diff options
Diffstat (limited to 'core/vm/vm.go')
-rw-r--r-- | core/vm/vm.go | 445 |
1 files changed, 82 insertions, 363 deletions
diff --git a/core/vm/vm.go b/core/vm/vm.go index 3521839df..56081f12c 100644 --- a/core/vm/vm.go +++ b/core/vm/vm.go @@ -19,6 +19,7 @@ package vm import ( "fmt" "math/big" + "sync/atomic" "time" "github.com/ethereum/go-ethereum/common" @@ -28,9 +29,9 @@ import ( "github.com/ethereum/go-ethereum/params" ) -// Config are the configuration options for the EVM +// Config are the configuration options for the Interpreter type Config struct { - // Debug enabled debugging EVM options + // Debug enabled debugging Interpreter options Debug bool // EnableJit enabled the JIT VM EnableJit bool @@ -38,40 +39,51 @@ type Config struct { ForceJit bool // Tracer is the op code logger Tracer Tracer - // NoRecursion disabled EVM call, callcode, + // NoRecursion disabled Interpreter call, callcode, // delegate call and create. NoRecursion bool + // Disable gas metering + DisableGasMetering bool + // JumpTable contains the EVM instruction table. This + // may me left uninitialised and will be set the default + // table. + JumpTable [256]operation } -// EVM is used to run Ethereum based contracts and will utilise the +// Interpreter is used to run Ethereum based contracts and will utilise the // passed environment to query external sources for state information. -// The EVM will run the byte code VM or JIT VM based on the passed +// The Interpreter will run the byte code VM or JIT VM based on the passed // configuration. -type EVM struct { - env *Environment - jumpTable vmJumpTable - cfg Config - gasTable params.GasTable +type Interpreter struct { + env *EVM + cfg Config + gasTable params.GasTable } -// New returns a new instance of the EVM. -func New(env *Environment, cfg Config) *EVM { - return &EVM{ - env: env, - jumpTable: newJumpTable(env.ChainConfig(), env.BlockNumber), - cfg: cfg, - gasTable: env.ChainConfig().GasTable(env.BlockNumber), +// NewInterpreter returns a new instance of the Interpreter. +func NewInterpreter(env *EVM, cfg Config) *Interpreter { + // We use the STOP instruction whether to see + // the jump table was initialised. If it was not + // we'll set the default jump table. + if !cfg.JumpTable[STOP].valid { + cfg.JumpTable = defaultJumpTable + } + + return &Interpreter{ + env: env, + cfg: cfg, + gasTable: env.ChainConfig().GasTable(env.BlockNumber), } } // Run loops and evaluates the contract's code with the given input data -func (evm *EVM) Run(contract *Contract, input []byte) (ret []byte, err error) { - evm.env.Depth++ - defer func() { evm.env.Depth-- }() +func (evm *Interpreter) Run(contract *Contract, input []byte) (ret []byte, err error) { + evm.env.depth++ + defer func() { evm.env.depth-- }() if contract.CodeAddr != nil { - if p := Precompiled[contract.CodeAddr.Str()]; p != nil { - return evm.RunPrecompiled(p, input, contract) + if p := PrecompiledContracts[*contract.CodeAddr]; p != nil { + return RunPrecompiledContract(p, input, contract) } } @@ -84,384 +96,91 @@ func (evm *EVM) Run(contract *Contract, input []byte) (ret []byte, err error) { if codehash == (common.Hash{}) { codehash = crypto.Keccak256Hash(contract.Code) } - var program *Program - if false { - // JIT disabled due to JIT not being Homestead gas reprice ready. - - // If the JIT is enabled check the status of the JIT program, - // if it doesn't exist compile a new program in a separate - // goroutine or wait for compilation to finish if the JIT is - // forced. - switch GetProgramStatus(codehash) { - case progReady: - return RunProgram(GetProgram(codehash), evm.env, contract, input) - case progUnknown: - if evm.cfg.ForceJit { - // Create and compile program - program = NewProgram(contract.Code) - perr := CompileProgram(program) - if perr == nil { - return RunProgram(program, evm.env, contract, input) - } - glog.V(logger.Info).Infoln("error compiling program", err) - } else { - // create and compile the program. Compilation - // is done in a separate goroutine - program = NewProgram(contract.Code) - go func() { - err := CompileProgram(program) - if err != nil { - glog.V(logger.Info).Infoln("error compiling