mevexec: callbundle

core/chain_makers.go

@@ -103,7 +103,7 @@ func (b *BlockGen) AddTxWithChain(bc *BlockChain, tx *types.Transaction) {
 		b.SetCoinbase(common.Address{})
 	}
 	b.statedb.Prepare(tx.Hash(), len(b.txs))
-	receipt, err := ApplyTransaction(b.config, bc, &b.header.Coinbase, b.gasPool, b.statedb, b.header, tx, &b.header.GasUsed, vm.Config{})
+	receipt, _, err := ApplyTransaction(b.config, bc, &b.header.Coinbase, b.gasPool, b.statedb, b.header, tx, &b.header.GasUsed, vm.Config{})
 	if err != nil {
 		panic(err)
 	}

core/state_processor.go

@@ -79,7 +79,7 @@ func (p *StateProcessor) Process(block *types.Block, statedb *state.StateDB, cfg
 			return nil, nil, 0, fmt.Errorf("could not apply tx %d [%v]: %w", i, tx.Hash().Hex(), err)
 		}
 		statedb.Prepare(tx.Hash(), i)
-		receipt, err := applyTransaction(msg, p.config, nil, gp, statedb, blockNumber, blockHash, tx, usedGas, vmenv)
+		receipt, _, err := applyTransaction(msg, p.config, nil, gp, statedb, blockNumber, blockHash, tx, usedGas, vmenv)
 		if err != nil {
 			return nil, nil, 0, fmt.Errorf("could not apply tx %d [%v]: %w", i, tx.Hash().Hex(), err)
 		}
@@ -92,15 +92,15 @@ func (p *StateProcessor) Process(block *types.Block, statedb *state.StateDB, cfg
 	return receipts, allLogs, *usedGas, nil
 }
 
-func applyTransaction(msg types.Message, config *params.ChainConfig, author *common.Address, gp *GasPool, statedb *state.StateDB, blockNumber *big.Int, blockHash common.Hash, tx *types.Transaction, usedGas *uint64, evm *vm.EVM) (*types.Receipt, error) {
+func applyTransaction(msg types.Message, config *params.ChainConfig, author *common.Address, gp *GasPool, statedb *state.StateDB, blockNumber *big.Int, blockHash common.Hash, tx *types.Transaction, usedGas *uint64, evm *vm.EVM) (*types.Receipt, *ExecutionResult, error) {
 	// Create a new context to be used in the EVM environment.
 	txContext := NewEVMTxContext(msg)
 	evm.Reset(txContext, statedb)
 
 	// Apply the transaction to the current state (included in the env).
 	result, err := ApplyMessage(evm, msg, gp)
 	if err != nil {
-		return nil, err
+		return nil, nil, err
 	}
 
 	// Update the state with pending changes.
@@ -134,17 +134,18 @@ func applyTransaction(msg types.Message, config *params.ChainConfig, author *com
 	receipt.BlockHash = blockHash
 	receipt.BlockNumber = blockNumber
 	receipt.TransactionIndex = uint(statedb.TxIndex())
-	return receipt, err
+	return receipt, result, err
 }
 
 // ApplyTransaction attempts to apply a transaction to the given state database
 // and uses the input parameters for its environment. It returns the receipt
 // for the transaction, gas used and an error if the transaction failed,
 // indicating the block was invalid.
-func ApplyTransaction(config *params.ChainConfig, bc ChainContext, author *common.Address, gp *GasPool, statedb *state.StateDB, header *types.Header, tx *types.Transaction, usedGas *uint64, cfg vm.Config) (*types.Receipt, error) {
+// mevexec: additionally returns the full result, which can be should at a later stage where unneccessary
+func ApplyTransaction(config *params.ChainConfig, bc ChainContext, author *common.Address, gp *GasPool, statedb *state.StateDB, header *types.Header, tx *types.Transaction, usedGas *uint64, cfg vm.Config) (*types.Receipt, *ExecutionResult, error) {
 	msg, err := tx.AsMessage(types.MakeSigner(config, header.Number), header.BaseFee)
 	if err != nil {
-		return nil, err
+		return nil, nil, err
 	}
 	// Create a new context to be used in the EVM environment
 	blockContext := NewEVMBlockContext(header, bc, author)

