bsc/vm/vm.go
2014-10-31 12:37:43 +01:00

721 lines
14 KiB
Go

package vm
import (
"fmt"
"math/big"
"github.com/ethereum/go-ethereum/crypto"
"github.com/ethereum/go-ethereum/ethutil"
)
// BIG FAT WARNING. THIS VM IS NOT YET IS USE!
// I want to get all VM tests pass first before updating this VM
type Vm struct {
env Environment
err error
depth int
}
func New(env Environment, typ Type) VirtualMachine {
switch typ {
case DebugVmTy:
return NewDebugVm(env)
default:
return &Vm{env: env}
}
}
func (self *Vm) RunClosure(closure *Closure) (ret []byte, err error) {
self.depth++
// Recover from any require exception
defer func() {
if r := recover(); r != nil {
ret = closure.Return(nil)
err = fmt.Errorf("%v", r)
}
}()
// Don't bother with the execution if there's no code.
if len(closure.Code) == 0 {
return closure.Return(nil), nil
}
var (
op OpCode
mem = &Memory{}
stack = NewStack()
pc = 0
step = 0
require = func(m int) {
if stack.Len() < m {
panic(fmt.Sprintf("%04v (%v) stack err size = %d, required = %d", pc, op, stack.Len(), m))
}
}
)
for {
// The base for all big integer arithmetic
base := new(big.Int)
step++
// Get the memory location of pc
op := closure.GetOp(pc)
gas := new(big.Int)
addStepGasUsage := func(amount *big.Int) {
gas.Add(gas, amount)
}
addStepGasUsage(GasStep)
var newMemSize *big.Int = ethutil.Big0
switch op {
case STOP:
gas.Set(ethutil.Big0)
case SUICIDE:
gas.Set(ethutil.Big0)
case SLOAD:
gas.Set(GasSLoad)
case SSTORE:
var mult *big.Int
y, x := stack.Peekn()
val := closure.GetStorage(x)
if val.BigInt().Cmp(ethutil.Big0) == 0 && len(y.Bytes()) > 0 {
mult = ethutil.Big2
} else if val.BigInt().Cmp(ethutil.Big0) != 0 && len(y.Bytes()) == 0 {
mult = ethutil.Big0
} else {
mult = ethutil.Big1
}
gas = new(big.Int).Mul(mult, GasSStore)
case BALANCE:
gas.Set(GasBalance)
case MSTORE:
require(2)
newMemSize = calcMemSize(stack.Peek(), u256(32))
case MLOAD:
require(1)
newMemSize = calcMemSize(stack.Peek(), u256(32))
case MSTORE8:
require(2)
newMemSize = calcMemSize(stack.Peek(), u256(1))
case RETURN:
require(2)
newMemSize = calcMemSize(stack.Peek(), stack.data[stack.Len()-2])
case SHA3:
require(2)
gas.Set(GasSha)
newMemSize = calcMemSize(stack.Peek(), stack.data[stack.Len()-2])
case CALLDATACOPY:
require(2)
newMemSize = calcMemSize(stack.Peek(), stack.data[stack.Len()-3])
case CODECOPY:
require(3)
newMemSize = calcMemSize(stack.Peek(), stack.data[stack.Len()-3])
case EXTCODECOPY:
require(4)
newMemSize = calcMemSize(stack.data[stack.Len()-2], stack.data[stack.Len()-4])
case CALL, CALLCODE:
require(7)
gas.Set(GasCall)
addStepGasUsage(stack.data[stack.Len()-1])
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 = ethutil.BigMax(x, y)
case CREATE:
require(3)
gas.Set(GasCreate)
newMemSize = calcMemSize(stack.data[stack.Len()-2], stack.data[stack.Len()-3])
}
if newMemSize.Cmp(ethutil.Big0) > 0 {
newMemSize.Add(newMemSize, u256(31))
newMemSize.Div(newMemSize, u256(32))
newMemSize.Mul(newMemSize, u256(32))
if newMemSize.Cmp(u256(int64(mem.Len()))) > 0 {
memGasUsage := new(big.Int).Sub(newMemSize, u256(int64(mem.Len())))
memGasUsage.Mul(GasMemory, memGasUsage)
memGasUsage.Div(memGasUsage, u256(32))
