go-ethereum/eth/tracers/native/erc7562.go

530 lines
16 KiB
Go

// Copyright 2025 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 native
import (
"bytes"
"encoding/json"
"errors"
"math/big"
"slices"
"sync/atomic"
"github.com/ethereum/go-ethereum/accounts/abi"
"github.com/ethereum/go-ethereum/common"
"github.com/ethereum/go-ethereum/common/hexutil"
"github.com/ethereum/go-ethereum/core/tracing"
"github.com/ethereum/go-ethereum/core/types"
"github.com/ethereum/go-ethereum/core/vm"
"github.com/ethereum/go-ethereum/eth/tracers"
"github.com/ethereum/go-ethereum/eth/tracers/internal"
"github.com/ethereum/go-ethereum/log"
"github.com/ethereum/go-ethereum/params"
"github.com/holiman/uint256"
)
//go:generate go run github.com/fjl/gencodec -type callFrameWithOpcodes -field-override callFrameWithOpcodesMarshaling -out gen_callframewithopcodes_json.go
func init() {
tracers.DefaultDirectory.Register("erc7562Tracer", newErc7562Tracer, false)
}
type contractSizeWithOpcode struct {
ContractSize int `json:"contractSize"`
Opcode vm.OpCode `json:"opcode"`
}
type callFrameWithOpcodes struct {
Type vm.OpCode `json:"-"`
From common.Address `json:"from"`
Gas uint64 `json:"gas"`
GasUsed uint64 `json:"gasUsed"`
To *common.Address `json:"to,omitempty" rlp:"optional"`
Input []byte `json:"input" rlp:"optional"`
Output []byte `json:"output,omitempty" rlp:"optional"`
Error string `json:"error,omitempty" rlp:"optional"`
RevertReason string `json:"revertReason,omitempty"`
Logs []callLog `json:"logs,omitempty" rlp:"optional"`
Value *big.Int `json:"value,omitempty" rlp:"optional"`
revertedSnapshot bool
AccessedSlots accessedSlots `json:"accessedSlots"`
ExtCodeAccessInfo []common.Address `json:"extCodeAccessInfo"`
UsedOpcodes map[vm.OpCode]uint64 `json:"usedOpcodes"`
ContractSize map[common.Address]*contractSizeWithOpcode `json:"contractSize"`
OutOfGas bool `json:"outOfGas"`
// Keccak preimages for the whole transaction are stored in the
// root call frame.
KeccakPreimages [][]byte `json:"keccak,omitempty"`
Calls []callFrameWithOpcodes `json:"calls,omitempty" rlp:"optional"`
}
func (f callFrameWithOpcodes) TypeString() string {
return f.Type.String()
}
func (f callFrameWithOpcodes) failed() bool {
return len(f.Error) > 0 && f.revertedSnapshot
}
func (f *callFrameWithOpcodes) processOutput(output []byte, err error, reverted bool) {
output = common.CopyBytes(output)
// Clear error if tx wasn't reverted. This happened
// for pre-homestead contract storage OOG.
if err != nil && !reverted {
err = nil
}
if err == nil {
f.Output = output
return
}
f.Error = err.Error()
f.revertedSnapshot = reverted
if f.Type == vm.CREATE || f.Type == vm.CREATE2 {
f.To = nil
}
if !errors.Is(err, vm.ErrExecutionReverted) || len(output) == 0 {
return
}
f.Output = output
if len(output) < 4 {
return
}
if unpacked, err := abi.UnpackRevert(output); err == nil {
f.RevertReason = unpacked
}
}
type callFrameWithOpcodesMarshaling struct {
TypeString string `json:"type"`
Gas hexutil.Uint64
GasUsed hexutil.Uint64
Value *hexutil.Big
Input hexutil.Bytes
Output hexutil.Bytes
UsedOpcodes map[hexutil.Uint64]uint64
KeccakPreimages []hexutil.Bytes
}
type accessedSlots struct {
Reads map[common.Hash][]common.Hash `json:"reads"`
Writes map[common.Hash]uint64 `json:"writes"`
TransientReads map[common.Hash]uint64 `json:"transientReads"`
TransientWrites map[common.Hash]uint64 `json:"transientWrites"`
}
type opcodeWithPartialStack struct {
Opcode vm.OpCode
StackTopItems []uint256.Int
}
type erc7562Tracer struct {
config erc7562TracerConfig
gasLimit uint64
interrupt atomic.Bool // Atomic flag to signal execution interruption
reason error // Textual reason for the interruption
env *tracing.VMContext
ignoredOpcodes map[vm.OpCode]struct{}
callstackWithOpcodes []callFrameWithOpcodes
lastOpWithStack *opcodeWithPartialStack
keccakPreimages map[string]struct{}
}
// newErc7562Tracer returns a native go tracer which tracks
// call frames of a tx, and implements vm.EVMLogger.
