474 lines
18 KiB
Go
474 lines
18 KiB
Go
// 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 vm
|
|
|
|
import (
|
|
"errors"
|
|
"math/big"
|
|
"sync/atomic"
|
|
"time"
|
|
|
|
"github.com/ethereum/go-ethereum/common"
|
|
"github.com/ethereum/go-ethereum/crypto"
|
|
"github.com/ethereum/go-ethereum/params"
|
|
)
|
|
|
|
// emptyCodeHash is used by create to ensure deployment is disallowed to already
|
|
// deployed contract addresses (relevant after the account abstraction).
|
|
var emptyCodeHash = crypto.Keccak256Hash(nil)
|
|
|
|
type (
|
|
// CanTransferFunc is the signature of a transfer guard function
|
|
CanTransferFunc func(StateDB, common.Address, *big.Int) bool
|
|
// TransferFunc is the signature of a transfer function
|
|
TransferFunc func(StateDB, common.Address, common.Address, *big.Int)
|
|
// GetHashFunc returns the n'th block hash in the blockchain
|
|
// and is used by the BLOCKHASH EVM op code.
|
|
GetHashFunc func(uint64) common.Hash
|
|
)
|
|
|
|
// run runs the given contract and takes care of running precompiles with a fallback to the byte code interpreter.
|
|
func run(evm *EVM, contract *Contract, input []byte, readOnly bool) ([]byte, error) {
|
|
if contract.CodeAddr != nil {
|
|
precompiles := PrecompiledContractsHomestead
|
|
if evm.chainRules.IsByzantium {
|
|
precompiles = PrecompiledContractsByzantium
|
|
}
|
|
if evm.chainRules.IsIstanbul {
|
|
precompiles = PrecompiledContractsIstanbul
|
|
}
|
|
if p := precompiles[*contract.CodeAddr]; p != nil {
|
|
return RunPrecompiledContract(p, input, contract)
|
|
}
|
|
}
|
|
for _, interpreter := range evm.interpreters {
|
|
if interpreter.CanRun(contract.Code) {
|
|
if evm.interpreter != interpreter {
|
|
// Ensure that the interpreter pointer is set back
|
|
// to its current value upon return.
|
|
defer func(i Interpreter) {
|
|
evm.interpreter = i
|
|
}(evm.interpreter)
|
|
evm.interpreter = interpreter
|
|
}
|
|
return interpreter.Run(contract, input, readOnly)
|
|
}
|
|
}
|
|
return nil, errors.New("no compatible interpreter")
|
|
}
|
|
|
|
// Context provides the EVM with auxiliary information. Once provided
|
|
// it shouldn't be modified.
|
|
type Context struct {
|
|
// CanTransfer returns whether the account contains
|
|
// sufficient ether to transfer the value
|
|
CanTransfer CanTransferFunc
|
|
// Transfer transfers ether from one account to the other
|
|
Transfer TransferFunc
|
|
// GetHash returns the hash corresponding to n
|
|
GetHash GetHashFunc
|
|
|
|
// Message information
|
|
Origin common.Address // Provides information for ORIGIN
|
|
GasPrice *big.Int // Provides information for GASPRICE
|
|
|
|
// Block information
|
|
Coinbase common.Address // Provides information for COINBASE
|
|
GasLimit uint64 // Provides information for GASLIMIT
|
|
BlockNumber *big.Int // Provides information for NUMBER
|
|
Time *big.Int // Provides information for TIME
|
|
Difficulty *big.Int // Provides information for DIFFICULTY
|
|
}
|
|
|
|
// EVM is the Ethereum Virtual Machine base object and provides
|
|
// the necessary tools to run a contract on the given state with
|
|
// the provided context. It should be noted that any error
|
|
// generated through any of the calls should be considered a
|
|
// revert-state-and-consume-all-gas operation, no checks on
|
|
// specific errors should ever be performed. The interpreter makes
|
|
// sure that any errors generated are to be considered faulty code.
|
|
//
|
|
// The EVM should never be reused and is not thread safe.
|
|
type EVM struct {
|
|
// Context provides auxiliary blockchain related information
|
|
Context
|
|
// StateDB gives access to the underlying state
|
|
StateDB StateDB
|
|
// Depth is the current call stack
|
|
depth int
|
|
|
|
// chainConfig contains information about the current chain
|
|
chainConfig *params.ChainConfig
|
|
// chain rules contains the chain rules for the current epoch
|
|
chainRules params.Rules
|
|
// virtual machine configuration options used to initialise the
|
|
// evm.
|
|
vmConfig Config
|
|
// global (to this context) ethereum virtual machine
|
|
// used throughout the execution of the tx.
