internal/ethapi: add block overrides to eth_call (#26414)

Adds an optional config parameter to eth_call which allows users to override block context fields (same functionality that was added to traceCall in #24871)

---------

Co-authored-by: Martin Holst Swende <martin@swende.se>

eth/api_backend.go

@@ -246,12 +246,17 @@ func (b *EthAPIBackend) GetTd(ctx context.Context, hash common.Hash) *big.Int {
 	return nil
 }
 
-func (b *EthAPIBackend) GetEVM(ctx context.Context, msg *core.Message, state *state.StateDB, header *types.Header, vmConfig *vm.Config) (*vm.EVM, func() error, error) {
+func (b *EthAPIBackend) GetEVM(ctx context.Context, msg *core.Message, state *state.StateDB, header *types.Header, vmConfig *vm.Config, blockCtx *vm.BlockContext) (*vm.EVM, func() error, error) {
 	if vmConfig == nil {
 		vmConfig = b.eth.blockchain.GetVMConfig()
 	}
 	txContext := core.NewEVMTxContext(msg)
-	context := core.NewEVMBlockContext(header, b.eth.BlockChain(), nil)
+	var context vm.BlockContext
+	if blockCtx != nil {
+		context = *blockCtx
+	} else {
+		context = core.NewEVMBlockContext(header, b.eth.BlockChain(), nil)
+	}
 	return vm.NewEVM(context, txContext, state, b.eth.blockchain.Config(), *vmConfig), state.Error, nil
 }
 

eth/tracers/api.go

@@ -100,34 +100,10 @@ func NewAPI(backend Backend) *API {
 	return &API{backend: backend}
 }
 
-type chainContext struct {
-	api *API
-	ctx context.Context
-}
-
-func (context *chainContext) Engine() consensus.Engine {
-	return context.api.backend.Engine()
-}
-
-func (context *chainContext) GetHeader(hash common.Hash, number uint64) *types.Header {
-	header, err := context.api.backend.HeaderByNumber(context.ctx, rpc.BlockNumber(number))
-	if err != nil {
-		return nil
-	}
-	if header.Hash() == hash {
-		return header
-	}
-	header, err = context.api.backend.HeaderByHash(context.ctx, hash)
-	if err != nil {
-		return nil
-	}
-	return header
-}
-
 // chainContext constructs the context reader which is used by the evm for reading
 // the necessary chain context.
 func (api *API) chainContext(ctx context.Context) core.ChainContext {
-	return &chainContext{api: api, ctx: ctx}
+	return ethapi.NewChainContext(ctx, api.backend)
 }
 
 // blockByNumber is the wrapper of the chain access function offered by the backend.

ethclient/gethclient/gethclient.go

@@ -143,6 +143,28 @@ func (ec *Client) CallContract(ctx context.Context, msg ethereum.CallMsg, blockN
 	return hex, err
 }
 
+// CallContractWithBlockOverrides executes a message call transaction, which is directly executed
+// in the VM  of the node, but never mined into the blockchain.
+//
+// blockNumber selects the block height at which the call runs. It can be nil, in which
+// case the code is taken from the latest known block. Note that state from very old
+// blocks might not be available.
+//
+// overrides specifies a map of contract states that should be overwritten before executing
+// the message call.
+//
+// blockOverrides specifies block fields exposed to the EVM that can be overridden for the call.
+//
+// Please use ethclient.CallContract instead if you don't need the override functionality.
+func (ec *Client) CallContractWithBlockOverrides(ctx context.Context, msg ethereum.CallMsg, blockNumber *big.Int, overrides *map[common.Address]OverrideAccount, blockOverrides BlockOverrides) ([]byte, error) {
+	var hex hexutil.Bytes
+	err := ec.c.CallContext(
+		ctx, &hex, "eth_call", toCallArg(msg),
+		toBlockNumArg(blockNumber), overrides, blockOverrides,
+	)
+	return hex, err
+}
+
 // GCStats retrieves the current garbage collection stats from a geth node.
 func (ec *Client) GCStats(ctx context.Context) (*debug.GCStats, error) {
 	var result debug.GCStats
@@ -265,3 +287,52 @@ func (a OverrideAccount) MarshalJSON() ([]byte, error) {
 	}
 	return json.Marshal(output)
 }
+
+// BlockOverrides specifies the  set of header fields to override.
+type BlockOverrides struct {
+	// Number overrides the block number.
+	Number *big.Int
+	// Difficulty overrides the block difficulty.
+	Difficulty *big.Int
+	// Time overrides the block timestamp. Time is applied only when
+	// it is non-zero.
+	Time uint64
+	// GasLimit overrides the block gas limit. GasLimit is applied only when
+	// it is non-zero.
+	GasLimit uint64
+	// Coinbase overrides the block coinbase. Coinbase is applied only when
+	// it is different from the zero address.
+	Coinbase common.Address
+	// Random overrides the block extra data which feeds into the RANDOM opcode.
+	// Random is applied only when it is a non-zero hash.
+	Random common.Hash
+	// BaseFee overrides the block base fee.
+	BaseFee *big.Int
+}
+
+func (o BlockOverrides) MarshalJSON() ([]byte, error) {
+	type override struct {
+		Number     *hexutil.Big    `json:"number,omitempty"`
+		Difficulty *hexutil.Big    `json:"difficulty,omitempty"`
+		Time       hexutil.Uint64  `json:"time,omitempty"`
+		GasLimit   hexutil.Uint64  `json:"gasLimit,omitempty"`
+		Coinbase   *common.Address `json:"coinbase,omitempty"`
+		Random     *common.Hash    `json:"random,omitempty"`
+		BaseFee    *hexutil.Big    `json:"baseFee,omitempty"`
+	}
+
+	output := override{
+		Number:     (*hexutil.Big)(o.Number),
+		Difficulty: (*hexutil.Big)(o.Difficulty),
+		Time:       hexutil.Uint64(o.Time),
+		GasLimit:   hexutil.Uint64(o.GasLimit),
+		BaseFee:    (*hexutil.Big)(o.BaseFee),
+	}
+	if o.Coinbase != (common.Address{}) {
+		output.Coinbase = &o.Coinbase
+	}
+	if o.Random != (common.Hash{}) {
+		output.Random = &o.Random
+	}
+	return json.Marshal(output)
+}