func newErc7562Tracer(ctx *tracers.Context, cfg json.RawMessage, _ *params.ChainConfig) (*tracers.Tracer, error) {
t, err := newErc7562TracerObject(cfg)
if err != nil {
return nil, err
}
return &tracers.Tracer{
Hooks: &tracing.Hooks{
OnTxStart: t.OnTxStart,
OnOpcode: t.OnOpcode,
OnTxEnd: t.OnTxEnd,
OnEnter: t.OnEnter,
OnExit: t.OnExit,
OnLog: t.OnLog,
},
GetResult: t.GetResult,
Stop: t.Stop,
}, nil
}
type erc7562TracerConfig struct {
StackTopItemsSize int `json:"stackTopItemsSize"`
IgnoredOpcodes []hexutil.Uint64 `json:"ignoredOpcodes"` // Opcodes to ignore during OnOpcode hook execution
WithLog bool `json:"withLog"` // If true, erc7562 tracer will collect event logs
}
func getFullConfiguration(partial erc7562TracerConfig) erc7562TracerConfig {
config := partial
if config.IgnoredOpcodes == nil {
config.IgnoredOpcodes = defaultIgnoredOpcodes()
}
if config.StackTopItemsSize == 0 {
config.StackTopItemsSize = 3
}
return config
}
func newErc7562TracerObject(cfg json.RawMessage) (*erc7562Tracer, error) {
var config erc7562TracerConfig
if cfg != nil {
if err := json.Unmarshal(cfg, &config); err != nil {
return nil, err
}
}
fullConfig := getFullConfiguration(config)
// Create a map of ignored opcodes for fast lookup
ignoredOpcodes := make(map[vm.OpCode]struct{}, len(fullConfig.IgnoredOpcodes))
for _, op := range fullConfig.IgnoredOpcodes {
ignoredOpcodes[vm.OpCode(op)] = struct{}{}
}
// First callframe contains tx context info
// and is populated on start and end.
return &erc7562Tracer{
callstackWithOpcodes: make([]callFrameWithOpcodes, 0, 1),
config: fullConfig,
keccakPreimages: make(map[string]struct{}),
ignoredOpcodes: ignoredOpcodes,
}, nil
}
func (t *erc7562Tracer) OnTxStart(env *tracing.VMContext, tx *types.Transaction, from common.Address) {
t.env = env
t.gasLimit = tx.Gas()
}
// OnEnter is called when EVM enters a new scope (via call, create or selfdestruct).
func (t *erc7562Tracer) OnEnter(depth int, typ byte, from common.Address, to common.Address, input []byte, gas uint64, value *big.Int) {
// Skip if tracing was interrupted
if t.interrupt.Load() {
return
}
toCopy := to
call := callFrameWithOpcodes{
Type: vm.OpCode(typ),
From: from,
To: &toCopy,
Input: common.CopyBytes(input),
Gas: gas,
Value: value,
AccessedSlots: accessedSlots{
Reads: map[common.Hash][]common.Hash{},
Writes: map[common.Hash]uint64{},
TransientReads: map[common.Hash]uint64{},
TransientWrites: map[common.Hash]uint64{},
},
UsedOpcodes: map[vm.OpCode]uint64{},
ExtCodeAccessInfo: make([]common.Address, 0),
ContractSize: map[common.Address]*contractSizeWithOpcode{},
}
if depth == 0 {
call.Gas = t.gasLimit
}
t.callstackWithOpcodes = append(t.callstackWithOpcodes, call)
}
func (t *erc7562Tracer) captureEnd(output []byte, err error, reverted bool) {
if len(t.callstackWithOpcodes) != 1 {
return
}
t.callstackWithOpcodes[0].processOutput(output, err, reverted)
}
// OnExit is called when EVM exits a scope, even if the scope didn't
// execute any code.
func (t *erc7562Tracer) OnExit(depth int, output []byte, gasUsed uint64, err error, reverted bool) {
if t.interrupt.Load() {
return
}
if depth == 0 {
t.captureEnd(output, err, reverted)
return
}
size := len(t.callstackWithOpcodes)
if size <= 1 {
return
}
// Pop call.
call := t.callstackWithOpcodes[size-1]
t.callstackWithOpcodes = t.callstackWithOpcodes[:size-1]
size -= 1
if errors.Is(err, vm.ErrCodeStoreOutOfGas) || errors.Is(err, vm.ErrOutOfGas) {
call.OutOfGas = true
}
call.GasUsed = gasUsed
call.processOutput(output, err, reverted)
// Nest call into parent.
t.callstackWithOpcodes[size-1].Calls = append(t.callstackWithOpcodes[size-1].Calls, call)
}
func (t *erc7562Tracer) OnTxEnd(receipt *types.Receipt, err error) {
if t.interrupt.Load() {
return
}
// Error happened during tx validation.
