lotus/chain/vm/invoker.go
2020-02-08 03:18:32 +01:00

281 lines
8.0 KiB
Go

package vm
import (
"bytes"
"encoding/hex"
"fmt"
"reflect"
"strings"
"github.com/ipfs/go-cid"
cbg "github.com/whyrusleeping/cbor-gen"
"golang.org/x/xerrors"
"github.com/filecoin-project/specs-actors/actors/builtin/multisig"
vmr "github.com/filecoin-project/specs-actors/actors/runtime"
"github.com/filecoin-project/specs-actors/actors/builtin/market"
"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, market.Actor{}, market.State{})
inv.Register(actors.StorageMinerCodeCid, actors.StorageMinerActor{}, actors.StorageMinerActorState{})
inv.Register(actors.MultisigCodeCid, multisig.Actor{}, multisig.State{})
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 (i *invoker) transform(instance Invokee) (nativeCode, error) {
itype := reflect.TypeOf(instance)
if strings.Contains(itype.PkgPath(), "github.com/filecoin-project/specs-actors/") {
return i.transformSpec(instance)
} else {
return i.transformLotus(instance)
}
}
func (*invoker) transformSpec(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() != 2 {
return nil, newErr("wrong number of inputs should be: " +
"vmr.Runtime, <parameter>")
}
if t.In(0) != reflect.TypeOf((*vmr.Runtime)(nil)).Elem() {
return nil, newErr("first arguemnt should be vmr.Runtime")
}
if t.In(1).Kind() != reflect.Ptr {
return nil, newErr("second argument should be types.VMContext")
}
if t.NumOut() != 1 {
return nil, newErr("wrong number of outputs should be: " +
"cbg.CBORMarshaler")
}
o0 := t.Out(0)
if !o0.Implements(reflect.TypeOf((*cbg.CBORMarshaler)(nil)).Elem()) {
return nil, newErr("output needs to implement cgb.CBORMarshaler")
}
}
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(1).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(),
}
}
}
shim := &runtimeShim{vmctx: in[1].Interface().(*VMContext)}
rval, aerror := shim.shimCall(func() interface{} {
ret := meth.Call([]reflect.Value{
reflect.ValueOf(shim),
param,
})
return ret[0].Interface()
})
return []reflect.Value{
reflect.ValueOf(&rval).Elem(),
reflect.ValueOf(&aerror).Elem(),
}
}).Interface().(invokeFunc)
}
return code, nil
}
func (*invoker) transformLotus(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, <type of parameter>")
}
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) {
if code == actors.AccountCodeCid { // Account code special case
return nil, nil
}
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
}