nimbus-eth1/nimbus/evm/interpreter_dispatch.nim

277 lines
7.9 KiB
Nim

# Nimbus
# Copyright (c) 2018-2024 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.
{.push raises: [].}
import
std/[macros, strformat],
pkg/[chronicles, chronos, stew/byteutils],
".."/[constants, db/ledger],
"."/[code_stream, computation, evm_errors],
"."/[message, precompiles, state, types],
./interpreter/op_dispatcher
logScope:
topics = "vm opcode"
# ------------------------------------------------------------------------------
# Private functions
# ------------------------------------------------------------------------------
proc runVM(
c: VmCpt,
fork: static EVMFork,
tracingEnabled: static bool,
): EvmResultVoid =
## VM instruction handler main loop - for each fork, a distinc version of
## this function is instantiated so that selection of fork-specific
## versions of functions happens only once
when tracingEnabled:
c.prepareTracer()
while true:
{.computedGoto.}
c.instr = c.code.next()
dispatchInstr(fork, tracingEnabled, c.instr, c)
ok()
macro selectVM(v: VmCpt, fork: EVMFork, tracingEnabled: bool): EvmResultVoid =
# Generate opcode dispatcher that calls selectVM with a literal for each fork:
#
# case fork
# of A: runVM(v, A, ...)
# ...
let caseStmt = nnkCaseStmt.newTree(fork)
for fork in EVMFork:
let
forkVal = quote:
`fork`
call = quote:
case `tracingEnabled`
of false: runVM(`v`, `fork`, false)
of true: runVM(`v`, `fork`, true)
caseStmt.add nnkOfBranch.newTree(forkVal, call)
caseStmt
proc beforeExecCall(c: Computation) =
c.snapshot()
if c.msg.kind == EVMC_CALL:
c.vmState.mutateStateDB:
db.subBalance(c.msg.sender, c.msg.value)
db.addBalance(c.msg.contractAddress, c.msg.value)
proc afterExecCall(c: Computation) =
## Collect all of the accounts that *may* need to be deleted based on EIP161
## https://github.com/ethereum/EIPs/blob/master/EIPS/eip-161.md
## also see: https://github.com/ethereum/EIPs/issues/716
if c.isError or c.fork >= FkByzantium:
if c.msg.contractAddress == RIPEMD_ADDR:
# Special case to account for geth+parity bug
c.vmState.stateDB.ripemdSpecial()
if c.isSuccess:
c.commit()
else:
c.rollback()
proc beforeExecCreate(c: Computation): bool =
c.vmState.mutateStateDB:
let nonce = db.getNonce(c.msg.sender)
if nonce + 1 < nonce:
let sender = c.msg.sender.toHex
c.setError(
"Nonce overflow when sender=" & sender & " wants to create contract", false
)
return true
db.setNonce(c.msg.sender, nonce + 1)
# We add this to the access list _before_ taking a snapshot.
# Even if the creation fails, the access-list change should not be rolled
# back EIP2929
if c.fork >= FkBerlin:
db.accessList(c.msg.contractAddress)
c.snapshot()
if c.vmState.readOnlyStateDB().contractCollision(c.msg.contractAddress):
let blurb = c.msg.contractAddress.toHex
c.setError("Address collision when creating contract address=" & blurb, true)
c.rollback()
return true
c.vmState.mutateStateDB:
db.subBalance(c.msg.sender, c.msg.value)
db.addBalance(c.msg.contractAddress, c.msg.value)
db.clearStorage(c.msg.contractAddress)
if c.fork >= FkSpurious:
# EIP161 nonce incrementation
db.incNonce(c.msg.contractAddress)
return false
proc afterExecCreate(c: Computation) =
if c.isSuccess:
# This can change `c.isSuccess`.
c.writeContract()