addStepGasUsage(memGasUsage)
}
}
if !closure.UseGas(gas) {
err := fmt.Errorf("Insufficient gas for %v. req %v has %v", op, gas, closure.Gas)
closure.UseGas(closure.Gas)
return closure.Return(nil), err
}
mem.Resize(newMemSize.Uint64())
switch op {
// 0x20 range
case ADD:
require(2)
x, y := stack.Popn()
base.Add(y, x)
U256(base)
// Pop result back on the stack
stack.Push(base)
case SUB:
require(2)
x, y := stack.Popn()
base.Sub(y, x)
U256(base)
// Pop result back on the stack
stack.Push(base)
case MUL:
require(2)
x, y := stack.Popn()
base.Mul(y, x)
U256(base)
// Pop result back on the stack
stack.Push(base)
case DIV:
require(2)
x, y := stack.Popn()
if x.Cmp(ethutil.Big0) != 0 {
base.Div(y, x)
}
U256(base)
// Pop result back on the stack
stack.Push(base)
case SDIV:
require(2)
y, x := S256(stack.Pop()), S256(stack.Pop())
if x.Cmp(ethutil.Big0) == 0 {
base.Set(ethutil.Big0)
} else {
n := new(big.Int)
if new(big.Int).Mul(y, x).Cmp(ethutil.Big0) < 0 {
n.SetInt64(-1)
} else {
n.SetInt64(1)
}
base.Div(y.Abs(y), x.Mul(x.Abs(x), n))
U256(base)
}
stack.Push(base)
case MOD:
require(2)
x, y := stack.Popn()
base.Mod(y, x)
U256(base)
stack.Push(base)
case SMOD:
require(2)
y, x := S256(stack.Pop()), S256(stack.Pop())
if x.Cmp(ethutil.Big0) == 0 {
base.Set(ethutil.Big0)
} else {
n := new(big.Int)
if y.Cmp(ethutil.Big0) < 0 {
n.SetInt64(-1)
} else {
n.SetInt64(1)
}
base.Mod(y.Abs(y), x.Mul(x.Abs(x), n))
U256(base)
}
stack.Push(base)
case EXP:
require(2)
x, y := stack.Popn()
base.Exp(y, x, Pow256)
U256(base)
stack.Push(base)
case BNOT:
require(1)
base.Sub(Pow256, stack.Pop())
base = U256(base)
stack.Push(base)
case LT:
require(2)
x, y := stack.Popn()
// x < y
if y.Cmp(x) < 0 {
stack.Push(ethutil.BigTrue)
} else {
stack.Push(ethutil.BigFalse)
}
case GT:
require(2)
x, y := stack.Popn()
// x > y
if y.Cmp(x) > 0 {
stack.Push(ethutil.BigTrue)
} else {
stack.Push(ethutil.BigFalse)
}
case SLT:
require(2)
y, x := S256(stack.Pop()), S256(stack.Pop())
// x < y
if y.Cmp(S256(x)) < 0 {
stack.Push(ethutil.BigTrue)
} else {
stack.Push(ethutil.BigFalse)
}
case SGT:
require(2)
y, x := S256(stack.Pop()), S256(stack.Pop())
// x > y
if y.Cmp(x) > 0 {
stack.Push(ethutil.BigTrue)
} else {
stack.Push(ethutil.BigFalse)
}
case EQ:
require(2)
x, y := stack.Popn()
// x == y
if x.Cmp(y) == 0 {
stack.Push(ethutil.BigTrue)
} else {
stack.Push(ethutil.BigFalse)
}
case NOT:
require(1)
x := stack.Pop()
if x.Cmp(ethutil.BigFalse) > 0 {
stack.Push(ethutil.BigFalse)
} else {
stack.Push(ethutil.BigTrue)
}
// 0x10 range
case AND:
require(2)
x, y := stack.Popn()
stack.Push(base.And(y, x))
case OR:
require(2)
x, y := stack.Popn()
stack.Push(base.Or(y, x))
case XOR:
require(2)
x, y := stack.Popn()
stack.Push(base.Xor(y, x))
case BYTE:
require(2)
val, th := stack.Popn()
if th.Cmp(big.NewInt(32)) < 0 && th.Cmp(big.NewInt(int64(len(val.Bytes())))) < 0 {
byt := big.NewInt(int64(ethutil.LeftPadBytes(val.Bytes(), 32)[th.Int64()]))
stack.Push(byt)
} else {
stack.Push(ethutil.BigFalse)
}
case ADDMOD:
require(3)
x := stack.Pop()
y := stack.Pop()
z := stack.Pop()
base.Add(x, y)
base.Mod(base, z)
U256(base)
stack.Push(base)
case MULMOD:
require(3)
x := stack.Pop()
