beacon, core, eth, miner: integrate witnesses into production Geth

beacon/engine/gen_epe.go

@@ -19,12 +19,14 @@ func (e ExecutionPayloadEnvelope) MarshalJSON() ([]byte, error) {
 		BlockValue       *hexutil.Big    `json:"blockValue"  gencodec:"required"`
 		BlobsBundle      *BlobsBundleV1  `json:"blobsBundle"`
 		Override         bool            `json:"shouldOverrideBuilder"`
+		Witness          *hexutil.Bytes  `json:"witness"`
 	}
 	var enc ExecutionPayloadEnvelope
 	enc.ExecutionPayload = e.ExecutionPayload
 	enc.BlockValue = (*hexutil.Big)(e.BlockValue)
 	enc.BlobsBundle = e.BlobsBundle
 	enc.Override = e.Override
+	enc.Witness = e.Witness
 	return json.Marshal(&enc)
 }
 
@@ -35,6 +37,7 @@ func (e *ExecutionPayloadEnvelope) UnmarshalJSON(input []byte) error {
 		BlockValue       *hexutil.Big    `json:"blockValue"  gencodec:"required"`
 		BlobsBundle      *BlobsBundleV1  `json:"blobsBundle"`
 		Override         *bool           `json:"shouldOverrideBuilder"`
+		Witness          *hexutil.Bytes  `json:"witness"`
 	}
 	var dec ExecutionPayloadEnvelope
 	if err := json.Unmarshal(input, &dec); err != nil {
@@ -54,5 +57,8 @@ func (e *ExecutionPayloadEnvelope) UnmarshalJSON(input []byte) error {
 	if dec.Override != nil {
 		e.Override = *dec.Override
 	}
+	if dec.Witness != nil {
+		e.Witness = dec.Witness
+	}
 	return nil
 }

beacon/engine/types.go

@@ -94,6 +94,14 @@ type executableDataMarshaling struct {
 	ExcessBlobGas *hexutil.Uint64
 }
 
+// StatelessPayloadStatusV1 is the result of a stateless payload execution.
+type StatelessPayloadStatusV1 struct {
+	Status          string      `json:"status"`
+	StateRoot       common.Hash `json:"stateRoot"`
+	ReceiptsRoot    common.Hash `json:"receiptsRoot"`
+	ValidationError *string     `json:"validationError"`
+}
+
 //go:generate go run github.com/fjl/gencodec -type ExecutionPayloadEnvelope -field-override executionPayloadEnvelopeMarshaling -out gen_epe.go
 
 type ExecutionPayloadEnvelope struct {
@@ -101,6 +109,7 @@ type ExecutionPayloadEnvelope struct {
 	BlockValue       *big.Int        `json:"blockValue"  gencodec:"required"`
 	BlobsBundle      *BlobsBundleV1  `json:"blobsBundle"`
 	Override         bool            `json:"shouldOverrideBuilder"`
+	Witness          *hexutil.Bytes  `json:"witness"`
 }
 
 type BlobsBundleV1 struct {
@@ -116,6 +125,7 @@ type executionPayloadEnvelopeMarshaling struct {
 
 type PayloadStatusV1 struct {
 	Status          string         `json:"status"`
+	Witness         *hexutil.Bytes `json:"witness"`
 	LatestValidHash *common.Hash   `json:"latestValidHash"`
 	ValidationError *string        `json:"validationError"`
 }
@@ -198,6 +208,20 @@ func decodeTransactions(enc [][]byte) ([]*types.Transaction, error) {
 // Withdrawals value will propagate through the returned block. Empty
 // Withdrawals value must be passed via non-nil, length 0 value in data.
 func ExecutableDataToBlock(data ExecutableData, versionedHashes []common.Hash, beaconRoot *common.Hash) (*types.Block, error) {
+	block, err := ExecutableDataToBlockNoHash(data, versionedHashes, beaconRoot)
+	if err != nil {
+		return nil, err
+	}
+	if block.Hash() != data.BlockHash {
+		return nil, fmt.Errorf("blockhash mismatch, want %x, got %x", data.BlockHash, block.Hash())
+	}
+	return block, nil
+}
+
+// ExecutableDataToBlockNoHash is analogous to ExecutableDataToBlock, but is used
+// for stateless execution, so it skips checking if the executable data hashes to
+// the requested hash (stateless has to *compute* the root hash, it's not given).
+func ExecutableDataToBlockNoHash(data ExecutableData, versionedHashes []common.Hash, beaconRoot *common.Hash) (*types.Block, error) {
 	txs, err := decodeTransactions(data.Transactions)
 	if err != nil {
 		return nil, err
@@ -267,13 +291,10 @@ func ExecutableDataToBlock(data ExecutableData, versionedHashes []common.Hash, b
 		ParentBeaconRoot: beaconRoot,
 		RequestsHash:     requestsHash,
 	}
-	block := types.NewBlockWithHeader(header)
-	block = block.WithBody(types.Body{Transactions: txs, Uncles: nil, Withdrawals: data.Withdrawals, Requests: requests})
-	block = block.WithWitness(data.ExecutionWitness)
-	if block.Hash() != data.BlockHash {
-		return nil, fmt.Errorf("blockhash mismatch, want %x, got %x", data.BlockHash, block.Hash())
-	}
-	return block, nil
+	return types.NewBlockWithHeader(header).
+			WithBody(types.Body{Transactions: txs, Uncles: nil, Withdrawals: data.Withdrawals, Requests: requests}).
+			WithWitness(data.ExecutionWitness),
+		nil
 }
 
 // BlockToExecutableData constructs the ExecutableData structure by filling the

cmd/geth/main.go

@@ -156,7 +156,6 @@ var (
 		utils.BeaconGenesisRootFlag,
 		utils.BeaconGenesisTimeFlag,
 		utils.BeaconCheckpointFlag,
-		utils.CollectWitnessFlag,
 	}, utils.NetworkFlags, utils.DatabaseFlags)
 
 	rpcFlags = []cli.Flag{

cmd/utils/flags.go

@@ -600,11 +600,6 @@ var (
 		Usage:    "Disables db compaction after import",
 		Category: flags.LoggingCategory,
 	}
-	CollectWitnessFlag = &cli.BoolFlag{
-		Name:     "collectwitness",
-		Usage:    "Enable state witness generation during block execution. Work in progress flag, don't use.",
-		Category: flags.MiscCategory,
-	}
 
 	// MISC settings
 	SyncTargetFlag = &cli.StringFlag{
@@ -1767,9 +1762,6 @@ func SetEthConfig(ctx *cli.Context, stack *node.Node, cfg *ethconfig.Config) {
 		// TODO(fjl): force-enable this in --dev mode
 		cfg.EnablePreimageRecording = ctx.Bool(VMEnableDebugFlag.Name)
 	}
-	if ctx.IsSet(CollectWitnessFlag.Name) {
-		cfg.EnableWitnessCollection = ctx.Bool(CollectWitnessFlag.Name)
-	}
 
 	if ctx.IsSet(RPCGlobalGasCapFlag.Name) {
 		cfg.RPCGasCap = ctx.Uint64(RPCGlobalGasCapFlag.Name)
@@ -2194,7 +2186,6 @@ func MakeChain(ctx *cli.Context, stack *node.Node, readonly bool) (*core.BlockCh
 	}
 	vmcfg := vm.Config{
 		EnablePreimageRecording: ctx.Bool(VMEnableDebugFlag.Name),
-		EnableWitnessCollection: ctx.Bool(CollectWitnessFlag.Name),
 	}
 	if ctx.IsSet(VMTraceFlag.Name) {
 		if name := ctx.String(VMTraceFlag.Name); name != "" {

core/block_validator.go

@@ -20,10 +20,8 @@ import (
 	"errors"
 	"fmt"
 
-	"github.com/ethereum/go-ethereum/common"
 	"github.com/ethereum/go-ethereum/consensus"
 	"github.com/ethereum/go-ethereum/core/state"
-	"github.com/ethereum/go-ethereum/core/stateless"
 	"github.com/ethereum/go-ethereum/core/types"
 	"github.com/ethereum/go-ethereum/params"
 	"github.com/ethereum/go-ethereum/trie"
@@ -160,28 +158,6 @@ func (v *BlockValidator) ValidateState(block *types.Block, statedb *state.StateD
 	return nil
 }
 
-// ValidateWitness cross validates a block execution with stateless remote clients.
-//
-// Normally we'd distribute the block witness to remote cross validators, wait
-// for them to respond and then merge the results. For now, however, it's only
-// Geth, so do an internal stateless run.
-func (v *BlockValidator) ValidateWitness(witness *stateless.Witness, receiptRoot common.Hash, stateRoot common.Hash) error {
-	// Run the cross client stateless execution
-	// TODO(karalabe): Self-stateless for now, swap with other clients
-	crossReceiptRoot, crossStateRoot, err := ExecuteStateless(v.config, witness)
-	if err != nil {
-		return fmt.Errorf("stateless execution failed: %v", err)
-	}
-	// Stateless cross execution suceeeded, validate the withheld computed fields
-	if crossReceiptRoot != receiptRoot {
-		return fmt.Errorf("cross validator receipt root mismatch (cross: %x local: %x)", crossReceiptRoot, receiptRoot)
-	}
-	if crossStateRoot != stateRoot {
-		return fmt.Errorf("cross validator state root mismatch (cross: %x local: %x)", crossStateRoot, stateRoot)
-	}
-	return nil
-}
-
 // CalcGasLimit computes the gas limit of the next block after parent. It aims
 // to keep the baseline gas close to the provided target, and increase it towards
 // the target if the baseline gas is lower.

core/block_validator_test.go

@@ -201,7 +201,7 @@ func testHeaderVerificationForMerging(t *testing.T, isClique bool) {
 			t.Fatalf("post-block %d: unexpected result returned: %v", i, result)
 		case <-time.After(25 * time.Millisecond):
 		}
-		chain.InsertBlockWithoutSetHead(postBlocks[i])
+		chain.InsertBlockWithoutSetHead(postBlocks[i], false)
 	}
 
 	// Verify the blocks with pre-merge blocks and post-merge blocks

core/blockchain.go

@@ -80,6 +80,7 @@ var (
 
 	blockInsertTimer          = metrics.NewRegisteredResettingTimer("chain/inserts", nil)
 	blockValidationTimer      = metrics.NewRegisteredResettingTimer("chain/validation", nil)
+	blockCrossValidationTimer = metrics.NewRegisteredResettingTimer("chain/crossvalidation", nil)
 	blockExecutionTimer       = metrics.NewRegisteredResettingTimer("chain/execution", nil)
 	blockWriteTimer           = metrics.NewRegisteredResettingTimer("chain/write", nil)
 
@@ -1598,7 +1599,9 @@ func (bc *BlockChain) InsertChain(chain types.Blocks) (int, error) {
 		return 0, errChainStopped
 	}
 	defer bc.chainmu.Unlock()
-	return bc.insertChain(chain, true)
+
+	_, n, err := bc.insertChain(chain, true, false) // No witness collection for mass inserts (would get super large)
+	return n, err
 }
 
