lotus/chain/vm/fvm.go

650 lines
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package vm
import (
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"bytes"
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"context"
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"fmt"
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"io"
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"os"
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"sort"
"sync"
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"time"
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"github.com/ipfs/go-cid"
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cbor "github.com/ipfs/go-ipld-cbor"
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cbg "github.com/whyrusleeping/cbor-gen"
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"golang.org/x/xerrors"
ffi "github.com/filecoin-project/filecoin-ffi"
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ffi_cgo "github.com/filecoin-project/filecoin-ffi/cgo"
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"github.com/filecoin-project/go-address"
"github.com/filecoin-project/go-state-types/abi"
"github.com/filecoin-project/go-state-types/exitcode"
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"github.com/filecoin-project/lotus/blockstore"
"github.com/filecoin-project/lotus/build"
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"github.com/filecoin-project/lotus/chain/actors"
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"github.com/filecoin-project/lotus/chain/actors/adt"
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"github.com/filecoin-project/lotus/chain/actors/aerrors"
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"github.com/filecoin-project/lotus/chain/actors/builtin/miner"
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"github.com/filecoin-project/lotus/chain/actors/policy"
"github.com/filecoin-project/lotus/chain/state"
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"github.com/filecoin-project/lotus/chain/types"
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"github.com/filecoin-project/lotus/lib/sigs"
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"github.com/filecoin-project/lotus/node/bundle"
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)
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var _ Interface = (*FVM)(nil)
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var _ ffi_cgo.Externs = (*FvmExtern)(nil)
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var debugBundleV8path = os.Getenv("LOTUS_FVM_DEBUG_BUNDLE_V8")
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type FvmExtern struct {
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Rand
blockstore.Blockstore
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epoch abi.ChainEpoch
lbState LookbackStateGetter
base cid.Cid
}
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// This may eventually become identical to ExecutionTrace, but we can make incremental progress towards that
type FvmExecutionTrace struct {
Msg *types.Message
MsgRct *types.MessageReceipt
Error string
Subcalls []FvmExecutionTrace
}
func (t *FvmExecutionTrace) ToExecutionTrace() types.ExecutionTrace {
if t == nil {
return types.ExecutionTrace{}
}
ret := types.ExecutionTrace{
Msg: t.Msg,
MsgRct: t.MsgRct,
Error: t.Error,
Subcalls: nil, // Should be nil when there are no subcalls for backwards compatibility
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}
if len(t.Subcalls) > 0 {
ret.Subcalls = make([]types.ExecutionTrace, len(t.Subcalls))
for i, v := range t.Subcalls {
ret.Subcalls[i] = v.ToExecutionTrace()
}
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}
return ret
}
// VerifyConsensusFault is similar to the one in syscalls.go used by the Lotus VM, except it never errors
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// Errors are logged and "no fault" is returned, which is functionally what go-actors does anyway
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func (x *FvmExtern) VerifyConsensusFault(ctx context.Context, a, b, extra []byte) (*ffi_cgo.ConsensusFault, int64) {
totalGas := int64(0)
ret := &ffi_cgo.ConsensusFault{
Type: ffi_cgo.ConsensusFaultNone,
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}
// Note that block syntax is not validated. Any validly signed block will be accepted pursuant to the below conditions.
// Whether or not it could ever have been accepted in a chain is not checked/does not matter here.
// for that reason when checking block parent relationships, rather than instantiating a Tipset to do so
// (which runs a syntactic check), we do it directly on the CIDs.
// (0) cheap preliminary checks
// can blocks be decoded properly?
var blockA, blockB types.BlockHeader
if decodeErr := blockA.UnmarshalCBOR(bytes.NewReader(a)); decodeErr != nil {
log.Info("invalid consensus fault: cannot decode first block header: %w", decodeErr)
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return ret, totalGas
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}
if decodeErr := blockB.UnmarshalCBOR(bytes.NewReader(b)); decodeErr != nil {
log.Info("invalid consensus fault: cannot decode second block header: %w", decodeErr)
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return ret, totalGas
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}
// are blocks the same?
if blockA.Cid().Equals(blockB.Cid()) {
log.Info("invalid consensus fault: submitted blocks are the same")
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return ret, totalGas
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}
// (1) check conditions necessary to any consensus fault
// were blocks mined by same miner?