ethclient/gethclient/gethclient_test.go

@@ -127,6 +127,9 @@ func TestGethClient(t *testing.T) {
 		}, {
 			"TestCallContract",
 			func(t *testing.T) { testCallContract(t, client) },
+		}, {
+			"TestCallContractWithBlockOverrides",
+			func(t *testing.T) { testCallContractWithBlockOverrides(t, client) },
 		},
 		// The testaccesslist is a bit time-sensitive: the newTestBackend imports
 		// one block. The `testAcessList` fails if the miner has not yet created a
@@ -413,3 +416,75 @@ func TestOverrideAccountMarshal(t *testing.T) {
 		t.Error("want:", expected)
 	}
 }
+
+func TestBlockOverridesMarshal(t *testing.T) {
+	for i, tt := range []struct {
+		bo   BlockOverrides
+		want string
+	}{
+		{
+			bo:   BlockOverrides{},
+			want: `{}`,
+		},
+		{
+			bo: BlockOverrides{
+				Coinbase: common.HexToAddress("0x1111111111111111111111111111111111111111"),
+			},
+			want: `{"coinbase":"0x1111111111111111111111111111111111111111"}`,
+		},
+		{
+			bo: BlockOverrides{
+				Number:     big.NewInt(1),
+				Difficulty: big.NewInt(2),
+				Time:       3,
+				GasLimit:   4,
+				BaseFee:    big.NewInt(5),
+			},
+			want: `{"number":"0x1","difficulty":"0x2","time":"0x3","gasLimit":"0x4","baseFee":"0x5"}`,
+		},
+	} {
+		marshalled, err := json.Marshal(&tt.bo)
+		if err != nil {
+			t.Fatalf("unexpected error: %v", err)
+		}
+		if string(marshalled) != tt.want {
+			t.Errorf("Testcase #%d failed. expected\n%s\ngot\n%s", i, tt.want, string(marshalled))
+		}
+	}
+}
+
+func testCallContractWithBlockOverrides(t *testing.T, client *rpc.Client) {
+	ec := New(client)
+	msg := ethereum.CallMsg{
+		From:     testAddr,
+		To:       &common.Address{},
+		Gas:      50000,
+		GasPrice: big.NewInt(1000000000),
+		Value:    big.NewInt(1),
+	}
+	override := OverrideAccount{
+		// Returns coinbase address.
+		Code: common.FromHex("0x41806000526014600cf3"),
+	}
+	mapAcc := make(map[common.Address]OverrideAccount)
+	mapAcc[common.Address{}] = override
+	res, err := ec.CallContract(context.Background(), msg, big.NewInt(0), &mapAcc)
+	if err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+	if !bytes.Equal(res, common.FromHex("0x0000000000000000000000000000000000000000")) {
+		t.Fatalf("unexpected result: %x", res)
+	}
+
+	// Now test with block overrides
+	bo := BlockOverrides{
+		Coinbase: common.HexToAddress("0x1111111111111111111111111111111111111111"),
+	}
+	res, err = ec.CallContractWithBlockOverrides(context.Background(), msg, big.NewInt(0), &mapAcc, bo)
+	if err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+	if !bytes.Equal(res, common.FromHex("0x1111111111111111111111111111111111111111")) {
+		t.Fatalf("unexpected result: %x", res)
+	}
+}

graphql/graphql.go

@@ -1068,7 +1068,7 @@ func (c *CallResult) Status() hexutil.Uint64 {
 func (b *Block) Call(ctx context.Context, args struct {
 	Data ethapi.TransactionArgs
 }) (*CallResult, error) {
-	result, err := ethapi.DoCall(ctx, b.r.backend, args.Data, *b.numberOrHash, nil, b.r.backend.RPCEVMTimeout(), b.r.backend.RPCGasCap())
+	result, err := ethapi.DoCall(ctx, b.r.backend, args.Data, *b.numberOrHash, nil, nil, b.r.backend.RPCEVMTimeout(), b.r.backend.RPCGasCap())
 	if err != nil {
 		return nil, err
 	}
@@ -1131,7 +1131,7 @@ func (p *Pending) Call(ctx context.Context, args struct {
 	Data ethapi.TransactionArgs
 }) (*CallResult, error) {
 	pendingBlockNr := rpc.BlockNumberOrHashWithNumber(rpc.PendingBlockNumber)
-	result, err := ethapi.DoCall(ctx, p.r.backend, args.Data, pendingBlockNr, nil, p.r.backend.RPCEVMTimeout(), p.r.backend.RPCGasCap())
+	result, err := ethapi.DoCall(ctx, p.r.backend, args.Data, pendingBlockNr, nil, nil, p.r.backend.RPCEVMTimeout(), p.r.backend.RPCGasCap())
 	if err != nil {
 		return nil, err
 	}

