__subpackages__",
-        "//proto/prysm/v1alpha1/attestation:__pkg__",
-        "//runtime/interop:__pkg__",
-        "//slasher:__subpackages__",
-        "//testing/altair:__pkg__",
-        "//testing/benchmark/benchmark_files:__subpackages__",
-        "//testing/endtoend/evaluators:__pkg__",
-        "//testing/slasher/simulator:__pkg__",
-        "//testing/spectest:__subpackages__",
-        "//testing/util:__pkg__",
-        "//tools:__subpackages__",
-        "//validator:__subpackages__",
-    ],
+    visibility = ["//visibility:public"],
     deps = [
         "//beacon-chain/cache:go_default_library",
         "//beacon-chain/core/time:go_default_library",
         "//beacon-chain/state:go_default_library",
+        "//config/fieldparams:go_default_library",
         "//config/params:go_default_library",
         "//container/slice:go_default_library",
         "//container/trie:go_default_library",

beacon-chain/core/helpers/block.go

@@ -11,18 +11,22 @@ import (
 	"github.com/prysmaticlabs/prysm/time/slots"
 )
 
+var ErrNilSignedBeaconBlock = errors.New("signed beacon block can't be nil")
+var ErrNilBeaconBlock = errors.New("beacon block can't be nil")
+var ErrNilBeaconBlockBody = errors.New("beacon block body can't be nil")
+
 // BeaconBlockIsNil checks if any composite field of input signed beacon block is nil.
 // Access to these nil fields will result in run time panic,
 // it is recommended to run these checks as first line of defense.
 func BeaconBlockIsNil(b block.SignedBeaconBlock) error {
 	if b == nil || b.IsNil() {
-		return errors.New("signed beacon block can't be nil")
+		return ErrNilSignedBeaconBlock
 	}
 	if b.Block().IsNil() {
-		return errors.New("beacon block can't be nil")
+		return ErrNilBeaconBlock
 	}
 	if b.Block().Body().IsNil() {
-		return errors.New("beacon block body can't be nil")
+		return ErrNilBeaconBlockBody
 	}
 	return nil
 }

beacon-chain/core/helpers/weak_subjectivity.go

@@ -1,7 +1,6 @@
 package helpers
 
 import (
-	"bytes"
 	"context"
 	"encoding/hex"
 	"errors"
@@ -12,9 +11,11 @@ import (
 	types "github.com/prysmaticlabs/eth2-types"
 	"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/config/params"
+	"github.com/prysmaticlabs/prysm/encoding/bytesutil"
 	"github.com/prysmaticlabs/prysm/math"
-	eth "github.com/prysmaticlabs/prysm/proto/prysm/v1alpha1"
+	v1alpha1 "github.com/prysmaticlabs/prysm/proto/prysm/v1alpha1"
 	"github.com/prysmaticlabs/prysm/time/slots"
 )
 
@@ -54,9 +55,9 @@ import (
 //        )
 //
 //    return ws_period
-func ComputeWeakSubjectivityPeriod(ctx context.Context, st state.ReadOnlyBeaconState) (types.Epoch, error) {
+func ComputeWeakSubjectivityPeriod(ctx context.Context, st state.ReadOnlyBeaconState, cfg *params.BeaconChainConfig) (types.Epoch, error) {
 	// Weak subjectivity period cannot be smaller than withdrawal delay.
-	wsp := uint64(params.BeaconConfig().MinValidatorWithdrawabilityDelay)
+	wsp := uint64(cfg.MinValidatorWithdrawabilityDelay)
 
 	// Cardinality of active validator set.
 	N, err := ActiveValidatorCount(ctx, st, time.CurrentEpoch(st))
@@ -72,10 +73,10 @@ func ComputeWeakSubjectivityPeriod(ctx context.Context, st state.ReadOnlyBeaconS
 	if err != nil {
 		return 0, fmt.Errorf("cannot find total active balance of validators: %w", err)
 	}
-	t = t / N / params.BeaconConfig().GweiPerEth
+	t = t / N / cfg.GweiPerEth
 
 	// Maximum effective balance per validator.
-	T := params.BeaconConfig().MaxEffectiveBalance / params.BeaconConfig().GweiPerEth
+	T := cfg.MaxEffectiveBalance / cfg.GweiPerEth
 
 	// Validator churn limit.
 	delta, err := ValidatorChurnLimit(N)
@@ -84,14 +85,14 @@ func ComputeWeakSubjectivityPeriod(ctx context.Context, st state.ReadOnlyBeaconS
 	}
 
 	// Balance top-ups.
-	Delta := uint64(params.BeaconConfig().SlotsPerEpoch.Mul(params.BeaconConfig().MaxDeposits))
+	Delta := uint64(cfg.SlotsPerEpoch.Mul(cfg.MaxDeposits))
 
 	if delta == 0 || Delta == 0 {
 		return 0, errors.New("either validator churn limit or balance top-ups is zero")
 	}
 
 	// Safety decay, maximum tolerable loss of safety margin of FFG finality.
-	D := params.BeaconConfig().SafetyDecay
+	D := cfg.SafetyDecay
 
 	if T*(200+3*D) < t*(200+12*D) {
 		epochsForValidatorSetChurn := N * (t*(200+12*D) - T*(200+3*D)) / (600 * delta * (2*t + T))
@@ -122,24 +123,24 @@ func ComputeWeakSubjectivityPeriod(ctx context.Context, st state.ReadOnlyBeaconS
 //    current_epoch = compute_epoch_at_slot(get_current_slot(store))
 //    return current_epoch <= ws_state_epoch + ws_period
 func IsWithinWeakSubjectivityPeriod(
-	ctx context.Context, currentEpoch types.Epoch, wsState state.ReadOnlyBeaconState, wsCheckpoint *eth.WeakSubjectivityCheckpoint) (bool, error) {
+	ctx context.Context, currentEpoch types.Epoch, wsState state.ReadOnlyBeaconState, wsStateRoot [fieldparams.RootLength]byte, wsEpoch types.Epoch, cfg *params.BeaconChainConfig) (bool, error) {
 	// Make sure that incoming objects are not nil.
-	if wsState == nil || wsState.IsNil() || wsState.LatestBlockHeader() == nil || wsCheckpoint == nil {
+	if wsState == nil || wsState.IsNil() || wsState.LatestBlockHeader() == nil {
 		return false, errors.New("invalid weak subjectivity state or checkpoint")
 	}
 
 	// Assert that state and checkpoint have the same root and epoch.
-	if !bytes.Equal(wsState.LatestBlockHeader().StateRoot, wsCheckpoint.StateRoot) {
+	if bytesutil.ToBytes32(wsState.LatestBlockHeader().StateRoot) != wsStateRoot {
 		return false, fmt.Errorf("state (%#x) and checkpoint (%#x) roots do not match",
-			wsState.LatestBlockHeader().StateRoot, wsCheckpoint.StateRoot)
+			wsState.LatestBlockHeader().StateRoot, wsStateRoot)
 	}
-	if slots.ToEpoch(wsState.Slot()) != wsCheckpoint.Epoch {
+	if slots.ToEpoch(wsState.Slot()) != wsEpoch {
 		return false, fmt.Errorf("state (%v) and checkpoint (%v) epochs do not match",
-			slots.ToEpoch(wsState.Slot()), wsCheckpoint.Epoch)
+			slots.ToEpoch(wsState.Slot()), wsEpoch)
 	}
 
 	// Compare given epoch to state epoch + weak subjectivity period.
-	wsPeriod, err := ComputeWeakSubjectivityPeriod(ctx, wsState)
+	wsPeriod, err := ComputeWeakSubjectivityPeriod(ctx, wsState, cfg)
 	if err != nil {
 		return false, fmt.Errorf("cannot compute weak subjectivity period: %w", err)
 	}
@@ -153,8 +154,8 @@ func IsWithinWeakSubjectivityPeriod(
 // Within the weak subjectivity period, if two conflicting blocks are finalized, 1/3 - D (D := safety decay)
 // of validators will get slashed. Therefore, it is safe to assume that any finalized checkpoint within that
 // period is protected by this safety margin.
-func LatestWeakSubjectivityEpoch(ctx context.Context, st state.ReadOnlyBeaconState) (types.Epoch, error) {
-	wsPeriod, err := ComputeWeakSubjectivityPeriod(ctx, st)
+func LatestWeakSubjectivityEpoch(ctx context.Context, st state.ReadOnlyBeaconState, cfg *params.BeaconChainConfig) (types.Epoch, error) {
+	wsPeriod, err := ComputeWeakSubjectivityPeriod(ctx, st, cfg)
 	if err != nil {
 		return 0, err
 	}
@@ -164,7 +165,7 @@ func LatestWeakSubjectivityEpoch(ctx context.Context, st state.ReadOnlyBeaconSta
 }
 
 // ParseWeakSubjectivityInputString parses "blocks_root:epoch_number" string into a checkpoint.
-func ParseWeakSubjectivityInputString(wsCheckpointString string) (*eth.Checkpoint, error) {
+func ParseWeakSubjectivityInputString(wsCheckpointString string) (*v1alpha1.Checkpoint, error) {
 	if wsCheckpointString == "" {
 		return nil, nil
 	}
@@ -197,7 +198,7 @@ func ParseWeakSubjectivityInputString(wsCheckpointString string) (*eth.Checkpoin
 		return nil, err
 	}
 
-	return &eth.Checkpoint{
+	return &v1alpha1.Checkpoint{
 		Epoch: types.Epoch(epoch),
 		Root:  bRoot,
 	}, nil