if blockA.Miner != blockB.Miner {
log.Info("invalid consensus fault: blocks not mined by the same miner")
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return ret, totalGas
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}
// block a must be earlier or equal to block b, epoch wise (ie at least as early in the chain).
if blockB.Height < blockA.Height {
log.Info("invalid consensus fault: first block must not be of higher height than second")
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return ret, totalGas
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}
ret.Epoch = blockB.Height
faultType := ffi_cgo.ConsensusFaultNone
// (2) check for the consensus faults themselves
// (a) double-fork mining fault
if blockA.Height == blockB.Height {
faultType = ffi_cgo.ConsensusFaultDoubleForkMining
}
// (b) time-offset mining fault
// strictly speaking no need to compare heights based on double fork mining check above,
// but at same height this would be a different fault.
if types.CidArrsEqual(blockA.Parents, blockB.Parents) && blockA.Height != blockB.Height {
faultType = ffi_cgo.ConsensusFaultTimeOffsetMining
}
// (c) parent-grinding fault
// Here extra is the "witness", a third block that shows the connection between A and B as
// A's sibling and B's parent.
// Specifically, since A is of lower height, it must be that B was mined omitting A from its tipset
//
// B
// |
// [A, C]
var blockC types.BlockHeader
if len(extra) > 0 {
if decodeErr := blockC.UnmarshalCBOR(bytes.NewReader(extra)); decodeErr != nil {
log.Info("invalid consensus fault: cannot decode extra: %w", decodeErr)
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return ret, totalGas
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}
if types.CidArrsEqual(blockA.Parents, blockC.Parents) && blockA.Height == blockC.Height &&
types.CidArrsContains(blockB.Parents, blockC.Cid()) && !types.CidArrsContains(blockB.Parents, blockA.Cid()) {
faultType = ffi_cgo.ConsensusFaultParentGrinding
}
}
// (3) return if no consensus fault by now
if faultType == ffi_cgo.ConsensusFaultNone {
log.Info("invalid consensus fault: no fault detected")
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return ret, totalGas
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}
// else
// (4) expensive final checks
// check blocks are properly signed by their respective miner
// note we do not need to check extra's: it is a parent to block b
// which itself is signed, so it was willingly included by the miner
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gasA, sigErr := x.VerifyBlockSig(ctx, &blockA)
totalGas += gasA
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if sigErr != nil {
log.Info("invalid consensus fault: cannot verify first block sig: %w", sigErr)
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return ret, totalGas
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}
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gas2, sigErr := x.VerifyBlockSig(ctx, &blockB)
totalGas += gas2
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if sigErr != nil {
log.Info("invalid consensus fault: cannot verify second block sig: %w", sigErr)
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return ret, totalGas
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}
ret.Type = faultType
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ret.Target = blockA.Miner
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return ret, totalGas
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}
func (x *FvmExtern) VerifyBlockSig(ctx context.Context, blk *types.BlockHeader) (int64, error) {
waddr, gasUsed, err := x.workerKeyAtLookback(ctx, blk.Miner, blk.Height)
if err != nil {
return gasUsed, err
}
return gasUsed, sigs.CheckBlockSignature(ctx, blk, waddr)
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}
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func (x *FvmExtern) workerKeyAtLookback(ctx context.Context, minerId address.Address, height abi.ChainEpoch) (address.Address, int64, error) {
if height < x.epoch-policy.ChainFinality {
return address.Undef, 0, xerrors.Errorf("cannot get worker key (currEpoch %d, height %d)", x.epoch, height)
}
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gasUsed := int64(0)
gasAdder := func(gc GasCharge) {
// technically not overflow safe, but that's fine
gasUsed += gc.Total()
}
cstWithoutGas := cbor.NewCborStore(x.Blockstore)
cbb := &gasChargingBlocks{gasAdder, PricelistByEpoch(x.epoch), x.Blockstore}
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cstWithGas := cbor.NewCborStore(cbb)