internal/ethapi/api.go

@@ -33,6 +33,7 @@ import (
 	"github.com/ethereum/go-ethereum/common"
 	"github.com/ethereum/go-ethereum/common/hexutil"
 	"github.com/ethereum/go-ethereum/common/math"
+	"github.com/ethereum/go-ethereum/consensus"
 	"github.com/ethereum/go-ethereum/consensus/ethash"
 	"github.com/ethereum/go-ethereum/consensus/misc"
 	"github.com/ethereum/go-ethereum/core"
@@ -955,7 +956,39 @@ func (diff *BlockOverrides) Apply(blockCtx *vm.BlockContext) {
 	}
 }
 
-func DoCall(ctx context.Context, b Backend, args TransactionArgs, blockNrOrHash rpc.BlockNumberOrHash, overrides *StateOverride, timeout time.Duration, globalGasCap uint64) (*core.ExecutionResult, error) {
+// ChainContextBackend provides methods required to implement ChainContext.
+type ChainContextBackend interface {
+	Engine() consensus.Engine
+	HeaderByNumber(context.Context, rpc.BlockNumber) (*types.Header, error)
+}
+
+// ChainContext is an implementation of core.ChainContext. It's main use-case
+// is instantiating a vm.BlockContext without having access to the BlockChain object.
+type ChainContext struct {
+	b   ChainContextBackend
+	ctx context.Context
+}
+
+// NewChainContext creates a new ChainContext object.
+func NewChainContext(ctx context.Context, backend ChainContextBackend) *ChainContext {
+	return &ChainContext{ctx: ctx, b: backend}
+}
+
+func (context *ChainContext) Engine() consensus.Engine {
+	return context.b.Engine()
+}
+
+func (context *ChainContext) GetHeader(hash common.Hash, number uint64) *types.Header {
+	// This method is called to get the hash for a block number when executing the BLOCKHASH
+	// opcode. Hence no need to search for non-canonical blocks.
+	header, err := context.b.HeaderByNumber(context.ctx, rpc.BlockNumber(number))
+	if err != nil || header.Hash() != hash {
+		return nil
+	}
+	return header
+}
+
+func DoCall(ctx context.Context, b Backend, args TransactionArgs, blockNrOrHash rpc.BlockNumberOrHash, overrides *StateOverride, blockOverrides *BlockOverrides, timeout time.Duration, globalGasCap uint64) (*core.ExecutionResult, error) {
 	defer func(start time.Time) { log.Debug("Executing EVM call finished", "runtime", time.Since(start)) }(time.Now())
 
 	state, header, err := b.StateAndHeaderByNumberOrHash(ctx, blockNrOrHash)
@@ -982,7 +1015,11 @@ func DoCall(ctx context.Context, b Backend, args TransactionArgs, blockNrOrHash
 	if err != nil {
 		return nil, err
 	}
-	evm, vmError, err := b.GetEVM(ctx, msg, state, header, &vm.Config{NoBaseFee: true})
+	blockCtx := core.NewEVMBlockContext(header, NewChainContext(ctx, b), nil)
+	if blockOverrides != nil {
+		blockOverrides.Apply(&blockCtx)
+	}
+	evm, vmError, err := b.GetEVM(ctx, msg, state, header, &vm.Config{NoBaseFee: true}, &blockCtx)
 	if err != nil {
 		return nil, err
 	}
@@ -1046,8 +1083,8 @@ func (e *revertError) ErrorData() interface{} {
 //
 // Note, this function doesn't make and changes in the state/blockchain and is
 // useful to execute and retrieve values.
-func (s *BlockChainAPI) Call(ctx context.Context, args TransactionArgs, blockNrOrHash rpc.BlockNumberOrHash, overrides *StateOverride) (hexutil.Bytes, error) {
+func (s *BlockChainAPI) Call(ctx context.Context, args TransactionArgs, blockNrOrHash rpc.BlockNumberOrHash, overrides *StateOverride, blockOverrides *BlockOverrides) (hexutil.Bytes, error) {
-	result, err := DoCall(ctx, s.b, args, blockNrOrHash, overrides, s.b.RPCEVMTimeout(), s.b.RPCGasCap())
+	result, err := DoCall(ctx, s.b, args, blockNrOrHash, overrides, blockOverrides, s.b.RPCEVMTimeout(), s.b.RPCGasCap())
 	if err != nil {
 		return nil, err
 	}
@@ -1132,7 +1169,7 @@ func DoEstimateGas(ctx context.Context, b Backend, args TransactionArgs, blockNr
 	executable := func(gas uint64) (bool, *core.ExecutionResult, error) {
 		args.Gas = (*hexutil.Uint64)(&gas)
 
