go-ethereum/eth/tracers/logger/logger.go

467 lines
15 KiB
Go

// Copyright 2021 The go-ethereum Authors
// This file is part of the go-ethereum library.
//
// The go-ethereum library is free software: you can redistribute it and/or modify
// it under the terms of the GNU Lesser General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// The go-ethereum library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU Lesser General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public License
// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
package logger
import (
"encoding/hex"
"encoding/json"
"fmt"
"io"
"math/big"
"strings"
"sync/atomic"
"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/core/types"
"github.com/ethereum/go-ethereum/core/vm"
"github.com/ethereum/go-ethereum/params"
"github.com/holiman/uint256"
)
// Storage represents a contract's storage.
type Storage map[common.Hash]common.Hash
// Copy duplicates the current storage.
func (s Storage) Copy() Storage {
cpy := make(Storage, len(s))
for key, value := range s {
cpy[key] = value
}
return cpy
}
// Config are the configuration options for structured logger the EVM
type Config struct {
EnableMemory bool // enable memory capture
DisableStack bool // disable stack capture
DisableStorage bool // disable storage capture
EnableReturnData bool // enable return data capture
Debug bool // print output during capture end
Limit int // maximum length of output, but zero means unlimited
// Chain overrides, can be used to execute a trace using future fork rules
Overrides *params.ChainConfig `json:"overrides,omitempty"`
}
//go:generate go run github.com/fjl/gencodec -type StructLog -field-override structLogMarshaling -out gen_structlog.go
// StructLog is emitted to the EVM each cycle and lists information about the current internal state
// prior to the execution of the statement.
type StructLog struct {
Pc uint64 `json:"pc"`
Op vm.OpCode `json:"op"`
Gas uint64 `json:"gas"`
GasCost uint64 `json:"gasCost"`
Memory []byte `json:"memory,omitempty"`
MemorySize int `json:"memSize"`
Stack []uint256.Int `json:"stack"`
ReturnData []byte `json:"returnData,omitempty"`
Storage map[common.Hash]common.Hash `json:"-"`
Depth int `json:"depth"`
RefundCounter uint64 `json:"refund"`
Err error `json:"-"`
}
// overrides for gencodec
type structLogMarshaling struct {
Gas math.HexOrDecimal64
GasCost math.HexOrDecimal64
Memory hexutil.Bytes
ReturnData hexutil.Bytes
OpName string `json:"opName"` // adds call to OpName() in MarshalJSON
ErrorString string `json:"error,omitempty"` // adds call to ErrorString() in MarshalJSON
}
// OpName formats the operand name in a human-readable format.
func (s *StructLog) OpName() string {
return s.Op.String()
}
// ErrorString formats the log's error as a string.
func (s *StructLog) ErrorString() string {
if s.Err != nil {
return s.Err.Error()
}
return ""
}
// StructLogger is an EVM state logger and implements EVMLogger.
//
// StructLogger can capture state based on the given Log configuration and also keeps
// a track record of modified storage which is used in reporting snapshots of the
// contract their storage.
type StructLogger struct {
cfg Config
env *vm.EVM
storage map[common.Address]Storage
logs []StructLog
output []byte
err error
gasLimit uint64
usedGas uint64
interrupt atomic.Bool // Atomic flag to signal execution interruption
reason error // Textual reason for the interruption
}
// NewStructLogger returns a new logger
func NewStructLogger(cfg *Config) *StructLogger {
logger := &StructLogger{
storage: make(map[common.Address]Storage),
}
if cfg != nil {
logger.cfg = *cfg
}
return logger
}
// Reset clears the data held by the logger.
func (l *StructLogger) Reset() {
l.storage = make(map[common.Address]Storage)
l.output = make([]byte, 0)
l.logs = l.logs[:0]
l.err = nil
}
// CaptureStart implements the EVMLogger interface to initialize the tracing operation.