# Contract code should never be returned to the caller. Only data from
# `REVERT` is returned after a create. Clearing in this branch covers the
# right cases, particularly important with EVMC where it must be cleared.
if c.output.len > 0:
c.output = @[]
if c.isSuccess:
c.commit()
else:
c.rollback()
const MsgKindToOp: array[CallKind, Op] =
[Call, DelegateCall, CallCode, Create, Create2, EofCreate]
func msgToOp(msg: Message): Op =
if EVMC_STATIC in msg.flags:
return StaticCall
MsgKindToOp[msg.kind]
proc beforeExec(c: Computation): bool =
if c.msg.depth > 0:
c.vmState.captureEnter(
c,
msgToOp(c.msg),
c.msg.sender,
c.msg.contractAddress,
c.msg.data,
c.msg.gas,
c.msg.value,
)
if not c.msg.isCreate:
c.beforeExecCall()
false
else:
c.beforeExecCreate()
proc afterExec(c: Computation) =
if not c.msg.isCreate:
c.afterExecCall()
else:
c.afterExecCreate()
if c.msg.depth > 0:
let gasUsed = c.msg.gas - c.gasMeter.gasRemaining
c.vmState.captureExit(c, c.output, gasUsed, c.errorOpt)
# ------------------------------------------------------------------------------
# Public functions
# ------------------------------------------------------------------------------
template handleEvmError(x: EvmErrorObj) =
let
msg = $x.code
depth = $(c.msg.depth + 1) # plus one to match tracer depth, and avoid confusion
c.setError("Opcode Dispatch Error: " & msg & ", depth=" & depth, true)
proc executeOpcodes*(c: Computation) =
let fork = c.fork
block blockOne:
let cont = c.continuation
if cont.isNil:
let precompile = c.fork.getPrecompile(c.msg.codeAddress)
if precompile.isSome:
c.execPrecompile(precompile[])
break blockOne
else:
c.continuation = nil
cont().isOkOr:
handleEvmError(error)
break blockOne
let nextCont = c.continuation
if not nextCont.isNil:
# Return up to the caller, which will run the child
# and then call this proc again.
break blockOne
# traceOpCodeEnded is normally called directly after opcode execution
# but in the case that a continuation is created, it must run after that
# continuation has finished
if c.tracingEnabled:
c.traceOpCodeEnded(c.instr, c.opIndex)
if c.instr == Return or c.instr == Revert or c.instr == SelfDestruct:
break blockOne
c.selectVM(fork, c.tracingEnabled).isOkOr:
handleEvmError(error)
break blockOne # this break is not needed but make the flow clear
if c.isError() and c.continuation.isNil:
if c.tracingEnabled:
c.traceError()
when vm_use_recursion:
# Recursion with tiny stack frame per level.
proc execCallOrCreate*(c: Computation) =
if not c.beforeExec():
c.executeOpcodes()
while not c.continuation.isNil:
# If there's a continuation, then it's because there's either
# a child (i.e. call or create)
when evmc_enabled:
c.res = c.host.call(c.child[])
else:
execCallOrCreate(c.child)
c.child = nil
c.executeOpcodes()
c.afterExec()
c.dispose()
else:
proc execCallOrCreate*(cParam: Computation) =
var (c, before) = (cParam, true)
# No actual recursion, but simulate recursion including before/after/dispose.
while true:
while true:
if before and c.beforeExec():
break
c.executeOpcodes()
if c.continuation.isNil:
c.afterExec()
break
(before, c.child, c, c.parent) =
(true, nil.Computation, c.child, c)
if c.parent.isNil:
break
c.dispose()
(before, c.parent, c) =
(false, nil.Computation, c.parent)
while not c.isNil:
c.dispose()
c = c.parent
proc postExecComputation*(c: Computation) =
if c.isSuccess:
if c.fork < FkLondon:
# EIP-3529: Reduction in refunds
c.refundSelfDestruct()
c.vmState.status = c.isSuccess
# ------------------------------------------------------------------------------
# End
# ------------------------------------------------------------------------------