350 lines
11 KiB
Nim
350 lines
11 KiB
Nim
# Nimbus
|
|
# Copyright (c) 2018 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
|
|
chronicles, strformat, strutils, sequtils, macros, terminal, math, tables, options,
|
|
eth/[common, keys],
|
|
../constants, ../errors, ../validation, ../vm_state, ../vm_types,
|
|
./interpreter/[opcode_values, gas_meter, gas_costs, vm_forks],
|
|
./code_stream, ./memory, ./message, ./stack, ../db/[state_db, db_chain],
|
|
../utils/header, byteutils, ranges, precompiles,
|
|
transaction_tracer
|
|
|
|
logScope:
|
|
topics = "vm computation"
|
|
|
|
proc newBaseComputation*(vmState: BaseVMState, blockNumber: UInt256, message: Message, forkOverride=none(Fork)): BaseComputation =
|
|
new result
|
|
result.vmState = vmState
|
|
result.msg = message
|
|
result.memory = Memory()
|
|
result.stack = newStack()
|
|
result.gasMeter.init(message.gas)
|
|
result.children = @[]
|
|
result.accountsToDelete = initTable[EthAddress, EthAddress]()
|
|
result.code = newCodeStream(message.code)
|
|
# result.rawOutput = "0x"
|
|
result.gasCosts =
|
|
if forkOverride.isSome:
|
|
forkOverride.get.forkToSchedule
|
|
else:
|
|
blockNumber.toFork.forkToSchedule
|
|
result.forkOverride = forkOverride
|
|
|
|
proc isOriginComputation*(c: BaseComputation): bool =
|
|
# Is this computation the computation initiated by a transaction
|
|
c.msg.isOrigin
|
|
|
|
template isSuccess*(c: BaseComputation): bool =
|
|
c.error.isNil
|
|
|
|
template isError*(c: BaseComputation): bool =
|
|
not c.isSuccess
|
|
|
|
func shouldBurnGas*(c: BaseComputation): bool =
|
|
c.isError and c.error.burnsGas
|
|
|
|
func shouldEraseReturnData*(c: BaseComputation): bool =
|
|
c.isError and c.error.erasesReturnData
|
|
|
|
func bytesToHex(x: openarray[byte]): string {.inline.} =
|
|
## TODO: use seq[byte] for raw data and delete this proc
|
|
foldl(x, a & b.int.toHex(2).toLowerAscii, "0x")
|
|
|
|
func output*(c: BaseComputation): seq[byte] =
|
|
if c.shouldEraseReturnData:
|
|
@[]
|
|
else:
|
|
c.rawOutput
|
|
|
|
func `output=`*(c: var BaseComputation, value: openarray[byte]) =
|
|
c.rawOutput = @value
|
|
|
|
proc outputHex*(c: BaseComputation): string =
|
|
if c.shouldEraseReturnData:
|
|
return "0x"
|
|
c.rawOutput.bytesToHex
|
|
|
|
proc prepareChildMessage*(
|
|
c: var BaseComputation,
|
|
gas: GasInt,
|
|
to: EthAddress,
|
|
value: UInt256,
|
|
data: seq[byte],
|
|
code: seq[byte],
|
|
options: MessageOptions = newMessageOptions()): Message =
|
|
|
|
var childOptions = options
|
|
childOptions.depth = c.msg.depth + 1
|
|
result = newMessage(
|
|
gas,
|
|
c.msg.gasPrice,
|
|
to,
|
|
c.msg.origin,
|
|
value,
|
|
data,
|
|
code,
|
|
childOptions)
|
|
|
|
type
|
|
ComputationSnapshot* = object
|
|
snapshot: Snapshot
|
|
computation: BaseComputation
|
|
|
|
proc snapshot*(computation: BaseComputation): ComputationSnapshot =
|
|
result.snapshot = computation.vmState.snapshot()
|
|
result.computation = computation
|
|
|
|
proc revert*(snapshot: var ComputationSnapshot, burnsGas: bool = false) =
|
|
snapshot.snapshot.revert()
|
|
snapshot.computation.error = Error(info: getCurrentExceptionMsg(), burnsGas: burnsGas)
|
|
|
|
proc commit*(snapshot: var ComputationSnapshot) {.inline.} =
|
|
snapshot.snapshot.commit()
|
|
|
|
proc dispose*(snapshot: var ComputationSnapshot) {.inline.} =
|
|
snapshot.snapshot.dispose()
|
|
|
|
proc applyMessageAux(computation: var BaseComputation, opCode: static[Op]) =
|
|
if computation.msg.depth > STACK_DEPTH_LIMIT:
|
|
raise newException(StackDepthError, "Stack depth limit reached")
|
|
|
|
if computation.msg.value != 0:
|
|
let senderBalance =
|
|
computation.vmState.readOnlyStateDb().
