package vm import ( "bytes" "encoding/hex" "fmt" "reflect" "github.com/ipfs/go-cid" cbg "github.com/whyrusleeping/cbor-gen" "golang.org/x/xerrors" "github.com/filecoin-project/lotus/chain/actors" "github.com/filecoin-project/lotus/chain/actors/aerrors" "github.com/filecoin-project/lotus/chain/types" ) type invoker struct { builtInCode map[cid.Cid]nativeCode builtInState map[cid.Cid]reflect.Type } type invokeFunc func(act *types.Actor, vmctx types.VMContext, params []byte) ([]byte, aerrors.ActorError) type nativeCode []invokeFunc func newInvoker() *invoker { inv := &invoker{ builtInCode: make(map[cid.Cid]nativeCode), builtInState: make(map[cid.Cid]reflect.Type), } // add builtInCode using: register(cid, singleton) inv.register(actors.InitCodeCid, actors.InitActor{}, actors.InitActorState{}) inv.register(actors.CronCodeCid, actors.CronActor{}, actors.CronActorState{}) inv.register(actors.StoragePowerCodeCid, actors.StoragePowerActor{}, actors.StoragePowerState{}) inv.register(actors.StorageMarketCodeCid, actors.StorageMarketActor{}, actors.StorageMarketState{}) inv.register(actors.StorageMinerCodeCid, actors.StorageMinerActor{}, actors.StorageMinerActorState{}) inv.register(actors.MultisigCodeCid, actors.MultiSigActor{}, actors.MultiSigActorState{}) inv.register(actors.PaymentChannelCodeCid, actors.PaymentChannelActor{}, actors.PaymentChannelActorState{}) return inv } func (inv *invoker) Invoke(act *types.Actor, vmctx types.VMContext, method uint64, params []byte) ([]byte, aerrors.ActorError) { if act.Code == actors.AccountCodeCid { return nil, aerrors.Newf(254, "cannot invoke methods on account actors") } code, ok := inv.builtInCode[act.Code] if !ok { log.Errorf("no code for actor %s (Addr: %s)", act.Code, vmctx.Message().To) return nil, aerrors.Newf(255, "no code for actor %s(%d)(%s)", act.Code, method, hex.EncodeToString(params)) } if method >= uint64(len(code)) || code[method] == nil { return nil, aerrors.Newf(255, "no method %d on actor", method) } return code[method](act, vmctx, params) } func (inv *invoker) register(c cid.Cid, instance Invokee, state interface{}) { code, err := inv.transform(instance) if err != nil { panic(err) } inv.builtInCode[c] = code inv.builtInState[c] = reflect.TypeOf(state) } type Invokee interface { Exports() []interface{} } var tVMContext = reflect.TypeOf((*types.VMContext)(nil)).Elem() var tAError = reflect.TypeOf((*aerrors.ActorError)(nil)).Elem() func (*invoker) transform(instance Invokee) (nativeCode, error) { itype := reflect.TypeOf(instance) exports := instance.Exports() for i, m := range exports { i := i newErr := func(format string, args ...interface{}) error { str := fmt.Sprintf(format, args...) return fmt.Errorf("transform(%s) export(%d): %s", itype.Name(), i, str) } if m == nil { continue } meth := reflect.ValueOf(m) t := meth.Type() if t.Kind() != reflect.Func { return nil, newErr("is not a function") } if t.NumIn() != 3 { return nil, newErr("wrong number of inputs should be: " + "*types.Actor, *VMContext, ") } if t.In(0) != reflect.TypeOf(&types.Actor{}) { return nil, newErr("first arguemnt should be *types.Actor") } if t.In(1) != tVMContext { return nil, newErr("second argument should be types.VMContext") } if t.In(2).Kind() != reflect.Ptr { return nil, newErr("parameter has to be a pointer to parameter, is: %s", t.In(2).Kind()) } if t.NumOut() != 2 { return nil, newErr("wrong number of outputs should be: " + "(InvokeRet, error)") } if t.Out(0) != reflect.TypeOf([]byte{}) { return nil, newErr("first output should be slice of bytes") } if !t.Out(1).Implements(tAError) { return nil, newErr("second output should be ActorError type") } } code := make(nativeCode, len(exports)) for id, m := range exports { meth := reflect.ValueOf(m) code[id] = reflect.MakeFunc(reflect.TypeOf((invokeFunc)(nil)), func(in []reflect.Value) []reflect.Value { paramT := meth.Type().In(2).Elem() param := reflect.New(paramT) inBytes := in[2].Interface().([]byte) if len(inBytes) > 0 { if err := DecodeParams(inBytes, param.Interface()); err != nil { aerr := aerrors.Absorb(err, 1, "failed to decode parameters") return []reflect.Value{ reflect.ValueOf([]byte{}), // Below is a hack, fixed in Go 1.13 // https://git.io/fjXU6 reflect.ValueOf(&aerr).Elem(), } } } return meth.Call([]reflect.Value{ in[0], in[1], param, }) }).Interface().(invokeFunc) } return code, nil } func DecodeParams(b []byte, out interface{}) error { um, ok := out.(cbg.CBORUnmarshaler) if !ok { return fmt.Errorf("type %T does not implement UnmarshalCBOR", out) } return um.UnmarshalCBOR(bytes.NewReader(b)) } func DumpActorState(code cid.Cid, b []byte) (interface{}, error) { i := newInvoker() // TODO: register builtins in init block typ, ok := i.builtInState[code] if !ok { return nil, xerrors.Errorf("state type for actor %s not found", code) } rv := reflect.New(typ) um, ok := rv.Interface().(cbg.CBORUnmarshaler) if !ok { return nil, xerrors.New("state type does not implement CBORUnmarshaler") } if err := um.UnmarshalCBOR(bytes.NewReader(b)); err != nil { return nil, err } return rv.Elem().Interface(), nil }