 // insertChain is the internal implementation of InsertChain, which assumes that
@@ -1609,10 +1612,10 @@ func (bc *BlockChain) InsertChain(chain types.Blocks) (int, error) {
 // racey behaviour. If a sidechain import is in progress, and the historic state
 // is imported, but then new canon-head is added before the actual sidechain
 // completes, then the historic state could be pruned again
-func (bc *BlockChain) insertChain(chain types.Blocks, setHead bool) (int, error) {
+func (bc *BlockChain) insertChain(chain types.Blocks, setHead bool, makeWitness bool) (*stateless.Witness, int, error) {
 	// If the chain is terminating, don't even bother starting up.
 	if bc.insertStopped() {
-		return 0, nil
+		return nil, 0, nil
 	}
 	// Start a parallel signature recovery (signer will fluke on fork transition, minimal perf loss)
 	SenderCacher.RecoverFromBlocks(types.MakeSigner(bc.chainConfig, chain[0].Number(), chain[0].Time()), chain)
@@ -1667,7 +1670,7 @@ func (bc *BlockChain) insertChain(chain types.Blocks, setHead bool) (int, error)
 		for block != nil && bc.skipBlock(err, it) {
 			log.Debug("Writing previously known block", "number", block.Number(), "hash", block.Hash())
 			if err := bc.writeKnownBlock(block); err != nil {
-				return it.index, err
+				return nil, it.index, err
 			}
 			lastCanon = block
 
@@ -1681,12 +1684,12 @@ func (bc *BlockChain) insertChain(chain types.Blocks, setHead bool) (int, error)
 		if setHead {
 			// First block is pruned, insert as sidechain and reorg only if TD grows enough
 			log.Debug("Pruned ancestor, inserting as sidechain", "number", block.Number(), "hash", block.Hash())
-			return bc.insertSideChain(block, it)
+			return bc.insertSideChain(block, it, makeWitness)
 		} else {
 			// We're post-merge and the parent is pruned, try to recover the parent state
 			log.Debug("Pruned ancestor", "number", block.Number(), "hash", block.Hash())
 			_, err := bc.recoverAncestors(block)
-			return it.index, err
+			return nil, it.index, err
 		}
 	// Some other error(except ErrKnownBlock) occurred, abort.
 	// ErrKnownBlock is allowed here since some known blocks
@@ -1694,7 +1697,7 @@ func (bc *BlockChain) insertChain(chain types.Blocks, setHead bool) (int, error)
 	case err != nil && !errors.Is(err, ErrKnownBlock):
 		stats.ignored += len(it.chain)
 		bc.reportBlock(block, nil, err)
-		return it.index, err
+		return nil, it.index, err
 	}
 	// No validation errors for the first block (or chain prefix skipped)
 	var activeState *state.StateDB
@@ -1708,6 +1711,9 @@ func (bc *BlockChain) insertChain(chain types.Blocks, setHead bool) (int, error)
 		}
 	}()
 
+	// Track the singleton witness from this chain insertion (if any)
+	var witness *stateless.Witness
+
 	for ; block != nil && err == nil || errors.Is(err, ErrKnownBlock); block, err = it.next() {
 		// If the chain is terminating, stop processing blocks
 		if bc.insertStopped() {
@@ -1744,7 +1750,7 @@ func (bc *BlockChain) insertChain(chain types.Blocks, setHead bool) (int, error)
 					"hash", block.Hash(), "number", block.NumberU64())
 			}
 			if err := bc.writeKnownBlock(block); err != nil {
-				return it.index, err
+				return nil, it.index, err
 			}
 			stats.processed++
 			if bc.logger != nil && bc.logger.OnSkippedBlock != nil {
@@ -1755,13 +1761,11 @@ func (bc *BlockChain) insertChain(chain types.Blocks, setHead bool) (int, error)
 					Safe:      bc.CurrentSafeBlock(),
 				})
 			}
-
 			// We can assume that logs are empty here, since the only way for consecutive
 			// Clique blocks to have the same state is if there are no transactions.
 			lastCanon = block
 			continue
 		}
-
 		// Retrieve the parent block and it's state to execute on top
 		start := time.Now()
 		parent := it.previous()
@@ -1770,7 +1774,7 @@ func (bc *BlockChain) insertChain(chain types.Blocks, setHead bool) (int, error)
 		}
 		statedb, err := state.New(parent.Root, bc.statedb)
 		if err != nil {
-			return it.index, err
+			return nil, it.index, err
 		}
 		statedb.SetLogger(bc.logger)
 
@@ -1778,11 +1782,13 @@ func (bc *BlockChain) insertChain(chain types.Blocks, setHead bool) (int, error)
 		// while processing transactions. Before Byzantium the prefetcher is mostly
 		// useless due to the intermediate root hashing after each transaction.
 		if bc.chainConfig.IsByzantium(block.Number()) {
-			var witness *stateless.Witness
-			if bc.vmConfig.EnableWitnessCollection {
-				witness, err = stateless.NewWitness(bc, block)
+			// Generate witnesses either if we're self-testing, or if it's the
+			// only block being inserted. A bit crude, but witnesses are huge,
+			// so we refuse to make an entire chain of them.
+			if bc.vmConfig.StatelessSelfValidation || (makeWitness && len(chain) == 1) {
+				witness, err = stateless.NewWitness(block.Header(), bc)
 				if err != nil {
-					return it.index, err
+					return nil, it.index, err
 				}
 			}
 			statedb.StartPrefetcher("chain", witness)
@@ -1814,7 +1820,7 @@ func (bc *BlockChain) insertChain(chain types.Blocks, setHead bool) (int, error)
 		res, err := bc.processBlock(block, statedb, start, setHead)
 		followupInterrupt.Store(true)
 		if err != nil {
-			return it.index, err
+			return nil, it.index, err
 		}
 		// Report the import stats before returning the various results
 		stats.processed++
@@ -1831,7 +1837,7 @@ func (bc *BlockChain) insertChain(chain types.Blocks, setHead bool) (int, error)
 			// After merge we expect few side chains. Simply count
 			// all blocks the CL gives us for GC processing time
 			bc.gcproc += res.procTime
-			return it.index, nil // Direct block insertion of a single block
+			return witness, it.index, nil // Direct block insertion of a single block
 		}
 		switch res.status {
 		case CanonStatTy:
@@ -1861,7 +1867,7 @@ func (bc *BlockChain) insertChain(chain types.Blocks, setHead bool) (int, error)
 		}
 	}
 	stats.ignored += it.remaining()
-	return it.index, err
+	return witness, it.index, err
 }
 
 // blockProcessingResult is a summary of block processing
@@ -1906,13 +1912,36 @@ func (bc *BlockChain) processBlock(block *types.Block, statedb *state.StateDB, s
 	}
 	vtime := time.Since(vstart)
 
-	if witness := statedb.Witness(); witness != nil {
-		if err = bc.validator.ValidateWitness(witness, block.ReceiptHash(), block.Root()); err != nil {
-			bc.reportBlock(block, res, err)
-			return nil, fmt.Errorf("cross verification failed: %v", err)
+	// If witnesses was generated and stateless self-validation requested, do
+	// that now. Self validation should *never* run in production, it's more of
+	// a tight integration to enable running *all* consensus tests through the
+	// witness builder/runner, which would otherwise be impossible due to the
+	// various invalid chain states/behaviors being contained in those tests.
+	xvstart := time.Now()
+	if witness := statedb.Witness(); witness != nil && bc.vmConfig.StatelessSelfValidation {
+		log.Warn("Running stateless self-validation", "block", block.Number(), "hash", block.Hash())
+
+		// Remove critical computed fields from the block to force true recalculation
+		context := block.Header()
+		context.Root = common.Hash{}
+		context.ReceiptHash = common.Hash{}
+
+		task := types.NewBlockWithHeader(context).WithBody(*block.Body())
+
+		// Run the stateless self-cross-validation
+		crossStateRoot, crossReceiptRoot, err := ExecuteStateless(bc.chainConfig, task, witness)
+		if err != nil {
+			return nil, fmt.Errorf("stateless self-validation failed: %v", err)
+		}
+		if crossStateRoot != block.Root() {
+			return nil, fmt.Errorf("stateless self-validation root mismatch (cross: %x local: %x)", crossStateRoot, block.Root())
 		}
+		if crossReceiptRoot != block.ReceiptHash() {
+			return nil, fmt.Errorf("stateless self-validation receipt root mismatch (cross: %x local: %x)", crossReceiptRoot, block.ReceiptHash())
 		}
-	proctime := time.Since(start) // processing + validation
+	}
+	xvtime := time.Since(xvstart)
+	proctime := time.Since(start) // processing + validation + cross validation
 
 	// Update the metrics touched during block processing and validation
 	accountReadTimer.Update(statedb.AccountReads) // Account reads are complete(in processing)
@@ -1930,6 +1959,7 @@ func (bc *BlockChain) processBlock(block *types.Block, statedb *state.StateDB, s
 	trieUpdate := statedb.AccountUpdates + statedb.StorageUpdates                     // The time spent on tries update
 	blockExecutionTimer.Update(ptime - (statedb.AccountReads + statedb.StorageReads)) // The time spent on EVM processing
 	blockValidationTimer.Update(vtime - (triehash + trieUpdate))                      // The time spent on block validation
+	blockCrossValidationTimer.Update(xvtime)                                          // The time spent on stateless cross validation
 
 	// Write the block to the chain and get the status.
 	var (
@@ -1964,7 +1994,7 @@ func (bc *BlockChain) processBlock(block *types.Block, statedb *state.StateDB, s
 // The method writes all (header-and-body-valid) blocks to disk, then tries to
 // switch over to the new chain if the TD exceeded the current chain.
 // insertSideChain is only used pre-merge.
-func (bc *BlockChain) insertSideChain(block *types.Block, it *insertIterator) (int, error) {
+func (bc *BlockChain) insertSideChain(block *types.Block, it *insertIterator, makeWitness bool) (*stateless.Witness, int, error) {
 	var (
 		externTd *big.Int
 		current  = bc.CurrentBlock()
@@ -2000,7 +2030,7 @@ func (bc *BlockChain) insertSideChain(block *types.Block, it *insertIterator) (i
 				// If someone legitimately side-mines blocks, they would still be imported as usual. However,
 				// we cannot risk writing unverified blocks to disk when they obviously target the pruning
 				// mechanism.
-				return it.index, errors.New("sidechain ghost-state attack")
+				return nil, it.index, errors.New("sidechain ghost-state attack")
 			}
 		}
 		if externTd == nil {
@@ -2011,7 +2041,7 @@ func (bc *BlockChain) insertSideChain(block *types.Block, it *insertIterator) (i
 		if !bc.HasBlock(block.Hash(), block.NumberU64()) {
 			start := time.Now()
 			if err := bc.writeBlockWithoutState(block, externTd); err != nil {
-				return it.index, err
+				return nil, it.index, err
 			}
 			log.Debug("Injected sidechain block", "number", block.Number(), "hash", block.Hash(),
 				"diff", block.Difficulty(), "elapsed", common.PrettyDuration(time.Since(start)),
@@ -2028,7 +2058,7 @@ func (bc *BlockChain) insertSideChain(block *types.Block, it *insertIterator) (i
 	for parent != nil && !bc.HasState(parent.Root) {
 		if bc.stateRecoverable(parent.Root) {
 			if err := bc.triedb.Recover(parent.Root); err != nil {
-				return 0, err
+				return nil, 0, err
 			}
 			break
 		}
@@ -2038,7 +2068,7 @@ func (bc *BlockChain) insertSideChain(block *types.Block, it *insertIterator) (i
 		parent = bc.GetHeader(parent.ParentHash, parent.Number.Uint64()-1)
 	}
 	if parent == nil {
-		return it.index, errors.New("missing parent")
+		return nil, it.index, errors.New("missing parent")
 	}
 	// Import all the pruned blocks to make the state available
 	var (
@@ -2057,23 +2087,23 @@ func (bc *BlockChain) insertSideChain(block *types.Block, it *insertIterator) (i
 		// memory here.
 		if len(blocks) >= 2048 || memory > 64*1024*1024 {
 			log.Info("Importing heavy sidechain segment", "blocks", len(blocks), "start", blocks[0].NumberU64(), "end", block.NumberU64())
-			if _, err := bc.insertChain(blocks, true); err != nil {
-				return 0, err
+			if _, _, err := bc.insertChain(blocks, true, false); err != nil {
+				return nil, 0, err
 			}
 			blocks, memory = blocks[:0], 0
 