lbState, err := x.lbState(ctx, height)
if err != nil {
return address.Undef, gasUsed, err
}
// get appropriate miner actor
act, err := lbState.GetActor(minerId)
if err != nil {
return address.Undef, gasUsed, err
}
// use that to get the miner state
mas, err := miner.Load(adt.WrapStore(ctx, cstWithGas), act)
if err != nil {
return address.Undef, gasUsed, err
}
info, err := mas.Info()
if err != nil {
return address.Undef, gasUsed, err
}
stateTree, err := state.LoadStateTree(cstWithoutGas, x.base)
if err != nil {
return address.Undef, gasUsed, err
}
raddr, err := ResolveToKeyAddr(stateTree, cstWithGas, info.Worker)
if err != nil {
return address.Undef, gasUsed, err
}
return raddr, gasUsed, nil
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}
type FVM struct {
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fvm *ffi.FVM
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}
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func defaultFVMOpts(ctx context.Context, opts *VMOpts) (*ffi.FVMOpts, error) {
state, err := state.LoadStateTree(cbor.NewCborStore(opts.Bstore), opts.StateBase)
if err != nil {
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return nil, xerrors.Errorf("loading state tree: %w", err)
}
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circToReport, err := opts.CircSupplyCalc(ctx, opts.Epoch, state)
if err != nil {
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return nil, xerrors.Errorf("calculating circ supply: %w", err)
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}
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return &ffi.FVMOpts{
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FVMVersion: 0,
Externs: &FvmExtern{
Rand: opts.Rand,
Blockstore: opts.Bstore,
lbState: opts.LookbackState,
base: opts.StateBase,
epoch: opts.Epoch,
},
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Epoch: opts.Epoch,
BaseFee: opts.BaseFee,
BaseCircSupply: circToReport,
NetworkVersion: opts.NetworkVersion,
StateBase: opts.StateBase,
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Tracing: EnableDetailedTracing,
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}, nil
}
func NewFVM(ctx context.Context, opts *VMOpts) (*FVM, error) {
fvmOpts, err := defaultFVMOpts(ctx, opts)
if err != nil {
return nil, xerrors.Errorf("creating fvm opts: %w", err)
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}
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if os.Getenv("LOTUS_USE_FVM_CUSTOM_BUNDLE") == "1" {
av, err := actors.VersionForNetwork(opts.NetworkVersion)
if err != nil {
return nil, xerrors.Errorf("mapping network version to actors version: %w", err)
}
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c, ok := actors.GetManifest(av)
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if !ok {
return nil, xerrors.Errorf("no manifest for custom bundle (actors version %d)", av)
}
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fvmOpts.Manifest = c
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}
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fvm, err := ffi.CreateFVM(fvmOpts)
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if err != nil {
return nil, err
}
return &FVM{
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fvm: fvm,
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}, nil
}
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func NewDebugFVM(ctx context.Context, opts *VMOpts) (*FVM, error) {
baseBstore := opts.Bstore
overlayBstore := blockstore.NewMemorySync()
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cborStore := cbor.NewCborStore(overlayBstore)
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vmBstore := blockstore.NewTieredBstore(overlayBstore, baseBstore)
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opts.Bstore = vmBstore
fvmOpts, err := defaultFVMOpts(ctx, opts)
if err != nil {
return nil, xerrors.Errorf("creating fvm opts: %w", err)
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}
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fvmOpts.Debug = true
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putMapping := func(ar map[cid.Cid]cid.Cid) (cid.Cid, error) {
var mapping xMapping
mapping.redirects = make([]xRedirect, 0, len(ar))
for from, to := range ar {
mapping.redirects = append(mapping.redirects, xRedirect{from: from, to: to})
}
sort.Slice(mapping.redirects, func(i, j int) bool {
return bytes.Compare(mapping.redirects[i].from.Bytes(), mapping.redirects[j].from.Bytes()) < 0
})
// Passing this as a pointer of structs has proven to be an enormous PiTA; hence this code.
