diff --git a/core/vm/eips.go b/core/vm/eips.go index 6e7259d405..075f5b7606 100644 --- a/core/vm/eips.go +++ b/core/vm/eips.go @@ -27,6 +27,8 @@ import ( // defined jump tables are not polluted. func EnableEIP(eipNum int, jt *JumpTable) error { switch eipNum { + case 2200: + enable2200(jt) case 1884: enable1884(jt) case 1344: @@ -83,3 +85,8 @@ func opChainID(pc *uint64, interpreter *EVMInterpreter, contract *Contract, memo stack.push(chainId) return nil, nil } + +// enable2200 applies EIP-2200 (Rebalance net-metered SSTORE) +func enable2200(jt *JumpTable) { + jt[SSTORE].dynamicGas = gasSStoreEIP2200 +} diff --git a/core/vm/gas_table.go b/core/vm/gas_table.go index b2999fdea7..1d3c4f1003 100644 --- a/core/vm/gas_table.go +++ b/core/vm/gas_table.go @@ -17,6 +17,8 @@ package vm import ( + "errors" + "github.com/ethereum/go-ethereum/common" "github.com/ethereum/go-ethereum/common/math" "github.com/ethereum/go-ethereum/params" @@ -160,6 +162,61 @@ func gasSStore(evm *EVM, contract *Contract, stack *Stack, mem *Memory, memorySi return params.NetSstoreDirtyGas, nil } +// 0. If *gasleft* is less than or equal to 2300, fail the current call. +// 1. If current value equals new value (this is a no-op), SSTORE_NOOP_GAS gas is deducted. +// 2. If current value does not equal new value: +// 2.1. If original value equals current value (this storage slot has not been changed by the current execution context): +// 2.1.1. If original value is 0, SSTORE_INIT_GAS gas is deducted. +// 2.1.2. Otherwise, SSTORE_CLEAN_GAS gas is deducted. If new value is 0, add SSTORE_CLEAR_REFUND to refund counter. +// 2.2. If original value does not equal current value (this storage slot is dirty), SSTORE_DIRTY_GAS gas is deducted. Apply both of the following clauses: +// 2.2.1. If original value is not 0: +// 2.2.1.1. If current value is 0 (also means that new value is not 0), subtract SSTORE_CLEAR_REFUND gas from refund counter. We can prove that refund counter will never go below 0. +// 2.2.1.2. If new value is 0 (also means that current value is not 0), add SSTORE_CLEAR_REFUND gas to refund counter. +// 2.2.2. If original value equals new value (this storage slot is reset): +// 2.2.2.1. If original value is 0, add SSTORE_INIT_REFUND to refund counter. +// 2.2.2.2. Otherwise, add SSTORE_CLEAN_REFUND gas to refund counter. +func gasSStoreEIP2200(evm *EVM, contract *Contract, stack *Stack, mem *Memory, memorySize uint64) (uint64, error) { + // If we fail the minimum gas availability invariant, fail (0) + if contract.Gas <= params.SstoreSentryGasEIP2200 { + return 0, errors.New("not enough gas for reentrancy sentry") + } + // Gas sentry honoured, do the actual gas calculation based on the stored value + var ( + y, x = stack.Back(1), stack.Back(0) + current = evm.StateDB.GetState(contract.Address(), common.BigToHash(x)) + ) + value := common.BigToHash(y) + + if current == value { // noop (1) + return params.SstoreNoopGasEIP2200, nil + } + original := evm.StateDB.GetCommittedState(contract.Address(), common.BigToHash(x)) + if original == current { + if original == (common.Hash{}) { // create slot (2.1.1) + return params.SstoreInitGasEIP2200, nil + } + if value == (common.Hash{}) { // delete slot (2.1.2b) + evm.StateDB.AddRefund(params.SstoreClearRefundEIP2200) + } + return params.SstoreCleanGasEIP2200, nil // write existing slot (2.1.2) + } + if original != (common.Hash{}) { + if current == (common.Hash{}) { // recreate slot (2.2.1.1) + evm.StateDB.SubRefund(params.SstoreClearRefundEIP2200) + } else if value == (common.Hash{}) { // delete slot (2.2.1.2) + evm.StateDB.AddRefund(params.SstoreClearRefundEIP2200) + } + } + if original == value { + if original == (common.Hash{}) { // reset to original inexistent slot (2.2.2.1) + evm.StateDB.AddRefund(params.SstoreInitRefundEIP2200) + } else { // reset to original existing slot (2.2.2.2) + evm.StateDB.AddRefund(params.SstoreCleanRefundEIP2200) + } + } + return params.SstoreDirtyGasEIP2200, nil // dirty update (2.2) +} + func makeGasLog(n uint64) gasFunc { return func(evm *EVM, contract *Contract, stack *Stack, mem *Memory, memorySize uint64) (uint64, error) { requestedSize, overflow := bigUint64(stack.Back(1)) diff --git a/core/vm/gas_table_test.go b/core/vm/gas_table_test.go index 2c1e11894f..5d443de0ea 100644 --- a/core/vm/gas_table_test.go +++ b/core/vm/gas_table_test.go @@ -16,7 +16,17 @@ package vm -import "testing" +import ( + "math" + "math/big" + "testing" + + "github.com/ethereum/go-ethereum/common" + "github.com/ethereum/go-ethereum/common/hexutil" + "github.com/ethereum/go-ethereum/core/rawdb" + "github.com/ethereum/go-ethereum/core/state" + "github.com/ethereum/go-ethereum/params" +) func