 			// If the chain is terminating, stop processing blocks
 			if bc.insertStopped() {
 				log.Debug("Abort during blocks processing")
-				return 0, nil
+				return nil, 0, nil
 			}
 		}
 	}
 	if len(blocks) > 0 {
 		log.Info("Importing sidechain segment", "start", blocks[0].NumberU64(), "end", blocks[len(blocks)-1].NumberU64())
-		return bc.insertChain(blocks, true)
+		return bc.insertChain(blocks, true, makeWitness)
 	}
-	return 0, nil
+	return nil, 0, nil
 }
 
 // recoverAncestors finds the closest ancestor with available state and re-execute
@@ -2120,7 +2150,7 @@ func (bc *BlockChain) recoverAncestors(block *types.Block) (common.Hash, error)
 		} else {
 			b = bc.GetBlock(hashes[i], numbers[i])
 		}
-		if _, err := bc.insertChain(types.Blocks{b}, false); err != nil {
+		if _, _, err := bc.insertChain(types.Blocks{b}, false, false); err != nil {
 			return b.ParentHash(), err
 		}
 	}
@@ -2336,14 +2366,14 @@ func (bc *BlockChain) reorg(oldHead *types.Header, newHead *types.Block) error {
 // The key difference between the InsertChain is it won't do the canonical chain
 // updating. It relies on the additional SetCanonical call to finalize the entire
 // procedure.
-func (bc *BlockChain) InsertBlockWithoutSetHead(block *types.Block) error {
+func (bc *BlockChain) InsertBlockWithoutSetHead(block *types.Block, makeWitness bool) (*stateless.Witness, error) {
 	if !bc.chainmu.TryLock() {
-		return errChainStopped
+		return nil, errChainStopped
 	}
 	defer bc.chainmu.Unlock()
 
-	_, err := bc.insertChain(types.Blocks{block}, false)
-	return err
+	witness, _, err := bc.insertChain(types.Blocks{block}, false, makeWitness)
+	return witness, err
 }
 
 // SetCanonical rewinds the chain to set the new head block as the specified

core/blockchain_test.go

@@ -3674,7 +3674,7 @@ func testSetCanonical(t *testing.T, scheme string) {
 		gen.AddTx(tx)
 	})
 	for _, block := range side {
-		err := chain.InsertBlockWithoutSetHead(block)
+		_, err := chain.InsertBlockWithoutSetHead(block, false)
 		if err != nil {
 			t.Fatalf("Failed to insert into chain: %v", err)
 		}

core/stateless.go

@@ -25,21 +25,30 @@ import (
 	"github.com/ethereum/go-ethereum/core/stateless"
 	"github.com/ethereum/go-ethereum/core/types"
 	"github.com/ethereum/go-ethereum/core/vm"
+	"github.com/ethereum/go-ethereum/log"
 	"github.com/ethereum/go-ethereum/params"
 	"github.com/ethereum/go-ethereum/trie"
 	"github.com/ethereum/go-ethereum/triedb"
 )
 
 // ExecuteStateless runs a stateless execution based on a witness, verifies
-// everything it can locally and returns the two computed fields that need the
-// other side to explicitly check.
+// everything it can locally and returns the state root and receipt root, that
+// need the other side to explicitly check.
 //
 // This method is a bit of a sore thumb here, but:
 //   - It cannot be placed in core/stateless, because state.New prodces a circular dep
 //   - It cannot be placed outside of core, because it needs to construct a dud headerchain
 //
 // TODO(karalabe): Would be nice to resolve both issues above somehow and move it.
-func ExecuteStateless(config *params.ChainConfig, witness *stateless.Witness) (common.Hash, common.Hash, error) {
+func ExecuteStateless(config *params.ChainConfig, block *types.Block, witness *stateless.Witness) (common.Hash, common.Hash, error) {
+	// Sanity check if the supplied block accidentally contains a set root or
+	// receipt hash. If so, be very loud, but still continue.
+	if block.Root() != (common.Hash{}) {
+		log.Error("stateless runner received state root it's expected to calculate (faulty consensus client)", "block", block.Number())
+	}
+	if block.ReceiptHash() != (common.Hash{}) {
+		log.Error("stateless runner received receipt root it's expected to calculate (faulty consensus client)", "block", block.Number())
+	}
 	// Create and populate the state database to serve as the stateless backend
 	memdb := witness.MakeHashDB()
 	db, err := state.New(witness.Root(), state.NewDatabase(triedb.NewDatabase(memdb, triedb.HashDefaults), nil))
@@ -57,16 +66,15 @@ func ExecuteStateless(config *params.ChainConfig, witness *stateless.Witness) (c
 	validator := NewBlockValidator(config, nil) // No chain, we only validate the state, not the block
 
 	// Run the stateless blocks processing and self-validate certain fields
-	res, err := processor.Process(witness.Block, db, vm.Config{})
+	res, err := processor.Process(block, db, vm.Config{})
 	if err != nil {
 		return common.Hash{}, common.Hash{}, err
 	}
-	if err = validator.ValidateState(witness.Block, db, res, true); err != nil {
+	if err = validator.ValidateState(block, db, res, true); err != nil {
 		return common.Hash{}, common.Hash{}, err
 	}
 	// Almost everything validated, but receipt and state root needs to be returned
 	receiptRoot := types.DeriveSha(res.Receipts, trie.NewStackTrie(nil))
-	stateRoot := db.IntermediateRoot(config.IsEIP158(witness.Block.Number()))
-
-	return receiptRoot, stateRoot, nil
+	stateRoot := db.IntermediateRoot(config.IsEIP158(block.Number()))
+	return stateRoot, receiptRoot, nil
 }

core/stateless/database.go

@@ -26,6 +26,13 @@ import (
 // MakeHashDB imports tries, codes and block hashes from a witness into a new
 // hash-based memory db. We could eventually rewrite this into a pathdb, but
 // simple is better for now.
+//
+// Note, this hashdb approach is quite strictly self-validating:
+//   - Headers are persisted keyed by hash, so blockhash will error on junk
+//   - Codes are persisted keyed by hash, so bytecode lookup will error on junk
+//   - Trie nodes are persisted keyed by hash, so trie expansion will error on junk
+//
+// Acceleration structures built would need to explicitly validate the witness.
 func (w *Witness) MakeHashDB() ethdb.Database {
 	var (
 		memdb  = rawdb.NewMemoryDatabase()

core/stateless/encoding.go

@@ -17,42 +17,31 @@
 package stateless
 
 import (
-	"bytes"
-	"errors"
-	"fmt"
 	"io"
-	"slices"
 
-	"github.com/ethereum/go-ethereum/common/hexutil"
 	"github.com/ethereum/go-ethereum/core/types"
 	"github.com/ethereum/go-ethereum/rlp"
 )
 
-//go:generate go run github.com/fjl/gencodec -type extWitness -field-override extWitnessMarshalling -out gen_encoding_json.go
-
 // toExtWitness converts our internal witness representation to the consensus one.
 func (w *Witness) toExtWitness() *extWitness {
 	ext := &extWitness{
-		Block:   w.Block,
 		Headers: w.Headers,
 	}
 	ext.Codes = make([][]byte, 0, len(w.Codes))
 	for code := range w.Codes {
 		ext.Codes = append(ext.Codes, []byte(code))
 	}
-	slices.SortFunc(ext.Codes, bytes.Compare)
-
 	ext.State = make([][]byte, 0, len(w.State))
 	for node := range w.State {
 		ext.State = append(ext.State, []byte(node))
 	}
-	slices.SortFunc(ext.State, bytes.Compare)
 	return ext
 }
 
 // fromExtWitness converts the consensus witness format into our internal one.
 func (w *Witness) fromExtWitness(ext *extWitness) error {
-	w.Block, w.Headers = ext.Block, ext.Headers
+	w.Headers = ext.Headers
 
 	w.Codes = make(map[string]struct{}, len(ext.Codes))
 	for _, code := range ext.Codes {
@@ -62,12 +51,7 @@ func (w *Witness) fromExtWitness(ext *extWitness) error {
 	for _, node := range ext.State {
 		w.State[string(node)] = struct{}{}
 	}
-	return w.sanitize()
-}
-
-// MarshalJSON marshals a witness as JSON.
-func (w *Witness) MarshalJSON() ([]byte, error) {
-	return w.toExtWitness().MarshalJSON()
+	return nil
 }
 
 // EncodeRLP serializes a witness as RLP.
@@ -75,15 +59,6 @@ func (w *Witness) EncodeRLP(wr io.Writer) error {
 	return rlp.Encode(wr, w.toExtWitness())
 }
 
-// UnmarshalJSON unmarshals from JSON.
-func (w *Witness) UnmarshalJSON(input []byte) error {
-	var ext extWitness
-	if err := ext.UnmarshalJSON(input); err != nil {
-		return err
-	}
-	return w.fromExtWitness(&ext)
-}
-
 // DecodeRLP decodes a witness from RLP.
 func (w *Witness) DecodeRLP(s *rlp.Stream) error {
 	var ext extWitness
@@ -93,37 +68,9 @@ func (w *Witness) DecodeRLP(s *rlp.Stream) error {
 	return w.fromExtWitness(&ext)
 }
 
-// sanitize checks for some mandatory fields in the witness after decoding so
-// the rest of the code can assume invariants and doesn't have to deal with
-// corrupted data.
-func (w *Witness) sanitize() error {
-	// Verify that the "parent" header (i.e. index 0) is available, and is the
-	// true parent of the block-to-be executed, since we use that to link the
-	// current block to the pre-state.
-	if len(w.Headers) == 0 {
-		return errors.New("parent header (for pre-root hash) missing")
-	}
-	for i, header := range w.Headers {
-		if header == nil {
-			return fmt.Errorf("witness header nil at position %d", i)
-		}
-	}
-	if w.Headers[0].Hash() != w.Block.ParentHash() {
-		return fmt.Errorf("parent hash different: witness %v, block parent %v", w.Headers[0].Hash(), w.Block.ParentHash())
-	}
-	return nil
-}
-
 // extWitness is a witness RLP encoding for transferring across clients.
 type extWitness struct {
-	Block   *types.Block    `json:"block"       gencodec:"required"`
-	Headers []*types.Header `json:"headers"       gencodec:"required"`
-	Codes   [][]byte        `json:"codes"`
-	State   [][]byte        `json:"state"`
-}
-
-// extWitnessMarshalling defines the hex marshalling types for a witness.
-type extWitnessMarshalling struct {
-	Codes []hexutil.Bytes
-	State []hexutil.Bytes
+	Headers []*types.Header
+	Codes   [][]byte
+	State   [][]byte
 }

core/stateless/gen_encoding_json.go

@@ -1,74 +0,0 @@
-// Code generated by github.com/fjl/gencodec. DO NOT EDIT.
-
-package stateless
-
-import (
-	"encoding/json"
-	"errors"
-
-	"github.com/ethereum/go-ethereum/common/hexutil"
-	"github.com/ethereum/go-ethereum/core/types"
-)
-
-var _ = (*extWitnessMarshalling)(nil)
-
-// MarshalJSON marshals as JSON.
-func (e extWitness) MarshalJSON() ([]byte, error) {
-	type extWitness struct {
-		Block   *types.Block    `json:"block"       gencodec:"required"`
-		Headers []*types.Header `json:"headers"       gencodec:"required"`
-		Codes   []hexutil.Bytes `json:"codes"`
-		State   []hexutil.Bytes `json:"state"`
-	}
-	var enc extWitness
-	enc.Block = e.Block
-	enc.Headers = e.Headers
-	if e.Codes != nil {
-		enc.Codes = make([]hexutil.Bytes, len(e.Codes))
-		for k, v := range e.Codes {
-			enc.Codes[k] = v
-		}
-	}
-	if e.State != nil {
-		enc.State = make([]hexutil.Bytes, len(e.State))
-		for k, v := range e.State {
-			enc.State[k] = v
-		}
-	}
-	return json.Marshal(&enc)
-}
-
-// UnmarshalJSON unmarshals from JSON.
-func (e *extWitness) UnmarshalJSON(input []byte) error {
-	type extWitness struct {
-		Block   *types.Block    `json:"block"       gencodec:"required"`
-		Headers []*types.Header `json:"headers"       gencodec:"required"`
-		Codes   []hexutil.Bytes `json:"codes"`
-		State   []hexutil.Bytes `json:"state"`
-	}
-	var dec extWitness
-	if err := json.Unmarshal(input, &dec); err != nil {
-		return err
-	}
-	if dec.Block == nil {
-		return errors.New("missing required field 'block' for extWitness")
-	}
-	e.Block = dec.Block
-	if dec.Headers == nil {
-		return errors.New("missing required field 'headers' for extWitness")
-	}
-	e.Headers = dec.Headers
-	if dec.Codes != nil {
-		e.Codes = make([][]byte, len(dec.Codes))
-		for k, v := range dec.Codes {
-			e.Codes[k] = v
-		}
-	}
-	if dec.State != nil {
-		e.State = make([][]byte, len(dec.State))
-		for k, v := range dec.State {
-			e.State[k] = v
-		}
-	}
-	return nil
-}

core/stateless/witness.go

@@ -17,16 +17,13 @@
 package stateless
 
 import (
-	"bytes"
 	"errors"
-	"fmt"
 	"maps"
 	"slices"
 	"sync"
 
