Fix builder bid version compatibility to support Electra bids with Fulu blocks (#15536)

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

@@ -5,7 +5,6 @@ import (
 	"context"
 	"fmt"
 	"math/big"
-	"strings"
 	"time"
 
 	"github.com/OffchainLabs/prysm/v6/api/client/builder"
@@ -19,7 +18,6 @@ import (
 	"github.com/OffchainLabs/prysm/v6/encoding/ssz"
 	"github.com/OffchainLabs/prysm/v6/monitoring/tracing"
 	"github.com/OffchainLabs/prysm/v6/monitoring/tracing/trace"
-	"github.com/OffchainLabs/prysm/v6/network/forks"
 	enginev1 "github.com/OffchainLabs/prysm/v6/proto/engine/v1"
 	"github.com/OffchainLabs/prysm/v6/runtime/version"
 	"github.com/OffchainLabs/prysm/v6/time/slots"
@@ -220,16 +218,10 @@ func (vs *Server) getPayloadHeaderFromBuilder(
 	if signedBid == nil || signedBid.IsNil() {
 		return nil, errors.New("builder returned nil bid")
 	}
-	fork, err := forks.Fork(slots.ToEpoch(slot))
-	if err != nil {
-		return nil, errors.Wrap(err, "unable to get fork information")
-	}
-	forkName, ok := params.BeaconConfig().ForkVersionNames[bytesutil.ToBytes4(fork.CurrentVersion)]
-	if !ok {
-		return nil, errors.New("unable to find current fork in schedule")
-	}
-	if !strings.EqualFold(version.String(signedBid.Version()), forkName) {
-		return nil, fmt.Errorf("builder bid response version: %d is different from head block version: %d for epoch %d", signedBid.Version(), b.Version(), slots.ToEpoch(slot))
+	bidVersion := signedBid.Version()
+	headBlockVersion := b.Version()
+	if !isVersionCompatible(bidVersion, headBlockVersion) {
+		return nil, fmt.Errorf("builder bid response version: %d is not compatible with head block version: %d for epoch %d", bidVersion, headBlockVersion, slots.ToEpoch(slot))
 	}
 
 	bid, err := signedBid.Message()
@@ -466,3 +458,19 @@ func expectedGasLimit(parentGasLimit, proposerGasLimit uint64) uint64 {
 	}
 	return proposerGasLimit
 }
+
+// isVersionCompatible checks if a builder bid version is compatible with the head block version.
+func isVersionCompatible(bidVersion, headBlockVersion int) bool {
+	// Exact version match is always compatible
+	if bidVersion == headBlockVersion {
+		return true
+	}
+
+	// Allow Electra bids for Fulu blocks - they have compatible payload formats
+	if bidVersion == version.Electra && headBlockVersion == version.Fulu {
+		return true
+	}
+
+	// For all other cases, require exact version match
+	return false
+}

