package server import ( "context" "encoding/hex" "encoding/json" "fmt" "math" "net" "net/http" "strconv" "sync" "time" "github.com/gorilla/websocket" "github.com/nspcc-dev/neo-go/pkg/config/netmode" "github.com/nspcc-dev/neo-go/pkg/core" "github.com/nspcc-dev/neo-go/pkg/core/block" "github.com/nspcc-dev/neo-go/pkg/core/blockchainer" "github.com/nspcc-dev/neo-go/pkg/core/state" "github.com/nspcc-dev/neo-go/pkg/core/transaction" "github.com/nspcc-dev/neo-go/pkg/crypto/keys" "github.com/nspcc-dev/neo-go/pkg/encoding/address" "github.com/nspcc-dev/neo-go/pkg/encoding/bigint" "github.com/nspcc-dev/neo-go/pkg/io" "github.com/nspcc-dev/neo-go/pkg/network" "github.com/nspcc-dev/neo-go/pkg/rpc" "github.com/nspcc-dev/neo-go/pkg/rpc/request" "github.com/nspcc-dev/neo-go/pkg/rpc/response" "github.com/nspcc-dev/neo-go/pkg/rpc/response/result" "github.com/nspcc-dev/neo-go/pkg/smartcontract" "github.com/nspcc-dev/neo-go/pkg/util" "github.com/pkg/errors" "go.uber.org/zap" ) type ( // Server represents the JSON-RPC 2.0 server. Server struct { *http.Server chain blockchainer.Blockchainer config rpc.Config network netmode.Magic coreServer *network.Server log *zap.Logger https *http.Server shutdown chan struct{} subsLock sync.RWMutex subscribers map[*subscriber]bool subsGroup sync.WaitGroup blockSubs int executionSubs int notificationSubs int transactionSubs int blockCh chan *block.Block executionCh chan *state.AppExecResult notificationCh chan *state.NotificationEvent transactionCh chan *transaction.Transaction } ) const ( // Message limit for receiving side. wsReadLimit = 4096 // Disconnection timeout. wsPongLimit = 60 * time.Second // Ping period for connection liveness check. wsPingPeriod = wsPongLimit / 2 // Write deadline. wsWriteLimit = wsPingPeriod / 2 // Maximum number of subscribers per Server. Each websocket client is // treated like subscriber, so technically it's a limit on websocket // connections. maxSubscribers = 64 ) var rpcHandlers = map[string]func(*Server, request.Params) (interface{}, *response.Error){ "getapplicationlog": (*Server).getApplicationLog, "getbestblockhash": (*Server).getBestBlockHash, "getblock": (*Server).getBlock, "getblockcount": (*Server).getBlockCount, "getblockhash": (*Server).getBlockHash, "getblockheader": (*Server).getBlockHeader, "getblocksysfee": (*Server).getBlockSysFee, "getconnectioncount": (*Server).getConnectionCount, "getcontractstate": (*Server).getContractState, "getnep5balances": (*Server).getNEP5Balances, "getnep5transfers": (*Server).getNEP5Transfers, "getpeers": (*Server).getPeers, "getrawmempool": (*Server).getRawMempool, "getrawtransaction": (*Server).getrawtransaction, "getstorage": (*Server).getStorage, "gettransactionheight": (*Server).getTransactionHeight, "getunclaimedgas": (*Server).getUnclaimedGas, "getvalidators": (*Server).getValidators, "getversion": (*Server).getVersion, "invokefunction": (*Server).invokeFunction, "invokescript": (*Server).invokescript, "sendrawtransaction": (*Server).sendrawtransaction, "submitblock": (*Server).submitBlock, "validateaddress": (*Server).validateAddress, } var rpcWsHandlers = map[string]func(*Server, request.Params, *subscriber) (interface{}, *response.Error){ "subscribe": (*Server).subscribe, "unsubscribe": (*Server).unsubscribe, } var invalidBlockHeightError = func(index int, height int) *response.Error { return response.NewRPCError(fmt.Sprintf("Param at index %d should be greater than or equal to 0 and less then or equal to current block height, got: %d", index, height), "", nil) } // upgrader is a no-op websocket.Upgrader that reuses HTTP server buffers and // doesn't set any Error function. var upgrader = websocket.Upgrader{} // New creates a new Server struct. func New(chain blockchainer.Blockchainer, conf rpc.Config, coreServer *network.Server, log *zap.Logger) Server { httpServer := &http.Server{ Addr: conf.Address + ":" + strconv.FormatUint(uint64(conf.Port), 10), } var tlsServer *http.Server if cfg := conf.TLSConfig; cfg.Enabled { tlsServer = &http.Server{ Addr: net.JoinHostPort(cfg.Address, strconv.FormatUint(uint64(cfg.Port), 10)), } } return Server{ Server: httpServer, chain: chain, config: conf, network: chain.GetConfig().Magic, coreServer: coreServer, log: log, https: tlsServer, shutdown: make(chan struct{}), subscribers: make(map[*subscriber]bool), // These are NOT buffered to preserve original order of events. blockCh: make(chan *block.Block), executionCh: make(chan *state.AppExecResult), notificationCh: make(chan *state.NotificationEvent), transactionCh: make(chan *transaction.Transaction), } } // Start creates a new JSON-RPC server listening on the configured port. It's // supposed to be run as a separate goroutine (like http.Server's Serve) and it // returns its errors via given errChan. func (s *Server) Start(errChan chan error) { if !s.config.Enabled { s.log.Info("RPC server is not enabled") return } s.Handler = http.HandlerFunc(s.handleHTTPRequest) s.log.Info("starting rpc-server", zap.String("endpoint", s.Addr)) go s.handleSubEvents() if cfg := s.config.TLSConfig; cfg.Enabled { s.https.Handler = http.HandlerFunc(s.handleHTTPRequest) s.log.Info("starting rpc-server (https)", zap.String("endpoint", s.https.Addr)) go func() { err := s.https.ListenAndServeTLS(cfg.CertFile, cfg.KeyFile) if err != http.ErrServerClosed { s.log.Error("failed to start TLS RPC server", zap.Error(err)) errChan <- err } }() } err := s.ListenAndServe() if err != http.ErrServerClosed { s.log.Error("failed to start RPC server", zap.Error(err)) errChan <- err } } // Shutdown overrides the http.Server Shutdown // method. func (s *Server) Shutdown() error { var httpsErr error // Signal to websocket writer routines and handleSubEvents. close(s.shutdown) if s.config.TLSConfig.Enabled { s.log.Info("shutting down rpc-server (https)", zap.String("endpoint", s.https.Addr)) httpsErr = s.https.Shutdown(context.Background()) } s.log.Info("shutting down rpc-server", zap.String("endpoint", s.Addr)) err := s.Server.Shutdown(context.Background()) // Wait for handleSubEvents to finish. <-s.executionCh if err == nil { return httpsErr } return err } func (s *Server) handleHTTPRequest(w http.ResponseWriter, httpRequest *http.Request) { req := request.NewIn() if httpRequest.URL.Path == "/ws" && httpRequest.Method == "GET" { // Technically there is a race between this check and // s.subscribers modification 20 lines below, but it's tiny // and not really critical to bother with it. Some additional // clients may sneak in, no big deal. s.subsLock.RLock() numOfSubs := len(s.subscribers) s.subsLock.RUnlock() if numOfSubs >= maxSubscribers { s.writeHTTPErrorResponse( req, w, response.NewInternalServerError("websocket users limit reached", nil), ) return } ws, err := upgrader.Upgrade(w, httpRequest, nil) if err != nil { s.log.Info("websocket connection upgrade failed", zap.Error(err)) return } resChan := make(chan response.Raw) subChan := make(chan *websocket.PreparedMessage, notificationBufSize) subscr := &subscriber{writer: subChan, ws: ws} s.subsLock.Lock() s.subscribers[subscr] = true s.subsLock.Unlock() go s.handleWsWrites(ws, resChan, subChan) s.handleWsReads(ws, resChan, subscr) return } if httpRequest.Method != "POST" { s.writeHTTPErrorResponse( req, w, response.NewInvalidParamsError( fmt.Sprintf("Invalid method '%s', please retry with 'POST'", httpRequest.Method), nil, ), ) return } err := req.DecodeData(httpRequest.Body) if err != nil { s.writeHTTPErrorResponse(req, w, response.NewParseError("Problem parsing JSON-RPC request body", err)) return } resp := s.handleRequest(req, nil) s.writeHTTPServerResponse(req, w, resp) } func (s *Server) handleRequest(req *request.In, sub *subscriber) response.Raw { var res interface{} var resErr *response.Error reqParams, err := req.Params() if err != nil { return s.packResponseToRaw(req, nil, response.NewInvalidParamsError("Problem parsing request parameters", err)) } s.log.Debug("processing rpc request", zap.String("method", req.Method), zap.String("params", fmt.Sprintf("%v", reqParams))) incCounter(req.Method) resErr = response.NewMethodNotFoundError(fmt.Sprintf("Method '%s' not supported", req.Method), nil) handler, ok := rpcHandlers[req.Method] if ok { res, resErr = handler(s, *reqParams) } else if sub != nil { handler, ok := rpcWsHandlers[req.Method] if ok { res, resErr = handler(s, *reqParams, sub) } } return s.packResponseToRaw(req, res, resErr) } func (s *Server) handleWsWrites(ws *websocket.Conn, resChan <-chan response.Raw, subChan <-chan *websocket.PreparedMessage) { pingTicker := time.NewTicker(wsPingPeriod) eventloop: for { select { case <-s.shutdown: break eventloop case event, ok := <-subChan: if !ok { break eventloop } ws.SetWriteDeadline(time.Now().Add(wsWriteLimit)) if err := ws.WritePreparedMessage(event); err != nil { break eventloop } case res, ok := <-resChan: if !ok { break eventloop } ws.SetWriteDeadline(time.Now().Add(wsWriteLimit)) if err := ws.WriteJSON(res); err != nil { break