beacon-chain/core/helpers/weak_subjectivity_test.go

@@ -48,18 +48,21 @@ func TestWeakSubjectivity_ComputeWeakSubjectivityPeriod(t *testing.T) {
 		t.Run(fmt.Sprintf("valCount: %d, avgBalance: %d", tt.valCount, tt.avgBalance), func(t *testing.T) {
 			// Reset committee cache - as we need to recalculate active validator set for each test.
 			helpers.ClearCache()
-			got, err := helpers.ComputeWeakSubjectivityPeriod(context.Background(), genState(t, tt.valCount, tt.avgBalance))
+			got, err := helpers.ComputeWeakSubjectivityPeriod(context.Background(), genState(t, tt.valCount, tt.avgBalance), params.BeaconConfig())
 			require.NoError(t, err)
 			assert.Equal(t, tt.want, got, "valCount: %v, avgBalance: %v", tt.valCount, tt.avgBalance)
 		})
 	}
 }
+
+type mockWsCheckpoint func() (stateRoot [32]byte, blockRoot [32]byte, e types.Epoch)
+
 func TestWeakSubjectivity_IsWithinWeakSubjectivityPeriod(t *testing.T) {
 	tests := []struct {
 		name            string
 		epoch           types.Epoch
 		genWsState      func() state.ReadOnlyBeaconState
-		genWsCheckpoint func() *ethpb.WeakSubjectivityCheckpoint
+		genWsCheckpoint mockWsCheckpoint
 		want            bool
 		wantedErr       string
 	}{
@@ -68,22 +71,8 @@ func TestWeakSubjectivity_IsWithinWeakSubjectivityPeriod(t *testing.T) {
 			genWsState: func() state.ReadOnlyBeaconState {
 				return nil
 			},
-			genWsCheckpoint: func() *ethpb.WeakSubjectivityCheckpoint {
-				return &ethpb.WeakSubjectivityCheckpoint{
-					BlockRoot: make([]byte, 32),
-					StateRoot: make([]byte, 32),
-					Epoch:     42,
-				}
-			},
-			wantedErr: "invalid weak subjectivity state or checkpoint",
-		},
-		{
-			name: "nil weak subjectivity checkpoint",
-			genWsState: func() state.ReadOnlyBeaconState {
-				return genState(t, 128, 32)
-			},
-			genWsCheckpoint: func() *ethpb.WeakSubjectivityCheckpoint {
-				return nil
+			genWsCheckpoint: func() ([32]byte, [32]byte, types.Epoch) {
+				return [32]byte{}, [32]byte{}, 42
 			},
 			wantedErr: "invalid weak subjectivity state or checkpoint",
 		},
@@ -99,11 +88,10 @@ func TestWeakSubjectivity_IsWithinWeakSubjectivityPeriod(t *testing.T) {
 				require.NoError(t, err)
 				return beaconState
 			},
-			genWsCheckpoint: func() *ethpb.WeakSubjectivityCheckpoint {
-				return &ethpb.WeakSubjectivityCheckpoint{
-					StateRoot: bytesutil.PadTo([]byte("stateroot2"), 32),
-					Epoch:     42,
-				}
+			genWsCheckpoint: func() ([32]byte, [32]byte, types.Epoch) {
+				var sr [32]byte
+				copy(sr[:], bytesutil.PadTo([]byte("stateroot2"), 32))
+				return sr, [32]byte{}, 42
 			},
 			wantedErr: fmt.Sprintf("state (%#x) and checkpoint (%#x) roots do not match",
 				bytesutil.PadTo([]byte("stateroot1"), 32), bytesutil.PadTo([]byte("stateroot2"), 32)),
@@ -120,11 +108,10 @@ func TestWeakSubjectivity_IsWithinWeakSubjectivityPeriod(t *testing.T) {
 				require.NoError(t, err)
 				return beaconState
 			},
-			genWsCheckpoint: func() *ethpb.WeakSubjectivityCheckpoint {
-				return &ethpb.WeakSubjectivityCheckpoint{
-					StateRoot: bytesutil.PadTo([]byte("stateroot"), 32),
-					Epoch:     43,
-				}
+			genWsCheckpoint: func() ([32]byte, [32]byte, types.Epoch) {
+				var sr [32]byte
+				copy(sr[:], bytesutil.PadTo([]byte("stateroot"), 32))
+				return sr, [32]byte{}, 43
 			},
 			wantedErr: "state (42) and checkpoint (43) epochs do not match",
 		},
@@ -140,11 +127,10 @@ func TestWeakSubjectivity_IsWithinWeakSubjectivityPeriod(t *testing.T) {
 				require.NoError(t, err)
 				return beaconState
 			},
-			genWsCheckpoint: func() *ethpb.WeakSubjectivityCheckpoint {
-				return &ethpb.WeakSubjectivityCheckpoint{
-					StateRoot: bytesutil.PadTo([]byte("stateroot"), 32),
-					Epoch:     42,
-				}
+			genWsCheckpoint: func() ([32]byte, [32]byte, types.Epoch) {
+				var sr [32]byte
+				copy(sr[:], bytesutil.PadTo([]byte("stateroot"), 32))
+				return sr, [32]byte{}, 42
 			},
 			wantedErr: "cannot compute weak subjectivity period: no active validators found",
 		},
@@ -161,11 +147,10 @@ func TestWeakSubjectivity_IsWithinWeakSubjectivityPeriod(t *testing.T) {
 				require.NoError(t, err)
 				return beaconState
 			},
-			genWsCheckpoint: func() *ethpb.WeakSubjectivityCheckpoint {
-				return &ethpb.WeakSubjectivityCheckpoint{
-					StateRoot: bytesutil.PadTo([]byte("stateroot"), 32),
-					Epoch:     42,
-				}
+			genWsCheckpoint: func() ([32]byte, [32]byte, types.Epoch) {
+				var sr [32]byte
+				copy(sr[:], bytesutil.PadTo([]byte("stateroot"), 32))
+				return sr, [32]byte{}, 42
 			},
 			want: false,
 		},
@@ -182,18 +167,18 @@ func TestWeakSubjectivity_IsWithinWeakSubjectivityPeriod(t *testing.T) {
 				require.NoError(t, err)
 				return beaconState
 			},
-			genWsCheckpoint: func() *ethpb.WeakSubjectivityCheckpoint {
-				return &ethpb.WeakSubjectivityCheckpoint{
-					StateRoot: bytesutil.PadTo([]byte("stateroot"), 32),
-					Epoch:     42,
-				}
+			genWsCheckpoint: func() ([32]byte, [32]byte, types.Epoch) {
+				var sr [32]byte
+				copy(sr[:], bytesutil.PadTo([]byte("stateroot"), 32))
+				return sr, [32]byte{}, 42
 			},
 			want: true,
 		},
 	}
 	for _, tt := range tests {
 		t.Run(tt.name, func(t *testing.T) {
-			got, err := helpers.IsWithinWeakSubjectivityPeriod(context.Background(), tt.epoch, tt.genWsState(), tt.genWsCheckpoint())
+			sr, _, e := tt.genWsCheckpoint()
+			got, err := helpers.IsWithinWeakSubjectivityPeriod(context.Background(), tt.epoch, tt.genWsState(), sr, e, params.BeaconConfig())
 			if tt.wantedErr != "" {
 				assert.Equal(t, false, got)
 				assert.ErrorContains(t, tt.wantedErr, err)

beacon-chain/core/time/BUILD.bazel

@@ -17,13 +17,15 @@ go_library(
 go_test(
     name = "go_default_test",
     srcs = ["slot_epoch_test.go"],
-    embed = [":go_default_library"],
     deps = [
+        ":go_default_library",
+        "//beacon-chain/state:go_default_library",
         "//beacon-chain/state/v1:go_default_library",
         "//config/params:go_default_library",
         "//proto/prysm/v1alpha1:go_default_library",
         "//testing/assert:go_default_library",
         "//testing/require:go_default_library",
+        "//testing/util:go_default_library",
         "//time/slots:go_default_library",
         "@com_github_prysmaticlabs_eth2_types//:go_default_library",
     ],

beacon-chain/core/time/slot_epoch.go

@@ -46,9 +46,9 @@ func NextEpoch(state state.ReadOnlyBeaconState) types.Epoch {
 	return slots.ToEpoch(state.Slot()) + 1
 }
 
-// AltairCompatible returns if the input state `s` is altair compatible and input epoch `e` is higher equal than fork epoch.
-func AltairCompatible(s state.BeaconState, e types.Epoch) bool {
-	return s.Version() == version.Altair && e >= params.BeaconConfig().AltairForkEpoch
+// HigherEqualThanAltairVersionAndEpoch returns if the input state `s` has a higher version number than Altair state and input epoch `e` is higher equal than fork epoch.
+func HigherEqualThanAltairVersionAndEpoch(s state.BeaconState, e types.Epoch) bool {
+	return s.Version() >= version.Altair && e >= params.BeaconConfig().AltairForkEpoch
 }
 
 // CanUpgradeToAltair returns true if the input `slot` can upgrade to Altair.

beacon-chain/core/time/slot_epoch_test.go

@@ -1,14 +1,17 @@
-package time
+package time_test
 
 import (
 	"testing"
 
 	types "github.com/prysmaticlabs/eth2-types"
+	"github.com/prysmaticlabs/prysm/beacon-chain/core/time"
+	"github.com/prysmaticlabs/prysm/beacon-chain/state"
 	v1 "github.com/prysmaticlabs/prysm/beacon-chain/state/v1"
 	"github.com/prysmaticlabs/prysm/config/params"
 	eth "github.com/prysmaticlabs/prysm/proto/prysm/v1alpha1"
 	"github.com/prysmaticlabs/prysm/testing/assert"
 	"github.com/prysmaticlabs/prysm/testing/require"
+	"github.com/prysmaticlabs/prysm/testing/util"
 	"github.com/prysmaticlabs/prysm/time/slots"
 )
 
@@ -42,7 +45,7 @@ func TestCurrentEpoch_OK(t *testing.T) {
 	for _, tt := range tests {
 		state, err := v1.InitializeFromProto(&eth.BeaconState{Slot: tt.slot})
 		require.NoError(t, err)
-		assert.Equal(t, tt.epoch, CurrentEpoch(state), "ActiveCurrentEpoch(%d)", state.Slot())
+		assert.Equal(t, tt.epoch, time.CurrentEpoch(state), "ActiveCurrentEpoch(%d)", state.Slot())
 	}
 }
 
@@ -58,7 +61,7 @@ func TestPrevEpoch_OK(t *testing.T) {
 	for _, tt := range tests {
 		state, err := v1.InitializeFromProto(&eth.BeaconState{Slot: tt.slot})
 		require.NoError(t, err)
-		assert.Equal(t, tt.epoch, PrevEpoch(state), "ActivePrevEpoch(%d)", state.Slot())
+		assert.Equal(t, tt.epoch, time.PrevEpoch(state), "ActivePrevEpoch(%d)", state.Slot())
 	}
 }
 
@@ -76,7 +79,7 @@ func TestNextEpoch_OK(t *testing.T) {
 	for _, tt := range tests {
 		state, err := v1.InitializeFromProto(&eth.BeaconState{Slot: tt.slot})
 		require.NoError(t, err)
-		assert.Equal(t, tt.epoch, NextEpoch(state), "NextEpoch(%d)", state.Slot())
+		assert.Equal(t, tt.epoch, time.NextEpoch(state), "NextEpoch(%d)", state.Slot())
 	}
 }
 
@@ -108,7 +111,7 @@ func TestCanUpgradeToAltair(t *testing.T) {
 	}
 	for _, tt := range tests {
 		t.Run(tt.name, func(t *testing.T) {
-			if got := CanUpgradeToAltair(tt.slot); got != tt.want {
+			if got := time.CanUpgradeToAltair(tt.slot); got != tt.want {
 				t.Errorf("canUpgradeToAltair() = %v, want %v", got, tt.want)
 			}
 		})
@@ -143,7 +146,7 @@ func TestCanUpgradeBellatrix(t *testing.T) {
 	}
 	for _, tt := range tests {
 		t.Run(tt.name, func(t *testing.T) {
-			if got := CanUpgradeToBellatrix(tt.slot); got != tt.want {
+			if got := time.CanUpgradeToBellatrix(tt.slot); got != tt.want {
 				t.Errorf("CanUpgradeToBellatrix() = %v, want %v", got, tt.want)
 			}
 		})
@@ -178,6 +181,85 @@ func TestCanProcessEpoch_TrueOnEpochsLastSlot(t *testing.T) {
 		b := &eth.BeaconState{Slot: tt.slot}
 		s, err := v1.InitializeFromProto(b)
 		require.NoError(t, err)
-		assert.Equal(t, tt.canProcessEpoch, CanProcessEpoch(s), "CanProcessEpoch(%d)", tt.slot)
+		assert.Equal(t, tt.canProcessEpoch, time.CanProcessEpoch(s), "CanProcessEpoch(%d)", tt.slot)
+	}
+}
+
+func TestAltairCompatible(t *testing.T) {
+	params.SetupTestConfigCleanup(t)
+	cfg := params.BeaconConfig()
+	cfg.AltairForkEpoch = 1
+	cfg.BellatrixForkEpoch = 2
+	params.OverrideBeaconConfig(cfg)
+
+	type args struct {
+		s state.BeaconState
+		e types.Epoch
+	}
+	tests := []struct {
+		name string
+		args args
+		want bool
+	}{
+		{
+			name: "phase0 state",
+			args: args{
+				s: func() state.BeaconState {
+					st, _ := util.DeterministicGenesisState(t, 1)
+					return st
+				}(),
+			},
+			want: false,
+		},
+		{
+			name: "altair state, altair epoch",
+			args: args{
+				s: func() state.BeaconState {
+					st, _ := util.DeterministicGenesisStateAltair(t, 1)
+					return st
+				}(),
+				e: params.BeaconConfig().AltairForkEpoch,
+			},
+			want: true,
+		},
+		{
+			name: "bellatrix state, bellatrix epoch",
+			args: args{
+				s: func() state.BeaconState {
+					st, _ := util.DeterministicGenesisStateBellatrix(t, 1)
+					return st
+				}(),
+				e: params.BeaconConfig().BellatrixForkEpoch,
+			},
+			want: true,
+		},
+		{
+			name: "bellatrix state, altair epoch",
+			args: args{
+				s: func() state.BeaconState {
+					st, _ := util.DeterministicGenesisStateBellatrix(t, 1)
+					return st
+				}(),
+				e: params.BeaconConfig().AltairForkEpoch,
+			},
+			want: true,
+		},
+		{
+			name: "bellatrix state, phase0 epoch",
+			args: args{
+				s: func() state.BeaconState {
+					st, _ := util.DeterministicGenesisStateBellatrix(t, 1)
+					return st
+				}(),
+			},
+			want: false,
+		},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			if got := time.HigherEqualThanAltairVersionAndEpoch(tt.args.s, tt.args.e); got != tt.want {
+				t.Errorf("HigherEqualThanAltairVersionAndEpoch() = %v, want %v", got, tt.want)
+			}
+		})
 	}
 }

beacon-chain/core/transition/altair_transition_no_verify_sig_test.go

@@ -90,7 +90,7 @@ func TestExecuteAltairStateTransitionNoVerify_FullProcess(t *testing.T) {
 		SyncCommitteeSignature: aggregatedSig,
 	}
 	block.Block.Body.SyncAggregate = syncAggregate
-	wsb, err := wrapper.WrappedAltairSignedBeaconBlock(block)
+	wsb, err := wrapper.WrappedSignedBeaconBlock(block)
 	require.NoError(t, err)
 	stateRoot, err := transition.CalculateStateRoot(context.Background(), beaconState, wsb)
 	require.NoError(t, err)
@@ -101,7 +101,7 @@ func TestExecuteAltairStateTransitionNoVerify_FullProcess(t *testing.T) {
 	require.NoError(t, err)
 	block.Signature = sig.Marshal()
 
-	wsb, err = wrapper.WrappedAltairSignedBeaconBlock(block)
+	wsb, err = wrapper.WrappedSignedBeaconBlock(block)
 	require.NoError(t, err)
 	set, _, err := transition.ExecuteStateTransitionNoVerifyAnySig(context.Background(), beaconState, wsb)
 	require.NoError(t, err)
@@ -178,7 +178,7 @@ func TestExecuteAltairStateTransitionNoVerifySignature_CouldNotVerifyStateRoot(t
 	}
 	block.Block.Body.SyncAggregate = syncAggregate
 