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

@@ -25,6 +25,7 @@ import (
 	"github.com/OffchainLabs/prysm/v6/encoding/ssz"
 	v1 "github.com/OffchainLabs/prysm/v6/proto/engine/v1"
 	ethpb "github.com/OffchainLabs/prysm/v6/proto/prysm/v1alpha1"
+	"github.com/OffchainLabs/prysm/v6/runtime/version"
 	"github.com/OffchainLabs/prysm/v6/testing/require"
 	"github.com/OffchainLabs/prysm/v6/testing/util"
 	"github.com/OffchainLabs/prysm/v6/time/slots"
@@ -156,7 +157,7 @@ func TestServer_setExecutionData(t *testing.T) {
 			HasConfigured: true,
 			Cfg:           &builderTest.Config{BeaconDB: beaconDB},
 		}
-		wb, err := blocks.NewSignedBeaconBlock(util.NewBeaconBlockBellatrix())
+		wb, err := blocks.NewSignedBeaconBlock(util.NewBeaconBlockCapella())
 		require.NoError(t, err)
 		chain := &blockchainTest.ChainService{ForkChoiceStore: doublylinkedtree.New(), Genesis: time.Now(), Block: wb}
 		vs.ForkchoiceFetcher = chain
@@ -973,7 +974,7 @@ func TestServer_getPayloadHeader(t *testing.T) {
 					return wb
 				}(),
 			},
-			err: "is different from head block version",
+			err: "builder bid response version: 3 is not compatible with head block version: 2 for epoch 1",
 		},
 		{
 			name: "different bid version during hard fork",
@@ -982,7 +983,7 @@ func TestServer_getPayloadHeader(t *testing.T) {
 			},
 			fetcher: &blockchainTest.ChainService{
 				Block: func() interfaces.ReadOnlySignedBeaconBlock {
-					wb, err := blocks.NewSignedBeaconBlock(util.NewBeaconBlockBellatrix())
+					wb, err := blocks.NewSignedBeaconBlock(util.NewBeaconBlockCapella())
 					require.NoError(t, err)
 					wb.SetSlot(primitives.Slot(fakeCapellaEpoch) * params.BeaconConfig().SlotsPerEpoch)
 					return wb
@@ -1005,6 +1006,86 @@ func TestServer_getPayloadHeader(t *testing.T) {
 			},
 			err: "incorrect header gas limit 30000000 != 31000000",
 		},
+		{
+			name: "electra bid with fulu head block - compatible",
+			mock: func() *builderTest.MockBuilderService {
+				// Create Electra bid
+				requests := &v1.ExecutionRequests{
+					Deposits: []*v1.DepositRequest{
+						{
+							Pubkey:                bytesutil.PadTo([]byte{byte('a')}, fieldparams.BLSPubkeyLength),
+							WithdrawalCredentials: bytesutil.PadTo([]byte{byte('b')}, fieldparams.RootLength),
+							Amount:                params.BeaconConfig().MinActivationBalance,
+							Signature:             bytesutil.PadTo([]byte{byte('c')}, fieldparams.BLSSignatureLength),
+							Index:                 0,
+						},
+					},
+					Withdrawals: []*v1.WithdrawalRequest{
+						{
+							SourceAddress:   bytesutil.PadTo([]byte{byte('d')}, common.AddressLength),
+							ValidatorPubkey: bytesutil.PadTo([]byte{byte('e')}, fieldparams.BLSPubkeyLength),
+							Amount:          params.BeaconConfig().MinActivationBalance,
+						},
+					},
+					Consolidations: []*v1.ConsolidationRequest{
+						{
+							SourceAddress: bytesutil.PadTo([]byte{byte('f')}, common.AddressLength),
+							SourcePubkey:  bytesutil.PadTo([]byte{byte('g')}, fieldparams.BLSPubkeyLength),
+							TargetPubkey:  bytesutil.PadTo([]byte{byte('h')}, fieldparams.BLSPubkeyLength),
+						},
+					},
+				}
+
+				electraBid := &ethpb.BuilderBidElectra{
+					Header: &v1.ExecutionPayloadHeaderDeneb{
+						FeeRecipient:     make([]byte, fieldparams.FeeRecipientLength),
+						StateRoot:        make([]byte, fieldparams.RootLength),
+						ReceiptsRoot:     make([]byte, fieldparams.RootLength),
+						LogsBloom:        make([]byte, fieldparams.LogsBloomLength),
+						PrevRandao:       make([]byte, fieldparams.RootLength),
+						BaseFeePerGas:    make([]byte, fieldparams.RootLength),
+						BlockHash:        make([]byte, fieldparams.RootLength),
+						TransactionsRoot: bytesutil.PadTo([]byte{1}, fieldparams.RootLength),
+						ParentHash:       params.BeaconConfig().ZeroHash[:],
+						Timestamp:        uint64(ti.Unix()),
+						BlockNumber:      2,
+						WithdrawalsRoot:  make([]byte, fieldparams.RootLength),
+						BlobGasUsed:      123,
+						ExcessBlobGas:    456,
+						GasLimit:         gasLimit,
+					},
+					Pubkey:             sk.PublicKey().Marshal(),
+					Value:              bytesutil.PadTo([]byte{1, 2, 3}, 32),
+					BlobKzgCommitments: [][]byte{bytesutil.PadTo([]byte{2}, fieldparams.BLSPubkeyLength)},
