From d8a2305565b1f97c451f8595e0f65358d6842714 Mon Sep 17 00:00:00 2001 From: Martin Holst Swende Date: Thu, 2 Jun 2022 11:39:36 +0200 Subject: [PATCH] eth/tracers: add support for block overrides in debug_traceCall (#24871) This PR adds support for block overrides when doing debug_traceCall. - Previously, debug_traceCall against pending erroneously used a common.Hash{} stateroot when looking up the state, meaning that a totally empty state was used -- so it always failed, - With this change, we reject executing debug_traceCall against pending. - And we add ability to override all evm-visible header fields. --- core/evm.go | 5 ++ eth/tracers/api.go | 15 ++++-- eth/tracers/api_test.go | 107 +++++++++++++++++++++++++--------------- internal/ethapi/api.go | 35 +++++++++++++ 4 files changed, 120 insertions(+), 42 deletions(-) diff --git a/core/evm.go b/core/evm.go index 536ac673e6..21e2639a5f 100644 --- a/core/evm.go +++ b/core/evm.go @@ -84,6 +84,11 @@ func GetHashFn(ref *types.Header, chain ChainContext) func(n uint64) common.Hash var cache []common.Hash return func(n uint64) common.Hash { + if ref.Number.Uint64() <= n { + // This situation can happen if we're doing tracing and using + // block overrides. + return common.Hash{} + } // If there's no hash cache yet, make one if len(cache) == 0 { cache = append(cache, ref.ParentHash) diff --git a/eth/tracers/api.go b/eth/tracers/api.go index 074f193e64..13b8988513 100644 --- a/eth/tracers/api.go +++ b/eth/tracers/api.go @@ -179,6 +179,7 @@ type TraceCallConfig struct { Timeout *string Reexec *uint64 StateOverrides *ethapi.StateOverride + BlockOverrides *ethapi.BlockOverrides } // StdTraceConfig holds extra parameters to standard-json trace functions. @@ -806,7 +807,6 @@ func (api *API) TraceTransaction(ctx context.Context, hash common.Hash, config * // TraceCall lets you trace a given eth_call. It collects the structured logs // created during the execution of EVM if the given transaction was added on // top of the provided block and returns them as a JSON object. -// You can provide -2 as a block number to trace on top of the pending block. func (api *API) TraceCall(ctx context.Context, args ethapi.TransactionArgs, blockNrOrHash rpc.BlockNumberOrHash, config *TraceCallConfig) (interface{}, error) { // Try to retrieve the specified block var ( @@ -816,6 +816,14 @@ func (api *API) TraceCall(ctx context.Context, args ethapi.TransactionArgs, bloc if hash, ok := blockNrOrHash.Hash(); ok { block, err = api.blockByHash(ctx, hash) } else if number, ok := blockNrOrHash.Number(); ok { + if number == rpc.PendingBlockNumber { + // We don't have access to the miner here. For tracing 'future' transactions, + // it can be done with block- and state-overrides instead, which offers + // more flexibility and stability than trying to trace on 'pending', since + // the contents of 'pending' is unstable and probably not a true representation + // of what the next actual block is likely to contain. + return nil, errors.New("tracing on top of pending is not supported") + } block, err = api.blockByNumber(ctx, number) } else { return nil, errors.New("invalid arguments; neither block nor hash specified") @@ -832,18 +840,19 @@ func (api *API) TraceCall(ctx context.Context, args ethapi.TransactionArgs, bloc if err != nil { return nil, err } - // Apply the customized state rules if required. + vmctx := core.NewEVMBlockContext(block.Header(), api.chainContext(ctx), nil) + // Apply the customization rules if required. if config != nil { if err := config.StateOverrides.Apply(statedb); err != nil { return nil, err } + config.BlockOverrides.Apply(&vmctx) } // Execute the trace msg, err := args.ToMessage(api.backend.RPCGasCap(), block.BaseFee()) if err != nil { return nil, err } - vmctx := core.NewEVMBlockContext(block.Header(), api.chainContext(ctx), nil) var traceConfig *TraceConfig if config != nil { diff --git a/eth/tracers/api_test.go b/eth/tracers/api_test.go index af41f05d21..bc12b92751 100644 --- a/eth/tracers/api_test.go +++ b/eth/tracers/api_test.go @@ -196,13 +196,12 @@ func TestTraceCall(t *testing.T) { tx, _ := types.SignTx(types.NewTransaction(uint64(i), accounts[1].addr, big.NewInt(1000), params.TxGas, b.BaseFee(), nil), signer, accounts[0].key) b.AddTx(tx) })) - var testSuite = []struct { blockNumber rpc.BlockNumber call ethapi.TransactionArgs config *TraceCallConfig expectErr error - expect interface{} + expect string }{ // Standard JSON trace upon the genesis, plain transfer. { @@ -214,12 +213,7 @@ func TestTraceCall(t *testing.T) { }, config: nil, expectErr: nil, - expect: &logger.ExecutionResult{ - Gas: params.TxGas, - Failed: false, - ReturnValue: "", - StructLogs: []logger.StructLogRes{}, - }, + expect: `{"gas":21000,"failed":false,"returnValue":"","structLogs":[]}`, }, // Standard JSON trace upon the head, plain transfer. { @@ -231,12 +225,7 @@ func TestTraceCall(t *testing.T) { }, config: nil, expectErr: nil, - expect: &logger.ExecutionResult{ - Gas: params.TxGas, - Failed: false, - ReturnValue: "", - StructLogs: []logger.StructLogRes{}, - }, + expect: `{"gas":21000,"failed":false,"returnValue":"","structLogs":[]}`, }, // Standard JSON trace upon the non-existent block, error expects { @@ -248,7 +237,7 @@ func TestTraceCall(t *testing.T) { }, config: nil, expectErr: fmt.Errorf("block #%d not found", genBlocks+1), - expect: nil, + //expect: nil, }, // Standard JSON trace upon the latest block { @@ -260,14 +249,9 @@ func TestTraceCall(t *testing.T) { }, config: nil, expectErr: nil, - expect: &logger.ExecutionResult{ - Gas: params.TxGas, - Failed: false, - ReturnValue: "", - StructLogs: []logger.StructLogRes{}, - }, + expect: `{"gas":21000,"failed":false,"returnValue":"","structLogs":[]}`, }, - // Standard JSON trace upon the pending block + // Tracing on 'pending' should fail: { blockNumber: rpc.PendingBlockNumber, call: ethapi.TransactionArgs{ @@ -276,36 +260,48 @@ func TestTraceCall(t *testing.T) { Value: (*hexutil.Big)(big.NewInt(1000)), }, config: nil, - expectErr: nil, - expect: &logger.ExecutionResult{ - Gas: params.TxGas, - Failed: false, - ReturnValue: "", - StructLogs: []logger.StructLogRes{}, + expectErr: errors.New("tracing on top of pending is not supported"), + }, + { + blockNumber: rpc.LatestBlockNumber, + call: ethapi.TransactionArgs{ + From: &accounts[0].addr, + Input: &hexutil.Bytes{0x43}, // blocknumber + }, + config: &TraceCallConfig{ + BlockOverrides: ðapi.BlockOverrides{Number: (*hexutil.Big)(big.NewInt(0x1337))}, }, + expectErr: nil, + expect: ` {"gas":53018,"failed":false,"returnValue":"","structLogs":[ + {"pc":0,"op":"NUMBER","gas":24946984,"gasCost":2,"depth":1,"stack":[]}, + {"pc":1,"op":"STOP","gas":24946982,"gasCost":0,"depth":1,"stack":["0x1337"]}]}`, }, } - for _, testspec := range testSuite { + for i, testspec := range testSuite { result, err := api.TraceCall(context.Background(), testspec.call, rpc.BlockNumberOrHash{BlockNumber: &testspec.blockNumber}, testspec.config) if testspec.expectErr != nil { if err == nil { - t.Errorf("Expect error %v, get nothing", testspec.expectErr) + t.Errorf("test %d: expect error %v, got nothing", i, testspec.expectErr) continue } if !reflect.DeepEqual(err, testspec.expectErr) { - t.Errorf("Error mismatch, want %v, get %v", testspec.expectErr, err) + t.Errorf("test %d: error mismatch, want %v, git %v", i, testspec.expectErr, err) } } else { if err != nil { - t.Errorf("Expect no error, get %v", err) + t.Errorf("test %d: expect no error, got %v", i, err) continue } var have *logger.ExecutionResult if err := json.Unmarshal(result.(json.RawMessage), &have); err != nil { - t.Errorf("failed to unmarshal result %v", err) + t.Errorf("test %d: failed to unmarshal result %v", i, err) + } + var want *logger.ExecutionResult + if err := json.Unmarshal([]byte(testspec.expect), &want); err != nil { + t.Errorf("test %d: failed to unmarshal result %v", i, err) } - if !reflect.DeepEqual(have, testspec.expect) { - t.Errorf("Result mismatch, want %v, get %v", testspec.expect, have) + if !reflect.DeepEqual(have, want) { + t.Errorf("test %d: result mismatch, want %v, got %v", i, testspec.expect, string(result.