-	wsb, err := wrapper.WrappedAltairSignedBeaconBlock(block)
+	wsb, err := wrapper.WrappedSignedBeaconBlock(block)
 	require.NoError(t, err)
 	stateRoot, err := transition.CalculateStateRoot(context.Background(), beaconState, wsb)
 	require.NoError(t, err)
@@ -190,7 +190,7 @@ func TestExecuteAltairStateTransitionNoVerifySignature_CouldNotVerifyStateRoot(t
 	block.Signature = sig.Marshal()
 
 	block.Block.StateRoot = bytesutil.PadTo([]byte{'a'}, 32)
-	wsb, err = wrapper.WrappedAltairSignedBeaconBlock(block)
+	wsb, err = wrapper.WrappedSignedBeaconBlock(block)
 	require.NoError(t, err)
 	_, _, err = transition.ExecuteStateTransitionNoVerifyAnySig(context.Background(), beaconState, wsb)
 	require.ErrorContains(t, "could not validate state root", err)
@@ -198,7 +198,7 @@ func TestExecuteAltairStateTransitionNoVerifySignature_CouldNotVerifyStateRoot(t
 
 func TestExecuteStateTransitionNoVerifyAnySig_PassesProcessingConditions(t *testing.T) {
 	beaconState, block := createFullAltairBlockWithOperations(t)
-	wsb, err := wrapper.WrappedAltairSignedBeaconBlock(block)
+	wsb, err := wrapper.WrappedSignedBeaconBlock(block)
 	require.NoError(t, err)
 	set, _, err := transition.ExecuteStateTransitionNoVerifyAnySig(context.Background(), beaconState, wsb)
 	require.NoError(t, err)

beacon-chain/core/transition/bellatrix_transition_no_verify_sig_test.go

@@ -92,7 +92,7 @@ func TestExecuteBellatrixStateTransitionNoVerify_FullProcess(t *testing.T) {
 		SyncCommitteeSignature: aggregatedSig,
 	}
 	block.Block.Body.SyncAggregate = syncAggregate
-	wsb, err := wrapper.WrappedBellatrixSignedBeaconBlock(block)
+	wsb, err := wrapper.WrappedSignedBeaconBlock(block)
 	require.NoError(t, err)
 	stateRoot, err := transition.CalculateStateRoot(context.Background(), beaconState, wsb)
 	require.NoError(t, err)
@@ -103,7 +103,7 @@ func TestExecuteBellatrixStateTransitionNoVerify_FullProcess(t *testing.T) {
 	require.NoError(t, err)
 	block.Signature = sig.Marshal()
 
-	wsb, err = wrapper.WrappedBellatrixSignedBeaconBlock(block)
+	wsb, err = wrapper.WrappedSignedBeaconBlock(block)
 	require.NoError(t, err)
 	set, _, err := transition.ExecuteStateTransitionNoVerifyAnySig(context.Background(), beaconState, wsb)
 	require.NoError(t, err)
@@ -180,7 +180,7 @@ func TestExecuteBellatrixStateTransitionNoVerifySignature_CouldNotVerifyStateRoo
 	}
 	block.Block.Body.SyncAggregate = syncAggregate
 
-	wsb, err := wrapper.WrappedBellatrixSignedBeaconBlock(block)
+	wsb, err := wrapper.WrappedSignedBeaconBlock(block)
 	require.NoError(t, err)
 	stateRoot, err := transition.CalculateStateRoot(context.Background(), beaconState, wsb)
 	require.NoError(t, err)
@@ -192,7 +192,7 @@ func TestExecuteBellatrixStateTransitionNoVerifySignature_CouldNotVerifyStateRoo
 	block.Signature = sig.Marshal()
 
 	block.Block.StateRoot = bytesutil.PadTo([]byte{'a'}, 32)
-	wsb, err = wrapper.WrappedBellatrixSignedBeaconBlock(block)
+	wsb, err = wrapper.WrappedSignedBeaconBlock(block)
 	require.NoError(t, err)
 	_, _, err = transition.ExecuteStateTransitionNoVerifyAnySig(context.Background(), beaconState, wsb)
 	require.ErrorContains(t, "could not validate state root", err)
@@ -245,7 +245,7 @@ func createFullBellatrixBlockWithOperations(t *testing.T) (state.BeaconState,
 					ReceiptsRoot:  make([]byte, fieldparams.RootLength),
 					LogsBloom:     make([]byte, fieldparams.LogsBloomLength),
 					PrevRandao:    make([]byte, fieldparams.RootLength),
-					BaseFeePerGas: make([]byte, fieldparams.RootLength),
+					BaseFeePerGas: bytesutil.PadTo([]byte{1, 2, 3, 4}, fieldparams.RootLength),
 					BlockHash:     make([]byte, fieldparams.RootLength),
 					Transactions:  make([][]byte, 0),
 					ExtraData:     make([]byte, 0),

beacon-chain/core/transition/benchmarks_test.go

@@ -29,7 +29,9 @@ func BenchmarkExecuteStateTransition_FullBlock(b *testing.B) {
 
 	b.ResetTimer()
 	for i := 0; i < b.N; i++ {
-		_, err := coreState.ExecuteStateTransition(context.Background(), cleanStates[i], wrapper.WrappedPhase0SignedBeaconBlock(block))
+		wsb, err := wrapper.WrappedSignedBeaconBlock(block)
+		require.NoError(b, err)
+		_, err = coreState.ExecuteStateTransition(context.Background(), cleanStates[i], wsb)
 		require.NoError(b, err)
 	}
 }
@@ -50,12 +52,16 @@ func BenchmarkExecuteStateTransition_WithCache(b *testing.B) {
 	require.NoError(b, helpers.UpdateCommitteeCache(beaconState, time.CurrentEpoch(beaconState)))
 	require.NoError(b, beaconState.SetSlot(currentSlot))
 	// Run the state transition once to populate the cache.
-	_, err = coreState.ExecuteStateTransition(context.Background(), beaconState, wrapper.WrappedPhase0SignedBeaconBlock(block))
+	wsb, err := wrapper.WrappedSignedBeaconBlock(block)
+	require.NoError(b, err)
+	_, err = coreState.ExecuteStateTransition(context.Background(), beaconState, wsb)
 	require.NoError(b, err, "Failed to process block, benchmarks will fail")
 
 	b.ResetTimer()
 	for i := 0; i < b.N; i++ {
-		_, err := coreState.ExecuteStateTransition(context.Background(), cleanStates[i], wrapper.WrappedPhase0SignedBeaconBlock(block))
+		wsb, err := wrapper.WrappedSignedBeaconBlock(block)
+		require.NoError(b, err)
+		_, err = coreState.ExecuteStateTransition(context.Background(), cleanStates[i], wsb)
 		require.NoError(b, err, "Failed to process block, benchmarks will fail")
 	}
 }

beacon-chain/core/transition/skip_slot_cache_test.go

@@ -32,10 +32,14 @@ func TestSkipSlotCache_OK(t *testing.T) {
 	// with the state
 	blk, err := util.GenerateFullBlock(bState, privs, blkCfg, originalState.Slot()+10)
 	require.NoError(t, err)
-	executedState, err := transition.ExecuteStateTransition(context.Background(), originalState, wrapper.WrappedPhase0SignedBeaconBlock(blk))
+	wsb, err := wrapper.WrappedSignedBeaconBlock(blk)
+	require.NoError(t, err)
+	executedState, err := transition.ExecuteStateTransition(context.Background(), originalState, wsb)
 	require.NoError(t, err, "Could not run state transition")
 	require.Equal(t, true, executedState.Version() == version.Phase0)
-	bState, err = transition.ExecuteStateTransition(context.Background(), bState, wrapper.WrappedPhase0SignedBeaconBlock(blk))
+	wsb, err = wrapper.WrappedSignedBeaconBlock(blk)
+	require.NoError(t, err)
+	bState, err = transition.ExecuteStateTransition(context.Background(), bState, wsb)
 	require.NoError(t, err, "Could not process state transition")
 
 	assert.DeepEqual(t, originalState.CloneInnerState(), bState.CloneInnerState(), "Skipped slots cache leads to different states")
@@ -57,7 +61,9 @@ func TestSkipSlotCache_ConcurrentMixup(t *testing.T) {
 	// with the state
 	blk, err := util.GenerateFullBlock(bState, privs, blkCfg, originalState.Slot()+10)
 	require.NoError(t, err)
-	executedState, err := transition.ExecuteStateTransition(context.Background(), originalState, wrapper.WrappedPhase0SignedBeaconBlock(blk))
+	wsb, err := wrapper.WrappedSignedBeaconBlock(blk)
+	require.NoError(t, err)
+	executedState, err := transition.ExecuteStateTransition(context.Background(), originalState, wsb)
 	require.NoError(t, err, "Could not run state transition")
 	require.Equal(t, true, executedState.Version() == version.Phase0)
 
@@ -70,7 +76,9 @@ func TestSkipSlotCache_ConcurrentMixup(t *testing.T) {
 		signature, err := util.BlockSignature(originalState, blk.Block, privs)
 		require.NoError(t, err)
 		blk.Signature = signature.Marshal()
-		s1, err = transition.ExecuteStateTransition(context.Background(), originalState.Copy(), wrapper.WrappedPhase0SignedBeaconBlock(blk))
+		wsb, err := wrapper.WrappedSignedBeaconBlock(blk)
+		require.NoError(t, err)
+		s1, err = transition.ExecuteStateTransition(context.Background(), originalState.Copy(), wsb)
 		require.NoError(t, err, "Could not run state transition")
 	}
 
@@ -81,7 +89,9 @@ func TestSkipSlotCache_ConcurrentMixup(t *testing.T) {
 		signature, err := util.BlockSignature(originalState, blk.Block, privs)
 		require.NoError(t, err)
 		blk.Signature = signature.Marshal()
-		s0, err = transition.ExecuteStateTransition(context.Background(), originalState.Copy(), wrapper.WrappedPhase0SignedBeaconBlock(blk))
+		wsb, err := wrapper.WrappedSignedBeaconBlock(blk)
+		require.NoError(t, err)
+		s0, err = transition.ExecuteStateTransition(context.Background(), originalState.Copy(), wsb)
 		require.NoError(t, err, "Could not run state transition")
 	}
 

beacon-chain/core/transition/transition.go

@@ -92,7 +92,7 @@ func ExecuteStateTransition(
 func ProcessSlot(ctx context.Context, state state.BeaconState) (state.BeaconState, error) {
 	ctx, span := trace.StartSpan(ctx, "core.state.ProcessSlot")
 	defer span.End()
-	span.AddAttributes(trace.Int64Attribute("slot", int64(state.Slot())))
+	span.AddAttributes(trace.Int64Attribute("slot", int64(state.Slot()))) // lint:ignore uintcast -- This is OK for tracing.
 
 	prevStateRoot, err := state.HashTreeRoot(ctx)
 	if err != nil {
@@ -190,7 +190,7 @@ func ProcessSlots(ctx context.Context, state state.BeaconState, slot types.Slot)
 	if state == nil || state.IsNil() {
 		return nil, errors.New("nil state")
 	}
-	span.AddAttributes(trace.Int64Attribute("slots", int64(slot)-int64(state.Slot())))
+	span.AddAttributes(trace.Int64Attribute("slots", int64(slot)-int64(state.Slot()))) // lint:ignore uintcast -- This is OK for tracing.
 