eventloop } case <-pingTicker.C: ws.SetWriteDeadline(time.Now().Add(wsWriteLimit)) if err := ws.WriteMessage(websocket.PingMessage, []byte{}); err != nil { break eventloop } } } ws.Close() pingTicker.Stop() // Drain notification channel as there might be some goroutines blocked // on it. drainloop: for { select { case _, ok := <-subChan: if !ok { break drainloop } default: break drainloop } } } func (s *Server) handleWsReads(ws *websocket.Conn, resChan chan<- response.Raw, subscr *subscriber) { ws.SetReadLimit(wsReadLimit) ws.SetReadDeadline(time.Now().Add(wsPongLimit)) ws.SetPongHandler(func(string) error { ws.SetReadDeadline(time.Now().Add(wsPongLimit)); return nil }) requestloop: for { req := new(request.In) err := ws.ReadJSON(req) if err != nil { break } res := s.handleRequest(req, subscr) if res.Error != nil { s.logRequestError(req, res.Error) } select { case <-s.shutdown: break requestloop case resChan <- res: } } s.subsLock.Lock() delete(s.subscribers, subscr) for _, e := range subscr.feeds { if e.event != response.InvalidEventID { s.unsubscribeFromChannel(e.event) } } s.subsLock.Unlock() close(resChan) ws.Close() } func (s *Server) getBestBlockHash(_ request.Params) (interface{}, *response.Error) { return "0x" + s.chain.CurrentBlockHash().StringLE(), nil } func (s *Server) getBlockCount(_ request.Params) (interface{}, *response.Error) { return s.chain.BlockHeight() + 1, nil } func (s *Server) getConnectionCount(_ request.Params) (interface{}, *response.Error) { return s.coreServer.PeerCount(), nil } func (s *Server) blockHashFromParam(param *request.Param) (util.Uint256, *response.Error) { var hash util.Uint256 switch param.Type { case request.StringT: var err error hash, err = param.GetUint256() if err != nil { return hash, response.ErrInvalidParams } case request.NumberT: num, err := s.blockHeightFromParam(param) if err != nil { return hash, response.ErrInvalidParams } hash = s.chain.GetHeaderHash(num) default: return hash, response.ErrInvalidParams } return hash, nil } func (s *Server) getBlock(reqParams request.Params) (interface{}, *response.Error) { param, ok := reqParams.Value(0) if !ok { return nil, response.ErrInvalidParams } hash, respErr := s.blockHashFromParam(param) if respErr != nil { return nil, respErr } block, err := s.chain.GetBlock(hash) if err != nil { return nil, response.NewInternalServerError(fmt.Sprintf("Problem locating block with hash: %s", hash), err) } if len(reqParams) == 2 && reqParams[1].Value == 1 { return result.NewBlock(block, s.chain), nil } writer := io.NewBufBinWriter() block.EncodeBinary(writer.BinWriter) return hex.EncodeToString(writer.Bytes()), nil } func (s *Server) getBlockHash(reqParams request.Params) (interface{}, *response.Error) { param, ok := reqParams.ValueWithType(0, request.NumberT) if !ok { return nil, response.ErrInvalidParams } num, err := s.blockHeightFromParam(param) if err != nil { return nil, response.ErrInvalidParams } return s.chain.GetHeaderHash(num), nil } func (s *Server) getVersion(_ request.Params) (interface{}, *response.Error) { port, err := s.coreServer.Port() if err != nil { return nil, response.NewInternalServerError("Cannot fetch tcp port", err) } return result.Version{ TCPPort: port, Nonce: s.coreServer.ID(), UserAgent: s.coreServer.UserAgent, }, nil } func (s *Server) getPeers(_ request.Params) (interface{}, *response.Error) { peers := result.NewGetPeers() peers.AddUnconnected(s.coreServer.UnconnectedPeers()) peers.AddConnected(s.coreServer.ConnectedPeers()) peers.AddBad(s.coreServer.BadPeers()) return peers, nil } func (s *Server) getRawMempool(_ request.Params) (interface{}, *response.Error) { mp := s.chain.GetMemPool() hashList := make([]util.Uint256, 0) for _, item := range mp.GetVerifiedTransactions() { hashList = append(hashList, item.Hash()) } return hashList, nil } func (s *Server) validateAddress(reqParams request.Params) (interface{}, *response.Error) { param, ok := reqParams.Value(0) if !ok { return nil, response.ErrInvalidParams } return validateAddress(param.Value), nil } // getApplicationLog returns the contract log based on the specified txid. func (s *Server) getApplicationLog(reqParams request.Params) (interface{}, *response.Error) { param, ok := reqParams.Value(0) if !ok { return nil, response.ErrInvalidParams } txHash, err := param.GetUint256() if err != nil { return nil, response.ErrInvalidParams } appExecResult, err := s.chain.GetAppExecResult(txHash) if err != nil { return nil, response.NewRPCError("Unknown