eth/backend.go

@@ -290,7 +290,7 @@ func makeExtraData(extra []byte) []byte {
 // APIs return the collection of RPC services the ethereum package offers.
 // NOTE, some of these services probably need to be moved to somewhere else.
 func (s *Ethereum) APIs() []rpc.API {
-	apis := ethapi.GetAPIs(s.APIBackend)
+	apis := ethapi.GetAPIs(s.APIBackend, s.blockchain)
 
 	// Append any APIs exposed explicitly by the consensus engine
 	apis = append(apis, s.engine.APIs(s.BlockChain())...)

internal/ethapi/api.go

@@ -18,6 +18,7 @@ package ethapi
 
 import (
 	"context"
+	"encoding/hex"
 	"errors"
 	"fmt"
 	"math/big"
@@ -46,6 +47,7 @@ import (
 	"github.com/ethereum/go-ethereum/rlp"
 	"github.com/ethereum/go-ethereum/rpc"
 	"github.com/tyler-smith/go-bip39"
+	"golang.org/x/crypto/sha3"
 )
 
 // EthereumAPI provides an API to access Ethereum related information.
@@ -1449,6 +1451,74 @@ func AccessList(ctx context.Context, b Backend, blockNrOrHash rpc.BlockNumberOrH
 	}
 }
 
