Merge pull request ethereum#1964 from obscuren/evm-runtime

core/vm/runtime: added simple execution runtime

core/vm/runtime/doc.go

@@ -0,0 +1,18 @@
+// Copyright 2014 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 runtime provides a basic execution model for executing EVM code.
+package runtime

core/vm/runtime/env.go

@@ -0,0 +1,106 @@
+// Copyright 2014 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 runtime
+
+import (
+	"math/big"
+
+	"github.com/ethereum/go-ethereum/common"
+	"github.com/ethereum/go-ethereum/core"
+	"github.com/ethereum/go-ethereum/core/state"
+	"github.com/ethereum/go-ethereum/core/vm"
+)
+
+// Env is a basic runtime environment required for running the EVM.
+type Env struct {
+	depth int
+	state *state.StateDB
+
+	origin   common.Address
+	coinbase common.Address
+
+	number     *big.Int
+	time       *big.Int
+	difficulty *big.Int
+	gasLimit   *big.Int
+
+	logs []vm.StructLog
+
+	getHashFn func(uint64) common.Hash
+}
+
+// NewEnv returns a new vm.Environment
+func NewEnv(cfg *Config, state *state.StateDB) vm.Environment {
+	return &Env{
+		state:      state,
+		origin:     cfg.Origin,
+		coinbase:   cfg.Coinbase,
+		number:     cfg.BlockNumber,
+		time:       cfg.Time,
+		difficulty: cfg.Difficulty,
+		gasLimit:   cfg.GasLimit,
+	}
+}
+
+func (self *Env) StructLogs() []vm.StructLog {
+	return self.logs
+}
+
+func (self *Env) AddStructLog(log vm.StructLog) {
+	self.logs = append(self.logs, log)
+}
+
+func (self *Env) Origin() common.Address   { return self.origin }
+func (self *Env) BlockNumber() *big.Int    { return self.number }
+func (self *Env) Coinbase() common.Address { return self.coinbase }
+func (self *Env) Time() *big.Int           { return self.time }
+func (self *Env) Difficulty() *big.Int     { return self.difficulty }
+func (self *Env) Db() vm.Database          { return self.state }
+func (self *Env) GasLimit() *big.Int       { return self.gasLimit }
+func (self *Env) VmType() vm.Type          { return vm.StdVmTy }
+func (self *Env) GetHash(n uint64) common.Hash {
+	return self.getHashFn(n)
+}
+func (self *Env) AddLog(log *vm.Log) {
+	self.state.AddLog(log)
+}
+func (self *Env) Depth() int     { return self.depth }
+func (self *Env) SetDepth(i int) { self.depth = i }
+func (self *Env) CanTransfer(from common.Address, balance *big.Int) bool {
+	return self.state.GetBalance(from).Cmp(balance) >= 0
+}
+func (self *Env) MakeSnapshot() vm.Database {
+	return self.state.Copy()
+}
+func (self *Env) SetSnapshot(copy vm.Database) {
+	self.state.Set(copy.(*state.StateDB))
+}
+
+func (self *Env) Transfer(from, to vm.Account, amount *big.Int) {
+	core.Transfer(from, to, amount)
+}
+
+func (self *Env) Call(caller vm.ContractRef, addr common.Address, data []byte, gas, price, value *big.Int) ([]byte, error) {
+	return core.Call(self, caller, addr, data, gas, price, value)
+}
+func (self *Env) CallCode(caller vm.ContractRef, addr common.Address, data []byte, gas, price, value *big.Int) ([]byte, error) {
+	return core.CallCode(self, caller, addr, data, gas, price, value)
+}
+
+func (self *Env) Create(caller vm.ContractRef, data []byte, gas, price, value *big.Int) ([]byte, common.Address, error) {
+	return core.Create(self, caller, data, gas, price, value)
+}