transaction", "", nil) } return result.NewApplicationLog(appExecResult), nil } func (s *Server) getNEP5Balances(ps request.Params) (interface{}, *response.Error) { p, ok := ps.ValueWithType(0, request.StringT) if !ok { return nil, response.ErrInvalidParams } u, err := p.GetUint160FromHex() if err != nil { return nil, response.ErrInvalidParams } as := s.chain.GetNEP5Balances(u) bs := &result.NEP5Balances{ Address: address.Uint160ToString(u), Balances: []result.NEP5Balance{}, } if as != nil { cache := make(map[util.Uint160]int64) for h, bal := range as.Trackers { dec, err := s.getDecimals(h, cache) if err != nil { continue } amount := amountToString(bal.Balance, dec) bs.Balances = append(bs.Balances, result.NEP5Balance{ Asset: h, Amount: amount, LastUpdated: bal.LastUpdatedBlock, }) } } return bs, nil } func (s *Server) getNEP5Transfers(ps request.Params) (interface{}, *response.Error) { p, ok := ps.ValueWithType(0, request.StringT) if !ok { return nil, response.ErrInvalidParams } u, err := p.GetUint160FromAddress() if err != nil { return nil, response.ErrInvalidParams } bs := &result.NEP5Transfers{ Address: address.Uint160ToString(u), Received: []result.NEP5Transfer{}, Sent: []result.NEP5Transfer{}, } lg := s.chain.GetNEP5TransferLog(u) cache := make(map[util.Uint160]int64) err = lg.ForEach(func(tr *state.NEP5Transfer) error { transfer := result.NEP5Transfer{ Timestamp: tr.Timestamp, Asset: tr.Asset, Index: tr.Block, TxHash: tr.Tx, } d, err := s.getDecimals(tr.Asset, cache) if err != nil { return nil } if tr.Amount > 0 { // token was received transfer.Amount = amountToString(tr.Amount, d) if !tr.From.Equals(util.Uint160{}) { transfer.Address = address.Uint160ToString(tr.From) } bs.Received = append(bs.Received, transfer) return nil } transfer.Amount = amountToString(-tr.Amount, d) if !tr.To.Equals(util.Uint160{}) { transfer.Address = address.Uint160ToString(tr.To) } bs.Sent = append(bs.Sent, transfer) return nil }) if err != nil { return nil, response.NewInternalServerError("invalid NEP5 transfer log", err) } return bs, nil } func amountToString(amount int64, decimals int64) string { if decimals == 0 { return strconv.FormatInt(amount, 10) } pow := int64(math.Pow10(int(decimals))) q := amount / pow r := amount % pow if r == 0 { return strconv.FormatInt(q, 10) } fs := fmt.Sprintf("%%d.%%0%dd", decimals) return fmt.Sprintf(fs, q, r) } func (s *Server) getDecimals(h util.Uint160, cache map[util.Uint160]int64) (int64, *response.Error) { if d, ok := cache[h]; ok { return d, nil } script, err := request.CreateFunctionInvocationScript(h, request.Params{ { Type: request.StringT, Value: "decimals", }, { Type: request.ArrayT, Value: []request.Param{}, }, }) if err != nil { return 0, response.NewInternalServerError("Can't create script", err) } res := s.runScriptInVM(script, nil) if res == nil || res.State != "HALT" || len(res.Stack) == 0 { return 0, response.NewInternalServerError("execution error", errors.New("no result")) } var d int64 switch item := res.Stack[len(res.Stack)-1]; item.Type { case smartcontract.IntegerType: d = item.Value.(int64) case smartcontract.ByteArrayType: d = bigint.FromBytes(item.Value.([]byte)).Int64() default: return 0, response.NewInternalServerError("invalid result", errors.New("not an integer")) } if d < 0 { return 0, response.NewInternalServerError("incorrect result", errors.New("negative result")) } cache[h] = d return d, nil } func (s *Server) contractIDFromParam(param *request.Param) (int32, *response.Error) { var result int32 switch param.Type { case request.StringT: var err error scriptHash, err := param.GetUint160FromHex() if err != nil { return 0, response.ErrInvalidParams } cs := s.chain.GetContractState(scriptHash) if cs == nil { return 0, response.ErrUnknown } result = cs.ID case request.NumberT: id, err := param.GetInt() if err != nil { return 0, response.ErrInvalidParams } result = int32(id) default: return 0, response.ErrInvalidParams } return result, nil } func (s *Server) getStorage(ps request.Params) (interface{}, *response.Error) { param, ok := ps.Value(0) if !ok { return nil, response.ErrInvalidParams } id, rErr := s.contractIDFromParam(param) if rErr == response.ErrUnknown { return nil, nil } if rErr != nil { return nil, rErr } param, ok = ps.Value(1) if !ok { return nil, response.ErrInvalidParams } key, err := param.GetBytesHex() if err != nil { return nil, response.ErrInvalidParams } item := s.chain.GetStorageItem(id, key) if item == nil { return nil, nil } return hex.EncodeToString(item.Value), nil } func (s *Server) getrawtransaction(reqParams request.Params) (interface{}, *response.Error) { var resultsErr *response.Error var results interface{} if param0, ok := reqParams.Value(0); !ok { return nil, response.ErrInvalidParams } else if txHash, err := param0.GetUint256(); err != nil { resultsErr = response.ErrInvalidParams } else if tx, height, err := s.chain.GetTransaction(txHash); err != nil { err = errors.Wrapf(err, "Invalid transaction hash: %s", txHash) return nil, response.NewRPCError("Unknown transaction", err.Error(), err) } else if len(reqParams) >= 2 { _header := s.chain.GetHeaderHash(int(height)) header, err := s.chain.GetHeader(_header) if err != nil { resultsErr = response.NewInvalidParamsError(err.Error(), err) } param1, _ := reqParams.Value(1) switch v := param1.Value.(type) { case int, float64, bool, string: if v == 0 || v == "0" || v == 0.0 || v == false || v == "false" { results = hex.EncodeToString(tx.Bytes()) } else { results = result.NewTransactionOutputRaw(tx, header, s.chain) } default: results = result.NewTransactionOutputRaw(tx, header, s.chain) } } else { results = hex.EncodeToString(tx.Bytes()) } return results, resultsErr } func (s *Server) getTransactionHeight(ps request.Params) (interface{}, *response.Error) { p, ok := ps.Value(0) if !ok { return nil, response.ErrInvalidParams } h, err := p.GetUint256() if err != nil { return nil, response.ErrInvalidParams } _, height, err := s.chain.GetTransaction(h) if err != nil { return nil, response.NewRPCError("unknown transaction", "", nil) } return height, nil } // getContractState returns contract state (contract information, according to the contract script hash). func (s *Server) getContractState(reqParams request.Params) (interface{}, *response.Error) { var results interface{} param, ok := reqParams.ValueWithType(0, request.StringT) if !ok { return nil, response.ErrInvalidParams } else if scriptHash, err := param.GetUint160FromHex(); err != nil { return nil, response.ErrInvalidParams } else { cs := s.chain.GetContractState(scriptHash) if cs == nil { return nil, response.NewRPCError("Unknown contract", "", nil) } results = cs } return results, nil } // getBlockSysFee returns the system fees of the block, based on the specified index. func (s *Server) getBlockSysFee(reqParams request.Params) (interface{}, *response.Error) { param, ok := reqParams.ValueWithType(0, request.NumberT) if !ok { return 0, response.ErrInvalidParams } num, err := s.blockHeightFromParam(param) if err != nil { return 0, response.NewRPCError("Invalid height", "", nil) } headerHash := s.chain.GetHeaderHash(num) block, errBlock := s.chain.GetBlock(headerHash) if errBlock != nil { return 0, response.NewRPCError(errBlock.Error(), "", nil) } var blockSysFee util.Fixed8 for _, tx := range block.Transactions { blockSysFee += tx.SystemFee } return blockSysFee, nil } // getBlockHeader returns the corresponding block header information according to the specified script hash. func (s *Server) getBlockHeader(reqParams request.Params) (interface{}, *response.Error) { var verbose bool param, ok := reqParams.Value(0) if !ok { return nil, response.ErrInvalidParams } hash, respErr := s.blockHashFromParam(param) if respErr != nil { return nil, respErr } param, ok = reqParams.ValueWithType(1, request.NumberT) if ok { v, err := param.GetInt() if err != nil { return nil, response.ErrInvalidParams } verbose = v != 0 } h, err := s.chain.GetHeader(hash) if err != nil { return nil, response.NewRPCError("unknown block", "", nil) } if verbose { return result.NewHeader(h, s.chain), nil } buf := io.NewBufBinWriter() h.EncodeBinary(buf.BinWriter) if buf.Err != nil { return nil, response.NewInternalServerError("encoding error", buf.Err) } return hex.EncodeToString(buf.Bytes()), nil } // getUnclaimedGas returns unclaimed GAS amount of the specified address. func (s *Server) getUnclaimedGas(ps request.Params) (interface{}, *response.Error) { p, ok := ps.ValueWithType(0, request.StringT) if !ok { return nil, response.ErrInvalidParams } u, err := p.GetUint160FromAddress() if err != nil { return nil, response.ErrInvalidParams } neo, neoHeight := s.chain.GetGoverningTokenBalance(u) if neo == 0 { return "0", nil } gas := s.chain.CalculateClaimable(int64(neo), neoHeight, s.chain.BlockHeight()+1) // +1 as in C#, for the next block. return strconv.FormatInt(int64(gas), 10), nil // It's not represented as Fixed8 in C#. } // getValidators returns