|
|
interpreters []Interpreter
|
|
interpreter Interpreter
|
|
// abort is used to abort the EVM calling operations
|
|
// NOTE: must be set atomically
|
|
abort int32
|
|
// callGasTemp holds the gas available for the current call. This is needed because the
|
|
// available gas is calculated in gasCall* according to the 63/64 rule and later
|
|
// applied in opCall*.
|
|
callGasTemp uint64
|
|
}
|
|
|
|
// NewEVM returns a new EVM. The returned EVM is not thread safe and should
|
|
// only ever be used *once*.
|
|
func NewEVM(ctx Context, statedb StateDB, chainConfig *params.ChainConfig, vmConfig Config) *EVM {
|
|
evm := &EVM{
|
|
Context: ctx,
|
|
StateDB: statedb,
|
|
vmConfig: vmConfig,
|
|
chainConfig: chainConfig,
|
|
chainRules: chainConfig.Rules(ctx.BlockNumber),
|
|
interpreters: make([]Interpreter, 0, 1),
|
|
}
|
|
|
|
if chainConfig.IsEWASM(ctx.BlockNumber) {
|
|
// to be implemented by EVM-C and Wagon PRs.
|
|
// if vmConfig.EWASMInterpreter != "" {
|
|
// extIntOpts := strings.Split(vmConfig.EWASMInterpreter, ":")
|
|
// path := extIntOpts[0]
|
|
// options := []string{}
|
|
// if len(extIntOpts) > 1 {
|
|
// options = extIntOpts[1..]
|
|
// }
|
|
// evm.interpreters = append(evm.interpreters, NewEVMVCInterpreter(evm, vmConfig, options))
|
|
// } else {
|
|
// evm.interpreters = append(evm.interpreters, NewEWASMInterpreter(evm, vmConfig))
|
|
// }
|
|
panic("No supported ewasm interpreter yet.")
|
|
}
|
|
|
|
// vmConfig.EVMInterpreter will be used by EVM-C, it won't be checked here
|
|
// as we always want to have the built-in EVM as the failover option.
|
|
evm.interpreters = append(evm.interpreters, NewEVMInterpreter(evm, vmConfig))
|
|
evm.interpreter = evm.interpreters[0]
|
|
|
|
return evm
|
|
}
|
|
|
|
// Cancel cancels any running EVM operation. This may be called concurrently and
|
|
// it's safe to be called multiple times.
|
|
func (evm *EVM) Cancel() {
|
|
atomic.StoreInt32(&evm.abort, 1)
|
|
}
|
|
|
|
// Cancelled returns true if Cancel has been called
|
|
func (evm *EVM) Cancelled() bool {
|
|
return atomic.LoadInt32(&evm.abort) == 1
|
|
}
|
|
|
|
// Interpreter returns the current interpreter
|
|
func (evm *EVM) Interpreter() Interpreter {
|
|
return evm.interpreter
|
|
}
|
|
|
|
// Call executes the contract associated with the addr with the given input as
|
|
// parameters. It also handles any necessary value transfer required and takes
|
|
// the necessary steps to create accounts and reverses the state in case of an
|
|
// execution error or failed value transfer.
|
|
func (evm *EVM) Call(caller ContractRef, addr common.Address, input []byte, gas uint64, value *big.Int) (ret []byte, leftOverGas uint64, err error) {
|
|
if evm.vmConfig.NoRecursion && evm.depth > 0 {
|
|
return nil, gas, nil
|
|
}
|
|
// Fail if we're trying to execute above the call depth limit
|
|
if evm.depth > int(params.CallCreateDepth) {
|
|
return nil, gas, ErrDepth
|
|
}
|
|
// Fail if we're trying to transfer more than the available balance
|
|
if !evm.Context.CanTransfer(evm.StateDB, caller.Address(), value) {
|
|
return nil, gas, ErrInsufficientBalance
|
|
}
|
|
var (
|
|
to = AccountRef(addr)
|
|
snapshot = evm.StateDB.Snapshot()
|
|
)
|
|
if !evm.StateDB.Exist(addr) {
|
|
precompiles := PrecompiledContractsHomestead
|
|
if evm.chainRules.IsByzantium {
|
|
precompiles = PrecompiledContractsByzantium
|
|
}
|
|
if evm.chainRules.IsIstanbul {
|
|
precompiles = PrecompiledContractsIstanbul
|
|
}
|
|
if precompiles[addr] == nil && evm.chainRules.IsEIP158 && value.Sign() == 0 {
|
|
// Calling a non existing account, don't do anything, but ping the tracer
|
|
if evm.vmConfig.Debug && evm.depth == 0 {
|
|
evm.vmConfig.Tracer.CaptureStart(caller.Address(), addr, false, input, gas, value)
|
|
evm.vmConfig.Tracer.CaptureEnd(ret, 0, 0, nil)
|
|
}
|
|
return nil, gas, nil
|
|
}
|
|
evm.StateDB.CreateAccount(addr)
|
|
}
|
|
evm.Transfer(evm.StateDB, caller.Address(), to.Address(), value)
|
|
// Initialise a new contract and set the code that is to be used by the EVM.