 	// The block must have a higher slot than parent state.
 	if state.Slot() >= slot {
@@ -354,7 +354,7 @@ func VerifyOperationLengths(_ context.Context, state state.BeaconState, b block.
 func ProcessEpochPrecompute(ctx context.Context, state state.BeaconState) (state.BeaconState, error) {
 	ctx, span := trace.StartSpan(ctx, "core.state.ProcessEpochPrecompute")
 	defer span.End()
-	span.AddAttributes(trace.Int64Attribute("epoch", int64(time.CurrentEpoch(state))))
+	span.AddAttributes(trace.Int64Attribute("epoch", int64(time.CurrentEpoch(state)))) // lint:ignore uintcast -- This is OK for tracing.
 
 	if state == nil || state.IsNil() {
 		return nil, errors.New("nil state")

beacon-chain/core/transition/transition_fuzz_test.go

@@ -25,7 +25,9 @@ func TestFuzzExecuteStateTransition_1000(t *testing.T) {
 	for i := 0; i < 1000; i++ {
 		fuzzer.Fuzz(state)
 		fuzzer.Fuzz(sb)
-		s, err := ExecuteStateTransition(ctx, state, wrapper.WrappedPhase0SignedBeaconBlock(sb))
+		wsb, err := wrapper.WrappedSignedBeaconBlock(sb)
+		require.NoError(t, err)
+		s, err := ExecuteStateTransition(ctx, state, wsb)
 		if err != nil && s != nil {
 			t.Fatalf("state should be nil on err. found: %v on error: %v for state: %v and signed block: %v", s, err, state, sb)
 		}
@@ -44,7 +46,9 @@ func TestFuzzCalculateStateRoot_1000(t *testing.T) {
 	for i := 0; i < 1000; i++ {
 		fuzzer.Fuzz(state)
 		fuzzer.Fuzz(sb)
-		stateRoot, err := CalculateStateRoot(ctx, state, wrapper.WrappedPhase0SignedBeaconBlock(sb))
+		wsb, err := wrapper.WrappedSignedBeaconBlock(sb)
+		require.NoError(t, err)
+		stateRoot, err := CalculateStateRoot(ctx, state, wsb)
 		if err != nil && stateRoot != [32]byte{} {
 			t.Fatalf("state root should be empty on err. found: %v on error: %v for signed block: %v", stateRoot, err, sb)
 		}
@@ -99,7 +103,9 @@ func TestFuzzprocessOperationsNoVerify_1000(t *testing.T) {
 	for i := 0; i < 1000; i++ {
 		fuzzer.Fuzz(state)
 		fuzzer.Fuzz(bb)
-		s, err := ProcessOperationsNoVerifyAttsSigs(ctx, state, wrapper.WrappedPhase0SignedBeaconBlock(bb))
+		wsb, err := wrapper.WrappedSignedBeaconBlock(bb)
+		require.NoError(t, err)
+		s, err := ProcessOperationsNoVerifyAttsSigs(ctx, state, wsb)
 		if err != nil && s != nil {
 			t.Fatalf("state should be nil on err. found: %v on error: %v for block body: %v", s, err, bb)
 		}
@@ -117,7 +123,9 @@ func TestFuzzverifyOperationLengths_10000(t *testing.T) {
 	for i := 0; i < 10000; i++ {
 		fuzzer.Fuzz(state)
 		fuzzer.Fuzz(bb)
-		_, err := VerifyOperationLengths(context.Background(), state, wrapper.WrappedPhase0SignedBeaconBlock(bb))
+		wsb, err := wrapper.WrappedSignedBeaconBlock(bb)
+		require.NoError(t, err)
+		_, err = VerifyOperationLengths(context.Background(), state, wsb)
 		_ = err
 	}
 }
@@ -164,7 +172,9 @@ func TestFuzzProcessBlockForStateRoot_1000(t *testing.T) {
 	for i := 0; i < 1000; i++ {
 		fuzzer.Fuzz(state)
 		fuzzer.Fuzz(sb)
-		s, err := ProcessBlockForStateRoot(ctx, state, wrapper.WrappedPhase0SignedBeaconBlock(sb))
+		wsb, err := wrapper.WrappedSignedBeaconBlock(sb)
+		require.NoError(t, err)
+		s, err := ProcessBlockForStateRoot(ctx, state, wsb)
 		if err != nil && s != nil {
 			t.Fatalf("state should be nil on err. found: %v on error: %v for signed block: %v", s, err, sb)
 		}

beacon-chain/core/transition/transition_no_verify_sig.go

@@ -137,16 +137,6 @@ func CalculateStateRoot(
 	if err != nil {
 		return [32]byte{}, errors.Wrap(err, "could not process block")
 	}
-	if signed.Version() == version.Altair || signed.Version() == version.Bellatrix {
-		sa, err := signed.Block().Body().SyncAggregate()
-		if err != nil {
-			return [32]byte{}, err
-		}
-		state, err = altair.ProcessSyncAggregate(ctx, state, sa)
-		if err != nil {
-			return [32]byte{}, err
-		}
-	}
 
 	return state.HashTreeRoot(ctx)
 }
@@ -183,16 +173,6 @@ func ProcessBlockNoVerifyAnySig(
 	if err != nil {
 		return nil, nil, err
 	}
-	if signed.Version() == version.Altair || signed.Version() == version.Bellatrix {
-		sa, err := signed.Block().Body().SyncAggregate()
-		if err != nil {
-			return nil, nil, err
-		}
-		state, err = altair.ProcessSyncAggregate(ctx, state, sa)
-		if err != nil {
-			return nil, nil, err
-		}
-	}
 
 	bSet, err := b.BlockSignatureBatch(state, blk.ProposerIndex(), signed.Signature(), blk.HashTreeRoot)
 	if err != nil {
@@ -305,20 +285,18 @@ func ProcessBlockForStateRoot(
 		return nil, errors.Wrap(err, "could not process block header")
 	}
 
-	if state.Version() == version.Bellatrix {
-		enabled, err := b.ExecutionEnabled(state, blk.Body())
+	enabled, err := b.IsExecutionEnabled(state, blk.Body())
+	if err != nil {
+		return nil, errors.Wrap(err, "could not check if execution is enabled")
+	}
+	if enabled {
+		payload, err := blk.Body().ExecutionPayload()
 		if err != nil {
-			return nil, errors.Wrap(err, "could not check if execution is enabled")
+			return nil, err
 		}
-		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")
-			}
+		state, err = b.ProcessPayload(state, payload)
+		if err != nil {
+			return nil, errors.Wrap(err, "could not process execution payload")
 		}
 	}
 
@@ -340,6 +318,19 @@ func ProcessBlockForStateRoot(
 		return nil, errors.Wrap(err, "could not process block operation")
 	}
 
+	if signed.Block().Version() == version.Phase0 {
+		return state, nil
+	}
+
+	sa, err := signed.Block().Body().SyncAggregate()
+	if err != nil {
+		return nil, errors.Wrap(err, "could not get sync aggregate from block")
+	}
+	state, err = altair.ProcessSyncAggregate(ctx, state, sa)
+	if err != nil {
+		return nil, errors.Wrap(err, "process_sync_aggregate failed")
+	}
+
 	return state, nil
 }
 

beacon-chain/core/transition/transition_no_verify_sig_test.go

@@ -52,7 +52,9 @@ func TestExecuteStateTransitionNoVerify_FullProcess(t *testing.T) {
 	block.Block.Body.RandaoReveal = randaoReveal
 	block.Block.Body.Eth1Data = eth1Data
 
-	stateRoot, err := transition.CalculateStateRoot(context.Background(), beaconState, wrapper.WrappedPhase0SignedBeaconBlock(block))
+	wsb, err := wrapper.WrappedSignedBeaconBlock(block)
+	require.NoError(t, err)
+	stateRoot, err := transition.CalculateStateRoot(context.Background(), beaconState, wsb)
 	require.NoError(t, err)
 
 	block.Block.StateRoot = stateRoot[:]
@@ -61,7 +63,9 @@ func TestExecuteStateTransitionNoVerify_FullProcess(t *testing.T) {
 	require.NoError(t, err)
 	block.Signature = sig.Marshal()
 
-	set, _, err := transition.ExecuteStateTransitionNoVerifyAnySig(context.Background(), beaconState, wrapper.WrappedPhase0SignedBeaconBlock(block))
+	wsb, err = wrapper.WrappedSignedBeaconBlock(block)
+	require.NoError(t, err)
+	set, _, err := transition.ExecuteStateTransitionNoVerifyAnySig(context.Background(), beaconState, wsb)
 	assert.NoError(t, err)
 	verified, err := set.Verify()
 	assert.NoError(t, err)
@@ -104,7 +108,9 @@ func TestExecuteStateTransitionNoVerifySignature_CouldNotVerifyStateRoot(t *test
 	block.Block.Body.RandaoReveal = randaoReveal
 	block.Block.Body.Eth1Data = eth1Data
 
-	stateRoot, err := transition.CalculateStateRoot(context.Background(), beaconState, wrapper.WrappedPhase0SignedBeaconBlock(block))
+	wsb, err := wrapper.WrappedSignedBeaconBlock(block)
+	require.NoError(t, err)
+	stateRoot, err := transition.CalculateStateRoot(context.Background(), beaconState, wsb)
 	require.NoError(t, err)
 
 	block.Block.StateRoot = stateRoot[:]
@@ -114,13 +120,17 @@ func TestExecuteStateTransitionNoVerifySignature_CouldNotVerifyStateRoot(t *test
 	block.Signature = sig.Marshal()
 
 	block.Block.StateRoot = bytesutil.PadTo([]byte{'a'}, 32)
-	_, _, err = transition.ExecuteStateTransitionNoVerifyAnySig(context.Background(), beaconState, wrapper.WrappedPhase0SignedBeaconBlock(block))
+	wsb, err = wrapper.WrappedSignedBeaconBlock(block)
+	require.NoError(t, err)
+	_, _, err = transition.ExecuteStateTransitionNoVerifyAnySig(context.Background(), beaconState, wsb)
 	require.ErrorContains(t, "could not validate state root", err)
 }
 
 func TestProcessBlockNoVerify_PassesProcessingConditions(t *testing.T) {
 	beaconState, block, _, _, _ := createFullBlockWithOperations(t)
-	set, _, err := transition.ProcessBlockNoVerifyAnySig(context.Background(), beaconState, wrapper.WrappedPhase0SignedBeaconBlock(block))
+	wsb, err := wrapper.WrappedSignedBeaconBlock(block)
+	require.NoError(t, err)
+	set, _, err := transition.ProcessBlockNoVerifyAnySig(context.Background(), beaconState, wsb)
 	require.NoError(t, err)
 	// Test Signature set verifies.
 	verified, err := set.Verify()
@@ -130,7 +140,7 @@ func TestProcessBlockNoVerify_PassesProcessingConditions(t *testing.T) {
 
 func TestProcessBlockNoVerifyAnySigAltair_OK(t *testing.T) {
 	beaconState, block := createFullAltairBlockWithOperations(t)
-	wsb, err := wrapper.WrappedAltairSignedBeaconBlock(block)
+	wsb, err := wrapper.WrappedSignedBeaconBlock(block)
 	require.NoError(t, err)
 	beaconState, err = transition.ProcessSlots(context.Background(), beaconState, wsb.Block().Slot())
 	require.NoError(t, err)
@@ -143,7 +153,7 @@ func TestProcessBlockNoVerifyAnySigAltair_OK(t *testing.T) {
 
 func TestProcessOperationsNoVerifyAttsSigs_OK(t *testing.T) {
 	beaconState, block := createFullAltairBlockWithOperations(t)
-	wsb, err := wrapper.WrappedAltairSignedBeaconBlock(block)
+	wsb, err := wrapper.WrappedSignedBeaconBlock(block)
 	require.NoError(t, err)
 	beaconState, err = transition.ProcessSlots(context.Background(), beaconState, wsb.Block().Slot())
 	require.NoError(t, err)
@@ -153,7 +163,7 @@ func TestProcessOperationsNoVerifyAttsSigs_OK(t *testing.T) {
 
 func TestProcessOperationsNoVerifyAttsSigsBellatrix_OK(t *testing.T) {
 	beaconState, block := createFullBellatrixBlockWithOperations(t)
-	wsb, err := wrapper.WrappedBellatrixSignedBeaconBlock(block)
+	wsb, err := wrapper.WrappedSignedBeaconBlock(block)
 	require.NoError(t, err)
 	beaconState, err = transition.ProcessSlots(context.Background(), beaconState, wsb.Block().Slot())
 	require.NoError(t, err)
@@ -163,7 +173,7 @@ func TestProcessOperationsNoVerifyAttsSigsBellatrix_OK(t *testing.T) {
 
 func TestCalculateStateRootAltair_OK(t *testing.T) {
 	beaconState, block := createFullAltairBlockWithOperations(t)
-	wsb, err := wrapper.WrappedAltairSignedBeaconBlock(block)
+	wsb, err := wrapper.WrappedSignedBeaconBlock(block)
 	require.NoError(t, err)
 	r, err := transition.CalculateStateRoot(context.Background(), beaconState, wsb)
 	require.NoError(t, err)
@@ -173,7 +183,7 @@ func TestCalculateStateRootAltair_OK(t *testing.T) {
 func TestProcessBlockDifferentVersion(t *testing.T) {
 	beaconState, _ := util.DeterministicGenesisState(t, 64) // Phase 0 state
 	_, block := createFullAltairBlockWithOperations(t)
-	wsb, err := wrapper.WrappedAltairSignedBeaconBlock(block) // Altair block
+	wsb, err := wrapper.WrappedSignedBeaconBlock(block) // Altair block
 	require.NoError(t, err)
 	_, _, err = transition.ProcessBlockNoVerifyAnySig(context.Background(), beaconState, wsb)
 	require.ErrorContains(t, "state and block are different version. 0 != 1", err)

beacon-chain/core/transition/transition_test.go

@@ -44,7 +44,9 @@ func TestExecuteStateTransition_IncorrectSlot(t *testing.T) {
 		},
 	}
 	want := "expected state.slot"
-	_, err = transition.ExecuteStateTransition(context.Background(), beaconState, wrapper.WrappedPhase0SignedBeaconBlock(block))
+	wsb, err := wrapper.WrappedSignedBeaconBlock(block)
+	require.NoError(t, err)
+	_, err = transition.ExecuteStateTransition(context.Background(), beaconState, wsb)
 	assert.ErrorContains(t, want, err)
 }
 
@@ -87,7 +89,9 @@ func TestExecuteStateTransition_FullProcess(t *testing.T) {
 	block.Block.Body.RandaoReveal = randaoReveal
 	block.Block.Body.Eth1Data = eth1Data
 