the current NEO consensus nodes information and voting status. func (s *Server) getValidators(_ request.Params) (interface{}, *response.Error) { var validators keys.PublicKeys validators, err := s.chain.GetValidators() if err != nil { return nil, response.NewRPCError("can't get validators", "", err) } enrollments, err := s.chain.GetEnrollments() if err != nil { return nil, response.NewRPCError("can't get enrollments", "", err) } var res []result.Validator for _, v := range enrollments { res = append(res, result.Validator{ PublicKey: *v.Key, Votes: v.Votes.Int64(), Active: validators.Contains(v.Key), }) } return res, nil } // invokeFunction implements the `invokeFunction` RPC call. func (s *Server) invokeFunction(reqParams request.Params) (interface{}, *response.Error) { scriptHashHex, ok := reqParams.ValueWithType(0, request.StringT) if !ok { return nil, response.ErrInvalidParams } scriptHash, err := scriptHashHex.GetUint160FromHex() if err != nil { return nil, response.ErrInvalidParams } tx := &transaction.Transaction{} checkWitnessHashesIndex := len(reqParams) if checkWitnessHashesIndex > 3 { cosigners, err := reqParams[3].GetCosigners() if err != nil { return nil, response.ErrInvalidParams } tx.Cosigners = cosigners checkWitnessHashesIndex-- } script, err := request.CreateFunctionInvocationScript(scriptHash, reqParams[1:checkWitnessHashesIndex]) if err != nil { return nil, response.NewInternalServerError("can't create invocation script", err) } return s.runScriptInVM(script, tx), nil } // invokescript implements the `invokescript` RPC call. func (s *Server) invokescript(reqParams request.Params) (interface{}, *response.Error) { if len(reqParams) < 1 { return nil, response.ErrInvalidParams } script, err := reqParams[0].GetBytesHex() if err != nil { return nil, response.ErrInvalidParams } tx := &transaction.Transaction{} if len(reqParams) > 1 { cosigners, err := reqParams[1].GetCosigners() if err != nil { return nil, response.ErrInvalidParams } tx.Cosigners = cosigners } return s.runScriptInVM(script, tx), nil } // runScriptInVM runs given script in a new test VM and returns the invocation // result. func (s *Server) runScriptInVM(script []byte, tx *transaction.Transaction) *result.Invoke { vm := s.chain.GetTestVM(tx) vm.GasLimit = s.config.MaxGasInvoke vm.LoadScriptWithFlags(script, smartcontract.All) _ = vm.Run() result := &result.Invoke{ State: vm.State(), GasConsumed: vm.GasConsumed().String(), Script: hex.EncodeToString(script), Stack: vm.Estack().ToContractParameters(), } return result } // submitBlock broadcasts a raw block over the NEO network. func (s *Server) submitBlock(reqParams request.Params) (interface{}, *response.Error) { param, ok := reqParams.ValueWithType(0, request.StringT) if !ok { return nil, response.ErrInvalidParams } blockBytes, err := param.GetBytesHex() if err != nil { return nil, response.ErrInvalidParams } b := block.New(s.network) r := io.NewBinReaderFromBuf(blockBytes) b.DecodeBinary(r) if r.Err != nil { return nil, response.ErrInvalidParams } err = s.chain.AddBlock(b) if err != nil { switch err { case core.ErrInvalidBlockIndex, core.ErrAlreadyExists: return nil, response.ErrAlreadyExists default: return nil, response.ErrValidationFailed } } return true, nil } func (s *Server) sendrawtransaction(reqParams request.Params) (interface{}, *response.Error) { var resultsErr *response.Error var results interface{} if len(reqParams) < 1 { return nil, response.ErrInvalidParams } else if byteTx, err := reqParams[0].GetBytesHex(); err != nil { return nil, response.ErrInvalidParams } else { tx, err := transaction.NewTransactionFromBytes(s.network, byteTx) if err != nil { return nil, response.ErrInvalidParams } relayReason := s.coreServer.RelayTxn(tx) switch relayReason { case network.RelaySucceed: results = true case network.RelayAlreadyExists: resultsErr = response.ErrAlreadyExists case network.RelayOutOfMemory: resultsErr = response.ErrOutOfMemory case network.RelayUnableToVerify: resultsErr = response.ErrUnableToVerify case network.RelayInvalid: resultsErr = response.ErrValidationFailed case network.RelayPolicyFail: resultsErr = response.ErrPolicyFail default: resultsErr = response.ErrUnknown } } return results, resultsErr } // subscribe handles subscription requests from websocket clients. func (s *Server) subscribe(reqParams request.Params, sub *subscriber) (interface{}, *response.Error) { p, ok := reqParams.Value(0) if !ok { return nil, response.ErrInvalidParams } streamName, err := p.GetString() if err != nil { return nil, response.ErrInvalidParams } event, err := response.GetEventIDFromString(streamName) if err != nil || event == response.MissedEventID { return nil, response.ErrInvalidParams } // Optional filter. var filter interface{} p, ok = reqParams.Value(1) if ok { switch event { case response.BlockEventID: if p.Type != request.BlockFilterT { return nil, response.ErrInvalidParams } case response.TransactionEventID: if p.Type != request.TxFilterT { return nil, response.ErrInvalidParams } case response.NotificationEventID: if p.Type != request.NotificationFilterT { return nil, response.ErrInvalidParams } case response.ExecutionEventID: if p.Type != request.ExecutionFilterT { return nil, response.ErrInvalidParams } } filter = p.Value } s.subsLock.Lock() defer s.subsLock.Unlock() select { case <-s.shutdown: return nil, response.NewInternalServerError("server is shutting down", nil) default: } var id int for ; id < len(sub.feeds); id++ { if sub.feeds[id].event == response.InvalidEventID { break } } if id == len(sub.feeds) { return nil, response.NewInternalServerError("maximum number of subscriptions is reached", nil) } sub.feeds[id].event = event sub.feeds[id].filter = filter s.subscribeToChannel(event) return strconv.FormatInt(int64(id), 10), nil } // subscribeToChannel subscribes RPC server to appropriate chain events if // it's not yet subscribed for them. It's supposed to be called with s.subsLock // taken by the caller. func (s *Server) subscribeToChannel(event response.EventID) { switch event { case response.BlockEventID: if s.blockSubs == 0 { s.chain.SubscribeForBlocks(s.blockCh) } s.blockSubs++ case response.TransactionEventID: if s.transactionSubs == 0 { s.chain.SubscribeForTransactions(s.transactionCh) } s.transactionSubs++ case response.NotificationEventID: if s.notificationSubs == 0 { s.chain.SubscribeForNotifications(s.notificationCh) } s.notificationSubs++ case response.ExecutionEventID: if s.executionSubs == 0 { s.chain.SubscribeForExecutions(s.executionCh) } s.executionSubs++ } } // unsubscribe handles unsubscription requests from websocket clients. func (s *Server) unsubscribe(reqParams request.Params, sub *subscriber) (interface{}, *response.Error) { p, ok := reqParams.Value(0) if !ok { return nil, response.ErrInvalidParams } id, err := p.GetInt() if err != nil || id < 0 { return nil, response.ErrInvalidParams } s.subsLock.Lock() defer s.subsLock.Unlock() if len(sub.feeds) <= id || sub.feeds[id].event == response.InvalidEventID { return nil, response.ErrInvalidParams } event := sub.feeds[id].event sub.feeds[id].event = response.InvalidEventID sub.feeds[id].filter = nil s.unsubscribeFromChannel(event) return true, nil } // unsubscribeFromChannel unsubscribes RPC server from appropriate chain events // if there are no other subscribers for it. It's supposed to be called with // s.subsLock taken by the caller. func (s *Server) unsubscribeFromChannel(event response.EventID) { switch event { case response.BlockEventID: s.blockSubs-- if s.blockSubs == 0 { s.chain.UnsubscribeFromBlocks(s.blockCh) } case response.TransactionEventID: s.transactionSubs-- if s.transactionSubs == 0 { s.chain.UnsubscribeFromTransactions(s.transactionCh) } case response.NotificationEventID: s.notificationSubs-- if s.notificationSubs == 0 { s.chain.UnsubscribeFromNotifications(s.notificationCh) } case response.ExecutionEventID: s.executionSubs-- if s.executionSubs == 0 { s.chain.UnsubscribeFromExecutions(s.executionCh) } } } func (s *Server) handleSubEvents() { b, err := json.Marshal(response.Notification{ JSONRPC: request.JSONRPCVersion, Event: response.MissedEventID, Payload: make([]interface{}, 0), }) if err != nil { s.log.Error("fatal: failed to marshal overflow event", zap.Error(err)) return } overflowMsg, err := websocket.NewPreparedMessage(websocket.TextMessage, b) if err != nil { s.log.Error("fatal: failed to prepare overflow message", zap.Error(err)) return } chloop: for { var resp = response.Notification{ JSONRPC: request.JSONRPCVersion, Payload: make([]interface{}, 1), } var msg *websocket.PreparedMessage select { case <-s.shutdown: break chloop case b := <-s.blockCh: resp.Event = response.BlockEventID resp.Payload[0] = b case execution := <-s.executionCh: resp.Event = response.ExecutionEventID resp.Payload[0] = result.NewApplicationLog(execution) case notification := <-s.notificationCh: resp.Event = response.NotificationEventID resp.Payload[0] = result.StateEventToResultNotification(*notification) case