package dao import ( "bytes" "encoding/binary" "fmt" "sort" "github.com/nspcc-dev/neo-go/pkg/core/block" "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/core/transaction" "github.com/nspcc-dev/neo-go/pkg/io" "github.com/nspcc-dev/neo-go/pkg/util" ) // DAO is a data access object. type DAO interface { AppendNEP5Transfer(acc util.Uint160, index uint32, tr *state.NEP5Transfer) (bool, error) DeleteContractState(hash util.Uint160) error DeleteStorageItem(scripthash util.Uint160, key []byte) error GetAccountState(hash util.Uint160) (*state.Account, error) GetAccountStateOrNew(hash util.Uint160) (*state.Account, error) GetAndDecode(entity io.Serializable, key []byte) error GetAppExecResult(hash util.Uint256) (*state.AppExecResult, error) GetAssetState(assetID util.Uint256) (*state.Asset, error) GetBatch() *storage.MemBatch GetBlock(hash util.Uint256) (*block.Block, error) GetContractState(hash util.Uint160) (*state.Contract, error) GetCurrentBlockHeight() (uint32, error) GetCurrentHeaderHeight() (i uint32, h util.Uint256, err error) GetHeaderHashes() ([]util.Uint256, error) GetNEP5Balances(acc util.Uint160) (*state.NEP5Balances, error) GetNEP5TransferLog(acc util.Uint160, index uint32) (*state.NEP5TransferLog, error) GetStorageItem(scripthash util.Uint160, key []byte) *state.StorageItem GetStorageItems(hash util.Uint160) (map[string]*state.StorageItem, error) GetStorageItemsWithPrefix(hash util.Uint160, prefix []byte) (map[string]*state.StorageItem, error) GetTransaction(hash util.Uint256) (*transaction.Transaction, uint32, error) GetUnspentCoinState(hash util.Uint256) (*state.UnspentCoin, error) GetVersion() (string, error) GetWrapped() DAO HasTransaction(hash util.Uint256) bool IsDoubleSpend(tx *transaction.Transaction) bool Persist() (int, error) PutAccountState(as *state.Account) error PutAppExecResult(aer *state.AppExecResult) error PutAssetState(as *state.Asset) error PutContractState(cs *state.Contract) error PutCurrentHeader(hashAndIndex []byte) error PutNEP5Balances(acc util.Uint160, bs *state.NEP5Balances) error PutNEP5TransferLog(acc util.Uint160, index uint32, lg *state.NEP5TransferLog) error PutStorageItem(scripthash util.Uint160, key []byte, si *state.StorageItem) error PutUnspentCoinState(hash util.Uint256, ucs *state.UnspentCoin) error PutVersion(v string) error StoreAsBlock(block *block.Block) error StoreAsCurrentBlock(block *block.Block) error StoreAsTransaction(tx *transaction.Transaction, index uint32) error putAccountState(as *state.Account, buf *io.BufBinWriter) error putNEP5Balances(acc util.Uint160, bs *state.NEP5Balances, buf *io.BufBinWriter) error putUnspentCoinState(hash util.Uint256, ucs *state.UnspentCoin, buf *io.BufBinWriter) error } // Simple is memCached wrapper around DB, simple DAO implementation. type Simple struct { Store *storage.MemCachedStore } // NewSimple creates new simple dao using provided backend store. func NewSimple(backend storage.Store) *Simple { return &Simple{Store: storage.NewMemCachedStore(backend)} } // GetBatch returns currently accumulated DB changeset. func (dao *Simple) GetBatch() *storage.MemBatch { return dao.Store.GetBatch() } // GetWrapped returns new DAO instance with another layer of wrapped // MemCachedStore around the current DAO Store. func (dao *Simple) GetWrapped() DAO { return NewSimple(dao.Store) } // GetAndDecode performs get operation and decoding with serializable structures. func (dao *Simple) GetAndDecode(entity io.Serializable, key []byte) error { entityBytes, err := dao.Store.Get(key) if err != nil { return err } reader := io.NewBinReaderFromBuf(entityBytes) entity.DecodeBinary(reader) return reader.Err } // Put performs put