-		result, err := DoCall(ctx, b, args, blockNrOrHash, nil, 0, gasCap)
+		result, err := DoCall(ctx, b, args, blockNrOrHash, nil, nil, 0, gasCap)
 		if err != nil {
 			if errors.Is(err, core.ErrIntrinsicGas) {
 				return true, nil, nil // Special case, raise gas limit
@@ -1478,7 +1515,7 @@ func AccessList(ctx context.Context, b Backend, blockNrOrHash rpc.BlockNumberOrH
 		// Apply the transaction with the access list tracer
 		tracer := logger.NewAccessListTracer(accessList, args.from(), to, precompiles)
 		config := vm.Config{Tracer: tracer, NoBaseFee: true}
-		vmenv, _, err := b.GetEVM(ctx, msg, statedb, header, &config)
+		vmenv, _, err := b.GetEVM(ctx, msg, statedb, header, &config, nil)
 		if err != nil {
 			return nil, 0, nil, err
 		}

internal/ethapi/api_test.go

@@ -17,14 +17,34 @@
 package ethapi
 
 import (
+	"bytes"
+	"context"
+	"crypto/ecdsa"
 	"encoding/json"
+	"errors"
 	"math/big"
+	"reflect"
+	"sort"
 	"testing"
+	"time"
 
+	"github.com/ethereum/go-ethereum"
+	"github.com/ethereum/go-ethereum/accounts"
 	"github.com/ethereum/go-ethereum/common"
+	"github.com/ethereum/go-ethereum/common/hexutil"
+	"github.com/ethereum/go-ethereum/consensus"
+	"github.com/ethereum/go-ethereum/consensus/ethash"
+	"github.com/ethereum/go-ethereum/core"
+	"github.com/ethereum/go-ethereum/core/bloombits"
+	"github.com/ethereum/go-ethereum/core/rawdb"
+	"github.com/ethereum/go-ethereum/core/state"
 	"github.com/ethereum/go-ethereum/core/types"
+	"github.com/ethereum/go-ethereum/core/vm"
 	"github.com/ethereum/go-ethereum/crypto"
+	"github.com/ethereum/go-ethereum/ethdb"
+	"github.com/ethereum/go-ethereum/event"
 	"github.com/ethereum/go-ethereum/params"
+	"github.com/ethereum/go-ethereum/rpc"
 )
 