program", err) - return - } - }() - } - } - } var ( - caller = contract.caller - code = contract.Code - instrCount = 0 - op OpCode // current opcode mem = NewMemory() // bound memory stack = newstack() // local stack // For optimisation reason we're using uint64 as the program counter. // It's theoretically possible to go above 2^64. The YP defines the PC to be uint256. Practically much less so feasible. - pc = uint64(0) // program counter - - // jump evaluates and checks whether the given jump destination is a valid one - // if valid move the `pc` otherwise return an error. - jump = func(from uint64, to *big.Int) error { - if !contract.jumpdests.has(codehash, code, to) { - nop := contract.GetOp(to.Uint64()) - return fmt.Errorf("invalid jump destination (%v) %v", nop, to) - } - - pc = to.Uint64() - - return nil - } - - newMemSize *big.Int - cost *big.Int + pc = uint64(0) // program counter + cost *big.Int ) contract.Input = input // User defer pattern to check for an error and, based on the error being nil or not, use all gas and return. defer func() { if err != nil && evm.cfg.Debug { - evm.cfg.Tracer.CaptureState(evm.env, pc, op, contract.Gas, cost, mem, stack, contract, evm.env.Depth, err) + evm.cfg.Tracer.CaptureState(evm.env, pc, op, contract.Gas, cost, mem, stack, contract, evm.env.depth, err) } }() if glog.V(logger.Debug) { - glog.Infof("running byte VM %x\n", codehash[:4]) + glog.Infof("evm running: %x\n", codehash[:4]) tstart := time.Now() defer func() { - glog.Infof("byte VM %x done. time: %v instrc: %v\n", codehash[:4], time.Since(tstart), instrCount) + glog.Infof("evm done: %x. time: %v\n", codehash[:4], time.Since(tstart)) }() } - for ; ; instrCount++ { - /* - if EnableJit && it%100 == 0 { - if program != nil && progStatus(atomic.LoadInt32(&program.status)) == progReady { - // move execution - fmt.Println("moved", it) - glog.V(logger.Info).Infoln("Moved execution to JIT") - return runProgram(program, pc, mem, stack, evm.env, contract, input) - } - } - */ - + // The Interpreter main run loop (contextual). This loop runs until either an + // explicit STOP, RETURN or SUICIDE is executed, an error accured during + // the execution of one of the operations or until the evm.done is set by + // the parent context.Context. + for atomic.LoadInt32(&evm.env.abort) == 0 { // Get the memory location of pc op = contract.GetOp(pc) - //fmt.Printf("OP %d %v\n", op, op) - // calculate the new memory size and gas price for the current executing opcode - newMemSize, cost, err = calculateGasAndSize(evm.gasTable, evm.env, contract, caller, op, mem, stack) - if err != nil { - return nil, err - } - // Use the calculated gas. When insufficient gas is present, use all gas and return an - // Out Of Gas error - if !contract.UseGas(cost) { - return nil, OutOfGasError - } + // get the operation from the jump table matching the opcode + operation := evm.cfg.JumpTable[op] - // Resize the memory calculated previously - mem.Resize(newMemSize.Uint64()) - // Add a log message - if evm.cfg.Debug { - err = evm.cfg.Tracer.CaptureState(evm.env, pc, op, contract.Gas, cost, mem, stack, contract, evm.env.Depth, nil) - if err != nil { - return nil, err - } + // if the op is invalid abort the process and return an error + if !operation.valid { + return nil, fmt.Errorf("invalid opcode %x", op) } - if opPtr := evm.jumpTable[op]; opPtr.valid { - if opPtr.fn != nil { - opPtr.fn(instruction{}, &pc, evm.env, contract, mem, stack) - } else { - switch op { - case PC: - opPc(instruction{data: new(big.Int).SetUint64(pc)}, &pc, evm.env, contract, mem, stack) - case JUMP: - if err := jump(pc, stack.pop()); err != nil { - return nil, err - } - - continue - case JUMPI: - pos, cond := stack.pop(), stack.pop() - - if cond.Cmp(common.BigTrue) >= 0 { - if err := jump(pc, pos); err != nil { - return nil, err - } - - continue - } - case RETURN: - offset, size := stack.pop(), stack.pop() - ret := mem.GetPtr(offset.Int64(), size.Int64()) - - return ret, nil - case SUICIDE: - opSuicide(instruction{}, nil, evm.env, contract, mem, stack) - - fallthrough - case STOP: // Stop the contract - return nil, nil - } - } - } else { - return nil, fmt.Errorf("Invalid opcode %x", op) + // validate