func (l *StructLogger) CaptureStart(env *vm.EVM, from common.Address, to common.Address, create bool, input []byte, gas uint64, value *big.Int) {
l.env = env
}
// CaptureState logs a new structured log message and pushes it out to the environment
//
// CaptureState also tracks SLOAD/SSTORE ops to track storage change.
func (l *StructLogger) CaptureState(pc uint64, op vm.OpCode, gas, cost uint64, scope *vm.ScopeContext, rData []byte, depth int, err error) {
// If tracing was interrupted, set the error and stop
if l.interrupt.Load() {
return
}
// check if already accumulated the specified number of logs
if l.cfg.Limit != 0 && l.cfg.Limit <= len(l.logs) {
return
}
memory := scope.Memory
stack := scope.Stack
contract := scope.Contract
// Copy a snapshot of the current memory state to a new buffer
var mem []byte
if l.cfg.EnableMemory {
mem = make([]byte, len(memory.Data()))
copy(mem, memory.Data())
}
// Copy a snapshot of the current stack state to a new buffer
var stck []uint256.Int
if !l.cfg.DisableStack {
stck = make([]uint256.Int, len(stack.Data()))
for i, item := range stack.Data() {
stck[i] = item
}
}
stackData := stack.Data()
stackLen := len(stackData)
// Copy a snapshot of the current storage to a new container
var storage Storage
if !l.cfg.DisableStorage && (op == vm.SLOAD || op == vm.SSTORE) {
// initialise new changed values storage container for this contract
// if not present.
if l.storage[contract.Address()] == nil {
l.storage[contract.Address()] = make(Storage)
}
// capture SLOAD opcodes and record the read entry in the local storage
if op == vm.SLOAD && stackLen >= 1 {
var (
address = common.Hash(stackData[stackLen-1].Bytes32())
value = l.env.StateDB.GetState(contract.Address(), address)
)
l.storage[contract.Address()][address] = value
storage = l.storage[contract.Address()].Copy()
} else if op == vm.SSTORE && stackLen >= 2 {
// capture SSTORE opcodes and record the written entry in the local storage.
var (
value = common.Hash(stackData[stackLen-2].Bytes32())
address = common.Hash(stackData[stackLen-1].Bytes32())
)
l.storage[contract.Address()][address] = value
storage = l.storage[contract.Address()].Copy()
}
}
var rdata []byte
if l.cfg.EnableReturnData {
rdata = make([]byte, len(rData))
copy(rdata, rData)
}
// create a new snapshot of the EVM.
log := StructLog{pc, op, gas, cost, mem, memory.Len(), stck, rdata, storage, depth, l.env.StateDB.GetRefund(), err}
l.logs = append(l.logs, log)
}
// CaptureFault implements the EVMLogger interface to trace an execution fault
// while running an opcode.
func (l *StructLogger) CaptureFault(pc uint64, op vm.OpCode, gas, cost uint64, scope *vm.ScopeContext, depth int, err error) {
}
// CaptureEnd is called after the call finishes to finalize the tracing.
func (l *StructLogger) CaptureEnd(output []byte, gasUsed uint64, err error) {
l.output = output
l.err = err
if l.cfg.Debug {
fmt.Printf("%#x\n", output)
if err != nil {
fmt.Printf(" error: %v\n", err)
}
}
}
func (l *StructLogger) CaptureEnter(typ vm.OpCode, from common.Address, to common.Address, input []byte, gas uint64, value *big.Int) {
}
func (l *StructLogger) CaptureExit(output []byte, gasUsed uint64, err error) {
}
func (l *StructLogger) GetResult() (json.RawMessage, error) {
// Tracing aborted
if l.reason != nil {
return nil, l.reason
}
failed := l.err != nil
returnData := common.CopyBytes(l.output)
// Return data when successful and revert reason when reverted, otherwise empty.
returnVal := fmt.Sprintf("%x", returnData)
if failed && l.err != vm.ErrExecutionReverted {
returnVal = ""
}
return json.Marshal(&ExecutionResult{
Gas: l.usedGas,
Failed: failed,
ReturnValue: returnVal,
StructLogs: formatLogs(l.StructLogs()),
})
}
// Stop terminates execution of the tracer at the first opportune moment.