 	"github.com/ethereum/go-ethereum/common"
 	"github.com/ethereum/go-ethereum/core/types"
-	"github.com/ethereum/go-ethereum/rlp"
 )
 
 // HeaderReader is an interface to pull in headers in place of block hashes for
@@ -36,10 +33,11 @@ type HeaderReader interface {
 	GetHeader(hash common.Hash, number uint64) *types.Header
 }
 
-// Witness encompasses a block, state and any other chain data required to apply
-// a set of transactions and derive a post state/receipt root.
+// Witness encompasses the state required to apply a set of transactions and
+// derive a post state/receipt root.
 type Witness struct {
-	Block   *types.Block        // Current block with rootHash and receiptHash zeroed out
+	context *types.Header // Header to which this witness belongs to, with rootHash and receiptHash zeroed out
+
 	Headers []*types.Header     // Past headers in reverse order (0=parent, 1=parent's-parent, etc). First *must* be set.
 	Codes   map[string]struct{} // Set of bytecodes ran or accessed
 	State   map[string]struct{} // Set of MPT state trie nodes (account and storage together)
@@ -49,24 +47,23 @@ type Witness struct {
 }
 
 // NewWitness creates an empty witness ready for population.
-func NewWitness(chain HeaderReader, block *types.Block) (*Witness, error) {
-	// Zero out the result fields to avoid accidentally sending them to the verifier
-	header := block.Header()
-	header.Root = common.Hash{}
-	header.ReceiptHash = common.Hash{}
-
-	// Retrieve the parent header, which will *always* be included to act as a
-	// trustless pre-root hash container
-	parent := chain.GetHeader(block.ParentHash(), block.NumberU64()-1)
+func NewWitness(context *types.Header, chain HeaderReader) (*Witness, error) {
+	// When building witnesses, retrieve the parent header, which will *always*
+	// be included to act as a trustless pre-root hash container
+	var headers []*types.Header
+	if chain != nil {
+		parent := chain.GetHeader(context.ParentHash, context.Number.Uint64()-1)
 		if parent == nil {
 			return nil, errors.New("failed to retrieve parent header")
 		}
+		headers = append(headers, parent)
+	}
 	// Create the wtness with a reconstructed gutted out block
 	return &Witness{
-		Block:   types.NewBlockWithHeader(header).WithBody(*block.Body()),
+		context: context,
+		Headers: headers,
 		Codes:   make(map[string]struct{}),
 		State:   make(map[string]struct{}),
-		Headers: []*types.Header{parent},
 		chain:   chain,
 	}, nil
 }
@@ -76,11 +73,8 @@ func NewWitness(chain HeaderReader, block *types.Block) (*Witness, error) {
 // the chain to cover the block being added.
 func (w *Witness) AddBlockHash(number uint64) {
 	// Keep pulling in headers until this hash is populated
-	for int(w.Block.NumberU64()-number) > len(w.Headers) {
-		tail := w.Block.Header()
-		if len(w.Headers) > 0 {
-			tail = w.Headers[len(w.Headers)-1]
-		}
+	for int(w.context.Number.Uint64()-number) > len(w.Headers) {
+		tail := w.Headers[len(w.Headers)-1]
 		w.Headers = append(w.Headers, w.chain.GetHeader(tail.ParentHash, tail.Number.Uint64()-1))
 	}
 }
@@ -107,45 +101,16 @@ func (w *Witness) AddState(nodes map[string]struct{}) {
 // Copy deep-copies the witness object.  Witness.Block isn't deep-copied as it
 // is never mutated by Witness
 func (w *Witness) Copy() *Witness {
-	return &Witness{
-		Block:   w.Block,
+	cpy := &Witness{
 		Headers: slices.Clone(w.Headers),
 		Codes:   maps.Clone(w.Codes),
 		State:   maps.Clone(w.State),
+		chain:   w.chain,
 	}
-}
-
-// String prints a human-readable summary containing the total size of the
-// witness and the sizes of the underlying components
-func (w *Witness) String() string {
-	blob, _ := rlp.EncodeToBytes(w)
-	bytesTotal := len(blob)
-
-	blob, _ = rlp.EncodeToBytes(w.Block)
-	bytesBlock := len(blob)
-
-	bytesHeaders := 0
-	for _, header := range w.Headers {
-		blob, _ = rlp.EncodeToBytes(header)
-		bytesHeaders += len(blob)
-	}
-	bytesCodes := 0
-	for code := range w.Codes {
-		bytesCodes += len(code)
+	if w.context != nil {
+		cpy.context = types.CopyHeader(w.context)
 	}
-	bytesState := 0
-	for node := range w.State {
-		bytesState += len(node)
-	}
-	buf := new(bytes.Buffer)
-
-	fmt.Fprintf(buf, "Witness #%d: %v\n", w.Block.Number(), common.StorageSize(bytesTotal))
-	fmt.Fprintf(buf, "     block (%4d txs):  %10v\n", len(w.Block.Transactions()), common.StorageSize(bytesBlock))
-	fmt.Fprintf(buf, "%4d headers:      %10v\n", len(w.Headers), common.StorageSize(bytesHeaders))
-	fmt.Fprintf(buf, "%4d trie nodes:   %10v\n", len(w.State), common.StorageSize(bytesState))
-	fmt.Fprintf(buf, "%4d codes:        %10v\n", len(w.Codes), common.StorageSize(bytesCodes))
-
-	return buf.String()
+	return cpy
 }
 
 // Root returns the pre-state root from the first header.

core/types.go

@@ -19,9 +19,7 @@ package core
 import (
 	"sync/atomic"
 
-	"github.com/ethereum/go-ethereum/common"
 	"github.com/ethereum/go-ethereum/core/state"
-	"github.com/ethereum/go-ethereum/core/stateless"
 	"github.com/ethereum/go-ethereum/core/types"
 	"github.com/ethereum/go-ethereum/core/vm"
 )
@@ -35,9 +33,6 @@ type Validator interface {
 
 	// ValidateState validates the given statedb and optionally the process result.
 	ValidateState(block *types.Block, state *state.StateDB, res *ProcessResult, stateless bool) error
-
-	// ValidateWitness cross validates a block execution with stateless remote clients.
-	ValidateWitness(witness *stateless.Witness, receiptRoot common.Hash, stateRoot common.Hash) error
 }
 
 // Prefetcher is an interface for pre-caching transaction signatures and state.

core/vm/interpreter.go

@@ -33,7 +33,8 @@ type Config struct {
 	NoBaseFee               bool  // Forces the EIP-1559 baseFee to 0 (needed for 0 price calls)
 	EnablePreimageRecording bool  // Enables recording of SHA3/keccak preimages
 	ExtraEips               []int // Additional EIPS that are to be enabled
-	EnableWitnessCollection bool  // true if witness collection is enabled
+
+	StatelessSelfValidation bool // Generate execution witnesses and self-check against them (testing purpose)
 }
 
 // ScopeContext contains the things that are per-call, such as stack and memory,

eth/backend.go

@@ -183,7 +183,6 @@ func New(stack *node.Node, config *ethconfig.Config) (*Ethereum, error) {
 	var (
 		vmConfig = vm.Config{
 			EnablePreimageRecording: config.EnablePreimageRecording,
-			EnableWitnessCollection: config.EnableWitnessCollection,
 		}
 		cacheConfig = &core.CacheConfig{
 			TrieCleanLimit:      config.TrieCleanCache,

eth/catalyst/api.go

@@ -27,7 +27,9 @@ import (
 	"github.com/ethereum/go-ethereum/beacon/engine"
 	"github.com/ethereum/go-ethereum/common"
 	"github.com/ethereum/go-ethereum/common/hexutil"
+	"github.com/ethereum/go-ethereum/core"
 	"github.com/ethereum/go-ethereum/core/rawdb"
+	"github.com/ethereum/go-ethereum/core/stateless"
 	"github.com/ethereum/go-ethereum/core/types"
 	"github.com/ethereum/go-ethereum/eth"
 	"github.com/ethereum/go-ethereum/eth/downloader"
@@ -37,6 +39,7 @@ import (
 	"github.com/ethereum/go-ethereum/node"
 	"github.com/ethereum/go-ethereum/params"
 	"github.com/ethereum/go-ethereum/params/forks"
+	"github.com/ethereum/go-ethereum/rlp"
 	"github.com/ethereum/go-ethereum/rpc"
 )
 
@@ -82,6 +85,9 @@ var caps = []string{
 	"engine_forkchoiceUpdatedV1",
 	"engine_forkchoiceUpdatedV2",
 	"engine_forkchoiceUpdatedV3",
+	"engine_forkchoiceUpdatedWithWitnessV1",
+	"engine_forkchoiceUpdatedWithWitnessV2",
+	"engine_forkchoiceUpdatedWithWitnessV3",
 	"engine_exchangeTransitionConfigurationV1",
 	"engine_getPayloadV1",
 	"engine_getPayloadV2",
@@ -91,6 +97,14 @@ var caps = []string{
 	"engine_newPayloadV2",
 	"engine_newPayloadV3",
 	"engine_newPayloadV4",
+	"engine_newPayloadWithWitnessV1",
+	"engine_newPayloadWithWitnessV2",
+	"engine_newPayloadWithWitnessV3",
+	"engine_newPayloadWithWitnessV4",
+	"engine_executeStatelessPayloadV1",
+	"engine_executeStatelessPayloadV2",
+	"engine_executeStatelessPayloadV3",
+	"engine_executeStatelessPayloadV4",
 	"engine_getPayloadBodiesByHashV1",
 	"engine_getPayloadBodiesByHashV2",
 	"engine_getPayloadBodiesByRangeV1",
@@ -188,7 +202,7 @@ func (api *ConsensusAPI) ForkchoiceUpdatedV1(update engine.ForkchoiceStateV1, pa
 			return engine.STATUS_INVALID, engine.InvalidParams.With(errors.New("forkChoiceUpdateV1 called post-shanghai"))
 		}
 	}
-	return api.forkchoiceUpdated(update, payloadAttributes, engine.PayloadV1)
+	return api.forkchoiceUpdated(update, payloadAttributes, engine.PayloadV1, false)
 }
 