|
|
getBalance(computation.msg.sender)
|
|
var newBalance = senderBalance
|
|
|
|
if senderBalance < computation.msg.value:
|
|
raise newException(InsufficientFunds,
|
|
&"Insufficient funds: {senderBalance} < {computation.msg.value}"
|
|
)
|
|
|
|
let
|
|
insufficientFunds = senderBalance < computation.msg.value
|
|
stackTooDeep = computation.msg.depth >= MaxCallDepth
|
|
|
|
if insufficientFunds or stackTooDeep:
|
|
computation.returnData = @[]
|
|
var errMessage: string
|
|
if insufficientFunds:
|
|
errMessage = &"Insufficient Funds: have: {$senderBalance} need: {$computation.msg.value}"
|
|
elif stackTooDeep:
|
|
errMessage = "Stack Limit Reached"
|
|
else:
|
|
raise newException(VMError, "Invariant: Unreachable code path")
|
|
|
|
debug "Computation failure", msg = errMessage
|
|
computation.gasMeter.returnGas(computation.msg.gas)
|
|
push: 0
|
|
return
|
|
|
|
newBalance = senderBalance - computation.msg.value
|
|
computation.vmState.mutateStateDb:
|
|
db.setBalance(computation.msg.sender, newBalance)
|
|
db.addBalance(computation.msg.storageAddress, computation.msg.value)
|
|
|
|
trace "Value transferred",
|
|
source = computation.msg.sender,
|
|
dest = computation.msg.storageAddress,
|
|
value = computation.msg.value,
|
|
oldSenderBalance = senderBalance,
|
|
newSenderBalance = newBalance,
|
|
gasPrice = computation.msg.gasPrice,
|
|
gas = computation.msg.gas
|
|
|
|
trace "Apply message",
|
|
value = computation.msg.value,
|
|
senderBalance = newBalance,
|
|
sender = computation.msg.sender.toHex,
|
|
address = computation.msg.storageAddress.toHex,
|
|
gasPrice = computation.msg.gasPrice,
|
|
gas = computation.msg.gas
|
|
else:
|
|
# even though the value is zero, the account
|
|
# should be exist.
|
|
computation.vmState.mutateStateDb:
|
|
db.addBalance(computation.msg.storageAddress, computation.msg.value)
|
|
|
|
proc applyMessage(computation: var BaseComputation, opCode: static[Op]) =
|
|
var snapshot = computation.snapshot()
|
|
defer: snapshot.dispose()
|
|
|
|
when opCode in {Call, Create}:
|
|
try:
|
|
computation.applyMessageAux(opCode)
|
|
except VMError:
|
|
snapshot.revert()
|
|
debug "applyMessageAux failed", msg = computation.error.info
|
|
return
|
|
|
|
if computation.gasMeter.gasRemaining < 0:
|
|
snapshot.commit()
|
|
return
|
|
|
|
try:
|
|
# Run code
|
|
# We cannot use the normal dispatching function `executeOpcodes`
|
|
# within `interpreter_dispatch.nim` due to a cyclic dependency.
|
|
if not computation.execPrecompiles:
|
|
computation.opcodeExec(computation)
|
|
snapshot.commit()
|
|
except VMError:
|
|
snapshot.revert(true)
|
|
debug "VMError applyMessage failed",
|
|
msg = computation.error.info,
|
|
depth = computation.msg.depth
|
|
except EVMError:
|
|
snapshot.revert() # TODO: true or false?
|
|
debug "EVMError applyMessage failed",
|
|
msg = computation.error.info,
|
|
depth = computation.msg.depth
|
|
|
|
proc applyCreateMessage(fork: Fork, computation: var BaseComputation, opCode: static[Op]) =
|
|
computation.applyMessage(opCode)
|
|
if computation.isError: return
|
|
|
|
let contractCode = computation.output
|
|
if contractCode.len == 0: return
|
|
|
|
var snapshot = computation.snapshot()
|
|
defer: snapshot.dispose()
|
|
|
|
if fork >= FkSpurious and contractCode.len >= EIP170_CODE_SIZE_LIMIT:
|
|
raise newException(OutOfGas, &"Contract code size exceeds EIP170 limit of {EIP170_CODE_SIZE_LIMIT}. Got code of size: {contractCode.len}")
|
|
|
|
try:
|
|
# tricky gasCost: 1,0,0 -> createCost. 0,0,x -> depositCost
|
|
let gasCost = computation.gasCosts[Create].m_handler(0, 0, contractCode.len)
|
|
computation.gasMeter.consumeGas(gasCost,
|
|
reason = "Write contract code for CREATE")
|
|
|
|
let storageAddr = computation.msg.storageAddress
|
|
trace "SETTING CODE",
|
|
address = storageAddr.toHex,
|
|
length = len(contract_code),
|
|
hash = contractCode.rlpHash
|
|
|
|
computation.vmState.mutateStateDb:
|
|
db.setCode(storageAddr, contractCode.toRange)
|
|
|
|
snapshot.commit()
|
|
except OutOfGas:
|
|
debug "applyCreateMessage failed: ",
|
|
msg = getCurrentExceptionMsg(),
|
|
depth = computation.msg.depth
|
|
if fork < FkHomestead:
|
|
computation.output = @[]
|
|
else:
