nimbus-eth1/nimbus/transaction/call_evm.nim

300 lines
11 KiB
Nim

# Nimbus - Various ways of calling the EVM
#
# Copyright (c) 2018-2021 Status Research & Development GmbH
# Licensed under either of
# * Apache License, version 2.0, ([LICENSE-APACHE](LICENSE-APACHE) or http://www.apache.org/licenses/LICENSE-2.0)
# * MIT license ([LICENSE-MIT](LICENSE-MIT) or http://opensource.org/licenses/MIT)
# at your option. This file may not be copied, modified, or distributed except according to those terms.
import
eth/common/eth_types, stint, options, stew/byteutils,
".."/[vm_types, vm_types2, vm_state, vm_computation, utils],
".."/[db/db_chain, config, vm_state_transactions, rpc/hexstrings],
".."/[db/accounts_cache, transaction, vm_precompiles, vm_gas_costs], eth/trie/db,
".."/vm_internals,
./call_common
type
RpcCallData* = object
source*: EthAddress
to*: EthAddress
gas*: GasInt
gasPrice*: GasInt
value*: UInt256
data*: seq[byte]
contractCreation*: bool
proc rpcSetupComputation(vmState: BaseVMState, rpc: RpcCallData,
gasLimit: GasInt, forkOverride = none(Fork)): Computation =
return setupComputation(CallParams(
vmState: vmState,
forkOverride: forkOverride,
gasPrice: rpc.gasPrice,
gasLimit: gasLimit,
sender: rpc.source,
to: rpc.to,
isCreate: rpc.contractCreation,
value: rpc.value,
input: rpc.data
))
proc rpcDoCall*(call: RpcCallData, header: BlockHeader, chain: BaseChainDB): HexDataStr =
# TODO: handle revert and error
# TODO: handle contract ABI
var
# we use current header stateRoot, unlike block validation
# which use previous block stateRoot
vmState = newBaseVMState(header.stateRoot, header, chain)
comp = rpcSetupComputation(vmState, call, call.gas)
comp.execComputation()
result = hexDataStr(comp.output)
proc rpcMakeCall*(call: RpcCallData, header: BlockHeader, chain: BaseChainDB): (string, GasInt, bool) =
# TODO: handle revert
var
parent = chain.getBlockHeader(header.parentHash)
vmState = newBaseVMState(parent.stateRoot, header, chain)
fork = toFork(chain.config, header.blockNumber)
comp = rpcSetupComputation(vmState, call, call.gas, some(fork))
let gas = comp.gasMeter.gasRemaining
comp.execComputation()
return (comp.output.toHex, gas - comp.gasMeter.gasRemaining, comp.isError)
func rpcIntrinsicGas(call: RpcCallData, fork: Fork): GasInt =
var intrinsicGas = call.data.intrinsicGas(fork)
if call.contractCreation:
intrinsicGas = intrinsicGas + gasFees[fork][GasTXCreate]
return intrinsicGas
func rpcValidateCall(call: RpcCallData, vmState: BaseVMState, gasLimit: GasInt,
fork: Fork, intrinsicGas: var GasInt, gasCost: var UInt256): bool =
# This behaviour matches `validateTransaction`, used by `processTransaction`.
if vmState.cumulativeGasUsed + gasLimit > vmState.blockHeader.gasLimit:
return false
let balance = vmState.readOnlyStateDB.getBalance(call.source)
gasCost = gasLimit.u256 * call.gasPrice.u256
if gasCost > balance or call.value > balance - gasCost:
return false
intrinsicGas = rpcIntrinsicGas(call, fork)
if intrinsicGas > gasLimit:
return false
return true
proc rpcInitialAccessListEIP2929(call: RpcCallData, vmState: BaseVMState, fork: Fork) =
# EIP2929 initial access list.
if fork >= FkBerlin:
vmState.mutateStateDB:
db.accessList(call.source)