 func TestTransaction_RoundTripRpcJSON(t *testing.T) {
@@ -157,3 +177,450 @@ func allTransactionTypes(addr common.Address, config *params.ChainConfig) []type
 		},
 	}
 }
+
+type testBackend struct {
+	db    ethdb.Database
+	chain *core.BlockChain
+}
+
+func newTestBackend(t *testing.T, n int, gspec *core.Genesis, generator func(i int, b *core.BlockGen)) *testBackend {
+	var (
+		engine  = ethash.NewFaker()
+		backend = &testBackend{
+			db: rawdb.NewMemoryDatabase(),
+		}
+		cacheConfig = &core.CacheConfig{
+			TrieCleanLimit:    256,
+			TrieDirtyLimit:    256,
+			TrieTimeLimit:     5 * time.Minute,
+			SnapshotLimit:     0,
+			TrieDirtyDisabled: true, // Archive mode
+		}
+	)
+	// Generate blocks for testing
+	_, blocks, _ := core.GenerateChainWithGenesis(gspec, engine, n, generator)
+	chain, err := core.NewBlockChain(backend.db, cacheConfig, gspec, nil, engine, vm.Config{}, nil, nil)
+	if err != nil {
+		t.Fatalf("failed to create tester chain: %v", err)
+	}
+	if n, err := chain.InsertChain(blocks); err != nil {
+		t.Fatalf("block %d: failed to insert into chain: %v", n, err)
+	}
+	backend.chain = chain
+	return backend
+}
+
+func (b testBackend) SyncProgress() ethereum.SyncProgress { return ethereum.SyncProgress{} }
+func (b testBackend) SuggestGasTipCap(ctx context.Context) (*big.Int, error) {
+	return big.NewInt(0), nil
+}
+func (b testBackend) FeeHistory(ctx context.Context, blockCount uint64, lastBlock rpc.BlockNumber, rewardPercentiles []float64) (*big.Int, [][]*big.Int, []*big.Int, []float64, error) {
+	return nil, nil, nil, nil, nil
+}
+func (b testBackend) ChainDb() ethdb.Database           { return b.db }
+func (b testBackend) AccountManager() *accounts.Manager { return nil }
+func (b testBackend) ExtRPCEnabled() bool               { return false }
+func (b testBackend) RPCGasCap() uint64                 { return 10000000 }
+func (b testBackend) RPCEVMTimeout() time.Duration      { return time.Second }
+func (b testBackend) RPCTxFeeCap() float64              { return 0 }
+func (b testBackend) UnprotectedAllowed() bool          { return false }
+func (b testBackend) SetHead(number uint64)             {}
+func (b testBackend) HeaderByNumber(ctx context.Context, number rpc.BlockNumber) (*types.Header, error) {
+	if number == rpc.LatestBlockNumber {
+		return b.chain.CurrentBlock(), nil
+	}
+	return b.chain.GetHeaderByNumber(uint64(number)), nil
+}
+func (b testBackend) HeaderByHash(ctx context.Context, hash common.Hash) (*types.Header, error) {
+	panic("implement me")
+}
+func (b testBackend) HeaderByNumberOrHash(ctx context.Context, blockNrOrHash rpc.BlockNumberOrHash) (*types.Header, error) {
+	panic("implement me")
+}
+func (b testBackend) CurrentHeader() *types.Header { panic("implement me") }
+func (b testBackend) CurrentBlock() *types.Header  { panic("implement me") }
+func (b testBackend) BlockByNumber(ctx context.Context, number rpc.BlockNumber) (*types.Block, error) {
+	if number == rpc.LatestBlockNumber {
+		head := b.chain.CurrentBlock()
+		return b.chain.GetBlock(head.Hash(), head.Number.Uint64()), nil
+	}
+	return b.chain.GetBlockByNumber(uint64(number)), nil
+}
+func (b testBackend) BlockByHash(ctx context.Context, hash common.Hash) (*types.Block, error) {
+	panic("implement me")
+}
+func (b testBackend) BlockByNumberOrHash(ctx context.Context, blockNrOrHash rpc.BlockNumberOrHash) (*types.Block, error) {
+	if blockNr, ok := blockNrOrHash.Number(); ok {
+		return b.BlockByNumber(ctx, blockNr)
+	}
+	panic("implement me")
+}
+func (b testBackend) GetBody(ctx context.Context, hash common.Hash, number rpc.BlockNumber) (*types.Body, error) {
+	return b.chain.GetBlock(hash, uint64(number.Int64())).Body(), nil
+}
+func (b testBackend) StateAndHeaderByNumber(ctx context.Context, number rpc.BlockNumber) (*state.StateDB, *types.Header, error) {
+	if number == rpc.PendingBlockNumber {
+		panic("pending state not implemented")
+	}
+	header, err := b.HeaderByNumber(ctx, number)
+	if err != nil {
+		return nil, nil, err
+	}
+	if header == nil {
+		return nil, nil, errors.New("header not found")
+	}
+	stateDb, err := b.chain.StateAt(header.Root)
+	return stateDb, header, err
+}
+func (b testBackend) StateAndHeaderByNumberOrHash(ctx context.Context, blockNrOrHash rpc.BlockNumberOrHash) (*state.StateDB, *types.Header, error) {
+	if blockNr, ok := blockNrOrHash.Number(); ok {
+		return b.StateAndHeaderByNumber(ctx, blockNr)
+	}
+	panic("only implemented for number")
+}
+func (b testBackend) PendingBlockAndReceipts() (*types.Block, types.Receipts) { panic("implement me") }
+func (b testBackend) GetReceipts(ctx context.Context, hash common.Hash) (types.Receipts, error) {
+	panic("implement me")
+}
+func (b testBackend) GetTd(ctx context.Context, hash common.Hash) *big.Int { panic("implement me") }
+func (b testBackend) GetEVM(ctx context.Context, msg *core.Message, state *state.StateDB, header *types.Header, vmConfig *vm.Config, blockContext *vm.BlockContext) (*vm.EVM, func() error, error) {
+	vmError := func() error { return nil }
+	if vmConfig == nil {
+		vmConfig = b.chain.GetVMConfig()
+	}
+	txContext := core.NewEVMTxContext(msg)
+	context := core.NewEVMBlockContext(header, b.chain, nil)
+	if blockContext != nil {
+		context = *blockContext
+	}
+	return vm.NewEVM(context, txContext, state, b.chain.Config(), *vmConfig), vmError, nil
+}
+func (b testBackend) SubscribeChainEvent(ch chan<- core.ChainEvent) event.Subscription {