|
|
# Different from Frontier:
|
|
# Reverts state on gas failure while writing contract code.
|
|
snapshot.revert()
|
|
|
|
proc generateChildComputation*(fork: Fork, computation: var BaseComputation, childMsg: Message, opCode: static[Op]): BaseComputation =
|
|
var childComp = newBaseComputation(
|
|
computation.vmState,
|
|
computation.vmState.blockNumber,
|
|
childMsg,
|
|
some(fork))
|
|
|
|
# Copy the fork op code executor proc (assumes child computation is in the same fork)
|
|
childComp.opCodeExec = computation.opCodeExec
|
|
|
|
if childMsg.isCreate:
|
|
fork.applyCreateMessage(childComp, opCode)
|
|
else:
|
|
applyMessage(childComp, opCode)
|
|
|
|
return childComp
|
|
|
|
proc addChildComputation(fork: Fork, computation: var BaseComputation, child: BaseComputation) =
|
|
if child.isError:
|
|
if child.msg.isCreate:
|
|
computation.returnData = child.output
|
|
elif child.shouldBurnGas:
|
|
computation.returnData = @[]
|
|
else:
|
|
computation.returnData = child.output
|
|
else:
|
|
if child.msg.isCreate:
|
|
computation.returnData = @[]
|
|
else:
|
|
computation.returnData = child.output
|
|
for k, v in child.accountsToDelete:
|
|
computation.accountsToDelete[k] = v
|
|
computation.children.add(child)
|
|
|
|
proc getFork*(computation: BaseComputation): Fork =
|
|
result =
|
|
if computation.forkOverride.isSome:
|
|
computation.forkOverride.get
|
|
else:
|
|
computation.vmState.blockNumber.toFork
|
|
|
|
proc applyChildComputation*(computation: var BaseComputation, childMsg: Message, opCode: static[Op]): BaseComputation =
|
|
## Apply the vm message childMsg as a child computation.
|
|
let fork = computation.getFork
|
|
result = fork.generateChildComputation(computation, childMsg, opCode)
|
|
fork.addChildComputation(computation, result)
|
|
|
|
proc registerAccountForDeletion*(c: var BaseComputation, beneficiary: EthAddress) =
|
|
if c.msg.storageAddress in c.accountsToDelete:
|
|
raise newException(ValueError,
|
|
"invariant: should be impossible for an account to be " &
|
|
"registered for deletion multiple times")
|
|
c.accountsToDelete[c.msg.storageAddress] = beneficiary
|
|
|
|
proc isSuicided*(c: var BaseComputation, address: EthAddress): bool =
|
|
result = address in c.accountsToDelete
|
|
|
|
proc addLogEntry*(c: var BaseComputation, log: Log) {.inline.} =
|
|
c.vmState.addLogEntry(log)
|
|
|
|
# many methods are basically TODO, but they still return valid values
|
|
# in order to test some existing code
|
|
func getAccountsForDeletion*(c: BaseComputation): seq[EthAddress] =
|
|
# TODO
|
|
if c.isError:
|
|
result = @[]
|
|
else:
|
|
result = @[]
|
|
for account in c.accountsToDelete.keys:
|
|
result.add(account)
|
|
|
|
proc getGasRefund*(c: BaseComputation): GasInt =
|
|
if c.isError:
|
|
result = 0
|
|
else:
|
|
result = c.gasMeter.gasRefunded + c.children.mapIt(it.getGasRefund()).foldl(a + b, 0'i64)
|
|
|
|
proc getGasUsed*(c: BaseComputation): GasInt =
|
|
if c.shouldBurnGas:
|
|
result = c.msg.gas
|
|
else:
|
|
result = max(0, c.msg.gas - c.gasMeter.gasRemaining)
|
|
|
|
proc getGasRemaining*(c: BaseComputation): GasInt =
|
|
if c.shouldBurnGas:
|
|
result = 0
|
|
else:
|
|
result = c.gasMeter.gasRemaining
|
|
|
|
proc tracingEnabled*(c: BaseComputation): bool =
|
|
c.vmState.tracingEnabled
|
|
|
|
proc traceOpCodeStarted*(c: BaseComputation, op: Op): int =
|
|
c.vmState.tracer.traceOpCodeStarted(c, op)
|
|
|
|
proc traceOpCodeEnded*(c: BaseComputation, op: Op, lastIndex: int) =
|
|
c.vmState.tracer.traceOpCodeEnded(c, op, lastIndex)
|
|
|
|
proc traceError*(c: BaseComputation) =
|
|
c.vmState.tracer.traceError(c)
|
|
|
|
proc prepareTracer*(c: BaseComputation) =
|
|
c.vmState.tracer.prepare(c.msg.depth)
|