 // ForkchoiceUpdatedV2 is equivalent to V1 with the addition of withdrawals in the payload
@@ -211,7 +225,7 @@ func (api *ConsensusAPI) ForkchoiceUpdatedV2(update engine.ForkchoiceStateV1, pa
 			return engine.STATUS_INVALID, engine.UnsupportedFork.With(errors.New("forkchoiceUpdatedV2 must only be called with paris and shanghai payloads"))
 		}
 	}
-	return api.forkchoiceUpdated(update, params, engine.PayloadV2)
+	return api.forkchoiceUpdated(update, params, engine.PayloadV2, false)
 }
 
 // ForkchoiceUpdatedV3 is equivalent to V2 with the addition of parent beacon block root
@@ -232,10 +246,68 @@ func (api *ConsensusAPI) ForkchoiceUpdatedV3(update engine.ForkchoiceStateV1, pa
 	// hash, even if params are wrong. To do this we need to split up
 	// forkchoiceUpdate into a function that only updates the head and then a
 	// function that kicks off block construction.
-	return api.forkchoiceUpdated(update, params, engine.PayloadV3)
+	return api.forkchoiceUpdated(update, params, engine.PayloadV3, false)
 }
 
-func (api *ConsensusAPI) forkchoiceUpdated(update engine.ForkchoiceStateV1, payloadAttributes *engine.PayloadAttributes, payloadVersion engine.PayloadVersion) (engine.ForkChoiceResponse, error) {
+// ForkchoiceUpdatedWithWitnessV1 is analogous to ForkchoiceUpdatedV1, only it
+// generates an execution witness too if block building was requested.
+func (api *ConsensusAPI) ForkchoiceUpdatedWithWitnessV1(update engine.ForkchoiceStateV1, payloadAttributes *engine.PayloadAttributes) (engine.ForkChoiceResponse, error) {
+	if payloadAttributes != nil {
+		if payloadAttributes.Withdrawals != nil || payloadAttributes.BeaconRoot != nil {
+			return engine.STATUS_INVALID, engine.InvalidParams.With(errors.New("withdrawals and beacon root not supported in V1"))
+		}
+		if api.eth.BlockChain().Config().IsShanghai(api.eth.BlockChain().Config().LondonBlock, payloadAttributes.Timestamp) {
+			return engine.STATUS_INVALID, engine.InvalidParams.With(errors.New("forkChoiceUpdateV1 called post-shanghai"))
+		}
+	}
+	return api.forkchoiceUpdated(update, payloadAttributes, engine.PayloadV1, true)
+}
+
+// ForkchoiceUpdatedWithWitnessV2 is analogous to ForkchoiceUpdatedV2, only it
+// generates an execution witness too if block building was requested.
+func (api *ConsensusAPI) ForkchoiceUpdatedWithWitnessV2(update engine.ForkchoiceStateV1, params *engine.PayloadAttributes) (engine.ForkChoiceResponse, error) {
+	if params != nil {
+		if params.BeaconRoot != nil {
+			return engine.STATUS_INVALID, engine.InvalidPayloadAttributes.With(errors.New("unexpected beacon root"))
+		}
+		switch api.eth.BlockChain().Config().LatestFork(params.Timestamp) {
+		case forks.Paris:
+			if params.Withdrawals != nil {
+				return engine.STATUS_INVALID, engine.InvalidPayloadAttributes.With(errors.New("withdrawals before shanghai"))
+			}
+		case forks.Shanghai:
+			if params.Withdrawals == nil {
+				return engine.STATUS_INVALID, engine.InvalidPayloadAttributes.With(errors.New("missing withdrawals"))
+			}
+		default:
+			return engine.STATUS_INVALID, engine.UnsupportedFork.With(errors.New("forkchoiceUpdatedV2 must only be called with paris and shanghai payloads"))
+		}
+	}
+	return api.forkchoiceUpdated(update, params, engine.PayloadV2, true)
+}
+
+// ForkchoiceUpdatedWithWitnessV3 is analogous to ForkchoiceUpdatedV3, only it
+// generates an execution witness too if block building was requested.
+func (api *ConsensusAPI) ForkchoiceUpdatedWithWitnessV3(update engine.ForkchoiceStateV1, params *engine.PayloadAttributes) (engine.ForkChoiceResponse, error) {
+	if params != nil {
+		if params.Withdrawals == nil {
+			return engine.STATUS_INVALID, engine.InvalidPayloadAttributes.With(errors.New("missing withdrawals"))
+		}
+		if params.BeaconRoot == nil {
+			return engine.STATUS_INVALID, engine.InvalidPayloadAttributes.With(errors.New("missing beacon root"))
+		}
+		if api.eth.BlockChain().Config().LatestFork(params.Timestamp) != forks.Cancun && api.eth.BlockChain().Config().LatestFork(params.Timestamp) != forks.Prague {
+			return engine.STATUS_INVALID, engine.UnsupportedFork.With(errors.New("forkchoiceUpdatedV3 must only be called for cancun payloads"))
+		}
+	}
+	// TODO(matt): the spec requires that fcu is applied when called on a valid
+	// hash, even if params are wrong. To do this we need to split up
+	// forkchoiceUpdate into a function that only updates the head and then a
+	// function that kicks off block construction.
+	return api.forkchoiceUpdated(update, params, engine.PayloadV3, true)
+}
+
+func (api *ConsensusAPI) forkchoiceUpdated(update engine.ForkchoiceStateV1, payloadAttributes *engine.PayloadAttributes, payloadVersion engine.PayloadVersion, payloadWitness bool) (engine.ForkChoiceResponse, error) {
 	api.forkchoiceLock.Lock()
 	defer api.forkchoiceLock.Unlock()
 
@@ -378,7 +450,7 @@ func (api *ConsensusAPI) forkchoiceUpdated(update engine.ForkchoiceStateV1, payl
 		if api.localBlocks.has(id) {
 			return valid(&id), nil
 		}
-		payload, err := api.eth.Miner().BuildPayload(args)
+		payload, err := api.eth.Miner().BuildPayload(args, payloadWitness)
 		if err != nil {
 			log.Error("Failed to build payload", "err", err)
 			return valid(nil), engine.InvalidPayloadAttributes.With(err)
@@ -469,7 +541,7 @@ func (api *ConsensusAPI) NewPayloadV1(params engine.ExecutableData) (engine.Payl
 	if params.Withdrawals != nil {
 		return engine.PayloadStatusV1{Status: engine.INVALID}, engine.InvalidParams.With(errors.New("withdrawals not supported in V1"))
 	}
-	return api.newPayload(params, nil, nil)
+	return api.newPayload(params, nil, nil, false)
 }
 
 // NewPayloadV2 creates an Eth1 block, inserts it in the chain, and returns the status of the chain.
@@ -492,7 +564,7 @@ func (api *ConsensusAPI) NewPayloadV2(params engine.ExecutableData) (engine.Payl
 	if params.BlobGasUsed != nil {
 		return engine.PayloadStatusV1{Status: engine.INVALID}, engine.InvalidParams.With(errors.New("non-nil blobGasUsed pre-cancun"))
 	}
-	return api.newPayload(params, nil, nil)
+	return api.newPayload(params, nil, nil, false)
 }
 
 // NewPayloadV3 creates an Eth1 block, inserts it in the chain, and returns the status of the chain.
@@ -517,9 +589,10 @@ func (api *ConsensusAPI) NewPayloadV3(params engine.ExecutableData, versionedHas
 	if api.eth.BlockChain().Config().LatestFork(params.Timestamp) != forks.Cancun {
 		return engine.PayloadStatusV1{Status: engine.INVALID}, engine.UnsupportedFork.With(errors.New("newPayloadV3 must only be called for cancun payloads"))
 	}
-	return api.newPayload(params, versionedHashes, beaconRoot)
+	return api.newPayload(params, versionedHashes, beaconRoot, false)
 }
 
+// NewPayloadV4 creates an Eth1 block, inserts it in the chain, and returns the status of the chain.
 // NewPayloadV4 creates an Eth1 block, inserts it in the chain, and returns the status of the chain.
 func (api *ConsensusAPI) NewPayloadV4(params engine.ExecutableData, versionedHashes []common.Hash, beaconRoot *common.Hash) (engine.PayloadStatusV1, error) {
 	if params.Withdrawals == nil {
@@ -545,10 +618,186 @@ func (api *ConsensusAPI) NewPayloadV4(params engine.ExecutableData, versionedHas
 	if api.eth.BlockChain().Config().LatestFork(params.Timestamp) != forks.Prague {
 		return engine.PayloadStatusV1{Status: engine.INVALID}, engine.UnsupportedFork.With(errors.New("newPayloadV4 must only be called for prague payloads"))
 	}
-	return api.newPayload(params, versionedHashes, beaconRoot)
+	return api.newPayload(params, versionedHashes, beaconRoot, false)
 }
 