+	panic("implement me")
+}
+func (b testBackend) SubscribeChainHeadEvent(ch chan<- core.ChainHeadEvent) event.Subscription {
+	panic("implement me")
+}
+func (b testBackend) SubscribeChainSideEvent(ch chan<- core.ChainSideEvent) event.Subscription {
+	panic("implement me")
+}
+func (b testBackend) SendTx(ctx context.Context, signedTx *types.Transaction) error {
+	panic("implement me")
+}
+func (b testBackend) GetTransaction(ctx context.Context, txHash common.Hash) (*types.Transaction, common.Hash, uint64, uint64, error) {
+	panic("implement me")
+}
+func (b testBackend) GetPoolTransactions() (types.Transactions, error)         { panic("implement me") }
+func (b testBackend) GetPoolTransaction(txHash common.Hash) *types.Transaction { panic("implement me") }
+func (b testBackend) GetPoolNonce(ctx context.Context, addr common.Address) (uint64, error) {
+	panic("implement me")
+}
+func (b testBackend) Stats() (pending int, queued int) { panic("implement me") }
+func (b testBackend) TxPoolContent() (map[common.Address]types.Transactions, map[common.Address]types.Transactions) {
+	panic("implement me")
+}
+func (b testBackend) TxPoolContentFrom(addr common.Address) (types.Transactions, types.Transactions) {
+	panic("implement me")
+}
+func (b testBackend) SubscribeNewTxsEvent(events chan<- core.NewTxsEvent) event.Subscription {
+	panic("implement me")
+}
+func (b testBackend) ChainConfig() *params.ChainConfig { return b.chain.Config() }
+func (b testBackend) Engine() consensus.Engine         { return b.chain.Engine() }
+func (b testBackend) GetLogs(ctx context.Context, blockHash common.Hash, number uint64) ([][]*types.Log, error) {
+	panic("implement me")
+}
+func (b testBackend) SubscribeRemovedLogsEvent(ch chan<- core.RemovedLogsEvent) event.Subscription {
+	panic("implement me")
+}
+func (b testBackend) SubscribeLogsEvent(ch chan<- []*types.Log) event.Subscription {
+	panic("implement me")
+}
+func (b testBackend) SubscribePendingLogsEvent(ch chan<- []*types.Log) event.Subscription {
+	panic("implement me")
+}
+func (b testBackend) BloomStatus() (uint64, uint64) { panic("implement me") }
+func (b testBackend) ServiceFilter(ctx context.Context, session *bloombits.MatcherSession) {
+	panic("implement me")
+}
+
+func TestEstimateGas(t *testing.T) {
+	t.Parallel()
+	// Initialize test accounts
+	var (
+		accounts = newAccounts(2)
+		genesis  = &core.Genesis{
+			Config: params.TestChainConfig,
+			Alloc: core.GenesisAlloc{
+				accounts[0].addr: {Balance: big.NewInt(params.Ether)},
+				accounts[1].addr: {Balance: big.NewInt(params.Ether)},
+			},
+		}
+		genBlocks      = 10
+		signer         = types.HomesteadSigner{}
+		randomAccounts = newAccounts(2)
+	)
+	api := NewBlockChainAPI(newTestBackend(t, genBlocks, genesis, func(i int, b *core.BlockGen) {
+		// Transfer from account[0] to account[1]
+		//    value: 1000 wei
+		//    fee:   0 wei
+		tx, _ := types.SignTx(types.NewTx(&types.LegacyTx{Nonce: uint64(i), To: &accounts[1].addr, Value: big.NewInt(1000), Gas: params.TxGas, GasPrice: b.BaseFee(), Data: nil}), signer, accounts[0].key)
+		b.AddTx(tx)
+	}))
+	var testSuite = []struct {
+		blockNumber rpc.BlockNumber
+		call        TransactionArgs
+		expectErr   error
+		want        uint64
+	}{
+		// simple transfer on latest block
+		{
+			blockNumber: rpc.LatestBlockNumber,
+			call: TransactionArgs{
+				From:  &accounts[0].addr,
+				To:    &accounts[1].addr,
+				Value: (*hexutil.Big)(big.NewInt(1000)),
+			},
+			expectErr: nil,
+			want:      21000,
+		},
+		// simple transfer with insufficient funds on latest block
+		{
+			blockNumber: rpc.LatestBlockNumber,
+			call: TransactionArgs{
+				From:  &randomAccounts[0].addr,
+				To:    &accounts[1].addr,
+				Value: (*hexutil.Big)(big.NewInt(1000)),
+			},
+			expectErr: core.ErrInsufficientFunds,
+			want:      21000,
+		},
+		// empty create
+		{
+			blockNumber: rpc.LatestBlockNumber,
+			call:        TransactionArgs{},
+			expectErr:   nil,
+			want:        53000,
+		},
+	}
+	for i, tc := range testSuite {
+		result, err := api.EstimateGas(context.Background(), tc.call, &rpc.BlockNumberOrHash{BlockNumber: &tc.blockNumber})
+		if tc.expectErr != nil {
+			if err == nil {
+				t.Errorf("test %d: want error %v, have nothing", i, tc.expectErr)
+				continue
+			}
+			if !errors.Is(err, tc.expectErr) {
+				t.Errorf("test %d: error mismatch, want %v, have %v", i, tc.expectErr, err)
+			}
+			continue
+		}
+		if err != nil {
+			t.Errorf("test %d: want no error, have %v", i, err)
+			continue
+		}
+		if uint64(result) != tc.want {
+			t.Errorf("test %d, result mismatch, have\n%v\n, want\n%v\n", i, uint64(result), tc.want)
+		}
+	}
+}
+
+func TestCall(t *testing.T) {
+	t.Parallel()
+	// Initialize test accounts
+	var (
+		accounts = newAccounts(3)
+		genesis  = &core.Genesis{
+			Config: params.TestChainConfig,
+			Alloc: core.GenesisAlloc{
+				accounts[0].addr: {Balance: big.NewInt(params.Ether)},
+				accounts[1].addr: {Balance: big.NewInt(params.Ether)},
+				accounts[2].addr: {Balance: big.NewInt(params.Ether)},
+			},
+		}
+		genBlocks = 10
+		signer    = types.HomesteadSigner{}
+	)
+	api := NewBlockChainAPI(newTestBackend(t, genBlocks, genesis, func(i int, b *core.BlockGen) {
+		// Transfer from account[0] to account[1]
+		//    value: 1000 wei
+		//    fee:   0 wei
+		tx, _ := types.SignTx(types.NewTx(&types.LegacyTx{Nonce: uint64(i), To: &accounts[1].addr, Value: big.NewInt(1000), Gas: params.TxGas, GasPrice: b.BaseFee(), Data: nil}), signer, accounts[0].key)