func (l *StructLogger) Stop(err error) {
l.reason = err
l.interrupt.Store(true)
}
func (l *StructLogger) CaptureTxStart(gasLimit uint64) {
l.gasLimit = gasLimit
}
func (l *StructLogger) CaptureTxEnd(restGas uint64) {
l.usedGas = l.gasLimit - restGas
}
// StructLogs returns the captured log entries.
func (l *StructLogger) StructLogs() []StructLog { return l.logs }
// Error returns the VM error captured by the trace.
func (l *StructLogger) Error() error { return l.err }
// Output returns the VM return value captured by the trace.
func (l *StructLogger) Output() []byte { return l.output }
// WriteTrace writes a formatted trace to the given writer
func WriteTrace(writer io.Writer, logs []StructLog) {
for _, log := range logs {
fmt.Fprintf(writer, "%-16spc=%08d gas=%v cost=%v", log.Op, log.Pc, log.Gas, log.GasCost)
if log.Err != nil {
fmt.Fprintf(writer, " ERROR: %v", log.Err)
}
fmt.Fprintln(writer)
if len(log.Stack) > 0 {
fmt.Fprintln(writer, "Stack:")
for i := len(log.Stack) - 1; i >= 0; i-- {
fmt.Fprintf(writer, "%08d %s\n", len(log.Stack)-i-1, log.Stack[i].Hex())
}
}
if len(log.Memory) > 0 {
fmt.Fprintln(writer, "Memory:")
fmt.Fprint(writer, hex.Dump(log.Memory))
}
if len(log.Storage) > 0 {
fmt.Fprintln(writer, "Storage:")
for h, item := range log.Storage {
fmt.Fprintf(writer, "%x: %x\n", h, item)
}
}
if len(log.ReturnData) > 0 {
fmt.Fprintln(writer, "ReturnData:")
fmt.Fprint(writer, hex.Dump(log.ReturnData))
}
fmt.Fprintln(writer)
}
}
// WriteLogs writes vm logs in a readable format to the given writer
func WriteLogs(writer io.Writer, logs []*types.Log) {
for _, log := range logs {
fmt.Fprintf(writer, "LOG%d: %x bn=%d txi=%x\n", len(log.Topics), log.Address, log.BlockNumber, log.TxIndex)
for i, topic := range log.Topics {
fmt.Fprintf(writer, "%08d %x\n", i, topic)
}
fmt.Fprint(writer, hex.Dump(log.Data))
fmt.Fprintln(writer)
}
}
type mdLogger struct {
out io.Writer
cfg *Config
env *vm.EVM
}
// NewMarkdownLogger creates a logger which outputs information in a format adapted
// for human readability, and is also a valid markdown table
func NewMarkdownLogger(cfg *Config, writer io.Writer) *mdLogger {
l := &mdLogger{out: writer, cfg: cfg}
if l.cfg == nil {
l.cfg = &Config{}
}
return l
}
func (t *mdLogger) CaptureStart(env *vm.EVM, from common.Address, to common.Address, create bool, input []byte, gas uint64, value *big.Int) {
t.env = env
if !create {
fmt.Fprintf(t.out, "From: `%v`\nTo: `%v`\nData: `%#x`\nGas: `%d`\nValue `%v` wei\n",
from.String(), to.String(),
input, gas, value)
} else {
fmt.Fprintf(t.out, "From: `%v`\nCreate at: `%v`\nData: `%#x`\nGas: `%d`\nValue `%v` wei\n",
from.String(), to.String(),
input, gas, value)
}
fmt.Fprintf(t.out, `
| Pc | Op | Cost | Stack | RStack | Refund |
|-------|-------------|------|-----------|-----------|---------|
`)
}
// CaptureState also tracks SLOAD/SSTORE ops to track storage change.