|
|
// The contract is a scoped environment for this execution context only.
|
|
contract := NewContract(caller, to, value, gas)
|
|
contract.SetCallCode(&addr, evm.StateDB.GetCodeHash(addr), evm.StateDB.GetCode(addr))
|
|
|
|
// Even if the account has no code, we need to continue because it might be a precompile
|
|
start := time.Now()
|
|
|
|
// Capture the tracer start/end events in debug mode
|
|
if evm.vmConfig.Debug && evm.depth == 0 {
|
|
evm.vmConfig.Tracer.CaptureStart(caller.Address(), addr, false, input, gas, value)
|
|
|
|
defer func() { // Lazy evaluation of the parameters
|
|
evm.vmConfig.Tracer.CaptureEnd(ret, gas-contract.Gas, time.Since(start), err)
|
|
}()
|
|
}
|
|
ret, err = run(evm, contract, input, false)
|
|
|
|
// When an error was returned by the EVM or when setting the creation code
|
|
// above we revert to the snapshot and consume any gas remaining. Additionally
|
|
// when we're in homestead this also counts for code storage gas errors.
|
|
if err != nil {
|
|
evm.StateDB.RevertToSnapshot(snapshot)
|
|
if err != ErrExecutionReverted {
|
|
contract.UseGas(contract.Gas)
|
|
}
|
|
}
|
|
return ret, contract.Gas, err
|
|
}
|
|
|
|
// CallCode executes the contract associated with the addr with the given input
|
|
// as parameters. It also handles any necessary value transfer required and takes
|
|
// the necessary steps to create accounts and reverses the state in case of an
|
|
// execution error or failed value transfer.
|
|
//
|
|
// CallCode differs from Call in the sense that it executes the given address'
|
|
// code with the caller as context.
|
|
func (evm *EVM) CallCode(caller ContractRef, addr common.Address, input []byte, gas uint64, value *big.Int) (ret []byte, leftOverGas uint64, err error) {
|
|
if evm.vmConfig.NoRecursion && evm.depth > 0 {
|
|
return nil, gas, nil
|
|
}
|
|
// Fail if we're trying to execute above the call depth limit
|
|
if evm.depth > int(params.CallCreateDepth) {
|
|
return nil, gas, ErrDepth
|
|
}
|
|
// Fail if we're trying to transfer more than the available balance
|
|
// Note although it's noop to transfer X ether to caller itself. But
|
|
// if caller doesn't have enough balance, it would be an error to allow
|
|
// over-charging itself. So the check here is necessary.
|
|
if !evm.Context.CanTransfer(evm.StateDB, caller.Address(), value) {
|
|
return nil, gas, ErrInsufficientBalance
|
|
}
|
|
var (
|
|
snapshot = evm.StateDB.Snapshot()
|
|
to = AccountRef(caller.Address())
|
|
)
|
|
// Initialise a new contract and set the code that is to be used by the EVM.
|
|
// The contract is a scoped environment for this execution context only.
|
|
contract := NewContract(caller, to, value, gas)
|
|
contract.SetCallCode(&addr, evm.StateDB.GetCodeHash(addr), evm.StateDB.GetCode(addr))
|
|
|
|
ret, err = run(evm, contract, input, false)
|
|
if err != nil {
|
|
evm.StateDB.RevertToSnapshot(snapshot)
|
|
if err != ErrExecutionReverted {
|
|
contract.UseGas(contract.Gas)
|
|
}
|
|
}
|
|
return ret, contract.Gas, err
|
|
}
|
|
|
|
// DelegateCall executes the contract associated with the addr with the given input
|
|
// as parameters. It reverses the state in case of an execution error.
|
|
//
|
|
// DelegateCall differs from CallCode in the sense that it executes the given address'
|
|
// code with the caller as context and the caller is set to the caller of the caller.