-func (api *ConsensusAPI) newPayload(params engine.ExecutableData, versionedHashes []common.Hash, beaconRoot *common.Hash) (engine.PayloadStatusV1, error) {
+// NewPayloadWithWitnessV1 is analogous to NewPayloadV1, only it also generates
+// and returns a stateless witness after running the payload.
+func (api *ConsensusAPI) NewPayloadWithWitnessV1(params engine.ExecutableData) (engine.PayloadStatusV1, error) {
+	if params.Withdrawals != nil {
+		return engine.PayloadStatusV1{Status: engine.INVALID}, engine.InvalidParams.With(errors.New("withdrawals not supported in V1"))
+	}
+	return api.newPayload(params, nil, nil, true)
+}
+
+// NewPayloadWithWitnessV2 is analogous to NewPayloadV2, only it also generates
+// and returns a stateless witness after running the payload.
+func (api *ConsensusAPI) NewPayloadWithWitnessV2(params engine.ExecutableData) (engine.PayloadStatusV1, error) {
+	if api.eth.BlockChain().Config().IsCancun(api.eth.BlockChain().Config().LondonBlock, params.Timestamp) {
+		return engine.PayloadStatusV1{Status: engine.INVALID}, engine.InvalidParams.With(errors.New("can't use newPayloadV2 post-cancun"))
+	}
+	if api.eth.BlockChain().Config().LatestFork(params.Timestamp) == forks.Shanghai {
+		if params.Withdrawals == nil {
+			return engine.PayloadStatusV1{Status: engine.INVALID}, engine.InvalidParams.With(errors.New("nil withdrawals post-shanghai"))
+		}
+	} else {
+		if params.Withdrawals != nil {
+			return engine.PayloadStatusV1{Status: engine.INVALID}, engine.InvalidParams.With(errors.New("non-nil withdrawals pre-shanghai"))
+		}
+	}
+	if params.ExcessBlobGas != nil {
+		return engine.PayloadStatusV1{Status: engine.INVALID}, engine.InvalidParams.With(errors.New("non-nil excessBlobGas pre-cancun"))
+	}
+	if params.BlobGasUsed != nil {
+		return engine.PayloadStatusV1{Status: engine.INVALID}, engine.InvalidParams.With(errors.New("non-nil blobGasUsed pre-cancun"))
+	}
+	return api.newPayload(params, nil, nil, true)
+}
+
+// NewPayloadWithWitnessV3 is analogous to NewPayloadV3, only it also generates
+// and returns a stateless witness after running the payload.
+func (api *ConsensusAPI) NewPayloadWithWitnessV3(params engine.ExecutableData, versionedHashes []common.Hash, beaconRoot *common.Hash) (engine.PayloadStatusV1, error) {
+	if params.Withdrawals == nil {
+		return engine.PayloadStatusV1{Status: engine.INVALID}, engine.InvalidParams.With(errors.New("nil withdrawals post-shanghai"))
+	}
+	if params.ExcessBlobGas == nil {
+		return engine.PayloadStatusV1{Status: engine.INVALID}, engine.InvalidParams.With(errors.New("nil excessBlobGas post-cancun"))
+	}
+	if params.BlobGasUsed == nil {
+		return engine.PayloadStatusV1{Status: engine.INVALID}, engine.InvalidParams.With(errors.New("nil blobGasUsed post-cancun"))
+	}
+
+	if versionedHashes == nil {
+		return engine.PayloadStatusV1{Status: engine.INVALID}, engine.InvalidParams.With(errors.New("nil versionedHashes post-cancun"))
+	}
+	if beaconRoot == nil {
+		return engine.PayloadStatusV1{Status: engine.INVALID}, engine.InvalidParams.With(errors.New("nil beaconRoot post-cancun"))
+	}
+
+	if api.eth.BlockChain().Config().LatestFork(params.Timestamp) != forks.Cancun {
+		return engine.PayloadStatusV1{Status: engine.INVALID}, engine.UnsupportedFork.With(errors.New("newPayloadWithWitnessV3 must only be called for cancun payloads"))
+	}
+	return api.newPayload(params, versionedHashes, beaconRoot, true)
+}
+
+// NewPayloadWithWitnessV4 is analogous to NewPayloadV4, only it also generates
+// and returns a stateless witness after running the payload.
+func (api *ConsensusAPI) NewPayloadWithWitnessV4(params engine.ExecutableData, versionedHashes []common.Hash, beaconRoot *common.Hash) (engine.PayloadStatusV1, error) {
+	if params.Withdrawals == nil {
+		return engine.PayloadStatusV1{Status: engine.INVALID}, engine.InvalidParams.With(errors.New("nil withdrawals post-shanghai"))
+	}
+	if params.ExcessBlobGas == nil {
+		return engine.PayloadStatusV1{Status: engine.INVALID}, engine.InvalidParams.With(errors.New("nil excessBlobGas post-cancun"))
+	}
+	if params.BlobGasUsed == nil {
+		return engine.PayloadStatusV1{Status: engine.INVALID}, engine.InvalidParams.With(errors.New("nil blobGasUsed post-cancun"))
+	}
+	if params.Deposits == nil {
+		return engine.PayloadStatusV1{Status: engine.INVALID}, engine.InvalidParams.With(errors.New("nil deposits post-prague"))
+	}
+
+	if versionedHashes == nil {
+		return engine.PayloadStatusV1{Status: engine.INVALID}, engine.InvalidParams.With(errors.New("nil versionedHashes post-cancun"))
+	}
+	if beaconRoot == nil {
+		return engine.PayloadStatusV1{Status: engine.INVALID}, engine.InvalidParams.With(errors.New("nil beaconRoot post-cancun"))
+	}
+
+	if api.eth.BlockChain().Config().LatestFork(params.Timestamp) != forks.Prague {
+		return engine.PayloadStatusV1{Status: engine.INVALID}, engine.UnsupportedFork.With(errors.New("newPayloadWithWitnessV4 must only be called for prague payloads"))
+	}
+	return api.newPayload(params, versionedHashes, beaconRoot, true)
+}
+
+// ExecuteStatelessPayloadV1 is analogous to NewPayloadV1, only it operates in
+// a stateless mode on top of a provided witness instead of the local database.
+func (api *ConsensusAPI) ExecuteStatelessPayloadV1(params engine.ExecutableData, opaqueWitness hexutil.Bytes) (engine.StatelessPayloadStatusV1, error) {
+	if params.Withdrawals != nil {
+		return engine.StatelessPayloadStatusV1{Status: engine.INVALID}, engine.InvalidParams.With(errors.New("withdrawals not supported in V1"))
+	}
+	return api.executeStatelessPayload(params, nil, nil, opaqueWitness)
+}
+
+// ExecuteStatelessPayloadV2 is analogous to NewPayloadV2, only it operates in
+// a stateless mode on top of a provided witness instead of the local database.
+func (api *ConsensusAPI) ExecuteStatelessPayloadV2(params engine.ExecutableData, opaqueWitness hexutil.Bytes) (engine.StatelessPayloadStatusV1, error) {
+	if api.eth.BlockChain().Config().IsCancun(api.eth.BlockChain().Config().LondonBlock, params.Timestamp) {
+		return engine.StatelessPayloadStatusV1{Status: engine.INVALID}, engine.InvalidParams.With(errors.New("can't use newPayloadV2 post-cancun"))
+	}
+	if api.eth.BlockChain().Config().LatestFork(params.Timestamp) == forks.Shanghai {
+		if params.Withdrawals == nil {
+			return engine.StatelessPayloadStatusV1{Status: engine.INVALID}, engine.InvalidParams.With(errors.New("nil withdrawals post-shanghai"))
+		}
+	} else {
+		if params.Withdrawals != nil {
+			return engine.StatelessPayloadStatusV1{Status: engine.INVALID}, engine.InvalidParams.With(errors.New("non-nil withdrawals pre-shanghai"))
+		}
+	}
+	if params.ExcessBlobGas != nil {
+		return engine.StatelessPayloadStatusV1{Status: engine.INVALID}, engine.InvalidParams.With(errors.New("non-nil excessBlobGas pre-cancun"))
+	}
+	if params.BlobGasUsed != nil {
+		return engine.StatelessPayloadStatusV1{Status: engine.INVALID}, engine.InvalidParams.With(errors.New("non-nil blobGasUsed pre-cancun"))
+	}
+	return api.executeStatelessPayload(params, nil, nil, opaqueWitness)
+}
+
+// ExecuteStatelessPayloadV3 is analogous to NewPayloadV3, only it operates in
+// a stateless mode on top of a provided witness instead of the local database.
+func (api *ConsensusAPI) ExecuteStatelessPayloadV3(params engine.ExecutableData, versionedHashes []common.Hash, beaconRoot *common.Hash, opaqueWitness hexutil.Bytes) (engine.StatelessPayloadStatusV1, error) {
+	if params.Withdrawals == nil {
+		return engine.StatelessPayloadStatusV1{Status: engine.INVALID}, engine.InvalidParams.With(errors.New("nil withdrawals post-shanghai"))
+	}
+	if params.ExcessBlobGas == nil {
+		return engine.StatelessPayloadStatusV1{Status: engine.INVALID}, engine.InvalidParams.With(errors.New("nil excessBlobGas post-cancun"))
+	}
+	if params.BlobGasUsed == nil {
+		return engine.StatelessPayloadStatusV1{Status: engine.INVALID}, engine.InvalidParams.With(errors.New("nil blobGasUsed post-cancun"))
+	}
+
+	if versionedHashes == nil {
+		return engine.StatelessPayloadStatusV1{Status: engine.INVALID}, engine.InvalidParams.With(errors.New("nil versionedHashes post-cancun"))
+	}
+	if beaconRoot == nil {
+		return engine.StatelessPayloadStatusV1{Status: engine.INVALID}, engine.InvalidParams.With(errors.New("nil beaconRoot post-cancun"))
+	}
+
+	if api.eth.BlockChain().Config().LatestFork(params.Timestamp) != forks.Cancun {
+		return engine.StatelessPayloadStatusV1{Status: engine.INVALID}, engine.UnsupportedFork.With(errors.New("executeStatelessPayloadV3 must only be called for cancun payloads"))
+	}
+	return api.executeStatelessPayload(params, versionedHashes, beaconRoot, opaqueWitness)
+}
+
+// ExecuteStatelessPayloadV4 is analogous to NewPayloadV4, only it operates in
+// a stateless mode on top of a provided witness instead of the local database.
+func (api *ConsensusAPI) ExecuteStatelessPayloadV4(params engine.ExecutableData, versionedHashes []common.Hash, beaconRoot *common.Hash, opaqueWitness hexutil.Bytes) (engine.StatelessPayloadStatusV1, error) {
+	if params.Withdrawals == nil {
+		return engine.StatelessPayloadStatusV1{Status: engine.INVALID}, engine.InvalidParams.With(errors.New("nil withdrawals post-shanghai"))
+	}
+	if params.ExcessBlobGas == nil {
+		return engine.StatelessPayloadStatusV1{Status: engine.INVALID}, engine.InvalidParams.With(errors.New("nil excessBlobGas post-cancun"))
+	}
+	if params.BlobGasUsed == nil {
+		return engine.StatelessPayloadStatusV1{Status: engine.INVALID}, engine.InvalidParams.With(errors.New("nil blobGasUsed post-cancun"))
+	}
+	if params.Deposits == nil {
+		return engine.StatelessPayloadStatusV1{Status: engine.INVALID}, engine.InvalidParams.With(errors.New("nil deposits post-prague"))
+	}
+
+	if versionedHashes == nil {
+		return engine.StatelessPayloadStatusV1{Status: engine.INVALID}, engine.InvalidParams.With(errors.New("nil versionedHashes post-cancun"))
+	}
+	if beaconRoot == nil {
+		return engine.StatelessPayloadStatusV1{Status: engine.INVALID}, engine.InvalidParams.With(errors.New("nil beaconRoot post-cancun"))
+	}
+
+	if api.eth.BlockChain().Config().LatestFork(params.Timestamp) != forks.Prague {
+		return engine.StatelessPayloadStatusV1{Status: engine.INVALID}, engine.UnsupportedFork.With(errors.New("executeStatelessPayloadV4 must only be called for prague payloads"))
+	}
+	return api.executeStatelessPayload(params, versionedHashes, beaconRoot, opaqueWitness)
+}
+
+func (api *ConsensusAPI) newPayload(params engine.ExecutableData, versionedHashes []common.Hash, beaconRoot *common.Hash, witness bool) (engine.PayloadStatusV1, error) {
 	// The locking here is, strictly, not required. Without these locks, this can happen:
 	//
 	// 1. NewPayload( execdata-N ) is invoked from the CL. It goes all the way down to
@@ -656,8 +905,9 @@ func (api *ConsensusAPI) newPayload(params engine.ExecutableData, versionedHashe
 		return engine.PayloadStatusV1{Status: engine.ACCEPTED}, nil
 	}
 	log.Trace("Inserting block without sethead", "hash", block.Hash(), "number", block.Number())
-	if err := api.eth.BlockChain().InsertBlockWithoutSetHead(block); err != nil {
-		log.Warn("NewPayloadV1: inserting block failed", "error", err)
+	proofs, err := api.eth.BlockChain().InsertBlockWithoutSetHead(block, witness)
+	if err != nil {
+		log.Warn("NewPayload: inserting block failed", "error", err)
 
