diff options
Diffstat (limited to 'core/vm/gas_table.go')
-rw-r--r-- | core/vm/gas_table.go | 418 |
1 files changed, 294 insertions, 124 deletions
diff --git a/core/vm/gas_table.go b/core/vm/gas_table.go index 4d2c4e94a..fba1eb066 100644 --- a/core/vm/gas_table.go +++ b/core/vm/gas_table.go @@ -1,56 +1,80 @@ package vm import ( + gmath "math" "math/big" "github.com/ethereum/go-ethereum/common" + "github.com/ethereum/go-ethereum/common/math" "github.com/ethereum/go-ethereum/params" ) -func memoryGasCost(mem *Memory, newMemSize *big.Int) *big.Int { - gas := new(big.Int) - if newMemSize.Cmp(common.Big0) > 0 { - newMemSizeWords := toWordSize(newMemSize) - - if newMemSize.Cmp(u256(int64(mem.Len()))) > 0 { - // be careful reusing variables here when changing. - // The order has been optimised to reduce allocation - oldSize := toWordSize(big.NewInt(int64(mem.Len()))) - pow := new(big.Int).Exp(oldSize, common.Big2, Zero) - linCoef := oldSize.Mul(oldSize, params.MemoryGas) - quadCoef := new(big.Int).Div(pow, params.QuadCoeffDiv) - oldTotalFee := new(big.Int).Add(linCoef, quadCoef) - - pow.Exp(newMemSizeWords, common.Big2, Zero) - linCoef = linCoef.Mul(newMemSizeWords, params.MemoryGas) - quadCoef = quadCoef.Div(pow, params.QuadCoeffDiv) - newTotalFee := linCoef.Add(linCoef, quadCoef) - - fee := newTotalFee.Sub(newTotalFee, oldTotalFee) - gas.Add(gas, fee) - } +// memoryGasCosts calculates the quadratic gas for memory expansion. It does so +// only for the memory region that is expanded, not the total memory. +func memoryGasCost(mem *Memory, newMemSize uint64) (uint64, error) { + // The maximum that will fit in a uint64 is max_word_count - 1 + // anything above that will result in an overflow. + if newMemSize > gmath.MaxUint64-32 { + return 0, errGasUintOverflow + } + + if newMemSize == 0 { + return 0, nil } - return gas + + newMemSizeWords := toWordSize(newMemSize) + newMemSize = newMemSizeWords * 32 + + if newMemSize > uint64(mem.Len()) { + square := newMemSizeWords * newMemSizeWords + linCoef := newMemSizeWords * params.MemoryGas + quadCoef := square / params.QuadCoeffDiv + newTotalFee := linCoef + quadCoef + + fee := newTotalFee - mem.lastGasCost + mem.lastGasCost = newTotalFee + + return fee, nil + } + return 0, nil } -func constGasFunc(gas *big.Int) gasFunc { - return func(gt params.GasTable, env *EVM, contract *Contract, stack *Stack, mem *Memory, memorySize *big.Int) *big.Int { - return gas +func constGasFunc(gas uint64) gasFunc { + return func(gt params.GasTable, evm *EVM, contract *Contract, stack *Stack, mem *Memory, memorySize uint64) (uint64, error) { + return gas, nil } } -func gasCalldataCopy(gt params.GasTable, env *EVM, contract *Contract, stack *Stack, mem *Memory, memorySize *big.Int) *big.Int { - gas := memoryGasCost(mem, memorySize) - gas.Add(gas, GasFastestStep) - words := toWordSize(stack.Back(2)) +func gasCalldataCopy(gt params.GasTable, evm *EVM, contract *Contract, stack *Stack, mem *Memory, memorySize uint64) (uint64, error) { + gas, err := memoryGasCost(mem, memorySize) + if err != nil { + return 0, err + } + + var overflow bool + if gas, overflow = math.SafeAdd(gas, GasFastestStep); overflow { + return 0, errGasUintOverflow + } - return gas.Add(gas, words.Mul(words, params.CopyGas)) + words, overflow := bigUint64(stack.Back(2)) + if overflow { + return 0, errGasUintOverflow + } + + if words, overflow = math.SafeMul(toWordSize(words), params.CopyGas); overflow { + return 0, errGasUintOverflow + } + + if gas, overflow = math.SafeAdd(gas, words); overflow { + return 0, errGasUintOverflow + } + return gas, nil } -func gasSStore(gt params.GasTable, env *EVM, contract *Contract, stack *Stack, mem *Memory, memorySize *big.Int) *big.Int { +func gasSStore(gt params.GasTable, evm *EVM, contract *Contract, stack *Stack, mem *Memory, memorySize uint64) (uint64, error) { var ( y, x = stack.Back(1), stack.Back(0) - val = env.StateDB.GetState(contract.Address(), common.BigToHash(x)) + val = evm.