just remember this

op/sepolia/lisk/patch/optimism/op-node/rollup/derive/system_config.go

@@ -0,0 +1,152 @@
+package derive
+
+import (
+	"bytes"
+	"errors"
+	"fmt"
+
+	"github.com/hashicorp/go-multierror"
+
+	"github.com/ethereum/go-ethereum/common"
+	"github.com/ethereum/go-ethereum/core/types"
+	"github.com/ethereum/go-ethereum/crypto"
+
+	"github.com/ethereum-optimism/optimism/op-node/rollup"
+	"github.com/ethereum-optimism/optimism/op-service/eth"
+	"github.com/ethereum-optimism/optimism/op-service/solabi"
+)
+
+var (
+	SystemConfigUpdateBatcher           = common.Hash{31: 0}
+	SystemConfigUpdateGasConfig         = common.Hash{31: 1}
+	SystemConfigUpdateGasLimit          = common.Hash{31: 2}
+	SystemConfigUpdateUnsafeBlockSigner = common.Hash{31: 3}
+	SystemConfigUpdateGasConfigEcotone  = common.Hash{31: 4}
+)
+
+var (
+	ConfigUpdateEventABI      = "ConfigUpdate(uint256,uint8,bytes)"
+	ConfigUpdateEventABIHash  = crypto.Keccak256Hash([]byte(ConfigUpdateEventABI))
+	ConfigUpdateEventVersion0 = common.Hash{}
+)
+
+// UpdateSystemConfigWithL1Receipts filters all L1 receipts to find config updates and applies the config updates to the given sysCfg
+func UpdateSystemConfigWithL1Receipts(sysCfg *eth.SystemConfig, receipts []*types.Receipt, cfg *rollup.Config, l1Time uint64) error {
+	var result error
+	for i, rec := range receipts {
+		if rec.Status != types.ReceiptStatusSuccessful {
+			continue
+		}
+		for j, log := range rec.Logs {
+			if log.Address == cfg.L1SystemConfigAddress && len(log.Topics) > 0 && log.Topics[0] == ConfigUpdateEventABIHash {
+				if err := ProcessSystemConfigUpdateLogEvent(sysCfg, log, cfg, l1Time); err != nil {
+					result = multierror.Append(result, fmt.Errorf("malformatted L1 system sysCfg log in receipt %d, log %d: %w", i, j, err))
+				}
+			}
+		}
+	}
+	return result
+}
+
+// ProcessSystemConfigUpdateLogEvent decodes an EVM log entry emitted by the system config contract and applies it as a system config change.
+//
+// parse log data for:
+//
+//	event ConfigUpdate(
+//	    uint256 indexed version,
+//	    UpdateType indexed updateType,
+//	    bytes data
+//	);
+func ProcessSystemConfigUpdateLogEvent(destSysCfg *eth.SystemConfig, ev *types.Log, rollupCfg *rollup.Config, l1Time uint64) error {
+	if len(ev.Topics) != 3 {
+		return fmt.Errorf("expected 3 event topics (event identity, indexed version, indexed updateType), got %d", len(ev.Topics))
+	}
+	if ev.Topics[0] != ConfigUpdateEventABIHash {
+		return fmt.Errorf("invalid SystemConfig update event: %s, expected %s", ev.Topics[0], ConfigUpdateEventABIHash)
+	}
+
+	// indexed 0
+	version := ev.Topics[1]
+	if version != ConfigUpdateEventVersion0 {
+		return fmt.Errorf("unrecognized SystemConfig update event version: %s", version)
+	}
+	// indexed 1
+	updateType := ev.Topics[2]
+
+	// Create a reader of the unindexed data
+	reader := bytes.NewReader(ev.Data)
+
+	// Attempt to read unindexed data
+	switch updateType {
+	case SystemConfigUpdateBatcher:
+		if pointer, err := solabi.ReadUint64(reader); err != nil || pointer != 32 {
+			return NewCriticalError(errors.New("invalid pointer field"))
+		}
+		if length, err := solabi.ReadUint64(reader); err != nil || length != 32 {
+			return NewCriticalError(errors.New("invalid length field"))
+		}
+		address, err := solabi.ReadAddress(reader)
+		if err != nil {
+			return NewCriticalError(errors.New("could not read address"))
+		}
+		if !solabi.EmptyReader(reader) {
+			return NewCriticalError(errors.New("too many bytes"))
+		}
+		destSysCfg.BatcherAddr = address
+		return nil
+	case SystemConfigUpdateGasConfig:
+		if pointer, err := solabi.ReadUint64(reader); err != nil || pointer != 32 {
+			return NewCriticalError(errors.New("invalid pointer field"))
+		}
+		if length, err := solabi.ReadUint64(reader); err != nil || length != 64 {
+			return NewCriticalError(errors.New("invalid length field"))
+		}
+		overhead, err := solabi.ReadEthBytes32(reader)
+		if err != nil {
+			return NewCriticalError(errors.New("could not read overhead"))
+		}
+		scalar, err := solabi.ReadEthBytes32(reader)
+		if err != nil {
+			return NewCriticalError(errors.New("could not read scalar"))
+		}
+		if !solabi.EmptyReader(reader) {
+			return NewCriticalError(errors.New("too many bytes"))
+		}
+		if rollupCfg.IsEcotone(l1Time) {
+			if err := eth.CheckEcotoneL1SystemConfigScalar(scalar); err != nil {
+				return nil // ignore invalid scalars, retain the old system-config scalar
+			}
+			// retain the scalar data in encoded form
+			destSysCfg.Scalar = scalar
+			// zero out the overhead, it will not affect the state-transition after Ecotone
+			destSysCfg.Overhead = eth.Bytes32{}
+		} else {
+			destSysCfg.Overhead = overhead
+			destSysCfg.Scalar = scalar
+		}
+		return nil
+	case SystemConfigUpdateGasLimit:
+		if pointer, err := solabi.ReadUint64(reader); err != nil || pointer != 32 {
+			return NewCriticalError(errors.New("invalid pointer field"))
+		}
+		if length, err := solabi.ReadUint64(reader); err != nil || length != 32 {
+			return NewCriticalError(errors.New("invalid length field"))
+		}
+		gasLimit, err := solabi.ReadUint64(reader)
+		if err != nil {
+			return NewCriticalError(errors.New("could not read gas limit"))
+		}
+		if !solabi.EmptyReader(reader) {
+			return NewCriticalError(errors.New("too many bytes"))
+		}
+		destSysCfg.GasLimit = gasLimit
+		return nil
+	case SystemConfigUpdateUnsafeBlockSigner:
+		// Ignored in derivation. This configurable applies to runtime configuration outside of the derivation.
+		return nil
+	case SystemConfigUpdateGasConfigEcotone:
+	        return nil
+	default:
+		return fmt.Errorf("unrecognized L1 sysCfg update type: %s", updateType)
+	}
+}