y := stack.Pop()
z := stack.Pop()
base.Mul(x, y)
base.Mod(base, z)
U256(base)
stack.Push(base)
// 0x20 range
case SHA3:
require(2)
size, offset := stack.Popn()
data := crypto.Sha3(mem.Get(offset.Int64(), size.Int64()))
stack.Push(ethutil.BigD(data))
// 0x30 range
case ADDRESS:
stack.Push(ethutil.BigD(closure.Address()))
case BALANCE:
require(1)
addr := stack.Pop().Bytes()
balance := self.env.State().GetBalance(addr)
stack.Push(balance)
case ORIGIN:
origin := self.env.Origin()
stack.Push(ethutil.BigD(origin))
case CALLER:
caller := closure.caller.Address()
stack.Push(ethutil.BigD(caller))
case CALLVALUE:
value := closure.exe.value
stack.Push(value)
case CALLDATALOAD:
require(1)
var (
offset = stack.Pop()
data = make([]byte, 32)
lenData = big.NewInt(int64(len(closure.Args)))
)
if lenData.Cmp(offset) >= 0 {
length := new(big.Int).Add(offset, ethutil.Big32)
length = ethutil.BigMin(length, lenData)
copy(data, closure.Args[offset.Int64():length.Int64()])
}
stack.Push(ethutil.BigD(data))
case CALLDATASIZE:
l := int64(len(closure.Args))
stack.Push(big.NewInt(l))
case CALLDATACOPY:
var (
size = int64(len(closure.Args))
mOff = stack.Pop().Int64()
cOff = stack.Pop().Int64()
l = stack.Pop().Int64()
)
if cOff > size {
cOff = 0
l = 0
} else if cOff+l > size {
l = 0
}
code := closure.Args[cOff : cOff+l]
mem.Set(mOff, l, code)
case CODESIZE, EXTCODESIZE:
var code []byte
if op == EXTCODECOPY {
addr := stack.Pop().Bytes()
code = self.env.State().GetCode(addr)
} else {
code = closure.Code
}
l := big.NewInt(int64(len(code)))
stack.Push(l)
case CODECOPY, EXTCODECOPY:
var code []byte
if op == EXTCODECOPY {
addr := stack.Pop().Bytes()
code = self.env.State().GetCode(addr)
} else {
code = closure.Code
}
var (
size = int64(len(code))
mOff = stack.Pop().Int64()
cOff = stack.Pop().Int64()
l = stack.Pop().Int64()
)
if cOff > size {
cOff = 0
l = 0
} else if cOff+l > size {
l = 0
}
codeCopy := code[cOff : cOff+l]
mem.Set(mOff, l, codeCopy)
case GASPRICE:
stack.Push(closure.Price)
// 0x40 range
case PREVHASH:
prevHash := self.env.PrevHash()
stack.Push(ethutil.BigD(prevHash))
case COINBASE:
coinbase := self.env.Coinbase()
stack.Push(ethutil.BigD(coinbase))
case TIMESTAMP:
time := self.env.Time()
stack.Push(big.NewInt(time))
case NUMBER:
number := self.env.BlockNumber()
stack.Push(number)
case DIFFICULTY:
difficulty := self.env.Difficulty()
stack.Push(difficulty)
case GASLIMIT:
// TODO
stack.Push(big.NewInt(0))
// 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 := int(op - PUSH1 + 1)
val := ethutil.BigD(closure.GetBytes(int(pc+1), a))
// Push value to stack
stack.Push(val)
pc += a
step += int(op) - int(PUSH1) + 1
case POP:
require(1)
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.Dupn(n)
case SWAP1, SWAP2, SWAP3, SWAP4, SWAP5, SWAP6, SWAP7, SWAP8, SWAP9, SWAP10, SWAP11, SWAP12, SWAP13, SWAP14, SWAP15, SWAP16:
n := int(op - SWAP1 + 2)
stack.Swapn(n)
case MLOAD:
require(1)
offset := stack.Pop()
val := ethutil.BigD(mem.Get(offset.Int64(), 32))
stack.Push(val)
case MSTORE: // Store the value at stack top-1 in to memory at location stack top
require(2)
// Pop value of the stack
val, mStart := stack.Popn()
