package vm import ( "fmt" "math/big" "github.com/ethereum/go-ethereum/common" "github.com/ethereum/go-ethereum/core/state" "github.com/ethereum/go-ethereum/crypto" ) type Vm struct { env Environment logTy byte logStr string err error // For logging debug bool BreakPoints []int64 Stepping bool Fn string Recoverable bool // Will be called before the vm returns After func(*Context, error) } func New(env Environment) *Vm { lt := LogTyPretty return &Vm{debug: Debug, env: env, logTy: lt, Recoverable: true} } func (self *Vm) Run(context *Context, callData []byte) (ret []byte, err error) { self.env.SetDepth(self.env.Depth() + 1) defer self.env.SetDepth(self.env.Depth() - 1) var ( caller = context.caller code = context.Code value = context.value price = context.Price ) self.Printf("(%d) (%x) %x (code=%d) gas: %v (d) %x", self.env.Depth(), caller.Address().Bytes()[:4], context.Address(), len(code), context.Gas, callData).Endl() // 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 self.After != nil { self.After(context, err) } if err != nil { self.Printf(" %v", err).Endl() // In case of a VM exception (known exceptions) all gas consumed (panics NOT included). context.UseGas(context.Gas) ret = context.Return(nil) } }() if context.CodeAddr != nil { if p := Precompiled[context.CodeAddr.Str()]; p != nil { return self.RunPrecompiled(p, callData, context) } } var ( op OpCode destinations = analyseJumpDests(context.Code) mem = NewMemory() stack = newStack() pc = new(big.Int) statedb = self.env.State() jump = func(from *big.Int, to *big.Int) error { nop := context.GetOp(to) if !destinations.Has(to) { return fmt.Errorf("invalid jump destination (%v) %v", nop, to) } self.Printf(" ~> %v", to) pc = to self.Endl() return nil } ) // Don't bother with the execution if there's no code. if len(code) == 0 { return context.Return(nil), nil } for { // The base for all big integer arithmetic base := new(big.Int) // Get the memory location of pc op = context.GetOp(pc) self.Printf("(pc) %-3d -o- %-14s (m) %-4d (s) %-4d ", pc, op.String(), mem.Len(), stack.len()) newMemSize, gas, err := self.calculateGasAndSize(context, caller, op, statedb, mem, stack) if err != nil { return nil, err } self.Printf("(g) %-3v (%v)", gas, context.Gas) if !context.UseGas(gas) { self.Endl() tmp := new(big.Int).Set(context.Gas) context.UseGas(context.Gas) return context.Return(nil), OOG(gas, tmp) } mem.Resize(newMemSize.Uint64()) switch op { // 0x20 range case ADD: x, y := stack.pop(), stack.pop() self.Printf(" %v + %v", y, x) base.Add(x, y) U256(base) self.Printf(" = %v", base) // pop result back on the stack stack.push(base) case SUB: x, y := stack.pop(), stack.pop() self.Printf(" %v - %v", y, x) base.Sub(x, y) U256(base) self.Printf(" = %v", base) // pop result back on the stack stack.push(base) case MUL: x, y := stack.pop(), stack.pop() self.Printf(" %v * %v", y, x) base.Mul(x, y) U256(base) self.Printf(" = %v", base) // pop result back on the stack stack.push(base) case DIV: x, y := stack.pop(), stack.pop() self.Printf(" %v / %v", x, y) if y.Cmp(common.Big0) != 0 { base.Div(x, y) } U256(base) self.Printf(" = %v", base) // pop result back on the stack stack.push(base) case SDIV: x, y := S256(stack.pop()), S256(stack.pop()) self.Printf(" %v / %v", x, y) if y.Cmp(common.Big0) == 0 { base.Set(common.Big0) } else { n := new(big.Int) if new(big.Int).Mul(x, y).Cmp(common.Big0) < 0 { n.SetInt64(-1) } else { n.SetInt64(1) } base.Div(x.Abs(x), y.Abs(y)).Mul(base, n) U256(base) } self.Printf(" = %v", base) stack.push(base) case MOD: x, y := stack.pop(), stack.pop() self.Printf(" %v %% %v", x, y) if