|
|
func (evm *EVM) DelegateCall(caller ContractRef, addr common.Address, input []byte, gas uint64) (ret []byte, leftOverGas uint64, err error) {
|
|
if evm.vmConfig.NoRecursion && evm.depth > 0 {
|
|
return nil, gas, nil
|
|
}
|
|
// Fail if we're trying to execute above the call depth limit
|
|
if evm.depth > int(params.CallCreateDepth) {
|
|
return nil, gas, ErrDepth
|
|
}
|
|
var (
|
|
snapshot = evm.StateDB.Snapshot()
|
|
to = AccountRef(caller.Address())
|
|
)
|
|
// Initialise a new contract and make initialise the delegate values
|
|
contract := NewContract(caller, to, nil, gas).AsDelegate()
|
|
contract.SetCallCode(&addr, evm.StateDB.GetCodeHash(addr), evm.StateDB.GetCode(addr))
|
|
|
|
ret, err = run(evm, contract, input, false)
|
|
if err != nil {
|
|
evm.StateDB.RevertToSnapshot(snapshot)
|
|
if err != ErrExecutionReverted {
|
|
contract.UseGas(contract.Gas)
|
|
}
|
|
}
|
|
return ret, contract.Gas, err
|
|
}
|
|
|
|
// StaticCall executes the contract associated with the addr with the given input
|
|
// as parameters while disallowing any modifications to the state during the call.
|
|
// Opcodes that attempt to perform such modifications will result in exceptions
|
|
// instead of performing the modifications.
|
|
func (evm *EVM) StaticCall(caller ContractRef, addr common.Address, input []byte, gas uint64) (ret []byte, leftOverGas uint64, err error) {
|
|
if evm.vmConfig.NoRecursion && evm.depth > 0 {
|
|
return nil, gas, nil
|
|
}
|
|
// Fail if we're trying to execute above the call depth limit
|
|
if evm.depth > int(params.CallCreateDepth) {
|
|
return nil, gas, ErrDepth
|
|
}
|
|
var (
|
|
to = AccountRef(addr)
|
|
snapshot = evm.StateDB.Snapshot()
|
|
)
|
|
// Initialise a new contract and set the code that is to be used by the EVM.
|
|
// The contract is a scoped environment for this execution context only.
|
|
contract := NewContract(caller, to, new(big.Int), gas)
|
|
contract.SetCallCode(&addr, evm.StateDB.GetCodeHash(addr), evm.StateDB.GetCode(addr))
|
|
|
|
// We do an AddBalance of zero here, just in order to trigger a touch.
|
|
// This doesn't matter on Mainnet, where all empties are gone at the time of Byzantium,
|
|
// but is the correct thing to do and matters on other networks, in tests, and potential
|
|
// future scenarios
|
|
evm.StateDB.AddBalance(addr, bigZero)
|
|
|
|
// When an error was returned by the EVM or when setting the creation code
|
|
// above we revert to the snapshot and consume any gas remaining. Additionally
|
|
// when we're in Homestead this also counts for code storage gas errors.
|
|
ret, err = run(evm, contract, input, true)
|
|
if err != nil {
|
|
evm.StateDB.RevertToSnapshot(snapshot)
|
|
if err != ErrExecutionReverted {
|
|
contract.UseGas(contract.Gas)
|
|
}
|
|
}
|
|
return ret, contract.Gas, err
|
|
}
|
|
|
|
type codeAndHash struct {
|
|
code []byte
|
|
hash common.Hash
|
|
}
|
|
|
|
func (c *codeAndHash) Hash() common.Hash {
|
|
if c.hash == (common.Hash{}) {
|
|
c.hash = crypto.Keccak256Hash(c.code)
|
|
}
|
|
return c.hash
|
|
}
|
|
|
|
// create creates a new contract using code as deployment code.
|
|
func (evm *EVM) create(caller ContractRef, codeAndHash *codeAndHash, gas uint64, value *big.Int, address common.Address) ([]byte, common.Address, uint64, error) {
|
|
// Depth check execution. Fail if we're trying to execute above the
|
|
// limit.
|
|
if evm.depth > int(params.CallCreateDepth) {
|
|
return nil, common.Address{}, gas, ErrDepth
|
|
}
|
|
if !evm.CanTransfer(evm.StateDB, caller.Address(), value) {
|
|
return nil, common.Address{}, gas, ErrInsufficientBalance
|
|
}
|
|
nonce := evm.StateDB.GetNonce(caller.Address())
|
|
evm.StateDB.SetNonce(caller.Address(), nonce+1)
|
|
|
|
// Ensure there's no existing contract already at the designated address
|
|
contractHash := evm.StateDB.GetCodeHash(address)
|
|
if evm.StateDB.GetNonce(address) != 0 || (contractHash != (common.Hash{}) && contractHash != emptyCodeHash) {
|
|
return nil, common.Address{}, 0, ErrContractAddressCollision
|
|
}
|
|
// Create a new account on the state
|
|
snapshot := evm.StateDB.Snapshot()
|
|
evm.StateDB.CreateAccount(address)
|
|
if evm.chainRules.IsEIP158 {
|
|
evm.StateDB.SetNonce(address, 1)
|
|
}
|
|
evm.Transfer(evm.StateDB, caller.Address(), address, value)
|
|
|
|
// Initialise a new contract and set the code that is to be used by the EVM.