+// Creates an access list on top of given state
+// identical to AccessList, with the exception of state is loaded in arguments
+func AccessListOnState(ctx context.Context, b Backend, header *types.Header, db *state.StateDB, args TransactionArgs) (acl types.AccessList, gasUsed uint64, vmErr error, err error) {
+	// If the gas amount is not set, extract this as it will depend on access
+	// lists and we'll need to reestimate every time
+	nogas := args.Gas == nil
+
+	// Ensure any missing fields are filled, extract the recipient and input data
+	if err := args.setDefaults(ctx, b); err != nil {
+		return nil, 0, nil, err
+	}
+	var to common.Address
+	if args.To != nil {
+		to = *args.To
+	} else {
+		to = crypto.CreateAddress(args.from(), uint64(*args.Nonce))
+	}
+	// Retrieve the precompiles since they don't need to be added to the access list
+	isPostMerge := header.Difficulty.Cmp(common.Big0) == 0
+	// Retrieve the precompiles since they don't need to be added to the access list
+	precompiles := vm.ActivePrecompiles(b.ChainConfig().Rules(header.Number, isPostMerge))
+
+	// Create an initial tracer
+	prevTracer := logger.NewAccessListTracer(nil, args.from(), to, precompiles)
+	if args.AccessList != nil {
+		prevTracer = logger.NewAccessListTracer(*args.AccessList, args.from(), to, precompiles)
+	}
+	for {
+		// Retrieve the current access list to expand
+		accessList := prevTracer.AccessList()
+		log.Trace("Creating access list", "input", accessList)
+
+		// If no gas amount was specified, each unique access list needs it's own
+		// gas calculation. This is quite expensive, but we need to be accurate
+		// and it's convered by the sender only anyway.
+		if nogas {
+			args.Gas = nil
+			if err := args.setDefaults(ctx, b); err != nil {
+				return nil, 0, nil, err // shouldn't happen, just in case
+			}
+		}
+
+		statedb := db.Copy() // woops shouldn't have removed this lol
+		// Set the accesslist to the last al
+		args.AccessList = &accessList
+		msg, err := args.ToMessage(b.RPCGasCap(), header.BaseFee)
+		if err != nil {
+			return nil, 0, nil, err
+		}
+
+		// Apply the transaction with the access list tracer
+		tracer := logger.NewAccessListTracer(accessList, args.from(), to, precompiles)
+		config := vm.Config{Tracer: tracer, Debug: true, NoBaseFee: true}
+		vmenv, _, err := b.GetEVM(ctx, msg, statedb, header, &config)
+		if err != nil {
+			return nil, 0, nil, err
+		}
+		res, err := core.ApplyMessage(vmenv, msg, new(core.GasPool).AddGas(msg.Gas()))
+		if err != nil {
+			return nil, 0, nil, fmt.Errorf("failed to apply transaction: %v err: %v", args.toTransaction().Hash(), err)
+		}
+		if tracer.Equal(prevTracer) {
+			return accessList, res.UsedGas, res.Err, nil
+		}
+		prevTracer = tracer
+	}
+}
+
 // TransactionAPI exposes methods for reading and creating transaction data.
 type TransactionAPI struct {
 	b         Backend
@@ -2064,3 +2134,236 @@ func toHexSlice(b [][]byte) []string {
 	}
 	return r
 }
+
+// MEVEXEC ADDITIONS
+// the following are additional rpc methods added into the execution client for mev searchers
+
+// BlockChainAPI provides an API to access Ethereum blockchain data.
+type SearcherAPI struct {
+	b     Backend
+	chain *core.BlockChain
+}
+
+func NewSearcherAPI(b Backend, chain *core.BlockChain) *SearcherAPI {
+	return &SearcherAPI{b, chain}
+}
+
+// CallBundleArgs represents the arguments for a call.
+type CallBundleArgs struct {
+	Txs                    []hexutil.Bytes       `json:"txs"`
+	BlockNumber            rpc.BlockNumber       `json:"blockNumber"`
+	StateBlockNumberOrHash rpc.BlockNumberOrHash `json:"stateBlockNumber"`
+	Coinbase               *string               `json:"coinbase"`
+	Timestamp              *uint64               `json:"timestamp"`
+	Timeout                *int64                `json:"timeout"`