-	stateRoot, err := transition.CalculateStateRoot(context.Background(), beaconState, wrapper.WrappedPhase0SignedBeaconBlock(block))
+	wsb, err := wrapper.WrappedSignedBeaconBlock(block)
+	require.NoError(t, err)
+	stateRoot, err := transition.CalculateStateRoot(context.Background(), beaconState, wsb)
 	require.NoError(t, err)
 
 	block.Block.StateRoot = stateRoot[:]
@@ -96,7 +100,9 @@ func TestExecuteStateTransition_FullProcess(t *testing.T) {
 	require.NoError(t, err)
 	block.Signature = sig.Marshal()
 
-	beaconState, err = transition.ExecuteStateTransition(context.Background(), beaconState, wrapper.WrappedPhase0SignedBeaconBlock(block))
+	wsb, err = wrapper.WrappedSignedBeaconBlock(block)
+	require.NoError(t, err)
+	beaconState, err = transition.ExecuteStateTransition(context.Background(), beaconState, wsb)
 	require.NoError(t, err)
 
 	assert.Equal(t, params.BeaconConfig().SlotsPerEpoch, beaconState.Slot(), "Unexpected Slot number")
@@ -183,7 +189,9 @@ func TestProcessBlock_IncorrectProcessExits(t *testing.T) {
 	cp.Root = []byte("hello-world")
 	require.NoError(t, beaconState.SetCurrentJustifiedCheckpoint(cp))
 	require.NoError(t, beaconState.AppendCurrentEpochAttestations(&ethpb.PendingAttestation{}))
-	_, err = transition.VerifyOperationLengths(context.Background(), beaconState, wrapper.WrappedPhase0SignedBeaconBlock(block))
+	wsb, err := wrapper.WrappedSignedBeaconBlock(block)
+	require.NoError(t, err)
+	_, err = transition.VerifyOperationLengths(context.Background(), beaconState, wsb)
 	wanted := "number of voluntary exits (17) in block body exceeds allowed threshold of 16"
 	assert.ErrorContains(t, wanted, err)
 }
@@ -396,7 +404,9 @@ func TestProcessBlock_OverMaxProposerSlashings(t *testing.T) {
 		len(b.Block.Body.ProposerSlashings), params.BeaconConfig().MaxProposerSlashings)
 	s, err := v1.InitializeFromProtoUnsafe(&ethpb.BeaconState{})
 	require.NoError(t, err)
-	_, err = transition.VerifyOperationLengths(context.Background(), s, wrapper.WrappedPhase0SignedBeaconBlock(b))
+	wsb, err := wrapper.WrappedSignedBeaconBlock(b)
+	require.NoError(t, err)
+	_, err = transition.VerifyOperationLengths(context.Background(), s, wsb)
 	assert.ErrorContains(t, want, err)
 }
 
@@ -413,7 +423,9 @@ func TestProcessBlock_OverMaxAttesterSlashings(t *testing.T) {
 		len(b.Block.Body.AttesterSlashings), params.BeaconConfig().MaxAttesterSlashings)
 	s, err := v1.InitializeFromProtoUnsafe(&ethpb.BeaconState{})
 	require.NoError(t, err)
-	_, err = transition.VerifyOperationLengths(context.Background(), s, wrapper.WrappedPhase0SignedBeaconBlock(b))
+	wsb, err := wrapper.WrappedSignedBeaconBlock(b)
+	require.NoError(t, err)
+	_, err = transition.VerifyOperationLengths(context.Background(), s, wsb)
 	assert.ErrorContains(t, want, err)
 }
 
@@ -429,7 +441,9 @@ func TestProcessBlock_OverMaxAttestations(t *testing.T) {
 		len(b.Block.Body.Attestations), params.BeaconConfig().MaxAttestations)
 	s, err := v1.InitializeFromProtoUnsafe(&ethpb.BeaconState{})
 	require.NoError(t, err)
-	_, err = transition.VerifyOperationLengths(context.Background(), s, wrapper.WrappedPhase0SignedBeaconBlock(b))
+	wsb, err := wrapper.WrappedSignedBeaconBlock(b)
+	require.NoError(t, err)
+	_, err = transition.VerifyOperationLengths(context.Background(), s, wsb)
 	assert.ErrorContains(t, want, err)
 }
 
@@ -446,7 +460,9 @@ func TestProcessBlock_OverMaxVoluntaryExits(t *testing.T) {
 		len(b.Block.Body.VoluntaryExits), maxExits)
 	s, err := v1.InitializeFromProtoUnsafe(&ethpb.BeaconState{})
 	require.NoError(t, err)
-	_, err = transition.VerifyOperationLengths(context.Background(), s, wrapper.WrappedPhase0SignedBeaconBlock(b))
+	wsb, err := wrapper.WrappedSignedBeaconBlock(b)
+	require.NoError(t, err)
+	_, err = transition.VerifyOperationLengths(context.Background(), s, wsb)
 	assert.ErrorContains(t, want, err)
 }
 
@@ -466,7 +482,9 @@ func TestProcessBlock_IncorrectDeposits(t *testing.T) {
 	}
 	want := fmt.Sprintf("incorrect outstanding deposits in block body, wanted: %d, got: %d",
 		s.Eth1Data().DepositCount-s.Eth1DepositIndex(), len(b.Block.Body.Deposits))
-	_, err = transition.VerifyOperationLengths(context.Background(), s, wrapper.WrappedPhase0SignedBeaconBlock(b))
+	wsb, err := wrapper.WrappedSignedBeaconBlock(b)
+	require.NoError(t, err)
+	_, err = transition.VerifyOperationLengths(context.Background(), s, wsb)
 	assert.ErrorContains(t, want, err)
 }
 

beacon-chain/db/errors.go

@@ -7,3 +7,15 @@ import "github.com/prysmaticlabs/prysm/beacon-chain/db/kv"
 // i/o error. This variable copies the value in the kv package to the same scope as the Database interfaces,
 // so that it is available to code paths that do not interact directly with the kv package.
 var ErrNotFound = kv.ErrNotFound
+
+// ErrNotFoundState wraps ErrNotFound for an error specific to a state not being found in the database.
+var ErrNotFoundState = kv.ErrNotFoundState
+
+// ErrNotFoundOriginBlockRoot wraps ErrNotFound for an error specific to the origin block root.
+var ErrNotFoundOriginBlockRoot = kv.ErrNotFoundOriginBlockRoot
+
+// ErrNotFoundOriginBlockRoot wraps ErrNotFound for an error specific to the origin block root.
+var ErrNotFoundBackfillBlockRoot = kv.ErrNotFoundBackfillBlockRoot
+
+// ErrNotFoundGenesisBlockRoot means no genesis block root was found, indicating the db was not initialized with genesis
+var ErrNotFoundGenesisBlockRoot = kv.ErrNotFoundGenesisBlockRoot

beacon-chain/db/iface/interface.go

@@ -27,12 +27,13 @@ type ReadOnlyDatabase interface {
 	BlockRootsBySlot(ctx context.Context, slot types.Slot) (bool, [][32]byte, error)
 	HasBlock(ctx context.Context, blockRoot [32]byte) bool
 	GenesisBlock(ctx context.Context) (block.SignedBeaconBlock, error)
+	GenesisBlockRoot(ctx context.Context) ([32]byte, error)
 	IsFinalizedBlock(ctx context.Context, blockRoot [32]byte) bool
 	FinalizedChildBlock(ctx context.Context, blockRoot [32]byte) (block.SignedBeaconBlock, error)
 	HighestSlotBlocksBelow(ctx context.Context, slot types.Slot) ([]block.SignedBeaconBlock, error)
-	ValidatedTips(ctx context.Context) (map[[32]byte]types.Slot, error)
 	// State related methods.
 	State(ctx context.Context, blockRoot [32]byte) (state.BeaconState, error)
+	StateOrError(ctx context.Context, blockRoot [32]byte) (state.BeaconState, error)
 	GenesisState(ctx context.Context) (state.BeaconState, error)
 	HasState(ctx context.Context, blockRoot [32]byte) bool
 	StateSummary(ctx context.Context, blockRoot [32]byte) (*ethpb.StateSummary, error)
@@ -45,13 +46,16 @@ type ReadOnlyDatabase interface {
 	HasArchivedPoint(ctx context.Context, slot types.Slot) bool
 	LastArchivedRoot(ctx context.Context) [32]byte
 	LastArchivedSlot(ctx context.Context) (types.Slot, error)
+	LastValidatedCheckpoint(ctx context.Context) (*ethpb.Checkpoint, error)
 	// Deposit contract related handlers.
 	DepositContractAddress(ctx context.Context) ([]byte, error)
 	// Powchain operations.
 	PowchainData(ctx context.Context) (*ethpb.ETH1ChainData, error)
-
+	// Fee reicipients operations.
+	FeeRecipientByValidatorID(ctx context.Context, id types.ValidatorIndex) (common.Address, error)
 	// origin checkpoint sync support
-	OriginBlockRoot(ctx context.Context) ([32]byte, error)
+	OriginCheckpointBlockRoot(ctx context.Context) ([32]byte, error)
+	BackfillBlockRoot(ctx context.Context) ([32]byte, error)
 }
 
 // NoHeadAccessDatabase defines a struct without access to chain head data.
@@ -63,7 +67,6 @@ type NoHeadAccessDatabase interface {
 	SaveBlock(ctx context.Context, block block.SignedBeaconBlock) error
 	SaveBlocks(ctx context.Context, blocks []block.SignedBeaconBlock) error
 	SaveGenesisBlockRoot(ctx context.Context, blockRoot [32]byte) error
-	UpdateValidatedTips(ctx context.Context, newVals map[[32]byte]types.Slot) error
 	// State related methods.
 	SaveState(ctx context.Context, state state.ReadOnlyBeaconState, blockRoot [32]byte) error
 	SaveStates(ctx context.Context, states []state.ReadOnlyBeaconState, blockRoots [][32]byte) error
@@ -74,12 +77,15 @@ type NoHeadAccessDatabase interface {
 	// Checkpoint operations.
 	SaveJustifiedCheckpoint(ctx context.Context, checkpoint *ethpb.Checkpoint) error
 	SaveFinalizedCheckpoint(ctx context.Context, checkpoint *ethpb.Checkpoint) error
+	SaveLastValidatedCheckpoint(ctx context.Context, checkpoint *ethpb.Checkpoint) error
 	// Deposit contract related handlers.
 	SaveDepositContractAddress(ctx context.Context, addr common.Address) error
 	// Powchain operations.
 	SavePowchainData(ctx context.Context, data *ethpb.ETH1ChainData) error
 	// Run any required database migrations.
 	RunMigrations(ctx context.Context) error
+	// Fee reicipients operations.
+	SaveFeeRecipientsByValidatorIDs(ctx context.Context, ids []types.ValidatorIndex, addrs []common.Address) error
 
 	CleanUpDirtyStates(ctx context.Context, slotsPerArchivedPoint types.Slot) error
 }
@@ -98,7 +104,8 @@ type HeadAccessDatabase interface {
 	EnsureEmbeddedGenesis(ctx context.Context) error
 
 	// initialization method needed for origin checkpoint sync
-	SaveOrigin(ctx context.Context, state io.Reader, block io.Reader) error
+	SaveOrigin(ctx context.Context, serState, serBlock []byte) error
+	SaveBackfillBlockRoot(ctx context.Context, blockRoot [32]byte) error
 }
 
 // SlasherDatabase interface for persisting data related to detecting slashable offenses on Ethereum.

beacon-chain/db/kv/BUILD.bazel

@@ -25,7 +25,7 @@ go_library(
         "state_summary.go",
         "state_summary_cache.go",
         "utils.go",
-        "validated_tips.go",
+        "validated_checkpoint.go",
         "wss.go",
     ],
     importpath = "github.com/prysmaticlabs/prysm/beacon-chain/db/kv",
@@ -47,6 +47,7 @@ go_library(
         "//config/params:go_default_library",
         "//container/slice:go_default_library",
         "//encoding/bytesutil:go_default_library",
+        "//encoding/ssz/detect:go_default_library",
         "//io/file:go_default_library",
         "//monitoring/progress:go_default_library",
         "//monitoring/tracing:go_default_library",
@@ -81,7 +82,6 @@ go_test(
         "checkpoint_test.go",
         "deposit_contract_test.go",
         "encoding_test.go",
-        "error_test.go",
         "finalized_block_roots_test.go",
         "genesis_test.go",
         "init_test.go",
@@ -93,7 +93,7 @@ go_test(
         "state_summary_test.go",
         "state_test.go",
         "utils_test.go",
-        "validated_tips_test.go",
+        "validated_checkpoint_test.go",
     ],
     data = glob(["testdata/**"]),
     embed = [":go_default_library"],
@@ -116,6 +116,7 @@ go_test(
         "//testing/util:go_default_library",
         "@com_github_ethereum_go_ethereum//common:go_default_library",
         "@com_github_golang_snappy//:go_default_library",
+        "@com_github_pkg_errors//:go_default_library",
         "@com_github_prysmaticlabs_eth2_types//:go_default_library",
         "@io_bazel_rules_go//go/tools/bazel:go_default_library",
         "@io_etcd_go_bbolt//:go_default_library",

beacon-chain/db/kv/backup_test.go

@@ -21,7 +21,9 @@ func TestStore_Backup(t *testing.T) {
 	head := util.NewBeaconBlock()
 	head.Block.Slot = 5000
 
