plugeth/core/vm/logger.go
Martin Holst Swende 0fda25e471
eth/tracers, core: use scopecontext in tracers, provide statedb in capturestart (#22333)
Fixes the CaptureStart api to include the EVM, thus being able to set the statedb early on. This pr also exposes the struct we used internally in the interpreter to encapsulate the contract, mem, stack, rstack, so we pass it as a single struct to the tracer, and removes the error returns on the capture methods.
2021-03-25 10:13:14 +01:00

337 lines
11 KiB
Go

// Copyright 2015 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 vm
import (
"encoding/hex"
"fmt"
"io"
"math/big"
"strings"
"time"
"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/params"
)
// 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)
for key, value := range s {
cpy[key] = value
}
return cpy
}
// LogConfig are the configuration options for structured logger the EVM
type LogConfig struct {
DisableMemory bool // disable memory capture
DisableStack bool // disable stack capture
DisableStorage bool // disable storage capture
DisableReturnData bool // disable 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 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 OpCode `json:"op"`
Gas uint64 `json:"gas"`
GasCost uint64 `json:"gasCost"`
Memory []byte `json:"memory"`
MemorySize int `json:"memSize"`
Stack []*big.Int `json:"stack"`
ReturnData []byte `json:"returnData"`
Storage map[common.Hash]common.Hash `json:"-"`
Depth int `json:"depth"`
RefundCounter uint64 `json:"refund"`
Err error `json:"-"`
}
// overrides for gencodec
type structLogMarshaling struct {
Stack []*math.HexOrDecimal256
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"` // 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 ""
}
// Tracer is used to collect execution traces from an EVM transaction
// execution. CaptureState is called for each step of the VM with the
// current VM state.
// Note that reference types are actual VM data structures; make copies
// if you need to retain them beyond the current call.
type Tracer interface {
CaptureStart(env *EVM, from common.Address, to common.Address, create bool, input []byte, gas uint64, value *big.Int)
CaptureState(env *EVM, pc uint64, op OpCode, gas, cost uint64, scope *ScopeContext, rData []byte, depth int, err error)
CaptureFault(env *EVM, pc uint64, op OpCode, gas, cost uint64, scope *ScopeContext, depth int, err error)
CaptureEnd(output []byte, gasUsed uint64, t time.Duration, err error)
}
// StructLogger is an EVM state logger and implements Tracer.
//
// 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 LogConfig
storage map[common.Address]Storage
logs []StructLog
output []byte
err error
}
// NewStructLogger returns a new logger
func NewStructLogger(cfg *LogConfig) *StructLogger {
logger := &StructLogger{
storage: make(map[common.Address]Storage),
}
if cfg != nil {
logger.cfg = *cfg
}
return logger
}
// CaptureStart implements the Tracer interface to initialize the tracing operation.
func (l *StructLogger) CaptureStart(env *EVM, from common.Address, to common.Address, create bool, input []byte, gas uint64, value *big.Int) {
}
// 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(env *EVM, pc uint64, op OpCode, gas, cost uint64, scope *ScopeContext, rData []byte, depth int, err error) {
memory := scope.Memory
stack := scope.Stack
contract := scope.Contract
// check if already accumulated the specified number of logs
if l.cfg.Limit != 0 && l.cfg.Limit <= len(l.logs) {
return
}
// Copy a snapshot of the current memory state to a new buffer
var mem []byte
if !l.cfg.DisableMemory {
mem = make([]byte, len(memory.Data()))
copy(mem, memory.Data())
}
// Copy a snapshot of the current stack state to a new buffer
var stck []*big.Int
if !l.cfg.DisableStack {
stck = make([]*big.Int, len(stack.Data()))
for i, item := range stack.Data() {
stck[i] = new(big.Int).Set(item.ToBig())
}
}
// Copy a snapshot of the current storage to a new container
var storage Storage
if !l.cfg.DisableStorage {
// 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 == SLOAD && stack.len() >= 1 {
var (
address = common.Hash(stack.data[stack.len()-1].Bytes32())
value = env.StateDB.GetState(contract.Address(), address)
)
l.storage[contract.Address()][address] = value
}
// capture SSTORE opcodes and record the written entry in the local storage.
if op == SSTORE && stack.len() >= 2 {
var (
value = common.Hash(stack.data[stack.len()-2].Bytes32())
address = common.Hash(stack.data[stack.len()-1].Bytes32())
)
l.storage[contract.Address()][address] = value
}
storage = l.storage[contract.Address()].Copy()
}
var rdata []byte
if !l.cfg.DisableReturnData {
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, env.StateDB.GetRefund(), err}
l.logs = append(l.logs, log)
}
// CaptureFault implements the Tracer interface to trace an execution fault
// while running an opcode.
func (l *StructLogger) CaptureFault(env *EVM, pc uint64, op OpCode, gas, cost uint64, scope *ScopeContext, depth int, err error) {
}
// CaptureEnd is called after the call finishes to finalize the tracing.
func (l *StructLogger) CaptureEnd(output []byte, gasUsed uint64, t time.Duration, err error) {
l.output = output
l.err = err
if l.cfg.Debug {
fmt.Printf("0x%x\n", output)
if err != nil {
fmt.Printf(" error: %v\n", err)
}
}
}
// 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 %x\n", len(log.Stack)-i-1, math.PaddedBigBytes(log.Stack[i], 32))
}
}
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 *LogConfig
}
// NewMarkdownLogger creates a logger which outputs information in a format adapted
// for human readability, and is also a valid markdown table
func NewMarkdownLogger(cfg *LogConfig, writer io.Writer) *mdLogger {
l := &mdLogger{writer, cfg}
if l.cfg == nil {
l.cfg = &LogConfig{}
}
return l
}
func (t *mdLogger) CaptureStart(env *EVM, from common.Address, to common.Address, create bool, input []byte, gas uint64, value *big.Int) {
if !create {
fmt.Fprintf(t.out, "From: `%v`\nTo: `%v`\nData: `0x%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: `0x%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(env *EVM, pc uint64, op OpCode, gas, cost uint64, scope *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, fmt.Sprintf("%v", elem.String()))
}
b := fmt.Sprintf("[%v]", strings.Join(a, ","))
fmt.Fprintf(t.out, "%10v |", b)
}
fmt.Fprintf(t.out, "%10v |", env.StateDB.GetRefund())
fmt.Fprintln(t.out, "")
if err != nil {
fmt.Fprintf(t.out, "Error: %v\n", err)
}
}
func (t *mdLogger) CaptureFault(env *EVM, pc uint64, op OpCode, gas, cost uint64, scope *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, tm time.Duration, err error) {
fmt.Fprintf(t.out, "\nOutput: `0x%x`\nConsumed gas: `%d`\nError: `%v`\n",
output, gasUsed, err)
}