func (t *mdLogger) CaptureState(pc uint64, op vm.OpCode, gas, cost uint64, scope *vm.ScopeContext, rData []byte, depth int, err error) {
stack := scope.Stack
fmt.Fprintf(t.out, "| %4d | %10v | %3d |", pc, op, cost)
if !t.cfg.DisableStack {
// format stack
var a []string
for _, elem := range stack.Data() {
a = append(a, elem.Hex())
}
b := fmt.Sprintf("[%v]", strings.Join(a, ","))
fmt.Fprintf(t.out, "%10v |", b)
}
fmt.Fprintf(t.out, "%10v |", t.env.StateDB.GetRefund())
fmt.Fprintln(t.out, "")
if err != nil {
fmt.Fprintf(t.out, "Error: %v\n", err)
}
}
func (t *mdLogger) CaptureFault(pc uint64, op vm.OpCode, gas, cost uint64, scope *vm.ScopeContext, depth int, err error) {
fmt.Fprintf(t.out, "\nError: at pc=%d, op=%v: %v\n", pc, op, err)
}
func (t *mdLogger) CaptureEnd(output []byte, gasUsed uint64, err error) {
fmt.Fprintf(t.out, "\nOutput: `%#x`\nConsumed gas: `%d`\nError: `%v`\n",
output, gasUsed, err)
}
func (t *mdLogger) CaptureEnter(typ vm.OpCode, from common.Address, to common.Address, input []byte, gas uint64, value *big.Int) {
}
func (t *mdLogger) CaptureExit(output []byte, gasUsed uint64, err error) {}
func (*mdLogger) CaptureTxStart(gasLimit uint64) {}
func (*mdLogger) CaptureTxEnd(restGas uint64) {}
// ExecutionResult groups all structured logs emitted by the EVM
// while replaying a transaction in debug mode as well as transaction
// execution status, the amount of gas used and the return value
type ExecutionResult struct {
Gas uint64 `json:"gas"`
Failed bool `json:"failed"`
ReturnValue string `json:"returnValue"`
StructLogs []StructLogRes `json:"structLogs"`
}
// StructLogRes stores a structured log emitted by the EVM while replaying a
// transaction in debug mode
type StructLogRes struct {
Pc uint64 `json:"pc"`
Op string `json:"op"`
Gas uint64 `json:"gas"`
GasCost uint64 `json:"gasCost"`
Depth int `json:"depth"`
Error string `json:"error,omitempty"`
Stack *[]string `json:"stack,omitempty"`
ReturnData string `json:"returnData,omitempty"`
Memory *[]string `json:"memory,omitempty"`
Storage *map[string]string `json:"storage,omitempty"`
RefundCounter uint64 `json:"refund,omitempty"`
}
// formatLogs formats EVM returned structured logs for json output
func formatLogs(logs []StructLog) []StructLogRes {
formatted := make([]StructLogRes, len(logs))
for index, trace := range logs {
formatted[index] = StructLogRes{
Pc: trace.Pc,
Op: trace.Op.String(),
Gas: trace.Gas,
GasCost: trace.GasCost,
Depth: trace.Depth,
Error: trace.ErrorString(),
RefundCounter: trace.RefundCounter,
}
if trace.Stack != nil {
stack := make([]string, len(trace.Stack))
for i, stackValue := range trace.Stack {
stack[i] = stackValue.Hex()
}
formatted[index].Stack = &stack
}
if trace.ReturnData != nil && len(trace.ReturnData) > 0 {
formatted[index].ReturnData = hexutil.Bytes(trace.ReturnData).String()
}
if trace.Memory != nil {
memory := make([]string, 0, (len(trace.Memory)+31)/32)
for i := 0; i+32 <= len(trace.Memory); i += 32 {
memory = append(memory, fmt.Sprintf("%x", trace.Memory[i:i+32]))
}
formatted[index].Memory = &memory
}
if trace.Storage != nil {
storage := make(map[string]string)
for i, storageValue := range trace.Storage {
storage[fmt.Sprintf("%x", i)] = fmt.Sprintf("%x", storageValue)
}
formatted[index].Storage = &storage
}
}
return formatted
}