+					ExecutionRequests:  requests,
+				}
+
+				d := params.BeaconConfig().DomainApplicationBuilder
+				domain, err := signing.ComputeDomain(d, nil, nil)
+				require.NoError(t, err)
+				sr, err := signing.ComputeSigningRoot(electraBid, domain)
+				require.NoError(t, err)
+
+				sBidElectra := &ethpb.SignedBuilderBidElectra{
+					Message:   electraBid,
+					Signature: sk.Sign(sr[:]).Marshal(),
+				}
+
+				return &builderTest.MockBuilderService{
+					BidElectra: sBidElectra,
+				}
+			}(),
+			fetcher: &blockchainTest.ChainService{
+				Block: func() interfaces.ReadOnlySignedBeaconBlock {
+					// Create Fulu head block
+					wb, err := blocks.NewSignedBeaconBlock(util.NewBeaconBlockFulu())
+					require.NoError(t, err)
+					wb.SetSlot(primitives.Slot(params.BeaconConfig().BellatrixForkEpoch) * params.BeaconConfig().SlotsPerEpoch)
+					return wb
+				}(),
+			},
+			// Should succeed because Electra bids are compatible with Fulu head blocks
+		},
 	}
 	for _, tc := range tests {
 		t.Run(tc.name, func(t *testing.T) {
@@ -1222,3 +1303,107 @@ func Test_expectedGasLimit(t *testing.T) {
 		})
 	}
 }
+
+func TestIsVersionCompatible(t *testing.T) {
+
+	tests := []struct {
+		name             string
+		bidVersion       int
+		headBlockVersion int
+		want             bool
+	}{
+		{
+			name:             "Exact version match - Bellatrix",
+			bidVersion:       version.Bellatrix,
+			headBlockVersion: version.Bellatrix,
+			want:             true,
+		},
+		{
+			name:             "Exact version match - Capella",
+			bidVersion:       version.Capella,
+			headBlockVersion: version.Capella,
+			want:             true,
+		},
+		{
+			name:             "Exact version match - Deneb",
+			bidVersion:       version.Deneb,
+			headBlockVersion: version.Deneb,
+			want:             true,
+		},
+		{
+			name:             "Exact version match - Electra",
+			bidVersion:       version.Electra,
+			headBlockVersion: version.Electra,
+			want:             true,
+		},
+		{
+			name:             "Exact version match - Fulu",
+			bidVersion:       version.Fulu,
+			headBlockVersion: version.Fulu,
+			want:             true,
+		},
+		{
+			name:             "Electra bid with Fulu head block - Compatible",
+			bidVersion:       version.Electra,
+			headBlockVersion: version.Fulu,
+			want:             true,
+		},
+		{
+			name:             "Fulu bid with Electra head block - Not compatible",
+			bidVersion:       version.Fulu,
+			headBlockVersion: version.Electra,
+			want:             false,
+		},
+		{
+			name:             "Deneb bid with Electra head block - Not compatible",
+			bidVersion:       version.Deneb,
+			headBlockVersion: version.Electra,
+			want:             false,
+		},
+		{
+			name:             "Electra bid with Deneb head block - Not compatible",
+			bidVersion:       version.Electra,
+			headBlockVersion: version.Deneb,
+			want:             false,
+		},
+		{
+			name:             "Capella bid with Deneb head block - Not compatible",
+			bidVersion:       version.Capella,
+			headBlockVersion: version.Deneb,
+			want:             false,
+		},
+		{
+			name:             "Bellatrix bid with Capella head block - Not compatible",
+			bidVersion:       version.Bellatrix,
+			headBlockVersion: version.Capella,
+			want:             false,
+		},
+		{
+			name:             "Phase0 bid with Altair head block - Not compatible",
+			bidVersion:       version.Phase0,
+			headBlockVersion: version.Altair,
+			want:             false,
+		},
+		{
+			name:             "Deneb bid with Fulu head block - Not compatible",
+			bidVersion:       version.Deneb,
+			headBlockVersion: version.Fulu,
+			want:             false,
+		},
+		{
+			name:             "Capella bid with Fulu head block - Not compatible",
+			bidVersion:       version.Capella,
+			headBlockVersion: version.Fulu,
+			want:             false,
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			got := isVersionCompatible(tt.bidVersion, tt.headBlockVersion)
+			if got != tt.want {
+				t.Errorf("isVersionCompatible(%d, %d) = %v, want %v", tt.bidVersion, tt.headBlockVersion, got, tt.want)
+			}
+		})
+	}
+}

changelog/fix-fulu-bid-compatibility.md

@@ -0,0 +1,3 @@
+### Fixed
+
+- Fix builder bid version compatibility to support Electra bids with Fulu blocks