the stack and make sure there enough stack items available + // to perform the operation + if err := operation.validateStack(stack); err != nil { + return nil, err } - pc++ - - } -} - -// calculateGasAndSize calculates the required given the opcode and stack items calculates the new memorysize for -// the operation. This does not reduce gas or resizes the memory. -func calculateGasAndSize(gasTable params.GasTable, env *Environment, contract *Contract, caller ContractRef, op OpCode, mem *Memory, stack *Stack) (*big.Int, *big.Int, error) { - var ( - gas = new(big.Int) - newMemSize *big.Int = new(big.Int) - ) - err := baseCheck(op, stack, gas) - if err != nil { - return nil, nil, err - } - - // stack Check, memory resize & gas phase - switch op { - case SUICIDE: - // EIP150 homestead gas reprice fork: - if gasTable.CreateBySuicide != nil { - gas.Set(gasTable.Suicide) - var ( - address = common.BigToAddress(stack.data[len(stack.data)-1]) - eip158 = env.ChainConfig().IsEIP158(env.BlockNumber) - ) - - if eip158 { - // if empty and transfers value - if env.StateDB.Empty(address) && env.StateDB.GetBalance(contract.Address()).BitLen() > 0 { - gas.Add(gas, gasTable.CreateBySuicide) - } - } else if !env.StateDB.Exist(address) { - gas.Add(gas, gasTable.CreateBySuicide) - } + var memorySize *big.Int + // calculate the new memory size and expand the memory to fit + // the operation + if operation.memorySize != nil { + memorySize = operation.memorySize(stack) + // memory is expanded in words of 32 bytes. Gas + // is also calculated in words. + memorySize.Mul(toWordSize(memorySize), big.NewInt(32)) } - if !env.StateDB.HasSuicided(contract.Address()) { - env.StateDB.AddRefund(params.SuicideRefundGas) - } - case EXTCODESIZE: - gas.Set(gasTable.ExtcodeSize) - case BALANCE: - gas.Set(gasTable.Balance) - case SLOAD: - gas.Set(gasTable.SLoad) - case SWAP1, SWAP2, SWAP3, SWAP4, SWAP5, SWAP6, SWAP7, SWAP8, SWAP9, SWAP10, SWAP11, SWAP12, SWAP13, SWAP14, SWAP15, SWAP16: - n := int(op - SWAP1 + 2) - err := stack.require(n) - if err != nil { - return nil, nil, err - } - gas.Set(GasFastestStep) - case DUP1, DUP2, DUP3, DUP4, DUP5, DUP6, DUP7, DUP8, DUP9, DUP10, DUP11, DUP12, DUP13, DUP14, DUP15, DUP16: - n := int(op - DUP1 + 1) - err := stack.require(n) - if err != nil { - return nil, nil, err - } - gas.Set(GasFastestStep) - case LOG0, LOG1, LOG2, LOG3, LOG4: - n := int(op - LOG0) - err := stack.require(n + 2) - if err != nil { - return nil, nil, err + if !evm.cfg.DisableGasMetering { + // consume the gas and return an error if not enough gas is available. + // cost is explicitly set so that the capture state defer method cas get the proper cost + cost = operation.gasCost(evm.gasTable, evm.env, contract, stack, mem, memorySize) + if !contract.UseGas(cost) { + return nil, ErrOutOfGas + } } - - mSize, mStart := stack.data[stack.len()-2], stack.data[stack.len()-1] - - gas.Add(gas, params.LogGas) - gas.Add(gas, new(big.Int).Mul(big.NewInt(int64(n)), params.LogTopicGas)) - gas.Add(gas, new(big.Int).Mul(mSize, params.LogDataGas)) - - newMemSize = calcMemSize(mStart, mSize) - - quadMemGas(mem, newMemSize, gas) - case EXP: - expByteLen := int64((stack.data[stack.len()-2].BitLen() + 7) / 8) - gas.Add(gas, new(big.Int).Mul(big.NewInt(expByteLen), gasTable.ExpByte)) - case SSTORE: - err := stack.require(2) - if err != nil { - return nil, nil, err + if memorySize != nil { + mem.Resize(memorySize.Uint64()) } - var g *big.Int - y, x := stack.data[stack.len()-2], stack.data[stack.len()-1] - val := env.StateDB.GetState(contract.Address(), common.BigToHash(x)) - - // This checks for 3 scenario's and calculates gas accordingly - // 1. From a zero-value address to a non-zero value (NEW VALUE) - // 2. From a non-zero value address to a zero-value address (DELETE) - // 3. From a non-zero to a non-zero (CHANGE) - if common.EmptyHash(val) && !common.EmptyHash(common.BigToHash(y)) { - // 0 => non 0 - g = params.SstoreSetGas - } else if !common.EmptyHash(val) && common.EmptyHash(common.BigToHash(y)) { - env.StateDB.AddRefund(params.SstoreRefundGas) - - g = params.SstoreClearGas - } else { - // non 0 => non 0 (or 0 => 0) - g = params.SstoreResetGas + if evm.cfg.Debug { + evm.cfg.Tracer.CaptureState(evm.env, pc, op, contract.Gas, cost, mem, stack, contract, evm.env.depth, err) } - gas.Set(g) - case MLOAD: - newMemSize = calcMemSize(stack.peek(), u256(32)) - quadMemGas(mem, newMemSize, gas) - case MSTORE8: - newMemSize = calcMemSize(stack.peek(), u256(1)) - quadMemGas(mem, newMemSize, gas) - case MSTORE: - newMemSize = calcMemSize(stack.peek(), u256(32)) - quadMemGas(mem, newMemSize, gas) - case RETURN: - newMemSize = calcMemSize(stack.peek(), stack.data[stack.len()-2]) - quadMemGas(mem, newMemSize, gas) - case SHA3: - newMemSize = calcMemSize(stack.peek(), stack.data[stack.len()-2]) - - words := toWordSize(stack.data[stack.len()-2]) - gas.Add(gas, words.Mul(words, params.Sha3WordGas)) - - quadMemGas(mem, newMemSize, gas) - case CALLDATACOPY: - newMemSize = calcMemSize(stack.peek(), stack.data[stack.len()-3]) - - words := toWordSize(stack.data[stack.len()-3]) - gas.Add(gas, words.Mul(words, params.CopyGas)) - - quadMemGas(mem, newMemSize, gas) - case CODECOPY: - newMemSize = calcMemSize(stack.peek(), stack.data[stack.len()-3]) - - words := toWordSize(stack.data[stack.len()-3]) - gas.Add(gas, words.Mul(words, params.CopyGas)) - - quadMemGas(mem, newMemSize, gas) - case EXTCODECOPY: - gas.Set(gasTable.ExtcodeCopy) - - newMemSize = calcMemSize(stack.data[stack.len()-2], stack.data[stack.len()-4]) - - words := toWordSize(stack.data[stack.len()-4]) - gas.Add(gas, words.Mul(words, params.CopyGas)) - - quadMemGas(mem, newMemSize, gas) - case CREATE: - newMemSize = calcMemSize(stack.data[stack.len()-2], stack.data[stack.len()-3]) - quadMemGas(mem, newMemSize, gas) - case CALL, CALLCODE: - gas.Set(gasTable.Calls) - - transfersValue := stack.data[len(stack.data)-3].BitLen() > 0 - if op == CALL { - var ( - address = common.BigToAddress(stack.data[len(stack.data)-2]) - eip158 = env.ChainConfig().IsEIP158(env.BlockNumber) - ) - if eip158 { - if env.StateDB.Empty(address) && transfersValue { - gas.Add(gas, params.CallNewAccountGas) - } - } else if !env.StateDB.Exist(address) { - gas.Add(gas, params.CallNewAccountGas) - } - } - if transfersValue { - gas.Add(gas, params.CallValueTransferGas) + // execute the operation + res, err := operation.execute(&pc, evm.env, contract, mem, stack) + switch { + case err != nil: + return nil, err + case operation.halts: + return res, nil + case !operation.jumps: + pc++ } - x := calcMemSize(stack.data[stack.len()-6], stack.data[stack.len()-7]) - y := calcMemSize(stack.data[stack.len()-4], stack.data[stack.len()-5]) - - newMemSize = common.BigMax(x, y) - - quadMemGas(mem, newMemSize, gas) - - cg := callGas(gasTable, contract.Gas, gas, stack.data[stack.len()-1]) - // Replace the stack item with the new gas calculation. This means that - // either the original item is left on the stack or the item is replaced by: - // (availableGas - gas) * 63 / 64 - // We replace the stack item so that it's available when the opCall instruction is - // called. This information is otherwise lost due to the dependency on *current* - // available gas. - stack.data[stack.len()-1] = cg - gas.Add(gas, cg) - - case DELEGATECALL: - gas.Set(gasTable.Calls) - - x := calcMemSize(stack.data[stack.len()-5], stack.data[stack.len()-6]) - y := calcMemSize(stack.data[stack.len()-3], stack.data[stack.len()-4]) - - newMemSize = common.BigMax(x, y) - - quadMemGas(mem, newMemSize, gas) - - cg := callGas(gasTable, contract.Gas, gas, stack.data[stack.len()-1]) - // Replace the stack item with the new gas calculation. This means that - // either the original item is left on the stack or the item is replaced by: - // (availableGas - gas) * 63 / 64 - // We replace the stack item so that it's available when the opCall instruction is - // called. - stack.data[stack.len()-1] = cg - gas.Add(gas, cg) - - } - - return newMemSize, gas, nil -} - -// RunPrecompile runs and evaluate the output of a precompiled contract defined in contracts.go -func (evm *EVM) RunPrecompiled(p *PrecompiledAccount, input []byte, contract *Contract) (ret []byte, err error) { - gas := p.Gas(len(input)) - if contract.UseGas(gas) { - ret = p.Call(input) - - return ret, nil - } else { - return nil, OutOfGasError } + return nil, nil } |