Add withdrawals attribute / port geth v2 checks

op-program/client/l2/engineapi/l2_engine_api.go

@@ -6,6 +6,7 @@ import (
 	"encoding/binary"
 	"errors"
 	"fmt"
+	"math/big"
 	"time"
 
 	"github.com/ethereum-optimism/optimism/op-service/eth"
@@ -185,19 +186,70 @@ func (ea *L2EngineAPI) GetPayloadV2(ctx context.Context, payloadId eth.PayloadID
 	return &eth.ExecutionPayloadEnvelope{ExecutionPayload: payload}, err
 }
 
+func (ea *L2EngineAPI) config() *params.ChainConfig {
+	return ea.backend.Config()
+}
+
 func (ea *L2EngineAPI) ForkchoiceUpdatedV1(ctx context.Context, state *eth.ForkchoiceState, attr *eth.PayloadAttributes) (*eth.ForkchoiceUpdatedResult, error) {
+	if attr != nil {
+		if attr.Withdrawals != nil {
+			return STATUS_INVALID, engine.InvalidParams.With(errors.New("withdrawals not supported in V1"))
+		}
+		if ea.config().IsShanghai(ea.config().LondonBlock, uint64(attr.Timestamp)) {
+			return STATUS_INVALID, engine.InvalidParams.With(errors.New("forkChoiceUpdateV1 called post-shanghai"))
+		}
+	}
+
 	return ea.forkchoiceUpdated(ctx, state, attr)
 }
 
 func (ea *L2EngineAPI) ForkchoiceUpdatedV2(ctx context.Context, state *eth.ForkchoiceState, attr *eth.PayloadAttributes) (*eth.ForkchoiceUpdatedResult, error) {
+	if attr != nil {
+		if err := ea.verifyPayloadAttributes(attr); err != nil {
+			return STATUS_INVALID, engine.InvalidParams.With(err)
+		}
+	}
+
 	return ea.forkchoiceUpdated(ctx, state, attr)
 }
 
+func (ea *L2EngineAPI) verifyPayloadAttributes(attr *eth.PayloadAttributes) error {
+	c := ea.config()
+
+	// Verify withdrawals attribute for Shanghai.
+	if err := checkAttribute(c.IsShanghai, attr.Withdrawals != nil, c.LondonBlock, uint64(attr.Timestamp)); err != nil {
+		return fmt.Errorf("invalid withdrawals: %w", err)
+	}
+	return nil
+}
+
+func checkAttribute(active func(*big.Int, uint64) bool, exists bool, block *big.Int, time uint64) error {
+	if active(block, time) && !exists {
+		return errors.New("fork active, missing expected attribute")
+	}
+	if !active(block, time) && exists {
+		return errors.New("fork inactive, unexpected attribute set")
+	}
+	return nil
+}
+
 func (ea *L2EngineAPI) NewPayloadV1(ctx context.Context, payload *eth.ExecutionPayload) (*eth.PayloadStatusV1, error) {
+	if payload.Withdrawals != nil {
+		return &eth.PayloadStatusV1{Status: eth.ExecutionInvalid}, engine.InvalidParams.With(errors.New("withdrawals not supported in V1"))
+	}
+
 	return ea.newPayload(ctx, payload)
 }
 
 func (ea *L2EngineAPI) NewPayloadV2(ctx context.Context, payload *eth.ExecutionPayload) (*eth.PayloadStatusV1, error) {
+	if ea.config().IsShanghai(new(big.Int).SetUint64(uint64(payload.BlockNumber)), uint64(payload.Timestamp)) {
+		if payload.Withdrawals == nil {
+			return &eth.PayloadStatusV1{Status: eth.ExecutionInvalid}, engine.InvalidParams.With(errors.New("nil withdrawals post-shanghai"))
+		}
+	} else if payload.Withdrawals != nil {
+		return &eth.PayloadStatusV1{Status: eth.ExecutionInvalid}, engine.InvalidParams.With(errors.New("non-nil withdrawals pre-shanghai"))
+	}
+
 	return ea.newPayload(ctx, payload)
 }
 

op-service/eth/types.go

@@ -143,6 +143,7 @@ type ExecutionPayload struct {
 	ExtraData     BytesMax32      `json:"extraData"`
 	BaseFeePerGas Uint256Quantity `json:"baseFeePerGas"`
 	BlockHash     common.Hash     `json:"blockHash"`
+	Withdrawals   *[]Withdrawal   `json:"withdrawals,omitempty"`
 	// Array of transaction objects, each object is a byte list (DATA) representing
 	// TransactionType || TransactionPayload or LegacyTransaction as defined in EIP-2718
 	Transactions []Data `json:"transactions"`
@@ -232,6 +233,8 @@ type PayloadAttributes struct {
 	PrevRandao Bytes32 `json:"prevRandao"`
 	// suggested value for the coinbase field of the new payload
 	SuggestedFeeRecipient common.Address `json:"suggestedFeeRecipient"`
+	// Withdrawals to include into the block -- should be nil or empty depending on Shanghai enablement
+	Withdrawals *[]Withdrawal `json:"withdrawals,omitempty"`
 	// Transactions to force into the block (always at the start of the transactions list).
 	Transactions []Data `json:"transactions,omitempty"`
 	// NoTxPool to disable adding any transactions from the transaction-pool.
@@ -297,3 +300,11 @@ type SystemConfig struct {
 	GasLimit uint64 `json:"gasLimit"`
 	// More fields can be added for future SystemConfig versions.
 }
+
+// Withdrawal represents a validator withdrawal from the consensus layer.
+type Withdrawal struct {
+	Index     uint64         `json:"index"`          // monotonically increasing identifier issued by consensus layer
+	Validator uint64         `json:"validatorIndex"` // index of validator associated with withdrawal
+	Address   common.Address `json:"address"`        // target address for withdrawn ether
+	Amount    uint64         `json:"amount"`         // value of withdrawal in Gwei
+}