+		b.AddTx(tx)
+	}))
+	randomAccounts := newAccounts(3)
+	var testSuite = []struct {
+		blockNumber    rpc.BlockNumber
+		overrides      StateOverride
+		call           TransactionArgs
+		blockOverrides BlockOverrides
+		expectErr      error
+		want           string
+	}{
+		// transfer on genesis
+		{
+			blockNumber: rpc.BlockNumber(0),
+			call: TransactionArgs{
+				From:  &accounts[0].addr,
+				To:    &accounts[1].addr,
+				Value: (*hexutil.Big)(big.NewInt(1000)),
+			},
+			expectErr: nil,
+			want:      "0x",
+		},
+		// transfer on the head
+		{
+			blockNumber: rpc.BlockNumber(genBlocks),
+			call: TransactionArgs{
+				From:  &accounts[0].addr,
+				To:    &accounts[1].addr,
+				Value: (*hexutil.Big)(big.NewInt(1000)),
+			},
+			expectErr: nil,
+			want:      "0x",
+		},
+		// transfer on a non-existent block, error expects
+		{
+			blockNumber: rpc.BlockNumber(genBlocks + 1),
+			call: TransactionArgs{
+				From:  &accounts[0].addr,
+				To:    &accounts[1].addr,
+				Value: (*hexutil.Big)(big.NewInt(1000)),
+			},
+			expectErr: errors.New("header not found"),
+		},
+		// transfer on the latest block
+		{
+			blockNumber: rpc.LatestBlockNumber,
+			call: TransactionArgs{
+				From:  &accounts[0].addr,
+				To:    &accounts[1].addr,
+				Value: (*hexutil.Big)(big.NewInt(1000)),
+			},
+			expectErr: nil,
+			want:      "0x",
+		},
+		// Call which can only succeed if state is state overridden
+		{
+			blockNumber: rpc.LatestBlockNumber,
+			call: TransactionArgs{
+				From:  &randomAccounts[0].addr,
+				To:    &randomAccounts[1].addr,
+				Value: (*hexutil.Big)(big.NewInt(1000)),
+			},
+			overrides: StateOverride{
+				randomAccounts[0].addr: OverrideAccount{Balance: newRPCBalance(new(big.Int).Mul(big.NewInt(1), big.NewInt(params.Ether)))},
+			},
+			want: "0x",
+		},
+		// Invalid call without state overriding
+		{
+			blockNumber: rpc.LatestBlockNumber,
+			call: TransactionArgs{
+				From:  &randomAccounts[0].addr,
+				To:    &randomAccounts[1].addr,
+				Value: (*hexutil.Big)(big.NewInt(1000)),
+			},
+			expectErr: core.ErrInsufficientFunds,
+		},
+		// Successful simple contract call
+		//
+		// // SPDX-License-Identifier: GPL-3.0
+		//
+		//  pragma solidity >=0.7.0 <0.8.0;
+		//
+		//  /**
+		//   * @title Storage
+		//   * @dev Store & retrieve value in a variable
+		//   */
+		//  contract Storage {
+		//      uint256 public number;
+		//      constructor() {
+		//          number = block.number;
+		//      }
+		//  }
+		{
+			blockNumber: rpc.LatestBlockNumber,
+			call: TransactionArgs{
+				From: &randomAccounts[0].addr,
+				To:   &randomAccounts[2].addr,
+				Data: hex2Bytes("8381f58a"), // call number()
+			},
+			overrides: StateOverride{
+				randomAccounts[2].addr: OverrideAccount{
+					Code:      hex2Bytes("6080604052348015600f57600080fd5b506004361060285760003560e01c80638381f58a14602d575b600080fd5b60336049565b6040518082815260200191505060405180910390f35b6000548156fea2646970667358221220eab35ffa6ab2adfe380772a48b8ba78e82a1b820a18fcb6f59aa4efb20a5f60064736f6c63430007040033"),
+					StateDiff: &map[common.Hash]common.Hash{common.Hash{}: common.BigToHash(big.NewInt(123))},
+				},
+			},
+			want: "0x000000000000000000000000000000000000000000000000000000000000007b",
+		},
+		// Block overrides should work
+		{
+			blockNumber: rpc.LatestBlockNumber,
+			call: TransactionArgs{
+				From: &accounts[1].addr,
+				Input: &hexutil.Bytes{
+					0x43,             // NUMBER
+					0x60, 0x00, 0x52, // MSTORE offset 0
+					0x60, 0x20, 0x60, 0x00, 0xf3,
+				},
+			},
+			blockOverrides: BlockOverrides{Number: (*hexutil.Big)(big.NewInt(11))},
+			want:           "0x000000000000000000000000000000000000000000000000000000000000000b",
+		},
+	}
+	for i, tc := range testSuite {
+		result, err := api.Call(context.Background(), tc.call, rpc.BlockNumberOrHash{BlockNumber: &tc.blockNumber}, &tc.overrides, &tc.blockOverrides)
+		if tc.expectErr != nil {
+			if err == nil {
+				t.Errorf("test %d: want error %v, have nothing", i, tc.expectErr)
+				continue
+			}
+			if !errors.Is(err, tc.expectErr) {
+				// Second try
+				if !reflect.DeepEqual(err, tc.expectErr) {
+					t.Errorf("test %d: error mismatch, want %v, have %v", i, tc.expectErr, err)
+				}
+			}
+			continue
+		}
+		if err != nil {
+			t.Errorf("test %d: want no error, have %v", i, err)
+			continue
+		}
+		if !reflect.DeepEqual(result.String(), tc.want) {
+			t.Errorf("test %d, result mismatch, have\n%v\n, want\n%v\n", i, result.String(), tc.want)
+		}
+	}
+}
+
+type Account struct {
+	key  *ecdsa.PrivateKey
+	addr common.Address
+}
+
+type Accounts []Account
+
+func (a Accounts) Len() int           { return len(a) }
+func (a Accounts) Swap(i, j int)      { a[i], a[j] = a[j], a[i] }
+func (a Accounts) Less(i, j int) bool { return bytes.Compare(a[i].addr.Bytes(), a[j].addr.Bytes()) < 0 }
+
+func newAccounts(n int) (accounts Accounts) {
+	for i := 0; i < n; i++ {
+		key, _ := crypto.GenerateKey()
+		addr := crypto.PubkeyToAddress(key.PublicKey)
+		accounts = append(accounts, Account{key: key, addr: addr})
+	}
+	sort.Sort(accounts)
+	return accounts
+}
+
+func newRPCBalance(balance *big.Int) **hexutil.Big {
+	rpcBalance := (*hexutil.Big)(balance)
+	return &rpcBalance
+}
+
+func hex2Bytes(str string) *hexutil.Bytes {
+	rpcBytes := hexutil.Bytes(common.Hex2Bytes(str))
+	return &rpcBytes
+}