|
|
// The contract is a scoped environment for this execution context only.
|
|
contract := NewContract(caller, AccountRef(address), value, gas)
|
|
contract.SetCodeOptionalHash(&address, codeAndHash)
|
|
|
|
if evm.vmConfig.NoRecursion && evm.depth > 0 {
|
|
return nil, address, gas, nil
|
|
}
|
|
|
|
if evm.vmConfig.Debug && evm.depth == 0 {
|
|
evm.vmConfig.Tracer.CaptureStart(caller.Address(), address, true, codeAndHash.code, gas, value)
|
|
}
|
|
start := time.Now()
|
|
|
|
ret, err := run(evm, contract, nil, false)
|
|
|
|
// check whether the max code size has been exceeded
|
|
maxCodeSizeExceeded := evm.chainRules.IsEIP158 && len(ret) > params.MaxCodeSize
|
|
// if the contract creation ran successfully and no errors were returned
|
|
// calculate the gas required to store the code. If the code could not
|
|
// be stored due to not enough gas set an error and let it be handled
|
|
// by the error checking condition below.
|
|
if err == nil && !maxCodeSizeExceeded {
|
|
createDataGas := uint64(len(ret)) * params.CreateDataGas
|
|
if contract.UseGas(createDataGas) {
|
|
evm.StateDB.SetCode(address, ret)
|
|
} else {
|
|
err = ErrCodeStoreOutOfGas
|
|
}
|
|
}
|
|
|
|
// When an error was returned by the EVM or when setting the creation code
|
|
// above we revert to the snapshot and consume any gas remaining. Additionally
|
|
// when we're in homestead this also counts for code storage gas errors.
|
|
if maxCodeSizeExceeded || (err != nil && (evm.chainRules.IsHomestead || err != ErrCodeStoreOutOfGas)) {
|
|
evm.StateDB.RevertToSnapshot(snapshot)
|
|
if err != ErrExecutionReverted {
|
|
contract.UseGas(contract.Gas)
|
|
}
|
|
}
|
|
// Assign err if contract code size exceeds the max while the err is still empty.
|
|
if maxCodeSizeExceeded && err == nil {
|
|
err = ErrMaxCodeSizeExceeded
|
|
}
|
|
if evm.vmConfig.Debug && evm.depth == 0 {
|
|
evm.vmConfig.Tracer.CaptureEnd(ret, gas-contract.Gas, time.Since(start), err)
|
|
}
|
|
return ret, address, contract.Gas, err
|
|
|
|
}
|
|
|
|
// Create creates a new contract using code as deployment code.
|
|
func (evm *EVM) Create(caller ContractRef, code []byte, gas uint64, value *big.Int) (ret []byte, contractAddr common.Address, leftOverGas uint64, err error) {
|
|
contractAddr = crypto.CreateAddress(caller.Address(), evm.StateDB.GetNonce(caller.Address()))
|
|
return evm.create(caller, &codeAndHash{code: code}, gas, value, contractAddr)
|
|
}
|
|
|
|
// Create2 creates a new contract using code as deployment code.
|
|
//
|
|
// The different between Create2 with Create is Create2 uses sha3(0xff ++ msg.sender ++ salt ++ sha3(init_code))[12:]
|
|
// instead of the usual sender-and-nonce-hash as the address where the contract is initialized at.
|
|
func (evm *EVM) Create2(caller ContractRef, code []byte, gas uint64, endowment *big.Int, salt *big.Int) (ret []byte, contractAddr common.Address, leftOverGas uint64, err error) {
|
|
codeAndHash := &codeAndHash{code: code}
|
|
contractAddr = crypto.CreateAddress2(caller.Address(), common.BigToHash(salt), codeAndHash.Hash().Bytes())
|
|
return evm.create(caller, codeAndHash, gas, endowment, contractAddr)
|
|
}
|
|
|
|
// ChainConfig returns the environment's chain configuration
|
|
func (evm *EVM) ChainConfig() *params.ChainConfig { return evm.chainConfig }
|