y.Cmp(common.Big0) == 0 { base.Set(common.Big0) } else { base.Mod(x, y) } U256(base) self.Printf(" = %v", base) stack.push(base) case SMOD: x, y := S256(stack.pop()), S256(stack.pop()) self.Printf(" %v %% %v", x, y) if y.Cmp(common.Big0) == 0 { base.Set(common.Big0) } else { n := new(big.Int) if x.Cmp(common.Big0) < 0 { n.SetInt64(-1) } else { n.SetInt64(1) } base.Mod(x.Abs(x), y.Abs(y)).Mul(base, n) U256(base) } self.Printf(" = %v", base) stack.push(base) case EXP: x, y := stack.pop(), stack.pop() self.Printf(" %v ** %v", x, y) base.Exp(x, y, Pow256) U256(base) self.Printf(" = %v", base) stack.push(base) case SIGNEXTEND: back := stack.pop() if back.Cmp(big.NewInt(31)) < 0 { bit := uint(back.Uint64()*8 + 7) num := stack.pop() mask := new(big.Int).Lsh(common.Big1, bit) mask.Sub(mask, common.Big1) if common.BitTest(num, int(bit)) { num.Or(num, mask.Not(mask)) } else { num.And(num, mask) } num = U256(num) self.Printf(" = %v", num) stack.push(num) } case NOT: stack.push(U256(new(big.Int).Not(stack.pop()))) //base.Sub(Pow256, stack.pop()).Sub(base, common.Big1) //base = U256(base) //stack.push(base) case LT: x, y := stack.pop(), stack.pop() self.Printf(" %v < %v", x, y) // x < y if x.Cmp(y) < 0 { stack.push(common.BigTrue) } else { stack.push(common.BigFalse) } case GT: x, y := stack.pop(), stack.pop() self.Printf(" %v > %v", x, y) // x > y if x.Cmp(y) > 0 { stack.push(common.BigTrue) } else { stack.push(common.BigFalse) } case SLT: x, y := S256(stack.pop()), S256(stack.pop()) self.Printf(" %v < %v", x, y) // x < y if x.Cmp(S256(y)) < 0 { stack.push(common.BigTrue) } else { stack.push(common.BigFalse) } case SGT: x, y := S256(stack.pop()), S256(stack.pop()) self.Printf(" %v > %v", x, y) // x > y if x.Cmp(y) > 0 { stack.push(common.BigTrue) } else { stack.push(common.BigFalse) } case EQ: x, y := stack.pop(), stack.pop() self.Printf(" %v == %v", y, x) // x == y if x.Cmp(y) == 0 { stack.push(common.BigTrue) } else { stack.push(common.BigFalse) } case ISZERO: x := stack.pop() if x.Cmp(common.BigFalse) > 0 { stack.push(common.BigFalse) } else { stack.push(common.BigTrue) } // 0x10 range case AND: x, y := stack.pop(), stack.pop() self.Printf(" %v & %v", y, x) stack.push(base.And(x, y)) case OR: x, y := stack.pop(), stack.pop() self.Printf(" %v | %v", x, y) stack.push(base.Or(x, y)) case XOR: x, y := stack.pop(), stack.pop() self.Printf(" %v ^ %v", x, y) stack.push(base.Xor(x, y)) case BYTE: th, val := stack.pop(), stack.pop() if th.Cmp(big.NewInt(32)) < 0 { byt := big.NewInt(int64(common.LeftPadBytes(val.Bytes(), 32)[th.Int64()])) base.Set(byt) } else { base.Set(common.BigFalse) } self.Printf(" => 0x%x", base.Bytes()) stack.push(base) case ADDMOD: x := stack.pop() y := stack.pop() z := stack.pop() if z.Cmp(Zero) > 0 { add := new(big.Int).Add(x, y) base.Mod(add, z) base = U256(base) } self.Printf(" %v + %v %% %v = %v", x, y, z, base) stack.push(base) case MULMOD: x := stack.pop() y := stack.pop() z := stack.pop() if z.Cmp(Zero) > 0 { mul := new(big.Int).Mul(x, y) base.Mod(mul, z) U256(base) } self.Printf(" %v + %v %% %v = %v", x, y, z, base) stack.push(base) // 0x20 range case SHA3: offset, size := stack.pop(), stack.pop() data := crypto.Sha3(mem.Get(offset.Int64(), size.Int64())) stack.push(common.BigD(data)) self.Printf(" => (%v) %x", size, data) // 0x30 range case ADDRESS: stack.push(common.Bytes2Big(context.Address().Bytes())) self.Printf(" => %x", context.Address()) case BALANCE: addr := common.BigToAddress(stack.pop()) balance := statedb.GetBalance(addr) stack.push(balance) self.Printf(" => %v (%x)", balance, addr) case ORIGIN: origin := self.env.Origin() stack.push(origin.Big()) self.Printf(" => %x", origin) case CALLER: caller := context.caller.Address() stack.push(common.Bytes2Big(caller.Bytes())) self.Printf(" => %x", caller) case CALLVALUE: stack.push(value) self.Printf(" => %v", value) case CALLDATALOAD: data := getData(callData, stack.pop(), common.Big32) self.Printf(" => 0x%x", data) stack.push(common.Bytes2Big(data)) case CALLDATASIZE: l := int64(len(callData)) stack.push(big.NewInt(l)) self.Printf(" => %d", l) case CALLDATACOPY: var ( mOff = stack.pop() cOff = stack.pop() l = stack.pop() ) data := getData(callData, cOff, l) mem.Set(mOff.Uint64(), l.Uint64(), data) self.Printf(" => [%v, %v, %v]", mOff, cOff, l) case CODESIZE, EXTCODESIZE: var code []byte if op == EXTCODESIZE { addr := common.BigToAddress(stack.pop()) code = statedb.GetCode(addr) } else { code = context.Code } l := big.NewInt(int64(len(code))) stack.push(l) self.Printf(" => %d", l) case CODECOPY, EXTCODECOPY: var code []byte if op == EXTCODECOPY { addr := common.BigToAddress(stack.pop()) code = statedb.GetCode(addr) } else { code = context.Code } var ( mOff = stack.pop() cOff = stack.pop() l = stack.pop() ) codeCopy := getData(code, cOff, l) mem.Set(mOff.Uint64(), l.Uint64(), codeCopy) self.Printf(" => [%v, %v, %v] %x", mOff, cOff, l, codeCopy) case GASPRICE: stack.push(context.Price) self.Printf(" => %x", context.Price) // 0x40 range case BLOCKHASH: num := stack.pop() n := new(big.Int).Sub(self.env.BlockNumber(), common.Big257) if num.Cmp(n) > 0 && num.Cmp(self.env.BlockNumber()) < 0 { stack.push(self.env.GetHash(num.Uint64()).Big()) } else { stack.push(common.Big0) } self.Printf(" => 0x%x", stack.peek().Bytes()) case COINBASE: coinbase := self.env.Coinbase() stack.push(coinbase.Big()) self.Printf(" => 0x%x", coinbase) case TIMESTAMP: time := self.env.Time() stack.push(big.NewInt(time)) self.Printf(" => 0x%x", time) case NUMBER: number := self.env.BlockNumber() stack.push(U256(number)) self.Printf(" => 0x%x", number.Bytes()) case DIFFICULTY: difficulty := self.env.Difficulty() stack.push(difficulty) self.Printf(" => 0x%x", difficulty.Bytes()) case GASLIMIT: self.Printf(" => %v", self.env.GasLimit()) stack.push(self.env.GasLimit()) // 0x50 range case PUSH1, PUSH2, PUSH3, PUSH4, PUSH5, PUSH6, PUSH7, PUSH8, PUSH9, PUSH10, PUSH11, PUSH12, PUSH13, PUSH14, PUSH15, PUSH16, PUSH17, PUSH18, PUSH19, PUSH20, PUSH21, PUSH22, PUSH23, PUSH24, PUSH25, PUSH26, PUSH27, PUSH28, PUSH29, PUSH30, PUSH31, PUSH32: a := big.NewInt(int64(op - PUSH1 + 1)) byts := getData(code, new(big.Int).Add(pc, big.NewInt(1)), a) // push value to stack stack.push(common.Bytes2Big(byts)) pc.Add(pc, a) self.Printf(" => 0x%x", byts) case POP: stack.pop() case DUP1, DUP2, DUP3, DUP4, DUP5, DUP6, DUP7, DUP8, DUP9, DUP10, DUP11, DUP12, DUP13, DUP14, DUP15, DUP16: n := int(op - DUP1 + 1) stack.dup(n) self.Printf(" => [%d] 0x%x", n, stack.peek().Bytes()) case SWAP1, SWAP2, SWAP3, SWAP4, SWAP5, SWAP6, SWAP7, SWAP8, SWAP9, SWAP10, SWAP11, SWAP12, SWAP13, SWAP14, SWAP15, SWAP16: n := int(op - SWAP1 + 2) stack.swap(n) self.Printf(" => [%d]", n) case LOG0, LOG1, LOG2, LOG3, LOG4: n := int(op - LOG0) topics := make([]common.Hash, n) mStart, mSize := stack.pop(), stack.pop() for i := 0; i < n; i++ { topics[i] = common.BigToHash(stack.pop()) //common.LeftPadBytes(stack.pop().Bytes(), 32) } data := mem.Get(mStart.Int64(), mSize.Int64()) log := &Log{context.Address(), topics, data, self.env.BlockNumber().Uint64()} self.env.AddLog(log) self.Printf(" => %v", log) case MLOAD: offset := stack.pop() val := common.BigD(mem.Get(offset.Int64(), 32)) stack.push(val) self.Printf(" => 