-	require.NoError(t, db.SaveBlock(ctx, wrapper.WrappedPhase0SignedBeaconBlock(head)))
+	wsb, err := wrapper.WrappedSignedBeaconBlock(head)
+	require.NoError(t, err)
+	require.NoError(t, db.SaveBlock(ctx, wsb))
 	root, err := head.Block.HashTreeRoot()
 	require.NoError(t, err)
 	st, err := util.NewBeaconState()
@@ -61,7 +63,9 @@ func TestStore_BackupMultipleBuckets(t *testing.T) {
 	for i := startSlot; i < 5200; i++ {
 		head := util.NewBeaconBlock()
 		head.Block.Slot = i
-		require.NoError(t, db.SaveBlock(ctx, wrapper.WrappedPhase0SignedBeaconBlock(head)))
+		wsb, err := wrapper.WrappedSignedBeaconBlock(head)
+		require.NoError(t, err)
+		require.NoError(t, db.SaveBlock(ctx, wsb))
 		root, err := head.Block.HashTreeRoot()
 		require.NoError(t, err)
 		st, err := util.NewBeaconState()

beacon-chain/db/kv/blocks.go

@@ -5,6 +5,8 @@ import (
 	"context"
 	"fmt"
 
+	"github.com/ethereum/go-ethereum/common"
+	ssz "github.com/ferranbt/fastssz"
 	"github.com/golang/snappy"
 	"github.com/pkg/errors"
 	types "github.com/prysmaticlabs/eth2-types"
@@ -46,18 +48,18 @@ func (s *Store) Block(ctx context.Context, blockRoot [32]byte) (block.SignedBeac
 	return blk, err
 }
 
-// OriginBlockRoot returns the value written to the db in SaveOriginBlockRoot
+// OriginCheckpointBlockRoot returns the value written to the db in SaveOriginCheckpointBlockRoot
 // This is the root of a finalized block within the weak subjectivity period
 // at the time the chain was started, used to initialize the database and chain
 // without syncing from genesis.
-func (s *Store) OriginBlockRoot(ctx context.Context) ([32]byte, error) {
-	_, span := trace.StartSpan(ctx, "BeaconDB.OriginBlockRoot")
+func (s *Store) OriginCheckpointBlockRoot(ctx context.Context) ([32]byte, error) {
+	_, span := trace.StartSpan(ctx, "BeaconDB.OriginCheckpointBlockRoot")
 	defer span.End()
 
 	var root [32]byte
 	err := s.db.View(func(tx *bolt.Tx) error {
 		bkt := tx.Bucket(blocksBucket)
-		rootSlice := bkt.Get(originBlockRootKey)
+		rootSlice := bkt.Get(originCheckpointBlockRootKey)
 		if rootSlice == nil {
 			return ErrNotFoundOriginBlockRoot
 		}
@@ -68,6 +70,25 @@ func (s *Store) OriginBlockRoot(ctx context.Context) ([32]byte, error) {
 	return root, err
 }
 
+// BackfillBlockRoot keeps track of the highest block available before the OriginCheckpointBlockRoot
+func (s *Store) BackfillBlockRoot(ctx context.Context) ([32]byte, error) {
+	_, span := trace.StartSpan(ctx, "BeaconDB.BackfillBlockRoot")
+	defer span.End()
+
+	var root [32]byte
+	err := s.db.View(func(tx *bolt.Tx) error {
+		bkt := tx.Bucket(blocksBucket)
+		rootSlice := bkt.Get(backfillBlockRootKey)
+		if len(rootSlice) == 0 {
+			return ErrNotFoundBackfillBlockRoot
+		}
+		root = bytesutil.ToBytes32(rootSlice)
+		return nil
+	})
+
+	return root, err
+}
+
 // HeadBlock returns the latest canonical block in the Ethereum Beacon Chain.
 func (s *Store) HeadBlock(ctx context.Context) (block.SignedBeaconBlock, error) {
 	ctx, span := trace.StartSpan(ctx, "BeaconDB.HeadBlock")
@@ -323,6 +344,22 @@ func (s *Store) GenesisBlock(ctx context.Context) (block.SignedBeaconBlock, erro
 	return blk, err
 }
 
+func (s *Store) GenesisBlockRoot(ctx context.Context) ([32]byte, error) {
+	ctx, span := trace.StartSpan(ctx, "BeaconDB.GenesisBlockRoot")
+	defer span.End()
+	var root [32]byte
+	err := s.db.View(func(tx *bolt.Tx) error {
+		bkt := tx.Bucket(blocksBucket)
+		r := bkt.Get(genesisBlockRootKey)
+		if len(r) == 0 {
+			return ErrNotFoundGenesisBlockRoot
+		}
+		root = bytesutil.ToBytes32(r)
+		return nil
+	})
+	return root, err
+}
+
 // SaveGenesisBlockRoot to the db.
 func (s *Store) SaveGenesisBlockRoot(ctx context.Context, blockRoot [32]byte) error {
 	_, span := trace.StartSpan(ctx, "BeaconDB.SaveGenesisBlockRoot")
@@ -333,16 +370,27 @@ func (s *Store) SaveGenesisBlockRoot(ctx context.Context, blockRoot [32]byte) er
 	})
 }
 
-// SaveOriginBlockRoot is used to keep track of the block root used for origin sync.
+// SaveOriginCheckpointBlockRoot is used to keep track of the block root used for syncing from a checkpoint origin.
 // This should be a finalized block from within the current weak subjectivity period.
 // This value is used by a running beacon chain node to locate the state at the beginning
 // of the chain history, in places where genesis would typically be used.
-func (s *Store) SaveOriginBlockRoot(ctx context.Context, blockRoot [32]byte) error {
-	_, span := trace.StartSpan(ctx, "BeaconDB.SaveOriginBlockRoot")
+func (s *Store) SaveOriginCheckpointBlockRoot(ctx context.Context, blockRoot [32]byte) error {
+	_, span := trace.StartSpan(ctx, "BeaconDB.SaveOriginCheckpointBlockRoot")
 	defer span.End()
 	return s.db.Update(func(tx *bolt.Tx) error {
 		bucket := tx.Bucket(blocksBucket)
-		return bucket.Put(originBlockRootKey, blockRoot[:])
+		return bucket.Put(originCheckpointBlockRootKey, blockRoot[:])
+	})
+}
+
+// SaveBackfillBlockRoot is used to keep track of the most recently backfilled block root when
+// the node was initialized via checkpoint sync.
+func (s *Store) SaveBackfillBlockRoot(ctx context.Context, blockRoot [32]byte) error {
+	_, span := trace.StartSpan(ctx, "BeaconDB.SaveBackfillBlockRoot")
+	defer span.End()
+	return s.db.Update(func(tx *bolt.Tx) error {
+		bucket := tx.Bucket(blocksBucket)
+		return bucket.Put(backfillBlockRootKey, blockRoot[:])
 	})
 }
 
@@ -392,6 +440,44 @@ func (s *Store) HighestSlotBlocksBelow(ctx context.Context, slot types.Slot) ([]
 	return []block.SignedBeaconBlock{blk}, nil
 }
 
+// FeeRecipientByValidatorID returns the fee recipient for a validator id.
+// `ErrNotFoundFeeRecipient` is returned if the validator id is not found.
+func (s *Store) FeeRecipientByValidatorID(ctx context.Context, id types.ValidatorIndex) (common.Address, error) {
+	ctx, span := trace.StartSpan(ctx, "BeaconDB.FeeRecipientByValidatorID")
+	defer span.End()
+	var addr []byte
+	err := s.db.View(func(tx *bolt.Tx) error {
+		bkt := tx.Bucket(feeRecipientBucket)
+		addr = bkt.Get(bytesutil.Uint64ToBytesBigEndian(uint64(id)))
+		if addr == nil {
+			return errors.Wrapf(ErrNotFoundFeeRecipient, "validator id %d", id)
+		}
+		return nil
+	})
+	return common.BytesToAddress(addr), err
+}
+
+// SaveFeeRecipientsByValidatorIDs saves the fee recipients for validator ids.
+// Error is returned if `ids` and `recipients` are not the same length.
+func (s *Store) SaveFeeRecipientsByValidatorIDs(ctx context.Context, ids []types.ValidatorIndex, feeRecipients []common.Address) error {
+	_, span := trace.StartSpan(ctx, "BeaconDB.SaveFeeRecipientByValidatorID")
+	defer span.End()
+
+	if len(ids) != len(feeRecipients) {
+		return errors.New("validatorIDs and feeRecipients must be the same length")
+	}
+
+	return s.db.Update(func(tx *bolt.Tx) error {
+		bkt := tx.Bucket(feeRecipientBucket)
+		for i, id := range ids {
+			if err := bkt.Put(bytesutil.Uint64ToBytesBigEndian(uint64(id)), feeRecipients[i].Bytes()); err != nil {
+				return err
+			}
+		}
+		return nil
+	})
+}
+
 // blockRootsByFilter retrieves the block roots given the filter criteria.
 func blockRootsByFilter(ctx context.Context, tx *bolt.Tx, f *filters.QueryFilter) ([][]byte, error) {
 	ctx, span := trace.StartSpan(ctx, "BeaconDB.blockRootsByFilter")
@@ -602,31 +688,27 @@ func unmarshalBlock(_ context.Context, enc []byte) (block.SignedBeaconBlock, err
 	if err != nil {
 		return nil, err
 	}
+	var rawBlock ssz.Unmarshaler
 	switch {
 	case hasAltairKey(enc):
 		// Marshal block bytes to altair beacon block.
-		rawBlock := &ethpb.SignedBeaconBlockAltair{}
-		err := rawBlock.UnmarshalSSZ(enc[len(altairKey):])
-		if err != nil {
+		rawBlock = &ethpb.SignedBeaconBlockAltair{}
+		if err := rawBlock.UnmarshalSSZ(enc[len(altairKey):]); err != nil {
 			return nil, err
 		}
-		return wrapper.WrappedAltairSignedBeaconBlock(rawBlock)
 	case hasBellatrixKey(enc):
-		rawBlock := &ethpb.SignedBeaconBlockBellatrix{}
-		err := rawBlock.UnmarshalSSZ(enc[len(bellatrixKey):])
-		if err != nil {
+		rawBlock = &ethpb.SignedBeaconBlockBellatrix{}
+		if err := rawBlock.UnmarshalSSZ(enc[len(bellatrixKey):]); err != nil {
 			return nil, err
 		}
-		return wrapper.WrappedBellatrixSignedBeaconBlock(rawBlock)
 	default:
 		// Marshal block bytes to phase 0 beacon block.
-		rawBlock := &ethpb.SignedBeaconBlock{}
-		err = rawBlock.UnmarshalSSZ(enc)
-		if err != nil {
+		rawBlock = &ethpb.SignedBeaconBlock{}
+		if err := rawBlock.UnmarshalSSZ(enc); err != nil {
 			return nil, err
 		}
-		return wrapper.WrappedPhase0SignedBeaconBlock(rawBlock), nil
 	}
+	return wrapper.WrappedSignedBeaconBlock(rawBlock)
 }
 
 // marshal versioned beacon block from struct type down to bytes.

beacon-chain/db/kv/blocks_test.go

@@ -4,6 +4,8 @@ import (
 	"context"
 	"testing"
 
+	"github.com/ethereum/go-ethereum/common"
+	"github.com/pkg/errors"
 	types "github.com/prysmaticlabs/eth2-types"
 	"github.com/prysmaticlabs/prysm/beacon-chain/db/filters"
 	"github.com/prysmaticlabs/prysm/config/params"
@@ -29,7 +31,7 @@ var blockTests = []struct {
 			if root != nil {
 				b.Block.ParentRoot = root
 			}
-			return wrapper.WrappedPhase0SignedBeaconBlock(b), nil
+			return wrapper.WrappedSignedBeaconBlock(b)
 		},
 	},
 	{
@@ -40,7 +42,7 @@ var blockTests = []struct {
 			if root != nil {
 				b.Block.ParentRoot = root
 			}
-			return wrapper.WrappedAltairSignedBeaconBlock(b)
+			return wrapper.WrappedSignedBeaconBlock(b)
 		},
 	},
 	{
@@ -51,11 +53,28 @@ var blockTests = []struct {
 			if root != nil {
 				b.Block.ParentRoot = root
 			}
-			return wrapper.WrappedBellatrixSignedBeaconBlock(b)
+			return wrapper.WrappedSignedBeaconBlock(b)
 		},
 	},
 }
 