if err != nil {
return
}
t.callstackWithOpcodes[0].GasUsed = receipt.GasUsed
if t.config.WithLog {
// Logs are not emitted when the call fails
t.clearFailedLogs(&t.callstackWithOpcodes[0], false)
}
}
func (t *erc7562Tracer) OnLog(log1 *types.Log) {
// Only logs need to be captured via opcode processing
if !t.config.WithLog {
return
}
// Skip if tracing was interrupted
if t.interrupt.Load() {
return
}
l := callLog{
Address: log1.Address,
Topics: log1.Topics,
Data: log1.Data,
Position: hexutil.Uint(len(t.callstackWithOpcodes[len(t.callstackWithOpcodes)-1].Calls)),
}
t.callstackWithOpcodes[len(t.callstackWithOpcodes)-1].Logs = append(t.callstackWithOpcodes[len(t.callstackWithOpcodes)-1].Logs, l)
}
// GetResult returns the json-encoded nested list of call traces, and any
// error arising from the encoding or forceful termination (via `Stop`).
func (t *erc7562Tracer) GetResult() (json.RawMessage, error) {
if t.interrupt.Load() {
return nil, t.reason
}
if len(t.callstackWithOpcodes) != 1 {
return nil, errors.New("incorrect number of top-level calls")
}
keccak := make([][]byte, 0, len(t.callstackWithOpcodes[0].KeccakPreimages))
for k := range t.keccakPreimages {
keccak = append(keccak, []byte(k))
}
t.callstackWithOpcodes[0].KeccakPreimages = keccak
slices.SortFunc(keccak, func(a, b []byte) int {
return bytes.Compare(a, b)
})
enc, err := json.Marshal(t.callstackWithOpcodes[0])
if err != nil {
return nil, err
}
return enc, t.reason
}
// Stop terminates execution of the tracer at the first opportune moment.
func (t *erc7562Tracer) Stop(err error) {
t.reason = err
t.interrupt.Store(true)
}
// clearFailedLogs clears the logs of a callframe and all its children
// in case of execution failure.
func (t *erc7562Tracer) clearFailedLogs(cf *callFrameWithOpcodes, parentFailed bool) {
failed := cf.failed() || parentFailed
// Clear own logs
if failed {
cf.Logs = nil
}
for i := range cf.Calls {
t.clearFailedLogs(&cf.Calls[i], failed)
}
}
func (t *erc7562Tracer) OnOpcode(pc uint64, op byte, gas, cost uint64, scope tracing.OpContext, rData []byte, depth int, err error) {
if t.interrupt.Load() {
return
}
var (
opcode = vm.OpCode(op)
opcodeWithStack *opcodeWithPartialStack
stackSize = len(scope.StackData())
stackLimit = min(stackSize, t.config.StackTopItemsSize)
stackTopItems = make([]uint256.Int, stackLimit)
)
for i := 0; i < stackLimit; i++ {
stackTopItems[i] = *peepStack(scope.StackData(), i)
}
opcodeWithStack = &opcodeWithPartialStack{
Opcode: opcode,
StackTopItems: stackTopItems,
}
t.handleReturnRevert(opcode)
size := len(t.callstackWithOpcodes)
currentCallFrame := &t.callstackWithOpcodes[size-1]
if t.lastOpWithStack != nil {
t.handleExtOpcodes(opcode, currentCallFrame)
}
t.handleAccessedContractSize(opcode, scope, currentCallFrame)
if t.lastOpWithStack != nil {
t.handleGasObserved(opcode, currentCallFrame)
}
t.storeUsedOpcode(opcode, currentCallFrame)
t.handleStorageAccess(opcode, scope, currentCallFrame)
t.storeKeccak(opcode, scope)
t.lastOpWithStack = opcodeWithStack
}
func (t *erc7562Tracer) handleReturnRevert(opcode vm.OpCode) {
if opcode == vm.REVERT || opcode == vm.RETURN {
t.lastOpWithStack = nil
}
}
func (t *erc7562Tracer) handleGasObserved(opcode vm.OpCode, currentCallFrame *callFrameWithOpcodes) {
// [OP-012]
pendingGasObserved := t.lastOpWithStack.Opcode == vm.GAS && !isCall(opcode)
if pendingGasObserved {
currentCallFrame.UsedOpcodes[vm.GAS]++
}
}
func (t *erc7562Tracer) storeUsedOpcode(opcode vm.OpCode, currentCallFrame *callFrameWithOpcodes) {
// ignore "unimportant" opcodes
if opcode != vm.GAS && !t.isIgnoredOpcode(opcode) {