mappingCid, err := cborStore.Put(context.TODO(), &mapping)
if err != nil {
return cid.Undef, err
}
return mappingCid, nil
}
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createMapping := func(debugBundlePath string) error {
mfCid, err := bundle.LoadBundleFromFile(ctx, overlayBstore, debugBundlePath)
if err != nil {
return xerrors.Errorf("loading debug bundle: %w", err)
}
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mf, err := actors.LoadManifest(ctx, mfCid, adt.WrapStore(ctx, cborStore))
if err != nil {
return xerrors.Errorf("loading debug manifest: %w", err)
}
// create actor redirect mapping
actorRedirect := make(map[cid.Cid]cid.Cid)
for _, key := range actors.GetBuiltinActorsKeys() {
from, ok := actors.GetActorCodeID(actors.Version8, key)
if !ok {
log.Warnf("actor missing in the from manifest %s", key)
continue
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}
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to, ok := mf.Get(key)
if !ok {
log.Warnf("actor missing in the to manifest %s", key)
continue
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}
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actorRedirect[from] = to
}
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if len(actorRedirect) > 0 {
mappingCid, err := putMapping(actorRedirect)
if err != nil {
return xerrors.Errorf("error writing redirect mapping: %w", err)
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}
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fvmOpts.ActorRedirect = mappingCid
}
return nil
}
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av, err := actors.VersionForNetwork(opts.NetworkVersion)
if err != nil {
return nil, xerrors.Errorf("error determining actors version for network version %d: %w", opts.NetworkVersion, err)
}
switch av {
case actors.Version8:
if debugBundleV8path != "" {
if err := createMapping(debugBundleV8path); err != nil {
log.Errorf("failed to create v8 debug mapping")
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}
}
}
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fvm, err := ffi.CreateFVM(fvmOpts)
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if err != nil {
return nil, err
}
return &FVM{
fvm: fvm,
}, nil
}
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func (vm *FVM) ApplyMessage(ctx context.Context, cmsg types.ChainMsg) (*ApplyRet, error) {
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start := build.Clock.Now()
vmMsg := cmsg.VMMessage()
msgBytes, err := vmMsg.Serialize()
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if err != nil {
return nil, xerrors.Errorf("serializing msg: %w", err)
}
ret, err := vm.fvm.ApplyMessage(msgBytes, uint(cmsg.ChainLength()))
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if err != nil {
return nil, xerrors.Errorf("applying msg: %w", err)
}
duration := time.Since(start)
receipt := types.MessageReceipt{
Return: ret.Return,
ExitCode: exitcode.ExitCode(ret.ExitCode),
GasUsed: ret.GasUsed,
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}
var aerr aerrors.ActorError
if ret.ExitCode != 0 {
amsg := ret.FailureInfo
if amsg == "" {
amsg = "unknown error"
}
aerr = aerrors.New(exitcode.ExitCode(ret.ExitCode), amsg)
}
var et types.ExecutionTrace
if len(ret.ExecTraceBytes) != 0 {
var fvmEt FvmExecutionTrace
if err = fvmEt.UnmarshalCBOR(bytes.NewReader(ret.ExecTraceBytes)); err != nil {
return nil, xerrors.Errorf("failed to unmarshal exectrace: %w", err)
}
et = fvmEt.ToExecutionTrace()
}
// Set the top-level exectrace info from the message and receipt for backwards compatibility
et.Msg = vmMsg
et.MsgRct = &receipt
et.Duration = duration
if aerr != nil {
et.Error = aerr.Error()
}
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return &ApplyRet{
MessageReceipt: receipt,
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GasCosts: &GasOutputs{
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BaseFeeBurn: ret.BaseFeeBurn,
OverEstimationBurn: ret.OverEstimationBurn,
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MinerPenalty: ret.MinerPenalty,
MinerTip: ret.MinerTip,
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Refund: ret.Refund,
GasRefund: ret.GasRefund,
GasBurned: ret.GasBurned,
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},
ActorErr: aerr,