 		api.invalidLock.Lock()
 		api.invalidBlocksHits[block.Hash()] = 1
@@ -667,7 +917,71 @@ func (api *ConsensusAPI) newPayload(params engine.ExecutableData, versionedHashe
 		return api.invalid(err, parent.Header()), nil
 	}
 	hash := block.Hash()
-	return engine.PayloadStatusV1{Status: engine.VALID, LatestValidHash: &hash}, nil
+
+	// If witness collection was requested, inject that into the result too
+	var ow *hexutil.Bytes
+	if proofs != nil {
+		ow = new(hexutil.Bytes)
+		*ow, _ = rlp.EncodeToBytes(proofs)
+	}
+	return engine.PayloadStatusV1{Status: engine.VALID, Witness: ow, LatestValidHash: &hash}, nil
+}
+
+func (api *ConsensusAPI) executeStatelessPayload(params engine.ExecutableData, versionedHashes []common.Hash, beaconRoot *common.Hash, opaqueWitness hexutil.Bytes) (engine.StatelessPayloadStatusV1, error) {
+	log.Trace("Engine API request received", "method", "ExecuteStatelessPayload", "number", params.Number, "hash", params.BlockHash)
+
+	block, err := engine.ExecutableDataToBlockNoHash(params, versionedHashes, beaconRoot)
+	if err != nil {
+		bgu := "nil"
+		if params.BlobGasUsed != nil {
+			bgu = strconv.Itoa(int(*params.BlobGasUsed))
+		}
+		ebg := "nil"
+		if params.ExcessBlobGas != nil {
+			ebg = strconv.Itoa(int(*params.ExcessBlobGas))
+		}
+		log.Warn("Invalid ExecuteStatelessPayload params",
+			"params.Number", params.Number,
+			"params.ParentHash", params.ParentHash,
+			"params.BlockHash", params.BlockHash,
+			"params.StateRoot", params.StateRoot,
+			"params.FeeRecipient", params.FeeRecipient,
+			"params.LogsBloom", common.PrettyBytes(params.LogsBloom),
+			"params.Random", params.Random,
+			"params.GasLimit", params.GasLimit,
+			"params.GasUsed", params.GasUsed,
+			"params.Timestamp", params.Timestamp,
+			"params.ExtraData", common.PrettyBytes(params.ExtraData),
+			"params.BaseFeePerGas", params.BaseFeePerGas,
+			"params.BlobGasUsed", bgu,
+			"params.ExcessBlobGas", ebg,
+			"len(params.Transactions)", len(params.Transactions),
+			"len(params.Withdrawals)", len(params.Withdrawals),
+			"len(params.Deposits)", len(params.Deposits),
+			"beaconRoot", beaconRoot,
+			"error", err)
+		errorMsg := err.Error()
+		return engine.StatelessPayloadStatusV1{Status: engine.INVALID, ValidationError: &errorMsg}, nil
+	}
+	witness := new(stateless.Witness)
+	if err := rlp.DecodeBytes(opaqueWitness, witness); err != nil {
+		log.Warn("Invalid ExecuteStatelessPayload witness", "err", err)
+		errorMsg := err.Error()
+		return engine.StatelessPayloadStatusV1{Status: engine.INVALID, ValidationError: &errorMsg}, nil
+	}
+	// Stash away the last update to warn the user if the beacon client goes offline
+	api.lastNewPayloadLock.Lock()
+	api.lastNewPayloadUpdate = time.Now()
+	api.lastNewPayloadLock.Unlock()
+
+	log.Trace("Executing block statelessly", "number", block.Number(), "hash", params.BlockHash)
+	stateRoot, receiptRoot, err := core.ExecuteStateless(api.eth.BlockChain().Config(), block, witness)
+	if err != nil {
+		log.Warn("ExecuteStatelessPayload: execution failed", "err", err)
+		errorMsg := err.Error()
+		return engine.StatelessPayloadStatusV1{Status: engine.INVALID, ValidationError: &errorMsg}, nil
+	}
+	return engine.StatelessPayloadStatusV1{Status: engine.VALID, StateRoot: stateRoot, ReceiptsRoot: receiptRoot}, nil
 }
 
 // delayPayloadImport stashes the given block away for import at a later time,

eth/catalyst/api_test.go

@@ -507,7 +507,7 @@ func setupBlocks(t *testing.T, ethservice *eth.Ethereum, n int, parent *types.He
 		}
 
 		payload := getNewPayload(t, api, parent, w, h)
-		execResp, err := api.newPayload(*payload, []common.Hash{}, h)
+		execResp, err := api.newPayload(*payload, []common.Hash{}, h, false)
 		if err != nil {
 			t.Fatalf("can't execute payload: %v", err)
 		}
@@ -684,7 +684,7 @@ func assembleBlock(api *ConsensusAPI, parentHash common.Hash, params *engine.Pay
 		Withdrawals:  params.Withdrawals,
 		BeaconRoot:   params.BeaconRoot,
 	}
-	payload, err := api.eth.Miner().BuildPayload(args)
+	payload, err := api.eth.Miner().BuildPayload(args, false)
 	if err != nil {
 		return nil, err
 	}
@@ -922,7 +922,7 @@ func TestNewPayloadOnInvalidTerminalBlock(t *testing.T) {
 		Random:       crypto.Keccak256Hash([]byte{byte(1)}),
 		FeeRecipient: parent.Coinbase(),
 	}
-	payload, err := api.eth.Miner().BuildPayload(args)
+	payload, err := api.eth.Miner().BuildPayload(args, false)
 	if err != nil {
 		t.Fatalf("error preparing payload, err=%v", err)
 	}
@@ -1704,6 +1704,108 @@ func TestParentBeaconBlockRoot(t *testing.T) {
 	}
 }
 
+func TestWitnessCreationAndConsumption(t *testing.T) {
+	log.SetDefault(log.NewLogger(log.NewTerminalHandlerWithLevel(colorable.NewColorableStderr(), log.LevelTrace, true)))
+
+	genesis, blocks := generateMergeChain(10, true)
+
+	// Set cancun time to semi-last block + 5 seconds
+	timestamp := blocks[len(blocks)-2].Time() + 5
+	genesis.Config.ShanghaiTime = &timestamp
+	genesis.Config.CancunTime = &timestamp
+
+	n, ethservice := startEthService(t, genesis, blocks[:9])
+	defer n.Close()
+
+	api := NewConsensusAPI(ethservice)
+
+	// Put the 10th block's tx in the pool and produce a new block
+	txs := blocks[9].Transactions()
+
+	ethservice.TxPool().Add(txs, true, true)
+	blockParams := engine.PayloadAttributes{
+		Timestamp:   blocks[8].Time() + 5,
+		Withdrawals: make([]*types.Withdrawal, 0),
+		BeaconRoot:  &common.Hash{42},
+	}
+	fcState := engine.ForkchoiceStateV1{
+		HeadBlockHash:      blocks[8].Hash(),
+		SafeBlockHash:      common.Hash{},
+		FinalizedBlockHash: common.Hash{},
+	}
+	_, err := api.ForkchoiceUpdatedWithWitnessV3(fcState, &blockParams)
+	if err != nil {
+		t.Fatalf("error preparing payload, err=%v", err)
+	}
+	// Give the payload some time to be built
+	time.Sleep(100 * time.Millisecond)
+
+	payloadID := (&miner.BuildPayloadArgs{
+		Parent:       fcState.HeadBlockHash,
+		Timestamp:    blockParams.Timestamp,
+		FeeRecipient: blockParams.SuggestedFeeRecipient,
+		Random:       blockParams.Random,
+		Withdrawals:  blockParams.Withdrawals,
+		BeaconRoot:   blockParams.BeaconRoot,
+		Version:      engine.PayloadV3,
+	}).Id()
+	envelope, err := api.GetPayloadV3(payloadID)
+	if err != nil {
+		t.Fatalf("error getting payload, err=%v", err)
+	}
+	if len(envelope.ExecutionPayload.Transactions) != blocks[9].Transactions().Len() {
+		t.Fatalf("invalid number of transactions %d != %d", len(envelope.ExecutionPayload.Transactions), blocks[9].Transactions().Len())
+	}
+	if envelope.Witness == nil {
+		t.Fatalf("witness missing from payload")
+	}
+	// Test stateless execution of the created witness
+	wantStateRoot := envelope.ExecutionPayload.StateRoot
+	wantReceiptRoot := envelope.ExecutionPayload.ReceiptsRoot
+
+	envelope.ExecutionPayload.StateRoot = common.Hash{}
+	envelope.ExecutionPayload.ReceiptsRoot = common.Hash{}
+
+	res, err := api.ExecuteStatelessPayloadV3(*envelope.ExecutionPayload, []common.Hash{}, &common.Hash{42}, *envelope.Witness)
+	if err != nil {
+		t.Fatalf("error executing stateless payload witness: %v", err)
+	}
+	if res.StateRoot != wantStateRoot {
+		t.Fatalf("stateless state root mismatch: have %v, want %v", res.StateRoot, wantStateRoot)
+	}
+	if res.ReceiptsRoot != wantReceiptRoot {
+		t.Fatalf("stateless receipt root mismatch: have %v, want %v", res.ReceiptsRoot, wantReceiptRoot)
+	}
+	// Test block insertion with witness creation
+	envelope.ExecutionPayload.StateRoot = wantStateRoot
+	envelope.ExecutionPayload.ReceiptsRoot = wantReceiptRoot
+
+	res2, err := api.NewPayloadWithWitnessV3(*envelope.ExecutionPayload, []common.Hash{}, &common.Hash{42})
+	if err != nil {
+		t.Fatalf("error executing stateless payload witness: %v", err)
+	}
+	if res2.Witness == nil {
+		t.Fatalf("witness missing from payload")
+	}
+	// Test stateless execution of the created witness
+	wantStateRoot = envelope.ExecutionPayload.StateRoot
+	wantReceiptRoot = envelope.ExecutionPayload.ReceiptsRoot
+
+	envelope.ExecutionPayload.StateRoot = common.Hash{}
+	envelope.ExecutionPayload.ReceiptsRoot = common.Hash{}
+
+	res, err = api.ExecuteStatelessPayloadV3(*envelope.ExecutionPayload, []common.Hash{}, &common.Hash{42}, *res2.Witness)
+	if err != nil {
+		t.Fatalf("error executing stateless payload witness: %v", err)
+	}
+	if res.StateRoot != wantStateRoot {
+		t.Fatalf("stateless state root mismatch: have %v, want %v", res.StateRoot, wantStateRoot)
+	}
+	if res.ReceiptsRoot != wantReceiptRoot {
+		t.Fatalf("stateless receipt root mismatch: have %v, want %v", res.ReceiptsRoot, wantReceiptRoot)
+	}
+}
+
 // TestGetClientVersion verifies the expected version info is returned.
 func TestGetClientVersion(t *testing.T) {
 	genesis, preMergeBlocks := generateMergeChain(10, false)

eth/catalyst/simulated_beacon.go

@@ -181,7 +181,7 @@ func (c *SimulatedBeacon) sealBlock(withdrawals []*types.Withdrawal, timestamp u
 		Withdrawals:           withdrawals,
 		Random:                random,
 		BeaconRoot:            &common.Hash{},
-	}, engine.PayloadV3)
+	}, engine.PayloadV3, false)
 	if err != nil {
 		return err
 	}

eth/ethconfig/config.go

@@ -134,9 +134,6 @@ type Config struct {
 	// Enables tracking of SHA3 preimages in the VM
 	EnablePreimageRecording bool
 
-	// Enables prefetching trie nodes for read operations too
-	EnableWitnessCollection bool `toml:"-"`
-
 	// Enables VM tracing
 	VMTrace           string
 	VMTraceJsonConfig string

eth/ethconfig/gen_config.go

@@ -44,7 +44,6 @@ func (c Config) MarshalTOML() (interface{}, error) {
 		BlobPool                blobpool.Config
 		GPO                     gasprice.Config
 		EnablePreimageRecording bool
-		EnableWitnessCollection bool `toml:"-"`
 		VMTrace                 string
 		VMTraceJsonConfig       string
 		DocRoot                 string `toml:"-"`
@@ -82,7 +81,6 @@ func (c Config) MarshalTOML() (interface{}, error) {
 	enc.BlobPool = c.BlobPool
 	enc.GPO = c.GPO
 	enc.EnablePreimageRecording = c.EnablePreimageRecording
-	enc.EnableWitnessCollection = c.EnableWitnessCollection
 	enc.VMTrace = c.VMTrace
 	enc.VMTraceJsonConfig = c.VMTraceJsonConfig
 	enc.DocRoot = c.DocRoot
@@ -124,7 +122,6 @@ func (c *Config) UnmarshalTOML(unmarshal func(interface{}) error) error {
 		BlobPool                *blobpool.Config
 		GPO                     *gasprice.Config
 		EnablePreimageRecording *bool
-		EnableWitnessCollection *bool `toml:"-"`
 		VMTrace                 *string
 		VMTraceJsonConfig       *string
 		DocRoot                 *string `toml:"-"`
@@ -219,9 +216,6 @@ func (c *Config) UnmarshalTOML(unmarshal func(interface{}) error) error {
 	if dec.EnablePreimageRecording != nil {
 		c.EnablePreimageRecording = *dec.EnablePreimageRecording
 	}
-	if dec.EnableWitnessCollection != nil {
-		c.EnableWitnessCollection = *dec.EnableWitnessCollection
-	}
 	if dec.VMTrace != nil {
 		c.VMTrace = *dec.VMTrace
 	}

miner/miner.go

@@ -126,8 +126,8 @@ func (miner *Miner) SetGasTip(tip *big.Int) error {
 }
 
 // BuildPayload builds the payload according to the provided parameters.
-func (miner *Miner) BuildPayload(args *BuildPayloadArgs) (*Payload, error) {
-	return miner.buildPayload(args)
+func (miner *Miner) BuildPayload(args *BuildPayloadArgs, witness bool) (*Payload, error) {
+	return miner.buildPayload(args, witness)
 }
 