core/vm/runtime/runtime.go

@@ -0,0 +1,121 @@
+// Copyright 2014 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 runtime
+
+import (
+	"math/big"
+	"time"
+
+	"github.com/ethereum/go-ethereum/common"
+	"github.com/ethereum/go-ethereum/core/state"
+	"github.com/ethereum/go-ethereum/core/vm"
+	"github.com/ethereum/go-ethereum/crypto"
+	"github.com/ethereum/go-ethereum/ethdb"
+)
+
+// Config is a basic type specifing certain configuration flags for running
+// the EVM.
+type Config struct {
+	Difficulty  *big.Int
+	Origin      common.Address
+	Coinbase    common.Address
+	BlockNumber *big.Int
+	Time        *big.Int
+	GasLimit    *big.Int
+	GasPrice    *big.Int
+	Value       *big.Int
+	DisableJit  bool // "disable" so it's enabled by default
+	Debug       bool
+
+	GetHashFn func(n uint64) common.Hash
+}
+
+// sets defaults on the config
+func setDefaults(cfg *Config) {
+	if cfg.Difficulty == nil {
+		cfg.Difficulty = new(big.Int)
+	}
+	if cfg.Time == nil {
+		cfg.Time = big.NewInt(time.Now().Unix())
+	}
+	if cfg.GasLimit == nil {
+		cfg.GasLimit = new(big.Int).Set(common.MaxBig)
+	}
+	if cfg.GasPrice == nil {
+		cfg.GasPrice = new(big.Int)
+	}
+	if cfg.Value == nil {
+		cfg.Value = new(big.Int)
+	}
+	if cfg.BlockNumber == nil {
+		cfg.BlockNumber = new(big.Int)
+	}
+	if cfg.GetHashFn == nil {
+		cfg.GetHashFn = func(n uint64) common.Hash {
+			return common.BytesToHash(crypto.Sha3([]byte(new(big.Int).SetUint64(n).String())))
+		}
+	}
+}
+
+// Execute executes the code using the input as call data during the execution.
+// It returns the EVM's return value, the new state and an error if it failed.
+//
+// Executes sets up a in memory, temporarily, environment for the execution of
+// the given code. It enabled the JIT by default and make sure that it's restored
+// to it's original state afterwards.
+func Execute(code, input []byte, cfg *Config) ([]byte, *state.StateDB, error) {
+	if cfg == nil {
+		cfg = new(Config)
+	}
+	setDefaults(cfg)
+
+	// defer the call to setting back the original values
+	defer func(debug, forceJit, enableJit bool) {
+		vm.Debug = debug
+		vm.ForceJit = forceJit
+		vm.EnableJit = enableJit
+	}(vm.Debug, vm.ForceJit, vm.EnableJit)
+
+	vm.ForceJit = !cfg.DisableJit
+	vm.EnableJit = !cfg.DisableJit
+	vm.Debug = cfg.Debug
+
+	var (
+		db, _      = ethdb.NewMemDatabase()
+		statedb, _ = state.New(common.Hash{}, db)
+		vmenv      = NewEnv(cfg, statedb)
+		sender     = statedb.CreateAccount(cfg.Origin)
+		receiver   = statedb.CreateAccount(common.StringToAddress("contract"))
+	)
+	// set the receiver's (the executing contract) code for execution.
+	receiver.SetCode(code)
+
+	// Call the code with the given configuration.
+	ret, err := vmenv.Call(
+		sender,
+		receiver.Address(),
+		input,
+		cfg.GasLimit,
+		cfg.GasPrice,
+		cfg.Value,
+	)
+
+	if cfg.Debug {
+		vm.StdErrFormat(vmenv.StructLogs())
+	}
+	return ret, statedb, err
+}

core/vm/runtime/runtime_example_test.go

@@ -0,0 +1,34 @@
+// 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 runtime_test
+
+import (
+	"fmt"
+
+	"github.com/ethereum/go-ethereum/common"
+	"github.com/ethereum/go-ethereum/core/vm/runtime"
+)
+
+func ExampleExecute() {
+	ret, _, err := runtime.Execute(common.Hex2Bytes("6060604052600a8060106000396000f360606040526008565b00"), nil, nil)
+	if err != nil {
+		fmt.Println(err)
+	}
+	fmt.Println(ret)
+	// Output:
+	// [96 96 96 64 82 96 8 86 91 0]
+}