ExecutionTrace: et,
Duration: duration,
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}, nil
}
func (vm *FVM) ApplyImplicitMessage(ctx context.Context, cmsg *types.Message) (*ApplyRet, error) {
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start := build.Clock.Now()
vmMsg := cmsg.VMMessage()
msgBytes, err := vmMsg.Serialize()
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if err != nil {
return nil, xerrors.Errorf("serializing msg: %w", err)
}
ret, err := vm.fvm.ApplyImplicitMessage(msgBytes)
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if err != nil {
return nil, xerrors.Errorf("applying msg: %w", err)
}
duration := time.Since(start)
receipt := types.MessageReceipt{
Return: ret.Return,
ExitCode: exitcode.ExitCode(ret.ExitCode),
GasUsed: ret.GasUsed,
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}
var aerr aerrors.ActorError
if ret.ExitCode != 0 {
amsg := ret.FailureInfo
if amsg == "" {
amsg = "unknown error"
}
aerr = aerrors.New(exitcode.ExitCode(ret.ExitCode), amsg)
}
var et types.ExecutionTrace
if len(ret.ExecTraceBytes) != 0 {
var fvmEt FvmExecutionTrace
if err = fvmEt.UnmarshalCBOR(bytes.NewReader(ret.ExecTraceBytes)); err != nil {
return nil, xerrors.Errorf("failed to unmarshal exectrace: %w", err)
}
et = fvmEt.ToExecutionTrace()
} else {
et.Msg = vmMsg
et.MsgRct = &receipt
et.Duration = duration
if aerr != nil {
et.Error = aerr.Error()
}
}
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applyRet := &ApplyRet{
MessageReceipt: receipt,
ActorErr: aerr,
ExecutionTrace: et,
Duration: duration,
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}
if ret.ExitCode != 0 {
return applyRet, fmt.Errorf("implicit message failed with exit code: %d and error: %w", ret.ExitCode, applyRet.ActorErr)
}
return applyRet, nil
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}
func (vm *FVM) Flush(ctx context.Context) (cid.Cid, error) {
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return vm.fvm.Flush()
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}
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type dualExecutionFVM struct {
main *FVM
debug *FVM
}
var _ Interface = (*dualExecutionFVM)(nil)
func NewDualExecutionFVM(ctx context.Context, opts *VMOpts) (Interface, error) {
main, err := NewFVM(ctx, opts)
if err != nil {
return nil, err
}
debug, err := NewDebugFVM(ctx, opts)
if err != nil {
return nil, err
}
return &dualExecutionFVM{
main: main,
debug: debug,
}, nil
}
func (vm *dualExecutionFVM) ApplyMessage(ctx context.Context, cmsg types.ChainMsg) (ret *ApplyRet, err error) {
var wg sync.WaitGroup
wg.Add(2)
go func() {
defer wg.Done()
ret, err = vm.main.ApplyMessage(ctx, cmsg)
}()
go func() {
defer wg.Done()
if _, err := vm.debug.ApplyMessage(ctx, cmsg); err != nil {
log.Errorf("debug execution failed: %w", err)
}
}()
wg.Wait()
return ret, err
}
func (vm *dualExecutionFVM) ApplyImplicitMessage(ctx context.Context, msg *types.Message) (ret *ApplyRet, err error) {
var wg sync.WaitGroup
wg.Add(2)
go func() {
defer wg.Done()
ret, err = vm.main.ApplyImplicitMessage(ctx, msg)
}()
go func() {
defer wg.Done()
if _, err := vm.debug.ApplyImplicitMessage(ctx, msg); err != nil {
log.Errorf("debug execution failed: %s", err)
}
}()
wg.Wait()
return ret, err
}
func (vm *dualExecutionFVM) Flush(ctx context.Context) (cid.Cid, error) {
return vm.main.Flush(ctx)
}
// Passing this as a pointer of structs has proven to be an enormous PiTA; hence this code.
type xRedirect struct{ from, to cid.Cid }
type xMapping struct{ redirects []xRedirect }
func (m *xMapping) MarshalCBOR(w io.Writer) error {
scratch := make([]byte, 9)
if err := cbg.WriteMajorTypeHeaderBuf(scratch, w, cbg.MajArray, uint64(len(m.redirects))); err != nil {
return err
}
for _, v := range m.redirects {
if err := v.MarshalCBOR(w); err != nil {
return err
}
}
return nil
}
func (r *xRedirect) MarshalCBOR(w io.Writer) error {
scratch := make([]byte, 9)
if err := cbg.WriteMajorTypeHeaderBuf(scratch, w, cbg.MajArray, uint64(2)); err != nil {
return err
}
if err := cbg.WriteCidBuf(scratch, w, r.from); err != nil {
return xerrors.Errorf("failed to write cid field from: %w", err)
}
if err := cbg.WriteCidBuf(scratch, w, r.to); err != nil {
return xerrors.Errorf("failed to write cid field from: %w", err)
}
return nil
}