mem.Set(mStart.Int64(), 32, ethutil.BigToBytes(val, 256))
case MSTORE8:
require(2)
off := stack.Pop()
val := stack.Pop()
mem.store[off.Int64()] = byte(val.Int64() & 0xff)
case SLOAD:
require(1)
loc := stack.Pop()
val := closure.GetStorage(loc)
stack.Push(val.BigInt())
case SSTORE:
require(2)
val, loc := stack.Popn()
closure.SetStorage(loc, ethutil.NewValue(val))
closure.message.AddStorageChange(loc.Bytes())
case JUMP:
require(1)
pc = int(stack.Pop().Int64())
// Reduce pc by one because of the increment that's at the end of this for loop
continue
case JUMPI:
require(2)
cond, pos := stack.Popn()
if cond.Cmp(ethutil.BigTrue) >= 0 {
pc = int(pos.Int64())
if closure.GetOp(int(pc)) != JUMPDEST {
return closure.Return(nil), fmt.Errorf("JUMP missed JUMPDEST %v", pc)
}
continue
}
case JUMPDEST:
case PC:
stack.Push(u256(int64(pc)))
case MSIZE:
stack.Push(big.NewInt(int64(mem.Len())))
case GAS:
stack.Push(closure.Gas)
// 0x60 range
case CREATE:
require(3)
var (
err error
value = stack.Pop()
size, offset = stack.Popn()
input = mem.Get(offset.Int64(), size.Int64())
gas = new(big.Int).Set(closure.Gas)
// Snapshot the current stack so we are able to
// revert back to it later.
//snapshot = self.env.State().Copy()
)
// Generate a new address
addr := crypto.CreateAddress(closure.Address(), closure.object.Nonce)
closure.object.Nonce++
closure.UseGas(closure.Gas)
msg := NewExecution(self, addr, input, gas, closure.Price, value)
ret, err := msg.Exec(addr, closure)
if err != nil {
stack.Push(ethutil.BigFalse)
// Revert the state as it was before.
//self.env.State().Set(snapshot)
} else {
msg.object.Code = ret
stack.Push(ethutil.BigD(addr))
}
case CALL, CALLCODE:
require(7)
gas := stack.Pop()
// Pop gas and value of the stack.
value, addr := stack.Popn()
// Pop input size and offset
inSize, inOffset := stack.Popn()
// Pop return size and offset
retSize, retOffset := stack.Popn()
// Get the arguments from the memory
args := mem.Get(inOffset.Int64(), inSize.Int64())
var executeAddr []byte
if op == CALLCODE {
executeAddr = closure.Address()
} else {
executeAddr = addr.Bytes()
}
msg := NewExecution(self, executeAddr, args, gas, closure.Price, value)
ret, err := msg.Exec(addr.Bytes(), closure)
if err != nil {
stack.Push(ethutil.BigFalse)
} else {
stack.Push(ethutil.BigTrue)
mem.Set(retOffset.Int64(), retSize.Int64(), ret)
}
case RETURN:
require(2)
size, offset := stack.Popn()
ret := mem.Get(offset.Int64(), size.Int64())
return closure.Return(ret), nil
case SUICIDE:
require(1)
receiver := self.env.State().GetOrNewStateObject(stack.Pop().Bytes())
receiver.AddAmount(closure.object.Balance())
closure.object.MarkForDeletion()
fallthrough
case STOP: // Stop the closure
return closure.Return(nil), nil
default:
vmlogger.Debugf("(pc) %-3v Invalid opcode %x\n", pc, op)
//panic(fmt.Sprintf("Invalid opcode %x", op))
return closure.Return(nil), fmt.Errorf("Invalid opcode %x", op)
}
pc++
}
}
func (self *Vm) Env() Environment {
return self.env
}
func (self *Vm) Depth() int {
return self.depth
}
func (self *Vm) Printf(format string, v ...interface{}) VirtualMachine { return self }
func (self *Vm) Endl() VirtualMachine { return self }