TestMemoryGasCost(t *testing.T) { tests := []struct { @@ -37,3 +47,61 @@ func TestMemoryGasCost(t *testing.T) { } } } + +var eip2200Tests = []struct { + original byte + gaspool uint64 + input string + used uint64 + refund uint64 + failure error +}{ + {0, math.MaxUint64, "0x60006000556000600055", 1612, 0, nil}, // 0 -> 0 -> 0 + {0, math.MaxUint64, "0x60006000556001600055", 20812, 0, nil}, // 0 -> 0 -> 1 + {0, math.MaxUint64, "0x60016000556000600055", 20812, 19200, nil}, // 0 -> 1 -> 0 + {0, math.MaxUint64, "0x60016000556002600055", 20812, 0, nil}, // 0 -> 1 -> 2 + {0, math.MaxUint64, "0x60016000556001600055", 20812, 0, nil}, // 0 -> 1 -> 1 + {1, math.MaxUint64, "0x60006000556000600055", 5812, 15000, nil}, // 1 -> 0 -> 0 + {1, math.MaxUint64, "0x60006000556001600055", 5812, 4200, nil}, // 1 -> 0 -> 1 + {1, math.MaxUint64, "0x60006000556002600055", 5812, 0, nil}, // 1 -> 0 -> 2 + {1, math.MaxUint64, "0x60026000556000600055", 5812, 15000, nil}, // 1 -> 2 -> 0 + {1, math.MaxUint64, "0x60026000556003600055", 5812, 0, nil}, // 1 -> 2 -> 3 + {1, math.MaxUint64, "0x60026000556001600055", 5812, 4200, nil}, // 1 -> 2 -> 1 + {1, math.MaxUint64, "0x60026000556002600055", 5812, 0, nil}, // 1 -> 2 -> 2 + {1, math.MaxUint64, "0x60016000556000600055", 5812, 15000, nil}, // 1 -> 1 -> 0 + {1, math.MaxUint64, "0x60016000556002600055", 5812, 0, nil}, // 1 -> 1 -> 2 + {1, math.MaxUint64, "0x60016000556001600055", 1612, 0, nil}, // 1 -> 1 -> 1 + {0, math.MaxUint64, "0x600160005560006000556001600055", 40818, 19200, nil}, // 0 -> 1 -> 0 -> 1 + {1, math.MaxUint64, "0x600060005560016000556000600055", 10818, 19200, nil}, // 1 -> 0 -> 1 -> 0 + {1, 2306, "0x6001600055", 2306, 0, ErrOutOfGas}, // 1 -> 1 (2300 sentry + 2xPUSH) + {1, 2307, "0x6001600055", 806, 0, nil}, // 1 -> 1 (2301 sentry + 2xPUSH) +} + +func TestEIP2200(t *testing.T) { + for i, tt := range eip2200Tests { + address := common.BytesToAddress([]byte("contract")) + + statedb, _ := state.New(common.Hash{}, state.NewDatabase(rawdb.NewMemoryDatabase())) + statedb.CreateAccount(address) + statedb.SetCode(address, hexutil.MustDecode(tt.input)) + statedb.SetState(address, common.Hash{}, common.BytesToHash([]byte{tt.original})) + statedb.Finalise(true) // Push the state into the "original" slot + + vmctx := Context{ + CanTransfer: func(StateDB, common.Address, *big.Int) bool { return true }, + Transfer: func(StateDB, common.Address, common.Address, *big.Int) {}, + } + vmenv := NewEVM(vmctx, statedb, params.AllEthashProtocolChanges, Config{ExtraEips: []int{2200}}) + + _, gas, err := vmenv.Call(AccountRef(common.Address{}), address, nil, tt.gaspool, new(big.Int)) + if err != tt.failure { + t.Errorf("test %d: failure mismatch: have %v, want %v", i, err, tt.failure) + } + if used := tt.gaspool - gas; used != tt.used { + t.Errorf("test %d: gas used mismatch: have %v, want %v", i, used, tt.used) + } + if refund := vmenv.StateDB.GetRefund(); refund != tt.refund { + t.Errorf("test %d: gas refund mismatch: have %v, want %v", i, refund, tt.refund) + } + } +} diff --git a/params/protocol_params.go b/params/protocol_params.go index 3022b700df..11b858a61c 100644 --- a/params/protocol_params.go +++ b/params/protocol_params.go @@ -52,6 +52,15 @@ const ( NetSstoreResetRefund uint64 = 4800 // Once per SSTORE operation for resetting to the original non-zero value NetSstoreResetClearRefund uint64 = 19800 // Once per SSTORE operation for resetting to the original zero value + SstoreSentryGasEIP2200 uint64 = 2300 // Minimum gas required to be present for an SSTORE call, not consumed + SstoreNoopGasEIP2200 uint64 = 800 // Once per SSTORE operation if the value doesn't change. + SstoreDirtyGasEIP2200 uint64 = 800 // Once per SSTORE operation if a dirty value is changed. + SstoreInitGasEIP2200 uint64 = 20000 // Once per SSTORE operation from clean zero to non-zero + SstoreInitRefundEIP2200 uint64 = 19200 // Once per SSTORE operation for resetting to the original zero value + SstoreCleanGasEIP2200 uint64 = 5000 // Once per SSTORE operation from clean non-zero to something else + SstoreCleanRefundEIP2200 uint64 = 4200 // Once per SSTORE operation for resetting to the original non-zero value + SstoreClearRefundEIP2200 uint64 = 15000 // Once per SSTORE operation for clearing an originally existing storage slot + JumpdestGas uint64 = 1 // Once per JUMPDEST operation. EpochDuration uint64 = 30000 // Duration between proof-of-work epochs.