# For contract creations the EVM will add the contract address to the
# access list itself, after calculating the new contract address.
if not call.contractCreation:
db.accessList(call.to)
for c in activePrecompiles():
db.accessList(c)
proc rpcEstimateGas*(call: RpcCallData, header: BlockHeader, chain: BaseChainDB, haveGasLimit: bool): GasInt =
# TODO: handle revert and error
var
# we use current header stateRoot, unlike block validation
# which use previous block stateRoot
vmState = newBaseVMState(header.stateRoot, header, chain)
fork = toFork(chain.config, header.blockNumber)
gasLimit = if haveGasLimit: call.gas else: header.gasLimit - vmState.cumulativeGasUsed
intrinsicGas: GasInt
gasCost: UInt256
# Nimbus `estimateGas` has historically checked against remaining gas in the
# current block, balance in the sender account (even if the sender is default
# account 0x00), and other limits, and returned 0 as the gas estimate if any
# checks failed. This behaviour came from how it used `processTransaction`
# which calls `validateTransaction`. For now, keep this behaviour the same.
# Compare this code with `validateTransaction`.
#
# TODO: This historically differs from `rpcDoCall` and `rpcMakeCall`. There
# are other differences in rpc_utils.nim `callData` too. Are the different
# behaviours intended, and is 0 the correct return value to mean "not enough
# gas to start"? Probably not.
if not rpcValidateCall(call, vmState, gasLimit, fork, intrinsicGas, gasCost):
return 0
var dbTx = chain.db.beginTransaction()
defer: dbTx.dispose()
# TODO: EIP2929 setup also historically differs from `rpcDoCall` and `rpcMakeCall`.
rpcInitialAccessListEIP2929(call, vmState, fork)
# TODO: Deduction of `intrinsicGas` also differs from `rpcDoCall` and `rpcMakeCall`.
var c = rpcSetupComputation(vmState, call, gasLimit - intrinsicGas, some(fork))
vmState.mutateStateDB:
db.subBalance(call.source, gasCost)
execComputation(c)
if c.shouldBurnGas:
return gasLimit
let maxRefund = (gasLimit - c.gasMeter.gasRemaining) div 2
let refund = min(c.getGasRefund(), maxRefund)
return gasLimit - c.gasMeter.gasRemaining - refund
proc txSetupComputation(tx: Transaction, sender: EthAddress, vmState: BaseVMState, fork: Fork): Computation =
var gas = tx.gasLimit - tx.intrinsicGas(fork)
assert gas >= 0
return setupComputation(CallParams(
vmState: vmState,
forkOverride: some(fork),
gasPrice: tx.gasPrice,
gasLimit: gas,
sender: sender,
to: tx.to,
isCreate: tx.isContractCreation,
value: tx.value,
input: tx.payload
))
proc txRefundgas(tx: Transaction, sender: EthAddress, c: Computation) =
let maxRefund = (tx.gasLimit - c.gasMeter.gasRemaining) div 2
let refund = min(c.getGasRefund(), maxRefund)
c.gasMeter.returnGas(refund)
c.vmState.mutateStateDB:
db.addBalance(sender, c.gasMeter.gasRemaining.u256 * tx.gasPrice.u256)
proc txInitialAccessListEIP2929(tx: Transaction, sender: EthAddress, vmState: BaseVMState, fork: Fork) =
# EIP2929 initial access list.
if fork >= FkBerlin:
vmState.mutateStateDB:
db.accessList(sender)