+	GasLimit               *uint64               `json:"gasLimit"`
+	Difficulty             *big.Int              `json:"difficulty"`
+	BaseFee                *big.Int              `json:"baseFee"`
+	SimulationLogs         bool                  `json:"simulationLogs"`
+	CreateAccessList       bool                  `json:"createAccessList"`
+	StateOverrides         *StateOverride        `json:"stateOverrides"`
+}
+
+// CallBundle will simulate a bundle of transactions at the top of a given block
+// number with the state of another (or the same) block. This can be used to
+// simulate future blocks with the current state, or it can be used to simulate
+// a past block.
+// The sender is responsible for signing the transactions and using the correct
+// nonce and ensuring validity
+func (s *SearcherAPI) CallBundle(ctx context.Context, args CallBundleArgs) (map[string]interface{}, error) {
+	if len(args.Txs) == 0 {
+		return nil, errors.New("bundle missing txs")
+	}
+	if args.BlockNumber == 0 {
+		return nil, errors.New("bundle missing blockNumber")
+	}
+
+	var txs types.Transactions
+
+	for _, encodedTx := range args.Txs {
+		tx := new(types.Transaction)
+		if err := tx.UnmarshalBinary(encodedTx); err != nil {
+			return nil, err
+		}
+		txs = append(txs, tx)
+	}
+	defer func(start time.Time) { log.Debug("Executing EVM call finished", "runtime", time.Since(start)) }(time.Now())
+
+	timeoutMilliSeconds := int64(5000)
+	if args.Timeout != nil {
+		timeoutMilliSeconds = *args.Timeout
+	}
+	timeout := time.Millisecond * time.Duration(timeoutMilliSeconds)
+	state, parent, err := s.b.StateAndHeaderByNumberOrHash(ctx, args.StateBlockNumberOrHash)
+	if state == nil || err != nil {
+		return nil, err
+	}
+	if err := args.StateOverrides.Apply(state); err != nil {
+		return nil, err
+	}
+	blockNumber := big.NewInt(int64(args.BlockNumber))
+
+	timestamp := parent.Time + 1
+	if args.Timestamp != nil {
+		timestamp = *args.Timestamp
+	}
+	coinbase := parent.Coinbase
+	if args.Coinbase != nil {
+		coinbase = common.HexToAddress(*args.Coinbase)
+	}
+	difficulty := parent.Difficulty
+	if args.Difficulty != nil {
+		difficulty = args.Difficulty
+	}
+	gasLimit := parent.GasLimit
+	if args.GasLimit != nil {
+		gasLimit = *args.GasLimit
+	}
+	var baseFee *big.Int
+	if args.BaseFee != nil {
+		baseFee = args.BaseFee
+	} else if s.b.ChainConfig().IsLondon(big.NewInt(args.BlockNumber.Int64())) {
+		baseFee = misc.CalcBaseFee(s.b.ChainConfig(), parent)
+	}
+	header := &types.Header{
+		ParentHash: parent.Hash(),
+		Number:     blockNumber,
+		GasLimit:   gasLimit,
+		Time:       timestamp,
+		Difficulty: difficulty,
+		Coinbase:   coinbase,
+		BaseFee:    baseFee,
+	}
+
+	// Setup context so it may be cancelled the call has completed
+	// or, in case of unmetered gas, setup a context with a timeout.
+	var cancel context.CancelFunc
+	if timeout > 0 {
+		ctx, cancel = context.WithTimeout(ctx, timeout)
+	} else {
+		ctx, cancel = context.WithCancel(ctx)
+	}
+	// Make sure the context is cancelled when the call has completed
+	// this makes sure resources are cleaned up.
+	defer cancel()
+
+	vmconfig := vm.Config{}
+
+	// Setup the gas pool (also for unmetered requests)
+	// and apply the message.
+	gp := new(core.GasPool).AddGas(math.MaxUint64)
+
+	results := []map[string]interface{}{}
+	coinbaseBalanceBefore := state.GetBalance(coinbase)
+
+	bundleHash := sha3.NewLegacyKeccak256()
+	signer := types.MakeSigner(s.b.ChainConfig(), blockNumber)
+	var totalGasUsed uint64
+	gasFees := new(big.Int)
+	for i, tx := range txs {
+		coinbaseBalanceBeforeTx := state.GetBalance(coinbase)
+		state.Prepare(tx.Hash(), i)
+
+		accessListState := state.Copy() // create a copy just in case we use it later for access list creation
+
+		receipt, result, err := core.ApplyTransaction(s.b.ChainConfig(), s.chain, &coinbase, gp, state, header, tx, &header.GasUsed, vmconfig)