+func TestStore_SaveBackfillBlockRoot(t *testing.T) {
+	db := setupDB(t)
+	ctx := context.Background()
+
+	_, err := db.BackfillBlockRoot(ctx)
+	require.ErrorIs(t, err, ErrNotFoundBackfillBlockRoot)
+
+	expected := [32]byte{}
+	copy(expected[:], []byte{0x23})
+	err = db.SaveBackfillBlockRoot(ctx, expected)
+	require.NoError(t, err)
+	actual, err := db.BackfillBlockRoot(ctx)
+	require.NoError(t, err)
+	require.Equal(t, expected, actual)
+
+}
+
 func TestStore_SaveBlock_NoDuplicates(t *testing.T) {
 	BlockCacheSize = 1
 	slot := types.Slot(20)
@@ -210,7 +229,9 @@ func TestStore_GenesisBlock(t *testing.T) {
 	blockRoot, err := genesisBlock.Block.HashTreeRoot()
 	require.NoError(t, err)
 	require.NoError(t, db.SaveGenesisBlockRoot(ctx, blockRoot))
-	require.NoError(t, db.SaveBlock(ctx, wrapper.WrappedPhase0SignedBeaconBlock(genesisBlock)))
+	wsb, err := wrapper.WrappedSignedBeaconBlock(genesisBlock)
+	require.NoError(t, err)
+	require.NoError(t, db.SaveBlock(ctx, wsb))
 	retrievedBlock, err := db.GenesisBlock(ctx)
 	require.NoError(t, err)
 	assert.Equal(t, true, proto.Equal(genesisBlock, retrievedBlock.Proto()), "Wanted: %v, received: %v", genesisBlock, retrievedBlock)
@@ -589,3 +610,27 @@ func TestStore_BlocksBySlot_BlockRootsBySlot(t *testing.T) {
 		})
 	}
 }
+
+func TestStore_FeeRecipientByValidatorID(t *testing.T) {
+	db := setupDB(t)
+	ctx := context.Background()
+	ids := []types.ValidatorIndex{0, 0, 0}
+	feeRecipients := []common.Address{{}, {}, {}, {}}
+	require.ErrorContains(t, "validatorIDs and feeRecipients must be the same length", db.SaveFeeRecipientsByValidatorIDs(ctx, ids, feeRecipients))
+
+	ids = []types.ValidatorIndex{0, 1, 2}
+	feeRecipients = []common.Address{{'a'}, {'b'}, {'c'}}
+	require.NoError(t, db.SaveFeeRecipientsByValidatorIDs(ctx, ids, feeRecipients))
+	f, err := db.FeeRecipientByValidatorID(ctx, 0)
+	require.NoError(t, err)
+	require.Equal(t, common.Address{'a'}, f)
+	f, err = db.FeeRecipientByValidatorID(ctx, 1)
+	require.NoError(t, err)
+	require.Equal(t, common.Address{'b'}, f)
+	f, err = db.FeeRecipientByValidatorID(ctx, 2)
+	require.NoError(t, err)
+	require.Equal(t, common.Address{'c'}, f)
+	_, err = db.FeeRecipientByValidatorID(ctx, 3)
+	want := errors.Wrap(ErrNotFoundFeeRecipient, "validator id 3")
+	require.Equal(t, want.Error(), err.Error())
+}

beacon-chain/db/kv/checkpoint_test.go

@@ -53,7 +53,9 @@ func TestStore_FinalizedCheckpoint_CanSaveRetrieve(t *testing.T) {
 	}
 
 	// a valid chain is required to save finalized checkpoint.
-	require.NoError(t, db.SaveBlock(ctx, wrapper.WrappedPhase0SignedBeaconBlock(blk)))
+	wsb, err := wrapper.WrappedSignedBeaconBlock(blk)
+	require.NoError(t, err)
+	require.NoError(t, db.SaveBlock(ctx, wsb))
 	st, err := util.NewBeaconState()
 	require.NoError(t, err)
 	require.NoError(t, st.SetSlot(1))

beacon-chain/db/kv/error.go

@@ -1,6 +1,6 @@
 package kv
 
-import "errors"
+import "github.com/pkg/errors"
 
 // errDeleteFinalized is raised when we attempt to delete a finalized block/state
 var errDeleteFinalized = errors.New("cannot delete finalized block or state")
@@ -8,42 +8,16 @@ var errDeleteFinalized = errors.New("cannot delete finalized block or state")
 // ErrNotFound can be used directly, or as a wrapped DBError, whenever a db method needs to
 // indicate that a value couldn't be found.
 var ErrNotFound = errors.New("not found in db")
+var ErrNotFoundState = errors.Wrap(ErrNotFound, "state not found")
 
 // ErrNotFoundOriginBlockRoot is an error specifically for the origin block root getter
-var ErrNotFoundOriginBlockRoot = WrapDBError(ErrNotFound, "OriginBlockRoot")
+var ErrNotFoundOriginBlockRoot = errors.Wrap(ErrNotFound, "OriginBlockRoot")
 
-// WrapDBError wraps an error in a DBError. See commentary on DBError for more context.
-func WrapDBError(e error, outer string) error {
-	return DBError{
-		Wraps: e,
-		Outer: errors.New(outer),
-	}
-}
+// ErrNotFoundGenesisBlockRoot means no genesis block root was found, indicating the db was not initialized with genesis
+var ErrNotFoundGenesisBlockRoot = errors.Wrap(ErrNotFound, "OriginGenesisRoot")
 
-// DBError implements the Error method so that it can be asserted as an error.
-// The Unwrap method supports error wrapping, enabling it to be used with errors.Is/As.
-// The primary use case is to make it simple for database methods to return errors
-// that wrap ErrNotFound, allowing calling code to check for "not found" errors
-// like: `error.Is(err, ErrNotFound)`. This is intended to improve error handling
-// in db lookup methods that need to differentiate between a missing value and some
-// other database error. for more background see:
-// https://go.dev/blog/go1.13-errors
-type DBError struct {
-	Wraps error
-	Outer error
-}
+// ErrNotFoundOriginBlockRoot is an error specifically for the origin block root getter
+var ErrNotFoundBackfillBlockRoot = errors.Wrap(ErrNotFound, "BackfillBlockRoot")
 
-// Error satisfies the error interface, so that DBErrors can be used anywhere that
-// expects an `error`.
-func (e DBError) Error() string {
-	es := e.Outer.Error()
-	if e.Wraps != nil {
-		es += ": " + e.Wraps.Error()
-	}
-	return es
-}
-
-// Unwrap is used by the errors package Is and As methods.
-func (e DBError) Unwrap() error {
-	return e.Wraps
-}
+// ErrNotFoundFeeRecipient is a not found error specifically for the fee recipient getter
+var ErrNotFoundFeeRecipient = errors.Wrap(ErrNotFound, "fee recipient")

beacon-chain/db/kv/error_test.go

@@ -1,24 +0,0 @@
-package kv
-
-import (
-	"errors"
-	"testing"
-)
-
-func TestWrappedSentinelError(t *testing.T) {
-	e := ErrNotFoundOriginBlockRoot
-	if !errors.Is(e, ErrNotFoundOriginBlockRoot) {
-		t.Error("expected that a copy of ErrNotFoundOriginBlockRoot would have an is-a relationship")
-	}
-
-	outer := errors.New("wrapped error")
-	e2 := DBError{Wraps: ErrNotFoundOriginBlockRoot, Outer: outer}
-	if !errors.Is(e2, ErrNotFoundOriginBlockRoot) {
-		t.Error("expected that errors.Is would know DBError wraps ErrNotFoundOriginBlockRoot")
-	}
-
-	// test that the innermost not found error is detected
-	if !errors.Is(e2, ErrNotFound) {
-		t.Error("expected that errors.Is would know ErrNotFoundOriginBlockRoot wraps ErrNotFound")
-	}
-}

beacon-chain/db/kv/finalized_block_roots.go

@@ -32,7 +32,7 @@ var containerFinalizedButNotCanonical = []byte("recent block needs reindexing to
 //   - De-index all finalized beacon block roots from previous_finalized_epoch to
 //     new_finalized_epoch. (I.e. delete these roots from the index, to be re-indexed.)
 //   - Build the canonical finalized chain by walking up the ancestry chain from the finalized block
-//     root until a parent is found in the index or the parent is genesis.
+//     root until a parent is found in the index, or the parent is genesis or the origin checkpoint.
 //   - Add all block roots in the database where epoch(block.slot) == checkpoint.epoch.
 //
 // This method ensures that all blocks from the current finalized epoch are considered "final" while
@@ -46,6 +46,7 @@ func (s *Store) updateFinalizedBlockRoots(ctx context.Context, tx *bolt.Tx, chec
 	root := checkpoint.Root
 	var previousRoot []byte
 	genesisRoot := tx.Bucket(blocksBucket).Get(genesisBlockRootKey)
+	initCheckpointRoot := tx.Bucket(blocksBucket).Get(originCheckpointBlockRootKey)
 
 	// De-index recent finalized block roots, to be re-indexed.
 	previousFinalizedCheckpoint := &ethpb.Checkpoint{}
@@ -74,7 +75,7 @@ func (s *Store) updateFinalizedBlockRoots(ctx context.Context, tx *bolt.Tx, chec
 	// Walk up the ancestry chain until we reach a block root present in the finalized block roots
 	// index bucket or genesis block root.
 	for {
-		if bytes.Equal(root, genesisRoot) {
+		if bytes.Equal(root, genesisRoot) || bytes.Equal(root, initCheckpointRoot) {
 			break
 		}
 

beacon-chain/db/kv/finalized_block_roots_test.go

@@ -63,7 +63,9 @@ func TestStore_IsFinalizedBlockGenesis(t *testing.T) {
 	blk.Block.Slot = 0
 	root, err := blk.Block.HashTreeRoot()
 	require.NoError(t, err)
-	require.NoError(t, db.SaveBlock(ctx, wrapper.WrappedPhase0SignedBeaconBlock(blk)))
+	wsb, err := wrapper.WrappedSignedBeaconBlock(blk)
+	require.NoError(t, err)
+	require.NoError(t, db.SaveBlock(ctx, wsb))
 	require.NoError(t, db.SaveGenesisBlockRoot(ctx, root))
 	assert.Equal(t, true, db.IsFinalizedBlock(ctx, root), "Finalized genesis block doesn't exist in db")
 }
@@ -207,7 +209,8 @@ func makeBlocks(t *testing.T, i, n uint64, previousRoot [32]byte) []block.Signed
 		var err error
 		previousRoot, err = blocks[j-i].Block.HashTreeRoot()
 		require.NoError(t, err)
-		ifaceBlocks[j-i] = wrapper.WrappedPhase0SignedBeaconBlock(blocks[j-i])
+		ifaceBlocks[j-i], err = wrapper.WrappedSignedBeaconBlock(blocks[j-i])
+		require.NoError(t, err)
 	}
 	return ifaceBlocks
 }
@@ -224,7 +227,7 @@ func makeBlocksAltair(t *testing.T, startIdx, num uint64, previousRoot [32]byte)
 		var err error
 		previousRoot, err = blocks[j-startIdx].Block.HashTreeRoot()
 		require.NoError(t, err)
-		ifaceBlocks[j-startIdx], err = wrapper.WrappedAltairSignedBeaconBlock(blocks[j-startIdx])
+		ifaceBlocks[j-startIdx], err = wrapper.WrappedSignedBeaconBlock(blocks[j-startIdx])
 		require.NoError(t, err)
 	}
 	return ifaceBlocks

beacon-chain/db/kv/genesis.go

@@ -28,7 +28,11 @@ func (s *Store) SaveGenesisData(ctx context.Context, genesisState state.BeaconSt
 	if err != nil {
 		return errors.Wrap(err, "could not get genesis block root")
 	}
-	if err := s.SaveBlock(ctx, wrapper.WrappedPhase0SignedBeaconBlock(genesisBlk)); err != nil {
+	wsb, err := wrapper.WrappedSignedBeaconBlock(genesisBlk)
+	if err != nil {
+		return errors.Wrap(err, "could not wrap genesis block")
+	}
+	if err := s.SaveBlock(ctx, wsb); err != nil {
 		return errors.Wrap(err, "could not save genesis block")
 	}
 	if err := s.SaveState(ctx, genesisState, genesisBlkRoot); err != nil {

beacon-chain/db/kv/kv.go

@@ -175,7 +175,6 @@ func NewKVStore(ctx context.Context, dirPath string, config *Config) (*Store, er
 			powchainBucket,
 			stateSummaryBucket,
 			stateValidatorsBucket,
-			validatedTips,
 			// Indices buckets.
 			attestationHeadBlockRootBucket,
 			attestationSourceRootIndicesBucket,
@@ -191,6 +190,8 @@ func NewKVStore(ctx context.Context, dirPath string, config *Config) (*Store, er
 			newStateServiceCompatibleBucket,
 			// Migrations
 			migrationsBucket,
+
+			feeRecipientBucket,
 		)
 	}); err != nil {
 		log.WithField("elapsed", time.Since(start)).Error("Failed to update db and create buckets")

beacon-chain/db/kv/schema.go

@@ -18,7 +18,7 @@ var (
 	checkpointBucket        = []byte("check-point")
 	powchainBucket          = []byte("powchain")
 	stateValidatorsBucket   = []byte("state-validators")
-	validatedTips           = []byte("validated-synced-tips")
+	feeRecipientBucket      = []byte("fee-recipient")
 