0x%x", val.Bytes()) case MSTORE: // Store the value at stack top-1 in to memory at location stack top // pop value of the stack mStart, val := stack.pop(), stack.pop() mem.Set(mStart.Uint64(), 32, common.BigToBytes(val, 256)) self.Printf(" => 0x%x", val) case MSTORE8: off, val := stack.pop().Int64(), stack.pop().Int64() mem.store[off] = byte(val & 0xff) self.Printf(" => [%v] 0x%x", off, mem.store[off]) case SLOAD: loc := common.BigToHash(stack.pop()) val := common.Bytes2Big(statedb.GetState(context.Address(), loc)) stack.push(val) self.Printf(" {0x%x : 0x%x}", loc, val.Bytes()) case SSTORE: loc := common.BigToHash(stack.pop()) val := stack.pop() statedb.SetState(context.Address(), loc, val) self.Printf(" {0x%x : 0x%x}", loc, val.Bytes()) 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 } self.Printf(" ~> false") case JUMPDEST: case PC: //stack.push(big.NewInt(int64(pc))) stack.push(pc) case MSIZE: stack.push(big.NewInt(int64(mem.Len()))) case GAS: stack.push(context.Gas) self.Printf(" => %x", context.Gas) // 0x60 range case CREATE: var ( value = stack.pop() offset, size = stack.pop(), stack.pop() input = mem.Get(offset.Int64(), size.Int64()) gas = new(big.Int).Set(context.Gas) addr common.Address ) self.Endl() context.UseGas(context.Gas) ret, suberr, ref := self.env.Create(context, input, gas, price, value) if suberr != nil { stack.push(common.BigFalse) self.Printf(" (*) 0x0 %v", suberr) } else { // gas < len(ret) * CreateDataGas == NO_CODE dataGas := big.NewInt(int64(len(ret))) dataGas.Mul(dataGas, GasCreateByte) if context.UseGas(dataGas) { ref.SetCode(ret) } addr = ref.Address() stack.push(addr.Big()) } case CALL, CALLCODE: gas := stack.pop() // pop gas and value of the stack. addr, value := stack.pop(), stack.pop() value = U256(value) // pop input size and offset inOffset, inSize := stack.pop(), stack.pop() // pop return size and offset retOffset, retSize := stack.pop(), stack.pop() address := common.BigToAddress(addr) self.Printf(" => %x", address).Endl() // Get the arguments from the memory args := mem.Get(inOffset.Int64(), inSize.Int64()) if len(value.Bytes()) > 0 { gas.Add(gas, GasStipend) } var ( ret []byte err error ) if op == CALLCODE { ret, err = self.env.CallCode(context, address, args, gas, price, value) } else { ret, err = self.env.Call(context, address, args, gas, price, value) } if err != nil { stack.push(common.BigFalse) self.Printf("%v").Endl() } else { stack.push(common.BigTrue) mem.Set(retOffset.Uint64(), retSize.Uint64(), ret) } self.Printf("resume %x (%v)", context.Address(), context.Gas) case RETURN: offset, size := stack.pop(), stack.pop() ret := mem.Get(offset.Int64(), size.Int64()) self.Printf(" => [%v, %v] (%d) 0x%x", offset, size, len(ret), ret).Endl() return context.Return(ret), nil case SUICIDE: receiver := statedb.GetOrNewStateObject(common.BigToAddress(stack.pop())) balance := statedb.GetBalance(context.Address()) self.Printf(" => (%x) %v", receiver.Address().Bytes()[:4], balance) receiver.AddBalance(balance) statedb.Delete(context.Address()) fallthrough case STOP: // Stop the context self.Endl() return context.Return(nil), nil default: self.Printf("(pc) %-3v Invalid opcode %x\n", pc, op).Endl() return nil, fmt.Errorf("Invalid opcode %x", op) } pc.Add(pc, One) self.Endl() } } func (self *Vm) calculateGasAndSize(context *Context, caller ContextRef, op OpCode, statedb *state.StateDB, 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 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 } mSize, mStart := stack.data[stack.len()-2], stack.data[stack.len()-1] gas.Add(gas, GasLogBase) gas.Add(gas, new(big.Int).Mul(big.NewInt(int64(n)), GasLogTopic)) gas.Add(gas, new(big.Int).Mul(mSize, GasLogByte)) newMemSize = calcMemSize(mStart, mSize) case EXP: gas.Add(gas, new(big.Int).Mul(big.NewInt(int64(len(stack.data[stack.len()-2].Bytes()))), GasExpByte)) case SSTORE: err := stack.require(2) if err != nil { return nil, nil, err } var g *big.Int y, x := stack.data[stack.len()-2], stack.data[stack.len()-1] val := statedb.GetState(context.Address(), common.BigToHash(x)) if len(val) == 0 && len(y.Bytes()) > 0 { // 0 => non 0 g = GasStorageAdd } else if len(val) > 0 && len(y.Bytes()) == 0 { statedb.Refund(self.env.Origin(), RefundStorage) g = GasStorageMod } else { // non 0 => non 0 (or 0 => 0) g = GasStorageMod } gas.Set(g) case SUICIDE: if !statedb.IsDeleted(context.Address()) { statedb.Refund(self.env.Origin(), RefundSuicide) } case MLOAD: newMemSize = calcMemSize(stack.peek(), u256(32)) case MSTORE8: newMemSize = calcMemSize(stack.peek(), u256(1)) case MSTORE: newMemSize = calcMemSize(stack.peek(), u256(32)) case RETURN: newMemSize = calcMemSize(stack.peek(), stack.data[stack.len()-2]) case SHA3: newMemSize = calcMemSize(stack.peek(), stack.data[stack.len()-2]) words := toWordSize(stack.data[stack.len()-2]) gas.Add(gas, words.Mul(words, GasSha3Word)) case CALLDATACOPY: newMemSize = calcMemSize(stack.peek(), stack.data[stack.len()-3]) words := toWordSize(stack.data[stack.len()-3]) gas.Add(gas, words.Mul(words, GasCopyWord)) case CODECOPY: newMemSize = calcMemSize(stack.peek(), stack.data[stack.len()-3]) words := toWordSize(stack.data[stack.len()-3]) gas.Add(gas, words.Mul(words, GasCopyWord)) case 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, GasCopyWord)) case CREATE: newMemSize = calcMemSize(stack.data[stack.len()-2], stack.data[stack.len()-3]) case CALL, CALLCODE: gas.Add(gas, stack.data[stack.len()-1]) if op == CALL { if self.env.State().GetStateObject(common.BigToAddress(stack.data[stack.len()-2])) == nil { gas.Add(gas, GasCallNewAccount) } } if len(stack.data[stack.len()-3].Bytes()) > 0 { gas.Add(gas, GasCallValueTransfer) } 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) } if newMemSize.Cmp(common.Big0) > 0 { newMemSizeWords := toWordSize(newMemSize) newMemSize.Mul(newMemSizeWords, u256(32)) if newMemSize.Cmp(u256(int64(mem.Len()))) > 0 { oldSize := toWordSize(big.NewInt(int64(mem.Len()))) pow := new(big.Int).Exp(oldSize, common.Big2, Zero) linCoef := new(big.Int).Mul(oldSize, GasMemWord) quadCoef := new(big.Int).Div(pow, GasQuadCoeffDenom) oldTotalFee := new(big.Int).Add(linCoef, quadCoef) pow.Exp(newMemSizeWords, common.Big2, Zero) linCoef = new(big.Int).Mul(newMemSizeWords, GasMemWord) quadCoef = new(big.Int).Div(pow, GasQuadCoeffDenom) newTotalFee := new(big.Int).Add(linCoef, quadCoef) fee := new(big.Int).Sub(newTotalFee, oldTotalFee) gas.Add(gas, fee) } } return newMemSize, gas, nil } func (self *Vm) RunPrecompiled(p *PrecompiledAccount, callData []byte, context *Context) (ret []byte, err error) { gas := p.Gas(len(callData)) if context.UseGas(gas) { ret = p.Call(callData) self.Printf("NATIVE_FUNC => %x", ret) self.Endl() return context.Return(ret), nil } else { self.Printf("NATIVE_FUNC => failed").Endl() tmp := new(big.Int).Set(context.Gas) return nil, OOG(gas, tmp) } } func (self *Vm) Printf(format string, v ...interface{}) VirtualMachine { if self.debug { if self.logTy == LogTyPretty { self.logStr += fmt.Sprintf(format, v...) } } return self } func (self *Vm) Endl() VirtualMachine { if self.debug { if self.logTy == LogTyPretty { vmlogger.Infoln(self.logStr) self.logStr = "" } } return self } func (self *Vm) Env() Environment { return self.env }