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) @@ -58,189 +82,335 @@ func gasSStore(gt params.GasTable, env *EVM, contract *Contract, stack *Stack, m // 3. From a non-zero to a non-zero (CHANGE) if common.EmptyHash(val) && !common.EmptyHash(common.BigToHash(y)) { // 0 => non 0 - return new(big.Int).Set(params.SstoreSetGas) + return params.SstoreSetGas, nil } else if !common.EmptyHash(val) && common.EmptyHash(common.BigToHash(y)) { - env.StateDB.AddRefund(params.SstoreRefundGas) + evm.StateDB.AddRefund(new(big.Int).SetUint64(params.SstoreRefundGas)) - return new(big.Int).Set(params.SstoreClearGas) + return params.SstoreClearGas, nil } else { // non 0 => non 0 (or 0 => 0) - return new(big.Int).Set(params.SstoreResetGas) + return params.SstoreResetGas, nil } } -func makeGasLog(n uint) gasFunc { - return func(gt params.GasTable, env *EVM, contract *Contract, stack *Stack, mem *Memory, memorySize *big.Int) *big.Int { - mSize := stack.Back(1) +func makeGasLog(n uint64) gasFunc { + return func(gt params.GasTable, evm *EVM, contract *Contract, stack *Stack, mem *Memory, memorySize uint64) (uint64, error) { + requestedSize, overflow := bigUint64(stack.Back(1)) + if overflow { + return 0, errGasUintOverflow + } - gas := new(big.Int).Add(memoryGasCost(mem, memorySize), 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)) - return gas + gas, err := memoryGasCost(mem, memorySize) + if err != nil { + return 0, err + } + + if gas, overflow = math.SafeAdd(gas, params.LogGas); overflow { + return 0, errGasUintOverflow + } + if gas, overflow = math.SafeAdd(gas, n*params.LogTopicGas); overflow { + return 0, errGasUintOverflow + } + + var memorySizeGas uint64 + if memorySizeGas, overflow = math.SafeMul(requestedSize, params.LogDataGas); overflow { + return 0, errGasUintOverflow + } + if gas, overflow = math.SafeAdd(gas, memorySizeGas); overflow { + return 0, errGasUintOverflow + } + return gas, nil } } -func gasSha3(gt params.GasTable, env *EVM, contract *Contract, stack *Stack, mem *Memory, memorySize *big.Int) *big.Int { - gas := memoryGasCost(mem, memorySize) - gas.Add(gas, params.Sha3Gas) - words := toWordSize(stack.Back(1)) - return gas.Add(gas, words.Mul(words, params.Sha3WordGas)) -} +func gasSha3(gt params.GasTable, evm *EVM, contract *Contract, stack *Stack, mem *Memory, memorySize uint64) (uint64, error) { + var overflow bool + gas, err := memoryGasCost(mem, memorySize) + if err != nil { + return 0, err + } -func gasCodeCopy(gt params.GasTable, env *EVM, contract *Contract, stack *Stack, mem *Memory, memorySize *big.Int) *big.Int { - gas := memoryGasCost(mem, memorySize) - gas.Add(gas, GasFastestStep) - words := toWordSize(stack.Back(2)) + if gas, overflow = math.SafeAdd(gas, params.Sha3Gas); overflow { + return 0, errGasUintOverflow + } - return gas.Add(gas, words.Mul(words, params.CopyGas)) + wordGas, overflow := bigUint64(stack.Back(1)) + if overflow { + return 0, errGasUintOverflow + } + if wordGas, overflow = math.SafeMul(toWordSize(wordGas), params.Sha3WordGas); overflow { + return 0, errGasUintOverflow + } + if gas, overflow = math.SafeAdd(gas, wordGas); overflow { + return 0, errGasUintOverflow + } + return gas, nil } -func gasExtCodeCopy(gt params.GasTable, env *EVM, contract *Contract, stack *Stack, mem *Memory, memorySize *big.Int) *big.Int { - gas := memoryGasCost(mem, memorySize) - gas.Add(gas, gt.ExtcodeCopy) - words := toWordSize(stack.Back(3)) +func gasCodeCopy(gt params.GasTable, evm *EVM, contract *Contract, stack *Stack, mem *Memory, memorySize uint64) (uint64, error) { + gas, err := memoryGasCost(mem, memorySize) + if err != nil { + return 0, err + } + + var