 	// Deprecated: This bucket was migrated in PR 6461. Do not use, except for migrations.
 	slotsHasObjectBucket = []byte("slots-has-objects")
@@ -38,19 +38,22 @@ var (
 	blockRootValidatorHashesBucket      = []byte("block-root-validator-hashes")
 
 	// Specific item keys.
-	headBlockRootKey          = []byte("head-root")
-	genesisBlockRootKey       = []byte("genesis-root")
-	depositContractAddressKey = []byte("deposit-contract")
-	justifiedCheckpointKey    = []byte("justified-checkpoint")
-	finalizedCheckpointKey    = []byte("finalized-checkpoint")
-	powchainDataKey           = []byte("powchain-data")
+	headBlockRootKey           = []byte("head-root")
+	genesisBlockRootKey        = []byte("genesis-root")
+	depositContractAddressKey  = []byte("deposit-contract")
+	justifiedCheckpointKey     = []byte("justified-checkpoint")
+	finalizedCheckpointKey     = []byte("finalized-checkpoint")
+	powchainDataKey            = []byte("powchain-data")
+	lastValidatedCheckpointKey = []byte("last-validated-checkpoint")
 
 	// Below keys are used to identify objects are to be fork compatible.
 	// Objects that are only compatible with specific forks should be prefixed with such keys.
 	altairKey    = []byte("altair")
 	bellatrixKey = []byte("merge")
 	// block root included in the beacon state used by weak subjectivity initial sync
-	originBlockRootKey = []byte("origin-block-root")
+	originCheckpointBlockRootKey = []byte("origin-checkpoint-block-root")
+	// block root tracking the progress of backfill, or pointing at genesis if backfill has not been initiated
+	backfillBlockRootKey = []byte("backfill-block-root")
 
 	// Deprecated: This index key was migrated in PR 6461. Do not use, except for migrations.
 	lastArchivedIndexKey = []byte("last-archived")

beacon-chain/db/kv/state.go

@@ -3,6 +3,7 @@ package kv
 import (
 	"bytes"
 	"context"
+	"fmt"
 
 	"github.com/golang/snappy"
 	"github.com/pkg/errors"
@@ -46,6 +47,19 @@ func (s *Store) State(ctx context.Context, blockRoot [32]byte) (state.BeaconStat
 	return s.unmarshalState(ctx, enc, valEntries)
 }
 
+// StateOrError is just like State(), except it only returns a non-error response
+// if the requested state is found in the database.
+func (s *Store) StateOrError(ctx context.Context, blockRoot [32]byte) (state.BeaconState, error) {
+	st, err := s.State(ctx, blockRoot)
+	if err != nil {
+		return nil, err
+	}
+	if st == nil || st.IsNil() {
+		return nil, errors.Wrap(ErrNotFoundState, fmt.Sprintf("no state with blockroot=%#x", blockRoot))
+	}
+	return st, nil
+}
+
 // GenesisState returns the genesis state in beacon chain.
 func (s *Store) GenesisState(ctx context.Context) (state.BeaconState, error) {
 	ctx, span := trace.StartSpan(ctx, "BeaconDB.GenesisState")
@@ -624,7 +638,11 @@ func (s *Store) slotByBlockRoot(ctx context.Context, tx *bolt.Tx, blockRoot []by
 		if err != nil {
 			return 0, err
 		}
-		if err := helpers.BeaconBlockIsNil(wrapper.WrappedPhase0SignedBeaconBlock(b)); err != nil {
+		wsb, err := wrapper.WrappedSignedBeaconBlock(b)
+		if err != nil {
+			return 0, err
+		}
+		if err := helpers.BeaconBlockIsNil(wsb); err != nil {
 			return 0, err
 		}
 		return b.Block.Slot, nil

beacon-chain/db/kv/state_test.go

@@ -21,6 +21,12 @@ import (
 	bolt "go.etcd.io/bbolt"
 )
 
+func TestStateNil(t *testing.T) {
+	db := setupDB(t)
+	_, err := db.StateOrError(context.Background(), [32]byte{})
+	require.ErrorIs(t, err, ErrNotFoundState)
+}
+
 func TestState_CanSaveRetrieve(t *testing.T) {
 	db := setupDB(t)
 
@@ -368,7 +374,9 @@ func TestStore_StatesBatchDelete(t *testing.T) {
 	for i := 0; i < len(totalBlocks); i++ {
 		b := util.NewBeaconBlock()
 		b.Block.Slot = types.Slot(i)
-		totalBlocks[i] = wrapper.WrappedPhase0SignedBeaconBlock(b)
+		var err error
+		totalBlocks[i], err = wrapper.WrappedSignedBeaconBlock(b)
+		require.NoError(t, err)
 		r, err := totalBlocks[i].Block().HashTreeRoot()
 		require.NoError(t, err)
 		st, err := util.NewBeaconState()
@@ -419,7 +427,9 @@ func TestStore_DeleteFinalizedState(t *testing.T) {
 	blk.Block.ParentRoot = genesis[:]
 	blk.Block.Slot = 100
 
-	require.NoError(t, db.SaveBlock(ctx, wrapper.WrappedPhase0SignedBeaconBlock(blk)))
+	wsb, err := wrapper.WrappedSignedBeaconBlock(blk)
+	require.NoError(t, err)
+	require.NoError(t, db.SaveBlock(ctx, wsb))
 
 	finalizedBlockRoot, err := blk.Block.HashTreeRoot()
 	require.NoError(t, err)
@@ -444,7 +454,9 @@ func TestStore_DeleteHeadState(t *testing.T) {
 	blk := util.NewBeaconBlock()
 	blk.Block.ParentRoot = genesis[:]
 	blk.Block.Slot = 100
-	require.NoError(t, db.SaveBlock(ctx, wrapper.WrappedPhase0SignedBeaconBlock(blk)))
+	wsb, err := wrapper.WrappedSignedBeaconBlock(blk)
+	require.NoError(t, err)
+	require.NoError(t, db.SaveBlock(ctx, wsb))
 
 	headBlockRoot, err := blk.Block.HashTreeRoot()
 	require.NoError(t, err)
@@ -464,7 +476,9 @@ func TestStore_SaveDeleteState_CanGetHighestBelow(t *testing.T) {
 	b.Block.Slot = 1
 	r, err := b.Block.HashTreeRoot()
 	require.NoError(t, err)
-	require.NoError(t, db.SaveBlock(context.Background(), wrapper.WrappedPhase0SignedBeaconBlock(b)))
+	wsb, err := wrapper.WrappedSignedBeaconBlock(b)
+	require.NoError(t, err)
+	require.NoError(t, db.SaveBlock(context.Background(), wsb))
 	st, err := util.NewBeaconState()
 	require.NoError(t, err)
 	require.NoError(t, st.SetSlot(1))
@@ -474,7 +488,9 @@ func TestStore_SaveDeleteState_CanGetHighestBelow(t *testing.T) {
 	b.Block.Slot = 100
 	r1, err := b.Block.HashTreeRoot()
 	require.NoError(t, err)
-	require.NoError(t, db.SaveBlock(context.Background(), wrapper.WrappedPhase0SignedBeaconBlock(b)))
+	wsb, err = wrapper.WrappedSignedBeaconBlock(b)
+	require.NoError(t, err)
+	require.NoError(t, db.SaveBlock(context.Background(), wsb))
 	st, err = util.NewBeaconState()
 	require.NoError(t, err)
 	require.NoError(t, st.SetSlot(100))
@@ -484,7 +500,9 @@ func TestStore_SaveDeleteState_CanGetHighestBelow(t *testing.T) {
 	b.Block.Slot = 1000
 	r2, err := b.Block.HashTreeRoot()
 	require.NoError(t, err)
-	require.NoError(t, db.SaveBlock(context.Background(), wrapper.WrappedPhase0SignedBeaconBlock(b)))
+	wsb, err = wrapper.WrappedSignedBeaconBlock(b)
+	require.NoError(t, err)
+	require.NoError(t, db.SaveBlock(context.Background(), wsb))
 	st, err = util.NewBeaconState()
 	require.NoError(t, err)
 	require.NoError(t, st.SetSlot(1000))
@@ -518,7 +536,9 @@ func TestStore_GenesisState_CanGetHighestBelow(t *testing.T) {
 	b.Block.Slot = 1
 	r, err := b.Block.HashTreeRoot()
 	require.NoError(t, err)
-	require.NoError(t, db.SaveBlock(context.Background(), wrapper.WrappedPhase0SignedBeaconBlock(b)))
+	wsb, err := wrapper.WrappedSignedBeaconBlock(b)
+	require.NoError(t, err)
+	require.NoError(t, db.SaveBlock(context.Background(), wsb))
 
 	st, err := util.NewBeaconState()
 	require.NoError(t, err)
@@ -555,7 +575,9 @@ func TestStore_CleanUpDirtyStates_AboveThreshold(t *testing.T) {
 		b.Block.ParentRoot = prevRoot[:]
 		r, err := b.Block.HashTreeRoot()
 		require.NoError(t, err)
-		require.NoError(t, db.SaveBlock(context.Background(), wrapper.WrappedPhase0SignedBeaconBlock(b)))
+		wsb, err := wrapper.WrappedSignedBeaconBlock(b)
+		require.NoError(t, err)
+		require.NoError(t, db.SaveBlock(context.Background(), wsb))
 		bRoots = append(bRoots, r)
 		prevRoot = r
 
@@ -594,7 +616,9 @@ func TestStore_CleanUpDirtyStates_Finalized(t *testing.T) {
 		b.Block.Slot = i
 		r, err := b.Block.HashTreeRoot()
 		require.NoError(t, err)
-		require.NoError(t, db.SaveBlock(context.Background(), wrapper.WrappedPhase0SignedBeaconBlock(b)))
+		wsb, err := wrapper.WrappedSignedBeaconBlock(b)
+		require.NoError(t, err)
+		require.NoError(t, db.SaveBlock(context.Background(), wsb))
 
 		st, err := util.NewBeaconState()
 		require.NoError(t, err)
@@ -622,7 +646,9 @@ func TestStore_CleanUpDirtyStates_DontDeleteNonFinalized(t *testing.T) {
 		b.Block.Slot = i
 		r, err := b.Block.HashTreeRoot()
 		require.NoError(t, err)
-		require.NoError(t, db.SaveBlock(context.Background(), wrapper.WrappedPhase0SignedBeaconBlock(b)))
+		wsb, err := wrapper.WrappedSignedBeaconBlock(b)
+		require.NoError(t, err)
+		require.NoError(t, db.SaveBlock(context.Background(), wsb))
 		unfinalizedRoots = append(unfinalizedRoots, r)
 
 		st, err := util.NewBeaconState()

beacon-chain/db/kv/validated_checkpoint.go

@@ -0,0 +1,49 @@
+package kv
+
+import (
+	"context"
+
+	"github.com/prysmaticlabs/prysm/encoding/bytesutil"
+	ethpb "github.com/prysmaticlabs/prysm/proto/prysm/v1alpha1"
+	bolt "go.etcd.io/bbolt"
+	"go.opencensus.io/trace"
+)
+
+// LastValidatedCheckpoint returns the latest fully validated checkpoint in beacon chain.
+func (s *Store) LastValidatedCheckpoint(ctx context.Context) (*ethpb.Checkpoint, error) {
+	ctx, span := trace.StartSpan(ctx, "BeaconDB.LastValidatedCheckpoint")
+	defer span.End()
+	var checkpoint *ethpb.Checkpoint
+	err := s.db.View(func(tx *bolt.Tx) error {
+		bkt := tx.Bucket(checkpointBucket)
+		enc := bkt.Get(lastValidatedCheckpointKey)
+		if enc == nil {
+			var finErr error
+			checkpoint, finErr = s.FinalizedCheckpoint(ctx)
+			return finErr
+		}
+		checkpoint = &ethpb.Checkpoint{}
+		return decode(ctx, enc, checkpoint)
+	})
+	return checkpoint, err
+}
+
+// SaveLastValidatedCheckpoint saves the last validated checkpoint in beacon chain.
+func (s *Store) SaveLastValidatedCheckpoint(ctx context.Context, checkpoint *ethpb.Checkpoint) error {
+	ctx, span := trace.StartSpan(ctx, "BeaconDB.SaveLastValidatedCheckpoint")
+	defer span.End()
+
+	enc, err := encode(ctx, checkpoint)
+	if err != nil {
+		return err
+	}
+	return s.db.Update(func(tx *bolt.Tx) error {
+		bucket := tx.Bucket(checkpointBucket)
+		hasStateSummary := s.hasStateSummaryBytes(tx, bytesutil.ToBytes32(checkpoint.Root))
+		hasStateInDB := tx.Bucket(stateBucket).Get(checkpoint.Root) != nil
+		if !(hasStateInDB || hasStateSummary) {
+			return errMissingStateForCheckpoint
+		}
+		return bucket.Put(lastValidatedCheckpointKey, enc)
+	})
+}