package stateroot import ( "encoding/binary" "errors" "fmt" "github.com/nspcc-dev/neo-go/pkg/core/state" "github.com/nspcc-dev/neo-go/pkg/core/storage" "github.com/nspcc-dev/neo-go/pkg/io" ) var ( // ErrStateMismatch means that local state root doesn't match the one // signed by state validators. ErrStateMismatch = errors.New("stateroot mismatch") ) const ( prefixLocal = 0x02 prefixValidated = 0x03 ) func (s *Module) addLocalStateRoot(store *storage.MemCachedStore, sr *state.MPTRoot) error { key := makeStateRootKey(sr.Index) if err := putStateRoot(store, key, sr); err != nil { return err } data := make([]byte, 4) binary.LittleEndian.PutUint32(data, sr.Index) return store.Put([]byte{byte(storage.DataMPT), prefixLocal}, data) } func putStateRoot(store *storage.MemCachedStore, key []byte, sr *state.MPTRoot) error { w := io.NewBufBinWriter() sr.EncodeBinary(w.BinWriter) return store.Put(key, w.Bytes()) } func (s *Module) getStateRoot(key []byte) (*state.MPTRoot, error) { data, err := s.Store.Get(key) if err != nil { return nil, err } sr := &state.MPTRoot{} r := io.NewBinReaderFromBuf(data) sr.DecodeBinary(r) return sr, r.Err } func makeStateRootKey(index uint32) []byte { key := make([]byte, 5) key[0] = byte(storage.DataMPT) binary.BigEndian.PutUint32(key, index) return key } // AddStateRoot adds validated state root provided by network. func (s *Module) AddStateRoot(sr *state.MPTRoot) error { if err := s.VerifyStateRoot(sr); err != nil { return err } key := makeStateRootKey(sr.Index) local, err := s.getStateRoot(key) if err != nil { return err } if !local.Root.Equals(sr.Root) { return fmt.Errorf("%w at block %d: %v vs %v", ErrStateMismatch, sr.Index, local.Root, sr.Root) } if len(local.Witness) != 0 { return nil } if err := putStateRoot(s.Store, key, sr); err != nil { return err } data := make([]byte, 4) binary.LittleEndian.PutUint32(data, sr.Index) if err := s.Store.Put([]byte{byte(storage.DataMPT), prefixValidated}, data); err != nil { return err } s.validatedHeight.Store(sr.Index) if !s.srInHead { updateStateHeightMetric(sr.Index) } return nil }