overflow bool + if gas, overflow = math.SafeAdd(gas, GasFastestStep); overflow { + return 0, errGasUintOverflow + } - return gas.Add(gas, words.Mul(words, params.CopyGas)) + wordGas, overflow := bigUint64(stack.Back(2)) + if overflow { + return 0, errGasUintOverflow + } + if wordGas, overflow = math.SafeMul(toWordSize(wordGas), params.CopyGas); overflow { + return 0, errGasUintOverflow + } + if gas, overflow = math.SafeAdd(gas, wordGas); overflow { + return 0, errGasUintOverflow + } + return gas, nil } -func gasMLoad(gt params.GasTable, env *EVM, contract *Contract, stack *Stack, mem *Memory, memorySize *big.Int) *big.Int { - return new(big.Int).Add(GasFastestStep, memoryGasCost(mem, memorySize)) +func gasExtCodeCopy(gt params.GasTable, evm *EVM, contract *Contract, stack *Stack, mem *Memory, memorySize uint64) (uint64, error) { + gas, err := memoryGasCost(mem, memorySize) + if err != nil { + return 0, err + } + + var overflow bool + if gas, overflow = math.SafeAdd(gas, gt.ExtcodeCopy); overflow { + return 0, errGasUintOverflow + } + + wordGas, overflow := bigUint64(stack.Back(3)) + if overflow { + return 0, errGasUintOverflow + } + + if wordGas, overflow = math.SafeMul(toWordSize(wordGas), params.CopyGas); overflow { + return 0, errGasUintOverflow + } + + if gas, overflow = math.SafeAdd(gas, wordGas); overflow { + return 0, errGasUintOverflow + } + return gas, nil } -func gasMStore8(gt params.GasTable, env *EVM, contract *Contract, stack *Stack, mem *Memory, memorySize *big.Int) *big.Int { - return new(big.Int).Add(GasFastestStep, memoryGasCost(mem, memorySize)) +func gasMLoad(gt params.GasTable, evm *EVM, contract *Contract, stack *Stack, mem *Memory, memorySize uint64) (uint64, error) { + var overflow bool + gas, err := memoryGasCost(mem, memorySize) + if err != nil { + return 0, errGasUintOverflow + } + if gas, overflow = math.SafeAdd(gas, GasFastestStep); overflow { + return 0, errGasUintOverflow + } + return gas, nil } -func gasMStore(gt params.GasTable, env *EVM, contract *Contract, stack *Stack, mem *Memory, memorySize *big.Int) *big.Int { - return new(big.Int).Add(GasFastestStep, memoryGasCost(mem, memorySize)) +func gasMStore8(gt params.GasTable, evm *EVM, contract *Contract, stack *Stack, mem *Memory, memorySize uint64) (uint64, error) { + var overflow bool + gas, err := memoryGasCost(mem, memorySize) + if err != nil { + return 0, errGasUintOverflow + } + if gas, overflow = math.SafeAdd(gas, GasFastestStep); overflow { + return 0, errGasUintOverflow + } + return gas, nil } -func gasCreate(gt params.GasTable, env *EVM, contract *Contract, stack *Stack, mem *Memory, memorySize *big.Int) *big.Int { - return new(big.Int).Add(params.CreateGas, memoryGasCost(mem, memorySize)) +func gasMStore(gt params.GasTable, evm *EVM, contract *Contract, stack *Stack, mem *Memory, memorySize uint64) (uint64, error) { + var overflow bool + gas, err := memoryGasCost(mem, memorySize) + if err != nil { + return 0, errGasUintOverflow + } + if gas, overflow = math.SafeAdd(gas, GasFastestStep); overflow { + return 0, errGasUintOverflow + } + return gas, nil } -func gasBalance(gt params.GasTable, env *EVM, contract *Contract, stack *Stack, mem *Memory, memorySize *big.Int) *big.Int { - return gt.Balance +func gasCreate(gt params.GasTable, evm *EVM, contract *Contract, stack *Stack, mem *Memory, memorySize uint64) (uint64, error) { + var overflow bool + gas, err := memoryGasCost(mem, memorySize) + if err != nil { + return 0, err + } + if gas, overflow = math.SafeAdd(gas, params.CreateGas); overflow { + return 0, errGasUintOverflow + } + return gas, nil } -func gasExtCodeSize(gt params.GasTable, env *EVM, contract *Contract, stack *Stack, mem *Memory, memorySize *big.Int) *big.Int { - return gt.ExtcodeSize +func gasBalance(gt params.GasTable, evm *EVM, contract *Contract, stack *Stack, mem *Memory, memorySize uint64) (uint64, error) { + return gt.Balance, nil } -func gasSLoad(gt params.GasTable, env *EVM, contract *Contract, stack *Stack, mem *Memory, memorySize *big.Int) *big.Int { - return gt.SLoad +func gasExtCodeSize(gt params.GasTable, evm *EVM, contract *Contract, stack *Stack, mem *Memory, memorySize uint64) (uint64, error) { + return gt.ExtcodeSize, nil } -func gasExp(gt params.GasTable, env *EVM, contract *Contract, stack *Stack, mem *Memory, memorySize *big.Int) *big.Int { - expByteLen := int64((stack.data[stack.len()-2].BitLen() + 7) / 8) - gas := big.NewInt(expByteLen) - gas.Mul(gas, gt.ExpByte) - return gas.Add(gas, GasSlowStep) +func gasSLoad(gt params.GasTable, evm *EVM, contract *Contract, stack *Stack, mem *Memory, memorySize uint64) (uint64, error) { + return gt.SLoad, nil } -func gasCall(gt params.GasTable, env *EVM, contract *Contract, stack *Stack, mem *Memory, memorySize *big.Int) *big.Int { - gas := new(big.Int).Set(gt.Calls) +func gasExp(gt params.GasTable, evm *EVM, contract *Contract, stack *Stack, mem *Memory, memorySize uint64) (uint64, error) { + expByteLen := uint64((stack.data[stack.len()-2].BitLen() + 7) / 8) - transfersValue := stack.Back(2).BitLen() > 0 var ( - address = common.BigToAddress(stack.Back(1)) - eip158 = env.ChainConfig().IsEIP158(env.BlockNumber) + gas = expByteLen * gt.ExpByte // no overflow check required. Max is 256 * ExpByte gas + overflow bool + ) + if gas, overflow = math.SafeAdd(gas, GasSlowStep); overflow { + return 0, errGasUintOverflow + } + return gas, nil +} + +func gasCall(gt params.GasTable, evm *EVM, contract *Contract, stack *Stack, mem *Memory, memorySize uint64) (uint64, error) { + var ( + gas = gt.Calls + transfersValue = stack.Back(2).BitLen() > 0 + address = common.BigToAddress(stack.Back(1)) + eip158 = evm.ChainConfig().IsEIP158(evm.BlockNumber) ) if eip158 { - if env.StateDB.Empty(address) && transfersValue { - gas.Add(gas, params.CallNewAccountGas) + if evm.StateDB.Empty(address) && transfersValue { + gas += params.CallNewAccountGas } - } else if !env.StateDB.Exist(address) { - gas.Add(gas, params.CallNewAccountGas) + } else if !evm.StateDB.Exist(address) { + gas += params.CallNewAccountGas } if transfersValue { - gas.Add(gas, params.CallValueTransferGas) + gas += params.CallValueTransferGas + } + memoryGas, err := memoryGasCost(mem, memorySize) + if err != nil { + return 0, err + } + var overflow bool + if gas, overflow = math.SafeAdd(gas, memoryGas); overflow { + return 0, errGasUintOverflow } - gas.Add(gas, memoryGasCost(mem, memorySize)) - cg := callGas(gt, contract.Gas, gas, stack.data[stack.len()-1]) + cg, err := callGas(gt, contract.Gas, gas, stack.Back(0)) + if err != nil { + return 0, err + } // 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 + stack.data[stack.len()-1] = new(big.Int).SetUint64(cg) - return gas.Add(gas, cg) + if gas, overflow = math.SafeAdd(gas, cg); overflow { + return 0, errGasUintOverflow + } + return gas, nil } -func gasCallCode(gt params.GasTable, env *EVM, contract *Contract, stack *Stack, mem *Memory, memorySize *big.Int) *big.Int { - gas := new(big.Int).Set(gt.Calls) +func gasCallCode(gt params.GasTable, evm *EVM, contract *Contract, stack *Stack, mem *Memory, memorySize uint64) (uint64, error) { + gas := gt.Calls if stack.Back(2).BitLen() > 0 { - gas.Add(gas, params.CallValueTransferGas) + gas += params.CallValueTransferGas + } + memoryGas, err := memoryGasCost(mem, memorySize) + if err != nil { + return 0, err + } + var overflow bool + if gas, overflow = math.SafeAdd(gas, memoryGas); overflow { + return 0, errGasUintOverflow } - gas.Add(gas, memoryGasCost(mem, memorySize)) - cg := callGas(gt, contract.Gas, gas, stack.data[stack.len()-1]) + cg, err := callGas(gt, contract.Gas, gas, stack.Back(0)) + if