 // getPending retrieves the pending block based on the current head block.
@@ -156,7 +156,7 @@ func (miner *Miner) getPending() *newPayloadResult {
 		withdrawals: withdrawal,
 		beaconRoot:  nil,
 		noTxs:       false,
-	})
+	}, false) // we will never make a witness for a pending block
 	if ret.err != nil {
 		return nil
 	}

miner/payload_building.go

@@ -25,6 +25,8 @@ import (
 
 	"github.com/ethereum/go-ethereum/beacon/engine"
 	"github.com/ethereum/go-ethereum/common"
+	"github.com/ethereum/go-ethereum/common/hexutil"
+	"github.com/ethereum/go-ethereum/core/stateless"
 	"github.com/ethereum/go-ethereum/core/types"
 	"github.com/ethereum/go-ethereum/log"
 	"github.com/ethereum/go-ethereum/params"
@@ -69,7 +71,9 @@ func (args *BuildPayloadArgs) Id() engine.PayloadID {
 type Payload struct {
 	id           engine.PayloadID
 	empty        *types.Block
+	emptyWitness *stateless.Witness
 	full         *types.Block
+	fullWitness  *stateless.Witness
 	sidecars     []*types.BlobTxSidecar
 	fullFees     *big.Int
 	stop         chan struct{}
@@ -78,10 +82,11 @@ type Payload struct {
 }
 
 // newPayload initializes the payload object.
-func newPayload(empty *types.Block, id engine.PayloadID) *Payload {
+func newPayload(empty *types.Block, witness *stateless.Witness, id engine.PayloadID) *Payload {
 	payload := &Payload{
 		id:           id,
 		empty:        empty,
+		emptyWitness: witness,
 		stop:         make(chan struct{}),
 	}
 	log.Info("Starting work on payload", "id", payload.id)
@@ -106,6 +111,7 @@ func (payload *Payload) update(r *newPayloadResult, elapsed time.Duration) {
 		payload.full = r.block
 		payload.fullFees = r.fees
 		payload.sidecars = r.sidecars
+		payload.fullWitness = r.witness
 
 		feesInEther := new(big.Float).Quo(new(big.Float).SetInt(r.fees), big.NewFloat(params.Ether))
 		log.Info("Updated payload",
@@ -135,9 +141,19 @@ func (payload *Payload) Resolve() *engine.ExecutionPayloadEnvelope {
 		close(payload.stop)
 	}
 	if payload.full != nil {
-		return engine.BlockToExecutableData(payload.full, payload.fullFees, payload.sidecars)
+		envelope := engine.BlockToExecutableData(payload.full, payload.fullFees, payload.sidecars)
+		if payload.fullWitness != nil {
+			envelope.Witness = new(hexutil.Bytes)
+			*envelope.Witness, _ = rlp.EncodeToBytes(payload.fullWitness) // cannot fail
 		}
-	return engine.BlockToExecutableData(payload.empty, big.NewInt(0), nil)
+		return envelope
+	}
+	envelope := engine.BlockToExecutableData(payload.empty, big.NewInt(0), nil)
+	if payload.emptyWitness != nil {
+		envelope.Witness = new(hexutil.Bytes)
+		*envelope.Witness, _ = rlp.EncodeToBytes(payload.emptyWitness) // cannot fail
+	}
+	return envelope
 }
 
 // ResolveEmpty is basically identical to Resolve, but it expects empty block only.
@@ -146,7 +162,12 @@ func (payload *Payload) ResolveEmpty() *engine.ExecutionPayloadEnvelope {
 	payload.lock.Lock()
 	defer payload.lock.Unlock()
 
-	return engine.BlockToExecutableData(payload.empty, big.NewInt(0), nil)
+	envelope := engine.BlockToExecutableData(payload.empty, big.NewInt(0), nil)
+	if payload.emptyWitness != nil {
+		envelope.Witness = new(hexutil.Bytes)
+		*envelope.Witness, _ = rlp.EncodeToBytes(payload.emptyWitness) // cannot fail
+	}
+	return envelope
 }
 
 // ResolveFull is basically identical to Resolve, but it expects full block only.
@@ -172,11 +193,16 @@ func (payload *Payload) ResolveFull() *engine.ExecutionPayloadEnvelope {
 	default:
 		close(payload.stop)
 	}
-	return engine.BlockToExecutableData(payload.full, payload.fullFees, payload.sidecars)
+	envelope := engine.BlockToExecutableData(payload.full, payload.fullFees, payload.sidecars)
+	if payload.fullWitness != nil {
+		envelope.Witness = new(hexutil.Bytes)
+		*envelope.Witness, _ = rlp.EncodeToBytes(payload.fullWitness) // cannot fail
+	}
+	return envelope
 }
 
 // buildPayload builds the payload according to the provided parameters.
-func (miner *Miner) buildPayload(args *BuildPayloadArgs) (*Payload, error) {
+func (miner *Miner) buildPayload(args *BuildPayloadArgs, witness bool) (*Payload, error) {
 	// Build the initial version with no transaction included. It should be fast
 	// enough to run. The empty payload can at least make sure there is something
 	// to deliver for not missing slot.
@@ -190,13 +216,12 @@ func (miner *Miner) buildPayload(args *BuildPayloadArgs) (*Payload, error) {
 		beaconRoot:  args.BeaconRoot,
 		noTxs:       true,
 	}
-	empty := miner.generateWork(emptyParams)
+	empty := miner.generateWork(emptyParams, witness)
 	if empty.err != nil {
 		return nil, empty.err
 	}
-
 	// Construct a payload object for return.
-	payload := newPayload(empty.block, args.Id())
+	payload := newPayload(empty.block, empty.witness, args.Id())
 
 	// Spin up a routine for updating the payload in background. This strategy
 	// can maximum the revenue for including transactions with highest fee.
@@ -226,7 +251,7 @@ func (miner *Miner) buildPayload(args *BuildPayloadArgs) (*Payload, error) {
 			select {
 			case <-timer.C:
 				start := time.Now()
-				r := miner.generateWork(fullParams)
+				r := miner.generateWork(fullParams, witness)
 				if r.err == nil {
 					payload.update(r, time.Since(start))
 				} else {

miner/payload_building_test.go

@@ -160,7 +160,7 @@ func TestBuildPayload(t *testing.T) {
 		Random:       common.Hash{},
 		FeeRecipient: recipient,
 	}
-	payload, err := w.buildPayload(args)
+	payload, err := w.buildPayload(args, false)
 	if err != nil {
 		t.Fatalf("Failed to build payload %v", err)
 	}

miner/worker.go

@@ -28,6 +28,7 @@ import (
 	"github.com/ethereum/go-ethereum/consensus/misc/eip4844"
 	"github.com/ethereum/go-ethereum/core"
 	"github.com/ethereum/go-ethereum/core/state"
+	"github.com/ethereum/go-ethereum/core/stateless"
 	"github.com/ethereum/go-ethereum/core/txpool"
 	"github.com/ethereum/go-ethereum/core/types"
 	"github.com/ethereum/go-ethereum/core/vm"
@@ -56,6 +57,8 @@ type environment struct {
 	receipts []*types.Receipt
 	sidecars []*types.BlobTxSidecar
 	blobs    int
+
+	witness *stateless.Witness
 }
 
 const (
@@ -73,6 +76,7 @@ type newPayloadResult struct {
 	sidecars []*types.BlobTxSidecar // collected blobs of blob transactions
 	stateDB  *state.StateDB         // StateDB after executing the transactions
 	receipts []*types.Receipt       // Receipts collected during construction
+	witness  *stateless.Witness     // Witness is an optional stateless proof
 }
 
 // generateParams wraps various settings for generating sealing task.
@@ -88,8 +92,8 @@ type generateParams struct {
 }
 
 // generateWork generates a sealing block based on the given parameters.
-func (miner *Miner) generateWork(params *generateParams) *newPayloadResult {
-	work, err := miner.prepareWork(params)
+func (miner *Miner) generateWork(params *generateParams, witness bool) *newPayloadResult {
+	work, err := miner.prepareWork(params, witness)
 	if err != nil {
 		return &newPayloadResult{err: err}
 	}
@@ -129,13 +133,14 @@ func (miner *Miner) generateWork(params *generateParams) *newPayloadResult {
 		sidecars: work.sidecars,
 		stateDB:  work.state,
 		receipts: work.receipts,
+		witness:  work.witness,
 	}
 }
 
 // prepareWork constructs the sealing task according to the given parameters,
 // either based on the last chain head or specified parent. In this function
 // the pending transactions are not filled yet, only the empty task returned.
-func (miner *Miner) prepareWork(genParams *generateParams) (*environment, error) {
+func (miner *Miner) prepareWork(genParams *generateParams, witness bool) (*environment, error) {
 	miner.confMu.RLock()
 	defer miner.confMu.RUnlock()
 
@@ -203,7 +208,7 @@ func (miner *Miner) prepareWork(genParams *generateParams) (*environment, error)
 	// Could potentially happen if starting to mine in an odd state.
 	// Note genParams.coinbase can be different with header.Coinbase
 	// since clique algorithm can modify the coinbase field in header.
-	env, err := miner.makeEnv(parent, header, genParams.coinbase)
+	env, err := miner.makeEnv(parent, header, genParams.coinbase, witness)
 	if err != nil {
 		log.Error("Failed to create sealing context", "err", err)
 		return nil, err
@@ -222,18 +227,26 @@ func (miner *Miner) prepareWork(genParams *generateParams) (*environment, error)
 }
 
 // makeEnv creates a new environment for the sealing block.
-func (miner *Miner) makeEnv(parent *types.Header, header *types.Header, coinbase common.Address) (*environment, error) {
+func (miner *Miner) makeEnv(parent *types.Header, header *types.Header, coinbase common.Address, witness bool) (*environment, error) {
 	// Retrieve the parent state to execute on top.
 	state, err := miner.chain.StateAt(parent.Root)
 	if err != nil {
 		return nil, err
 	}
+	if witness {
+		bundle, err := stateless.NewWitness(header, miner.chain)
+		if err != nil {
+			return nil, err
+		}
+		state.StartPrefetcher("miner", bundle)
+	}
 	// Note the passed coinbase may be different with header.Coinbase.
 	return &environment{
 		signer:   types.MakeSigner(miner.chainConfig, header.Number, header.Time),
 		state:    state,
 		coinbase: coinbase,
 		header:   header,
+		witness:  state.Witness(),
 	}, nil
 }
 

tests/block_test_util.go

@@ -152,7 +152,7 @@ func (t *BlockTest) Run(snapshotter bool, scheme string, witness bool, tracer *t
 	}
 	chain, err := core.NewBlockChain(db, cache, gspec, nil, engine, vm.Config{
 		Tracer:                  tracer,
-		EnableWitnessCollection: witness,
+		StatelessSelfValidation: witness,
 	}, nil)
 	if err != nil {
 		return err