internal/ethapi/backend.go

@@ -68,7 +68,7 @@ type Backend interface {
 	PendingBlockAndReceipts() (*types.Block, types.Receipts)
 	GetReceipts(ctx context.Context, hash common.Hash) (types.Receipts, error)
 	GetTd(ctx context.Context, hash common.Hash) *big.Int
-	GetEVM(ctx context.Context, msg *core.Message, state *state.StateDB, header *types.Header, vmConfig *vm.Config) (*vm.EVM, func() error, error)
+	GetEVM(ctx context.Context, msg *core.Message, state *state.StateDB, header *types.Header, vmConfig *vm.Config, blockCtx *vm.BlockContext) (*vm.EVM, func() error, error)
 	SubscribeChainEvent(ch chan<- core.ChainEvent) event.Subscription
 	SubscribeChainHeadEvent(ch chan<- core.ChainHeadEvent) event.Subscription
 	SubscribeChainSideEvent(ch chan<- core.ChainSideEvent) event.Subscription

internal/ethapi/transaction_args_test.go

@@ -305,7 +305,7 @@ func (b *backendMock) GetLogs(ctx context.Context, blockHash common.Hash, number
 	return nil, nil
 }
 func (b *backendMock) GetTd(ctx context.Context, hash common.Hash) *big.Int { return nil }
-func (b *backendMock) GetEVM(ctx context.Context, msg *core.Message, state *state.StateDB, header *types.Header, vmConfig *vm.Config) (*vm.EVM, func() error, error) {
+func (b *backendMock) GetEVM(ctx context.Context, msg *core.Message, state *state.StateDB, header *types.Header, vmConfig *vm.Config, blockCtx *vm.BlockContext) (*vm.EVM, func() error, error) {
 	return nil, nil, nil
 }
 func (b *backendMock) SubscribeChainEvent(ch chan<- core.ChainEvent) event.Subscription { return nil }

internal/web3ext/web3ext.go

@@ -608,8 +608,8 @@ web3._extend({
 		new web3._extend.Method({
 			name: 'call',
 			call: 'eth_call',
-			params: 3,
+			params: 4,
-			inputFormatter: [web3._extend.formatters.inputCallFormatter, web3._extend.formatters.inputDefaultBlockNumberFormatter, null],
+			inputFormatter: [web3._extend.formatters.inputCallFormatter, web3._extend.formatters.inputDefaultBlockNumberFormatter, null, null],
 		}),
 	],
 	properties: [

les/api_backend.go

@@ -184,12 +184,15 @@ func (b *LesApiBackend) GetTd(ctx context.Context, hash common.Hash) *big.Int {
 	return nil
 }
 
-func (b *LesApiBackend) GetEVM(ctx context.Context, msg *core.Message, state *state.StateDB, header *types.Header, vmConfig *vm.Config) (*vm.EVM, func() error, error) {
+func (b *LesApiBackend) GetEVM(ctx context.Context, msg *core.Message, state *state.StateDB, header *types.Header, vmConfig *vm.Config, blockCtx *vm.BlockContext) (*vm.EVM, func() error, error) {
 	if vmConfig == nil {
 		vmConfig = new(vm.Config)
 	}
 	txContext := core.NewEVMTxContext(msg)
 	context := core.NewEVMBlockContext(header, b.eth.blockchain, nil)
+	if blockCtx != nil {
+		context = *blockCtx
+	}
 	return vm.NewEVM(context, txContext, state, b.eth.chainConfig, *vmConfig), state.Error, nil
 }