+		if err != nil {
+			return nil, fmt.Errorf("err: %w; txhash %s", err, tx.Hash())
+		}
+
+		txHash := tx.Hash().String()
+		from, err := types.Sender(signer, tx)
+		if err != nil {
+			return nil, fmt.Errorf("err: %w; txhash %s", err, tx.Hash())
+		}
+		to := "0x"
+		if tx.To() != nil {
+			to = tx.To().String()
+		}
+		jsonResult := map[string]interface{}{
+			"txHash":      txHash,
+			"gasUsed":     receipt.GasUsed,
+			"fromAddress": from.String(),
+			"toAddress":   to,
+		}
+		totalGasUsed += receipt.GasUsed
+		gasPrice, err := tx.EffectiveGasTip(header.BaseFee)
+		if err != nil {
+			return nil, fmt.Errorf("err: %w; txhash %s", err, tx.Hash())
+		}
+		gasFeesTx := new(big.Int).Mul(big.NewInt(int64(receipt.GasUsed)), gasPrice)
+		gasFees.Add(gasFees, gasFeesTx)
+		bundleHash.Write(tx.Hash().Bytes())
+		if result.Err != nil {
+			jsonResult["error"] = result.Err.Error()
+			revert := result.Revert()
+			if len(revert) > 0 {
+				jsonResult["revert"] = string(revert)
+			}
+		} else {
+			dst := make([]byte, hex.EncodedLen(len(result.Return())))
+			hex.Encode(dst, result.Return())
+			jsonResult["value"] = "0x" + string(dst)
+		}
+		// if simulation logs are requested append it to logs
+		if args.SimulationLogs {
+			jsonResult["logs"] = receipt.Logs
+		}
+		// if an access list is requested create and append
+		if args.CreateAccessList {
+			// ifdk another way to fill all values so this will have to do - x2
+			txArgGas := hexutil.Uint64(tx.Gas())
+			txArgNonce := hexutil.Uint64(tx.Nonce())
+			txArgData := hexutil.Bytes(tx.Data())
+			txargs := TransactionArgs{
+				From:    &from,
+				To:      tx.To(),
+				Gas:     &txArgGas,
+				Nonce:   &txArgNonce,
+				Data:    &txArgData,
+				Value:   (*hexutil.Big)(tx.Value()),
+				ChainID: (*hexutil.Big)(tx.ChainId()),
+			}
+			if tx.GasFeeCap().Cmp(big.NewInt(0)) == 0 { // no maxbasefee, set gasprice instead
+				txargs.GasPrice = (*hexutil.Big)(tx.GasPrice())
+			} else { // otherwise set base and priority fee
+				txargs.MaxFeePerGas = (*hexutil.Big)(tx.GasFeeCap())
+				txargs.MaxPriorityFeePerGas = (*hexutil.Big)(tx.GasTipCap())
+			}
+			acl, gasUsed, vmerr, err := AccessListOnState(ctx, s.b, header, accessListState, txargs)
+			if err == nil {
+				if gasUsed != receipt.GasUsed {
+					log.Debug("Gas used in receipt differ from accesslist", "receipt", receipt.GasUsed, "acl", gasUsed) // weird bug but it works
+				}
+				if vmerr != nil {
+					log.Info("CallBundle accesslist creation encountered vmerr", "vmerr", vmerr)
+				}
+				jsonResult["accessList"] = acl
+
+			} else {
+				log.Info("CallBundle accesslist creation encountered err", "err", err)
+				jsonResult["accessList"] = acl //
+			} // return the empty accesslist either way
+		}
+		coinbaseDiffTx := new(big.Int).Sub(state.GetBalance(coinbase), coinbaseBalanceBeforeTx)
+		jsonResult["coinbaseDiff"] = coinbaseDiffTx.String()
+		jsonResult["gasFees"] = gasFeesTx.String()
+		jsonResult["ethSentToCoinbase"] = new(big.Int).Sub(coinbaseDiffTx, gasFeesTx).String()
+		jsonResult["gasPrice"] = new(big.Int).Div(coinbaseDiffTx, big.NewInt(int64(receipt.GasUsed))).String()
+		jsonResult["gasUsed"] = receipt.GasUsed
+		results = append(results, jsonResult)
+	}
+
+	ret := map[string]interface{}{}
+	ret["results"] = results
+	coinbaseDiff := new(big.Int).Sub(state.GetBalance(coinbase), coinbaseBalanceBefore)
+	ret["coinbaseDiff"] = coinbaseDiff.String()
+	ret["gasFees"] = gasFees.String()
+	ret["ethSentToCoinbase"] = new(big.Int).Sub(coinbaseDiff, gasFees).String()
+	ret["bundleGasPrice"] = new(big.Int).Div(coinbaseDiff, big.NewInt(int64(totalGasUsed))).String()
+	ret["totalGasUsed"] = totalGasUsed
+	ret["stateBlockNumber"] = parent.Number.Int64()
+
+	ret["bundleHash"] = "0x" + common.Bytes2Hex(bundleHash.Sum(nil))
+	return ret, nil
+}