currentCallFrame.UsedOpcodes[opcode]++
}
}
func (t *erc7562Tracer) handleStorageAccess(opcode vm.OpCode, scope tracing.OpContext, currentCallFrame *callFrameWithOpcodes) {
if opcode == vm.SLOAD || opcode == vm.SSTORE || opcode == vm.TLOAD || opcode == vm.TSTORE {
slot := common.BytesToHash(peepStack(scope.StackData(), 0).Bytes())
addr := scope.Address()
if opcode == vm.SLOAD {
// read slot values before this UserOp was created
// (so saving it if it was written before the first read)
_, rOk := currentCallFrame.AccessedSlots.Reads[slot]
_, wOk := currentCallFrame.AccessedSlots.Writes[slot]
if !rOk && !wOk {
currentCallFrame.AccessedSlots.Reads[slot] = append(currentCallFrame.AccessedSlots.Reads[slot], t.env.StateDB.GetState(addr, slot))
}
} else if opcode == vm.SSTORE {
currentCallFrame.AccessedSlots.Writes[slot]++
} else if opcode == vm.TLOAD {
currentCallFrame.AccessedSlots.TransientReads[slot]++
} else {
currentCallFrame.AccessedSlots.TransientWrites[slot]++
}
}
}
func (t *erc7562Tracer) storeKeccak(opcode vm.OpCode, scope tracing.OpContext) {
if opcode == vm.KECCAK256 {
dataOffset := peepStack(scope.StackData(), 0).Uint64()
dataLength := peepStack(scope.StackData(), 1).Uint64()
preimage, err := internal.GetMemoryCopyPadded(scope.MemoryData(), int64(dataOffset), int64(dataLength))
if err != nil {
log.Warn("erc7562Tracer: failed to copy keccak preimage from memory", "err", err)
return
}
t.keccakPreimages[string(preimage)] = struct{}{}
}
}
func (t *erc7562Tracer) handleExtOpcodes(opcode vm.OpCode, currentCallFrame *callFrameWithOpcodes) {
if isEXT(t.lastOpWithStack.Opcode) {
addr := common.HexToAddress(t.lastOpWithStack.StackTopItems[0].Hex())
// only store the last EXTCODE* opcode per address - could even be a boolean for our current use-case
// [OP-051]
if !(t.lastOpWithStack.Opcode == vm.EXTCODESIZE && opcode == vm.ISZERO) {
currentCallFrame.ExtCodeAccessInfo = append(currentCallFrame.ExtCodeAccessInfo, addr)
}
}
}
func (t *erc7562Tracer) handleAccessedContractSize(opcode vm.OpCode, scope tracing.OpContext, currentCallFrame *callFrameWithOpcodes) {
// [OP-041]
if isEXTorCALL(opcode) {
n := 0
if !isEXT(opcode) {
n = 1
}
addr := common.BytesToAddress(peepStack(scope.StackData(), n).Bytes())
if _, ok := currentCallFrame.ContractSize[addr]; !ok {
currentCallFrame.ContractSize[addr] = &contractSizeWithOpcode{
ContractSize: len(t.env.StateDB.GetCode(addr)),
Opcode: opcode,
}
}
}
}
func peepStack(stackData []uint256.Int, n int) *uint256.Int {
return &stackData[len(stackData)-n-1]
}
func isEXTorCALL(opcode vm.OpCode) bool {
return isEXT(opcode) || isCall(opcode)
}
func isEXT(opcode vm.OpCode) bool {
return opcode == vm.EXTCODEHASH ||
opcode == vm.EXTCODESIZE ||
opcode == vm.EXTCODECOPY
}
func isCall(opcode vm.OpCode) bool {
return opcode == vm.CALL ||
opcode == vm.CALLCODE ||
opcode == vm.DELEGATECALL ||
opcode == vm.STATICCALL
}
// Check if this opcode is ignored for the purposes of generating the used opcodes report
func (t *erc7562Tracer) isIgnoredOpcode(opcode vm.OpCode) bool {
if _, ok := t.ignoredOpcodes[opcode]; ok {
return true
}
return false
}
func defaultIgnoredOpcodes() []hexutil.Uint64 {
ignored := make([]hexutil.Uint64, 0, 64)
// Allow all PUSHx, DUPx and SWAPx opcodes as they have sequential codes
for op := vm.PUSH0; op <= vm.SWAP16; op++ {
ignored = append(ignored, hexutil.Uint64(op))
}
for _, op := range []vm.OpCode{
vm.POP, vm.ADD, vm.SUB, vm.MUL,
vm.DIV, vm.EQ, vm.LT, vm.GT,
vm.SLT, vm.SGT, vm.SHL, vm.SHR,
vm.AND, vm.OR, vm.NOT, vm.ISZERO,
} {
ignored = append(ignored, hexutil.Uint64(op))
}
return ignored
}