eth/tracers: add a golang tracer to locate contracts (#23708)

core/vm/opcodes.go

@@ -449,6 +449,7 @@ var stringToOp = map[string]OpCode{
 	"TIMESTAMP":      TIMESTAMP,
 	"NUMBER":         NUMBER,
 	"DIFFICULTY":     DIFFICULTY,
+	"PREVRANDAO":     PREVRANDAO,
 	"GASLIMIT":       GASLIMIT,
 	"SELFBALANCE":    SELFBALANCE,
 	"BASEFEE":        BASEFEE,

eth/tracers/native/contract.go

@@ -0,0 +1,120 @@
+// 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 native
+
+import (
+	"encoding/json"
+	"fmt"
+	"math/big"
+	"sync/atomic"
+	"time"
+
+	"github.com/XinFinOrg/XDPoSChain/common"
+	"github.com/XinFinOrg/XDPoSChain/core/vm"
+	"github.com/XinFinOrg/XDPoSChain/eth/tracers"
+)
+
+func init() {
+	tracers.RegisterNativeTracer("contractTracer", NewContractTracer)
+}
+
+type contractTracer struct {
+	Addrs     map[string]string
+	config    contractTracerConfig
+	interrupt uint32 // Atomic flag to signal execution interruption
+	reason    error  // Textual reason for the interruption
+}
+
+type contractTracerConfig struct {
+	OpCode string `json:"opCode"` // Target opcode to trace
+}
+
+// NewContractTracer returns a native go tracer which tracks the contracr was created
+func NewContractTracer(cfg json.RawMessage) (tracers.Tracer, error) {
+	var config contractTracerConfig
+	if cfg != nil {
+		if err := json.Unmarshal(cfg, &config); err != nil {
+			return nil, err
+		}
+	}
+	t := &contractTracer{
+		Addrs:  make(map[string]string, 1),
+		config: config,
+	}
+	// handle invalid opcode case
+	op := vm.StringToOp(t.config.OpCode)
+	if op == 0 && t.config.OpCode != "STOP" && t.config.OpCode != "" {
+		t.reason = fmt.Errorf("opcode %s not defined", t.config.OpCode)
+		return nil, t.reason
+	}
+	return t, nil
+}
+
+func (t *contractTracer) CaptureStart(env *vm.EVM, from common.Address, to common.Address, create bool, input []byte, gas uint64, value *big.Int) {
+	//When not searching for opcodes, record the contract address.
+	if create && t.config.OpCode == "" {
+		t.Addrs[addrToHex(to)] = ""
+	}
+}
+
+func (t *contractTracer) CaptureEnd(output []byte, gasUsed uint64, _ time.Duration, err error) {
+}
+
+func (t *contractTracer) CaptureState(env *vm.EVM, pc uint64, op vm.OpCode, gas, cost uint64, scope *vm.ScopeContext, rData []byte, depth int, err error) {
+	// Skip if tracing was interrupted
+	if atomic.LoadUint32(&t.interrupt) > 0 {
+		// TODO: env.Cancel()
+		return
+	}
+	// If the OpCode is empty , exit early.
+	if t.config.OpCode == "" {
+		return
+	}
+	targetOp := vm.StringToOp(t.config.OpCode)
+	if op == targetOp {
+		addr := scope.Contract.Address()
+		t.Addrs[addrToHex(addr)] = ""
+	}
+}
+
+func (t *contractTracer) CaptureFault(env *vm.EVM, pc uint64, op vm.OpCode, gas, cost uint64, _ *vm.ScopeContext, depth int, err error) {
+}
+
+func (t *contractTracer) CaptureEnter(typ vm.OpCode, from common.Address, to common.Address, input []byte, gas uint64, value *big.Int) {
+}
+
+func (t *contractTracer) CaptureExit(output []byte, gasUsed uint64, err error) {
+}
+
+func (t *contractTracer) GetResult() (json.RawMessage, error) {
+	// return Address array without duplicate address
+	AddrArray := make([]string, 0, len(t.Addrs))
+	for addr := range t.Addrs {
+		AddrArray = append(AddrArray, addr)
+	}
+
+	res, err := json.Marshal(AddrArray)
+	if err != nil {
+		return nil, err
+	}
+	return json.RawMessage(res), t.reason
+}
+
+func (t *contractTracer) Stop(err error) {
+	t.reason = err
+	atomic.StoreUint32(&t.interrupt, 1)
+}