err != nil { + return 0, err + } // 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 + stack.data[stack.len()-1] = new(big.Int).SetUint64(cg) - return gas.Add(gas, cg) + if gas, overflow = math.SafeAdd(gas, cg); overflow { + return 0, errGasUintOverflow + } + return gas, nil } -func gasReturn(gt params.GasTable, env *EVM, contract *Contract, stack *Stack, mem *Memory, memorySize *big.Int) *big.Int { +func gasReturn(gt params.GasTable, evm *EVM, contract *Contract, stack *Stack, mem *Memory, memorySize uint64) (uint64, error) { return memoryGasCost(mem, memorySize) } -func gasSuicide(gt params.GasTable, env *EVM, contract *Contract, stack *Stack, mem *Memory, memorySize *big.Int) *big.Int { - gas := new(big.Int) +func gasSuicide(gt params.GasTable, evm *EVM, contract *Contract, stack *Stack, mem *Memory, memorySize uint64) (uint64, error) { + var gas uint64 // EIP150 homestead gas reprice fork: - if env.ChainConfig().IsEIP150(env.BlockNumber) { - gas.Set(gt.Suicide) + if evm.ChainConfig().IsEIP150(evm.BlockNumber) { + gas = gt.Suicide var ( address = common.BigToAddress(stack.Back(0)) - eip158 = env.ChainConfig().IsEIP158(env.BlockNumber) + eip158 = evm.ChainConfig().IsEIP158(evm.BlockNumber) ) if eip158 { // if empty and transfers value - if env.StateDB.Empty(address) && env.StateDB.GetBalance(contract.Address()).BitLen() > 0 { - gas.Add(gas, gt.CreateBySuicide) + if evm.StateDB.Empty(address) && evm.StateDB.GetBalance(contract.Address()).BitLen() > 0 { + gas += gt.CreateBySuicide } - } else if !env.StateDB.Exist(address) { - gas.Add(gas, gt.CreateBySuicide) + } else if !evm.StateDB.Exist(address) { + gas += gt.CreateBySuicide } } - if !env.StateDB.HasSuicided(contract.Address()) { - env.StateDB.AddRefund(params.SuicideRefundGas) + if !evm.StateDB.HasSuicided(contract.Address()) { + evm.StateDB.AddRefund(new(big.Int).SetUint64(params.SuicideRefundGas)) } - return gas + return gas, nil } -func gasDelegateCall(gt params.GasTable, env *EVM, contract *Contract, stack *Stack, mem *Memory, memorySize *big.Int) *big.Int { - gas := new(big.Int).Add(gt.Calls, memoryGasCost(mem, memorySize)) +func gasDelegateCall(gt params.GasTable, evm *EVM, contract *Contract, stack *Stack, mem *Memory, memorySize uint64) (uint64, error) { + gas, err := memoryGasCost(mem, memorySize) + if err != nil { + return 0, err + } + var overflow bool + if gas, overflow = math.SafeAdd(gas, gt.Calls); overflow { + return 0, errGasUintOverflow + } - cg := callGas(gt, contract.Gas, gas, stack.data[stack.len()-1]) + cg, err := callGas(gt, contract.Gas, gas, stack.Back(0)) + if err != nil { + return 0, err + } // 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 + stack.data[stack.len()-1] = new(big.Int).SetUint64(cg) - return gas.Add(gas, cg) + if gas, overflow = math.SafeAdd(gas, cg); overflow { + return 0, errGasUintOverflow + } + return gas, nil } -func gasPush(gt params.GasTable, env *EVM, contract *Contract, stack *Stack, mem *Memory, memorySize *big.Int) *big.Int { - return GasFastestStep +func gasPush(gt params.GasTable, evm *EVM, contract *Contract, stack *Stack, mem *Memory, memorySize uint64) (uint64, error) { + return GasFastestStep, nil } -func gasSwap(gt params.GasTable, env *EVM, contract *Contract, stack *Stack, mem *Memory, memorySize *big.Int) *big.Int { - return GasFastestStep +func gasSwap(gt params.GasTable, evm *EVM, contract *Contract, stack *Stack, mem *Memory, memorySize uint64) (uint64, error) { + return GasFastestStep, nil } -func gasDup(gt params.GasTable, env *EVM, contract *Contract, stack *Stack, mem *Memory, memorySize *big.Int) *big.Int { - return GasFastestStep +func gasDup(gt params.GasTable, evm *EVM, contract *Contract, stack *Stack, mem *Memory, memorySize uint64) (uint64, error) { + return GasFastestStep, nil } |