(json.RawMessage))) } } } @@ -446,7 +442,7 @@ func TestTracingWithOverrides(t *testing.T) { type res struct { Gas int Failed bool - returnValue string + ReturnValue string } var testSuite = []struct { blockNumber rpc.BlockNumber @@ -457,7 +453,7 @@ func TestTracingWithOverrides(t *testing.T) { }{ // Call which can only succeed if state is state overridden { - blockNumber: rpc.PendingBlockNumber, + blockNumber: rpc.LatestBlockNumber, call: ethapi.TransactionArgs{ From: &randomAccounts[0].addr, To: &randomAccounts[1].addr, @@ -472,7 +468,7 @@ func TestTracingWithOverrides(t *testing.T) { }, // Invalid call without state overriding { - blockNumber: rpc.PendingBlockNumber, + blockNumber: rpc.LatestBlockNumber, call: ethapi.TransactionArgs{ From: &randomAccounts[0].addr, To: &randomAccounts[1].addr, @@ -498,7 +494,7 @@ func TestTracingWithOverrides(t *testing.T) { // } // } { - blockNumber: rpc.PendingBlockNumber, + blockNumber: rpc.LatestBlockNumber, call: ethapi.TransactionArgs{ From: &randomAccounts[0].addr, To: &randomAccounts[2].addr, @@ -515,6 +511,39 @@ func TestTracingWithOverrides(t *testing.T) { }, want: `{"gas":23347,"failed":false,"returnValue":"000000000000000000000000000000000000000000000000000000000000007b"}`, }, + { // Override blocknumber + blockNumber: rpc.LatestBlockNumber, + call: ethapi.TransactionArgs{ + From: &accounts[0].addr, + // BLOCKNUMBER PUSH1 MSTORE + Input: newRPCBytes(common.Hex2Bytes("4360005260206000f3")), + //&hexutil.Bytes{0x43}, // blocknumber + }, + config: &TraceCallConfig{ + BlockOverrides: ðapi.BlockOverrides{Number: (*hexutil.Big)(big.NewInt(0x1337))}, + }, + want: `{"gas":59537,"failed":false,"returnValue":"0000000000000000000000000000000000000000000000000000000000001337"}`, + }, + { // Override blocknumber, and query a blockhash + blockNumber: rpc.LatestBlockNumber, + call: ethapi.TransactionArgs{ + From: &accounts[0].addr, + Input: &hexutil.Bytes{ + 0x60, 0x00, 0x40, // BLOCKHASH(0) + 0x60, 0x00, 0x52, // STORE memory offset 0 + 0x61, 0x13, 0x36, 0x40, // BLOCKHASH(0x1336) + 0x60, 0x20, 0x52, // STORE memory offset 32 + 0x61, 0x13, 0x37, 0x40, // BLOCKHASH(0x1337) + 0x60, 0x40, 0x52, // STORE memory offset 64 + 0x60, 0x60, 0x60, 0x00, 0xf3, // RETURN (0-96) + + }, // blocknumber + }, + config: &TraceCallConfig{ + BlockOverrides: ðapi.BlockOverrides{Number: (*hexutil.Big)(big.NewInt(0x1337))}, + }, + want: `{"gas":72666,"failed":false,"returnValue":"000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000"}`, + }, } for i, tc := range testSuite { result, err := api.TraceCall(context.Background(), tc.call, rpc.BlockNumberOrHash{BlockNumber: &tc.blockNumber}, tc.config) diff --git a/internal/ethapi/api.go b/internal/ethapi/api.go index 1b7c177867..7c422e642d 100644 --- a/internal/ethapi/api.go +++ b/internal/ethapi/api.go @@ -888,6 +888,41 @@ func (diff *StateOverride) Apply(state *state.StateDB) error { return nil } +// BlockOverrides is a set of header fields to override. +type BlockOverrides struct { + Number *hexutil.Big + Difficulty *hexutil.Big + Time *hexutil.Big + GasLimit *hexutil.Uint64 + Coinbase *common.Address + Random *common.Hash +} + +// Apply overrides the given header fields into the given block context. +func (diff *BlockOverrides) Apply(blockCtx *vm.BlockContext) { + if diff == nil { + return + } + if diff.Number != nil { + blockCtx.BlockNumber = diff.Number.ToInt() + } + if diff.Difficulty != nil { + blockCtx.Difficulty = diff.Difficulty.ToInt() + } + if diff.Time != nil { + blockCtx.Time = diff.Time.ToInt() + } + if diff.GasLimit != nil { + blockCtx.GasLimit = uint64(*diff.GasLimit) + } + if diff.Coinbase != nil { + blockCtx.Coinbase = *diff.Coinbase + } + if diff.Random != nil { + blockCtx.Random = diff.Random + } +} + func DoCall(ctx context.Context, b Backend, args TransactionArgs, blockNrOrHash rpc.BlockNumberOrHash, overrides *StateOverride, 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())