operation with serializable structures. func (dao *Simple) Put(entity io.Serializable, key []byte) error { return dao.putWithBuffer(entity, key, io.NewBufBinWriter()) } // putWithBuffer performs put operation using buf as a pre-allocated buffer for serialization. func (dao *Simple) putWithBuffer(entity io.Serializable, key []byte, buf *io.BufBinWriter) error { entity.EncodeBinary(buf.BinWriter) if buf.Err != nil { return buf.Err } return dao.Store.Put(key, buf.Bytes()) } // -- start accounts. // GetAccountStateOrNew retrieves Account from temporary or persistent Store // or creates a new one if it doesn't exist and persists it. func (dao *Simple) GetAccountStateOrNew(hash util.Uint160) (*state.Account, error) { account, err := dao.GetAccountState(hash) if err != nil { if err != storage.ErrKeyNotFound { return nil, err } account = state.NewAccount(hash) } return account, nil } // GetAccountState returns Account from the given Store if it's // present there. Returns nil otherwise. func (dao *Simple) GetAccountState(hash util.Uint160) (*state.Account, error) { account := &state.Account{} key := storage.AppendPrefix(storage.STAccount, hash.BytesBE()) err := dao.GetAndDecode(account, key) if err != nil { return nil, err } return account, err } // PutAccountState saves given Account in given store. func (dao *Simple) PutAccountState(as *state.Account) error { return dao.putAccountState(as, io.NewBufBinWriter()) } func (dao *Simple) putAccountState(as *state.Account, buf *io.BufBinWriter) error { key := storage.AppendPrefix(storage.STAccount, as.ScriptHash.BytesBE()) return dao.putWithBuffer(as, key, buf) } // -- end accounts. // -- start assets. // GetAssetState returns given asset state as recorded in the given store. func (dao *Simple) GetAssetState(assetID util.Uint256) (*state.Asset, error) { asset := &state.Asset{} key := storage.AppendPrefix(storage.STAsset, assetID.BytesBE()) err := dao.GetAndDecode(asset, key) if err != nil { return nil, err } if asset.ID != assetID { return nil, fmt.Errorf("found asset id is not equal to expected") } return asset, nil } // PutAssetState puts given asset state into the given store. func (dao *Simple) PutAssetState(as *state.Asset) error { key := storage.AppendPrefix(storage.STAsset, as.ID.BytesBE()) return dao.Put(as, key) } // -- end assets. // -- start contracts. // GetContractState returns contract state as recorded in the given // store by the given script hash. func (dao *Simple) GetContractState(hash util.Uint160) (*state.Contract, error) { contract := &state.Contract{} key := storage.AppendPrefix(storage.STContract, hash.BytesBE()) err := dao.GetAndDecode(contract, key) if err != nil { return nil, err } if contract.ScriptHash() != hash { return nil, fmt.Errorf("found script hash is not equal to expected") } return contract, nil } // PutContractState puts given contract state into the given store. func (dao *Simple) PutContractState(cs *state.Contract) error { key := storage.AppendPrefix(storage.STContract, cs.ScriptHash().BytesBE()) return dao.Put(cs, key) } // DeleteContractState deletes given contract state in the given store. func (dao *Simple) DeleteContractState(hash util.Uint160) error { key := storage.AppendPrefix(storage.STContract, hash.BytesBE()) return dao.Store.Delete(key) } // -- end contracts. // -- start nep5 balances. // GetNEP5Balances retrieves nep5 balances from the cache. func (dao *Simple) GetNEP5Balances(acc util.Uint160) (*state.NEP5Balances, error) { key := storage.AppendPrefix(storage.STNEP5Balances, acc.BytesBE()) bs := state.NewNEP5Balances() err := dao.GetAndDecode(bs, key) if err != nil && err != storage.ErrKeyNotFound { return nil, err } return bs, nil } // PutNEP5Balances saves nep5 balances from the cache. func (dao *Simple) PutNEP5Balances(acc util.Uint160, bs *state.NEP5Balances) error { return dao.putNEP5Balances(acc, bs, io.NewBufBinWriter()) } func (dao *Simple) putNEP5Balances(acc util.Uint160, bs *state.NEP5Balances, buf *io.BufBinWriter) error { key := storage.AppendPrefix(storage.STNEP5Balances, acc.BytesBE()) return dao.putWithBuffer(bs, key, buf) } // -- end nep5 balances. // -- start transfer log. const nep5TransferBatchSize = 128 func getNEP5TransferLogKey(acc util.Uint160, index uint32) []byte { key := make([]byte, 1+util.Uint160Size+4) key[0] = byte(storage.STNEP5Transfers) copy(key[1:], acc.BytesBE()) binary.LittleEndian.PutUint32(key[util.Uint160Size:], index) return key } // GetNEP5TransferLog retrieves transfer log from the cache. func (dao *Simple) GetNEP5TransferLog(acc util.Uint160, index uint32) (*state.NEP5TransferLog, error) { key := getNEP5TransferLogKey(acc, index) value, err := dao.Store.Get(key) if err != nil { if err == storage.ErrKeyNotFound { return new(state.NEP5TransferLog), nil } return nil, err } return &state.NEP5TransferLog{Raw: value}, nil } // PutNEP5TransferLog saves given transfer log in the cache. func (dao *Simple) PutNEP5TransferLog(acc util.Uint160, index uint32, lg *state.NEP5TransferLog) error { key := getNEP5TransferLogKey(acc, index) return dao.Store.Put(key, lg.Raw) } // AppendNEP5Transfer appends a single NEP5 transfer to a log. // First return value signalizes that log size has exceeded batch size. func (dao *Simple) AppendNEP5Transfer(acc util.Uint160, index uint32, tr *state.NEP5Transfer) (bool, error) { lg, err := dao.GetNEP5TransferLog(acc, index) if err != nil { if err != storage.ErrKeyNotFound { return false, err } lg = new(state.NEP5TransferLog) } if err := lg.Append(tr); err != nil { return false, err } return lg.Size() >= nep5TransferBatchSize, dao.PutNEP5TransferLog(acc, index, lg) } // -- end transfer log. // -- start unspent coins. // GetUnspentCoinState retrieves UnspentCoinState from the given store. func (dao *Simple) GetUnspentCoinState(hash util.Uint256) (*state.UnspentCoin, error) { unspent := &state.UnspentCoin{} key := storage.AppendPrefix(storage.STCoin, hash.BytesLE()) err := dao.GetAndDecode(unspent, key) if err != nil { return nil, err } return unspent, nil } // PutUnspentCoinState puts given UnspentCoinState into the given store. func (dao *Simple) PutUnspentCoinState(hash util.Uint256, ucs *state.UnspentCoin) error { return dao.putUnspentCoinState(hash, ucs, io.NewBufBinWriter()) } func (dao *Simple) putUnspentCoinState(hash util.Uint256, ucs *state.UnspentCoin, buf *io.BufBinWriter) error { key := storage.AppendPrefix(storage.STCoin, hash.BytesLE()) return dao.putWithBuffer(ucs, key, buf) } // -- end unspent coins. // -- start notification event. // GetAppExecResult gets application execution result from the // given store. func (dao *Simple) GetAppExecResult(hash util.Uint256) (*state.AppExecResult, error) { aer := &state.AppExecResult{} key := storage.AppendPrefix(storage.STNotification, hash.BytesBE()) err := dao.GetAndDecode(aer, key) if err != nil { return nil, err } return aer, nil } // PutAppExecResult puts given application execution result into the // given store. func (dao *Simple) PutAppExecResult(aer *state.AppExecResult) error { key := storage.AppendPrefix(storage.STNotification, aer.TxHash.BytesBE()) return dao.Put(aer, key) } // -- end notification event. // -- start storage item. // GetStorageItem returns StorageItem if it exists in the given store. func (dao *Simple) GetStorageItem(scripthash util.Uint160, key []byte) *state.StorageItem { b, err := dao.Store.Get(makeStorageItemKey(scripthash, key)) if err != nil { return nil } r := io.NewBinReaderFromBuf(b) si := &state.StorageItem{} si.DecodeBinary(r) if r.Err != nil { return nil } return si } // PutStorageItem puts given StorageItem for given script with given // key into the given store. func (dao *Simple) PutStorageItem(scripthash util.Uint160, key []byte, si *state.StorageItem) error { return dao.Put(si, makeStorageItemKey(scripthash, key)) } // DeleteStorageItem drops storage item for the given script with the // given key from the store. func (dao *Simple) DeleteStorageItem(scripthash util.Uint160, key []byte) error { return dao.Store.Delete(makeStorageItemKey(scripthash, key)) } // GetStorageItems returns all storage items for a given scripthash. func (dao *Simple) GetStorageItems(hash util.Uint160) (map[string]*state.StorageItem, error) { return dao.GetStorageItemsWithPrefix(hash, nil) } // GetStorageItemsWithPrefix returns all storage items with given prefix for a // given scripthash. func (dao *Simple) GetStorageItemsWithPrefix(hash util.Uint160, prefix []byte) (map[string]*state.StorageItem, error) { var siMap = make(map[string]*state.StorageItem) var err error lookupKey := storage.AppendPrefix(storage.STStorage, hash.BytesLE()) if prefix != nil { lookupKey = append(lookupKey, prefix...) } saveToMap := func(k, v []byte) { if err != nil { return } r := io.NewBinReaderFromBuf(v) si := &state.StorageItem{} si.DecodeBinary(r) if r.Err != nil { err = r.Err return } // Cut prefix and hash. siMap[string(k[len(lookupKey):])] = si } dao.Store.Seek(lookupKey, saveToMap) if err != nil { return nil, err } return siMap, nil } // makeStorageItemKey returns a key used to store StorageItem in the DB. func makeStorageItemKey(scripthash util.Uint160, key []byte) []byte { return storage.AppendPrefix(storage.STStorage, append(scripthash.BytesLE(), key...)) } // -- end storage item. // -- other. // GetBlock returns Block by the given hash if it exists in the store. func (dao *Simple) GetBlock(hash util.Uint256) (*block.Block, error) { key := storage.AppendPrefix(storage.DataBlock, hash.BytesLE()) b, err := dao.Store.Get(key) if err != nil { return nil, err } block, err := block.NewBlockFromTrimmedBytes(b) if err != nil { return nil, err } return block, nil } // GetVersion attempts to get the current version stored in the // underlying store. func (dao *Simple) GetVersion() (string, error) { version, err := dao.Store.Get(storage.SYSVersion.Bytes()) return string(version), err } // GetCurrentBlockHeight returns the current block height found in the // underlying store. func (dao *Simple) GetCurrentBlockHeight() (uint32, error) { b, err := dao.Store.Get(storage.SYSCurrentBlock.Bytes()) if err != nil { return 0, err } return binary.LittleEndian.Uint32(b[32:36]), nil } // GetCurrentHeaderHeight returns the current header height and hash from // the underlying store. func (dao *Simple) GetCurrentHeaderHeight() (i uint32, h util.Uint256, err error) { var b []byte b, err = dao.Store.Get(storage.SYSCurrentHeader.Bytes()) if err != nil { return } i = binary.LittleEndian.Uint32(b[32:36]) h, err = util.Uint256DecodeBytesLE(b[:32]) return } // GetHeaderHashes returns a sorted list of header hashes retrieved from // the given underlying store. func (dao *Simple) GetHeaderHashes() ([]util.Uint256, error) { hashMap := make(map[uint32][]util.Uint256) dao.Store.Seek(storage.IXHeaderHashList.Bytes(), func(k, v []byte) { storedCount := binary.LittleEndian.Uint32(k[1:]) hashes, err := read2000Uint256Hashes(v) if err != nil { panic(err) } hashMap[storedCount] = hashes }) var ( hashes = make([]util.Uint256, 0, len(hashMap)) sortedKeys = make([]uint32, 0, len(hashMap)) ) for k := range hashMap { sortedKeys = append(sortedKeys, k) } sort.Slice(sortedKeys, func(i, j int) bool { return sortedKeys[i] < sortedKeys[j] }) for _, key := range sortedKeys { hashes = append(hashes[:key], hashMap[key]...) } return hashes, nil } // GetTransaction returns Transaction and its height by the given hash // if it exists in the store. func (dao *Simple) GetTransaction(hash util.Uint256) (*transaction.Transaction, uint32, error) { key := storage.AppendPrefix(storage.DataTransaction, hash.BytesLE()) b, err := dao.Store.Get(key) if err != nil { return nil, 0, err } r := io.NewBinReaderFromBuf(b) var height = r.ReadU32LE() tx := &transaction.Transaction{} tx.DecodeBinary(r) if r.Err != nil { return nil, 0, r.Err } return tx, height, nil } // PutVersion stores the given version in the underlying store. func (dao *Simple) PutVersion(v string) error { return dao.Store.Put(storage.SYSVersion.Bytes(), []byte(v)) } // PutCurrentHeader stores current header. func (dao *Simple) PutCurrentHeader(hashAndIndex []byte) error { return dao.Store.Put(storage.SYSCurrentHeader.Bytes(), hashAndIndex) } // read2000Uint256Hashes attempts to read 2000 Uint256 hashes from // the given byte array. func read2000Uint256Hashes(b []byte) ([]util.Uint256, error) { r := bytes.NewReader(b) br := io.NewBinReaderFromIO(r) hashes := make([]util.Uint256, 0) br.ReadArray(&hashes) if br.Err != nil { return nil, br.Err } return hashes, nil } // HasTransaction returns true if the given store contains the given // Transaction hash. func (dao *Simple) HasTransaction(hash util.Uint256) bool { key := storage.AppendPrefix(storage.DataTransaction, hash.BytesLE()) if _, err := dao.Store.Get(key); err == nil { return true } return false } // StoreAsBlock stores the given block as DataBlock. func (dao *Simple) StoreAsBlock(block *block.Block) error { var ( key = storage.AppendPrefix(storage.DataBlock, block.Hash().BytesLE()) buf = io.NewBufBinWriter() ) b, err := block.Trim() if err != nil { return err } buf.WriteBytes(b) if buf.Err != nil { return buf.Err } return dao.Store.Put(key, buf.Bytes()) } // StoreAsCurrentBlock stores the given block witch prefix SYSCurrentBlock. func (dao *Simple) StoreAsCurrentBlock(block *block.Block) error { buf := io.NewBufBinWriter() h := block.Hash() h.EncodeBinary(buf.BinWriter) buf.WriteU32LE(block.Index) return dao.Store.Put(storage.SYSCurrentBlock.Bytes(), buf.Bytes()) } // StoreAsTransaction stores the given TX as DataTransaction. func (dao *Simple) StoreAsTransaction(tx *transaction.Transaction, index uint32) error { key := storage.AppendPrefix(storage.DataTransaction, tx.Hash().BytesLE()) buf := io.NewBufBinWriter() buf.WriteU32LE(index) tx.EncodeBinary(buf.BinWriter) if buf.Err != nil { return buf.Err } return dao.Store.Put(key, buf.Bytes()) } // IsDoubleSpend verifies that the input transactions are not double spent. func (dao *Simple) IsDoubleSpend(tx *transaction.Transaction) bool { return dao.checkUsedInputs(tx.Inputs, state.CoinSpent) } func (dao *Simple) checkUsedInputs(inputs []transaction.Input, coin state.Coin) bool { if len(inputs) == 0 { return false } for _, inputs := range transaction.GroupInputsByPrevHash(inputs) { prevHash := inputs[0].PrevHash unspent, err := dao.GetUnspentCoinState(prevHash) if err != nil { return true } for _, input := range inputs { if int(input.PrevIndex) >= len(unspent.States) || (unspent.States[input.PrevIndex].State&coin) != 0 { return true } } } return false } // Persist flushes all the changes made into the (supposedly) persistent // underlying store. func (dao *Simple) Persist() (int, error) { return dao.Store.Persist() }