tx := <-s.transactionCh: resp.Event = response.TransactionEventID resp.Payload[0] = tx } s.subsLock.RLock() subloop: for sub := range s.subscribers { if sub.overflown.Load() { continue } for i := range sub.feeds { if sub.feeds[i].Matches(&resp) { if msg == nil { b, err = json.Marshal(resp) if err != nil { s.log.Error("failed to marshal notification", zap.Error(err), zap.String("type", resp.Event.String())) break subloop } msg, err = websocket.NewPreparedMessage(websocket.TextMessage, b) if err != nil { s.log.Error("failed to prepare notification message", zap.Error(err), zap.String("type", resp.Event.String())) break subloop } } select { case sub.writer <- msg: default: sub.overflown.Store(true) // MissedEvent is to be delivered eventually. go func(sub *subscriber) { sub.writer <- overflowMsg sub.overflown.Store(false) }(sub) } // The message is sent only once per subscriber. break } } } s.subsLock.RUnlock() } // It's important to do it with lock held because no subscription routine // should be running concurrently to this one. And even if one is to run // after unlock, it'll see closed s.shutdown and won't subscribe. s.subsLock.Lock() // There might be no subscription in reality, but it's not a problem as // core.Blockchain allows unsubscribing non-subscribed channels. s.chain.UnsubscribeFromBlocks(s.blockCh) s.chain.UnsubscribeFromTransactions(s.transactionCh) s.chain.UnsubscribeFromNotifications(s.notificationCh) s.chain.UnsubscribeFromExecutions(s.executionCh) s.subsLock.Unlock() drainloop: for { select { case <-s.blockCh: case <-s.executionCh: case <-s.notificationCh: case <-s.transactionCh: default: break drainloop } } // It's not required closing these, but since they're drained already // this is safe and it also allows to give a signal to Shutdown routine. close(s.blockCh) close(s.transactionCh) close(s.notificationCh) close(s.executionCh) } func (s *Server) blockHeightFromParam(param *request.Param) (int, *response.Error) { num, err := param.GetInt() if err != nil { return 0, nil } if num < 0 || num > int(s.chain.BlockHeight()) { return 0, invalidBlockHeightError(0, num) } return num, nil } func (s *Server) packResponseToRaw(r *request.In, result interface{}, respErr *response.Error) response.Raw { resp := response.Raw{ HeaderAndError: response.HeaderAndError{ Header: response.Header{ JSONRPC: r.JSONRPC, ID: r.RawID, }, }, } if respErr != nil { resp.Error = respErr } else { resJSON, err := json.Marshal(result) if err != nil { s.log.Error("failed to marshal result", zap.Error(err), zap.String("method", r.Method)) resp.Error = response.NewInternalServerError("failed to encode result", err) } else { resp.Result = resJSON } } return resp } // logRequestError is a request error logger. func (s *Server) logRequestError(r *request.In, jsonErr *response.Error) { logFields := []zap.Field{ zap.Error(jsonErr.Cause), zap.String("method", r.Method), } params, err := r.Params() if err == nil { logFields = append(logFields, zap.Any("params", params)) } s.log.Error("Error encountered with rpc request", logFields...) } // writeHTTPErrorResponse writes an error response to the ResponseWriter. func (s *Server) writeHTTPErrorResponse(r *request.In, w http.ResponseWriter, jsonErr *response.Error) { resp := s.packResponseToRaw(r, nil, jsonErr) s.writeHTTPServerResponse(r, w, resp) } func (s *Server) writeHTTPServerResponse(r *request.In, w http.ResponseWriter, resp response.Raw) { // Errors can happen in many places and we can only catch ALL of them here. if resp.Error != nil { s.logRequestError(r, resp.Error) w.WriteHeader(resp.Error.HTTPCode) } w.Header().Set("Content-Type", "application/json; charset=utf-8") if s.config.EnableCORSWorkaround { w.Header().Set("Access-Control-Allow-Origin", "*") w.Header().Set("Access-Control-Allow-Headers", "Content-Type, Access-Control-Allow-Headers, Authorization, X-Requested-With") } encoder := json.NewEncoder(w) err := encoder.Encode(resp) if err != nil { s.log.Error("Error encountered while encoding response", zap.String("err", err.Error()), zap.String("method", r.Method)) } } // validateAddress verifies that the address is a correct NEO address // see https://docs.neo.org/en-us/node/cli/2.9.4/api/validateaddress.html func validateAddress(addr interface{}) result.ValidateAddress { resp := result.ValidateAddress{Address: addr} if addr, ok := addr.(string); ok { _, err := address.StringToUint160(addr) resp.IsValid = (err == nil) } return resp }