# For contract creations the EVM will add the contract address to the
# access list itself, after calculating the new contract address.
if not tx.isContractCreation:
db.accessList(tx.getRecipient(sender))
for c in activePrecompiles():
db.accessList(c)
# EIP2930 optional access list
if tx.txType == AccessListTxType:
for n in tx.accessListTx.accessList:
db.accessList(n.address)
for x in n.storageKeys:
db.accessList(n.address, UInt256.fromBytesBE(x))
proc txCallEvm*(tx: Transaction, sender: EthAddress, vmState: BaseVMState, fork: Fork): GasInt =
txInitialAccessListEIP2929(tx, sender, vmState, fork)
var c = txSetupComputation(tx, sender, vmState, fork)
vmState.mutateStateDB:
db.subBalance(sender, tx.gasLimit.u256 * tx.gasPrice.u256)
execComputation(c)
if c.shouldBurnGas:
return tx.gasLimit
txRefundGas(tx, sender, c)
return tx.gasLimit - c.gasMeter.gasRemaining
proc asmSetupComputation(blockNumber: Uint256, chainDB: BaseChainDB, code,
data: seq[byte], forkOverride = none(Fork)): Computation =
let
parentNumber = blockNumber - 1
parent = chainDB.getBlockHeader(parentNumber)
header = chainDB.getBlockHeader(blockNumber)
headerHash = header.blockHash
body = chainDB.getBlockBody(headerHash)
vmState = newBaseVMState(parent.stateRoot, header, chainDB)
tx = body.transactions[0]
sender = transaction.getSender(tx)
gasLimit = 500000000
gasUsed = 0 #tx.payload.intrinsicGas.GasInt + gasFees[fork][GasTXCreate]
# This is an odd sort of test, where some fields are taken from
# `body.transactions[0]` but other fields (like `gasLimit`) are not. Also it
# creates the new contract using `code` like `CREATE`, but then executes the
# contract like it's `CALL`.
doAssert tx.isContractCreation
let contractAddress = generateAddress(sender, vmState.readOnlyStateDB.getNonce(sender))
vmState.mutateStateDB:
db.setCode(contractAddress, code)
return setupComputation(CallParams(
vmState: vmState,
forkOverride: forkOverride,
gasPrice: tx.gasPrice,
gasLimit: gasLimit - gasUsed,
sender: sender,
to: contractAddress,
isCreate: false,
value: tx.value,
input: data
))
type
AsmResult* = object
isSuccess*: bool
gasUsed*: GasInt
output*: seq[byte]
stack*: Stack
memory*: Memory
vmState*: BaseVMState
contractAddress*: EthAddress
proc asmCallEvm*(blockNumber: Uint256, chainDB: BaseChainDB, code, data: seq[byte], fork: Fork): AsmResult =
var c = asmSetupComputation(blockNumber, chainDB, code, data, some(fork))
let gas = c.gasMeter.gasRemaining
c.execComputation()
# Some of these are extra returned state, for testing, that a normal EVMC API
# computation doesn't return. We'll have to obtain them outside EVMC.
result.isSuccess = c.isSuccess
result.gasUsed = gas - c.gasMeter.gasRemaining
result.output = c.output
result.stack = c.stack
result.memory = c.memory
result.vmState = c.vmState
result.contractAddress = c.msg.contractAddress
proc fixtureSetupComputation(vmState: BaseVMState, call: RpcCallData,
origin: EthAddress, forkOverride = none(Fork)): Computation =
return setupComputation(CallParams(
vmState: vmState,
forkOverride: forkOverride,
origin: some(origin),
gasPrice: call.gasPrice,
gasLimit: call.gas, # Differs from `rpcSetupComputation`
sender: call.source,
to: call.to,
isCreate: call.contractCreation,
value: call.value,
input: call.data
))
type
FixtureResult* = object
isError*: bool
error*: Error
gasUsed*: GasInt
output*: seq[byte]
vmState*: BaseVMState
logEntries*: seq[Log]
proc fixtureCallEvm*(vmState: BaseVMState, call: RpcCallData,
origin: EthAddress, forkOverride = none(Fork)): FixtureResult =
var c = fixtureSetupComputation(vmState, call, origin, forkOverride)
let gas = c.gasMeter.gasRemaining
# Next line differs from all the other EVM calls. With `execComputation`,
# most "vm json tests" fail with either `balanceDiff` or `nonceDiff` errors.
c.executeOpcodes()
doAssert c.continuation.isNil
doAssert c.child.isNil
# Some of these are extra returned state, for testing, that a normal EVMC API
# computation doesn't return. We'll have to obtain them outside EVMC.
result.isError = c.isError
result.error = c.error
result.gasUsed = gas - c.gasMeter.gasRemaining
result.output = c.output
result.vmState = c.vmState
shallowCopy(result.logEntries, c.logEntries)