package lntest import ( "bytes" "encoding/hex" "flag" "fmt" "io" "io/ioutil" "net" "os" "os/exec" "path/filepath" "strconv" "sync" "time" "golang.org/x/net/context" "google.golang.org/grpc" "google.golang.org/grpc/credentials" macaroon "gopkg.in/macaroon.v1" "github.com/go-errors/errors" "github.com/lightningnetwork/lnd/lnrpc" "github.com/lightningnetwork/lnd/macaroons" "github.com/roasbeef/btcd/chaincfg" "github.com/roasbeef/btcd/chaincfg/chainhash" "github.com/roasbeef/btcd/rpcclient" "github.com/roasbeef/btcd/wire" ) var ( // numActiveNodes is the number of active nodes within the test network. numActiveNodes = 0 // defaultNodePort is the initial p2p port which will be used by the // first created lightning node to listen on for incoming p2p // connections. Subsequent allocated ports for future lighting nodes // instances will be monotonically increasing odd numbers calculated as // such: defaultP2pPort + (2 * harness.nodeNum). defaultNodePort = 19555 // defaultClientPort is the initial rpc port which will be used by the // first created lightning node to listen on for incoming rpc // connections. Subsequent allocated ports for future rpc harness // instances will be monotonically increasing even numbers calculated // as such: defaultP2pPort + (2 * harness.nodeNum). defaultClientPort = 19556 // logOutput is a flag that can be set to append the output from the // seed nodes to log files. logOutput = flag.Bool("logoutput", false, "log output from node n to file outputn.log") // trickleDelay is the amount of time in milliseconds between each // release of announcements by AuthenticatedGossiper to the network. trickleDelay = 50 ) // generateListeningPorts returns two strings representing ports to listen on // designated for the current lightning network test. If there haven't been any // test instances created, the default ports are used. Otherwise, in order to // support multiple test nodes running at once, the p2p and rpc port are // incremented after each initialization. func generateListeningPorts() (int, int) { var p2p, rpc int if numActiveNodes == 0 { p2p = defaultNodePort rpc = defaultClientPort } else { p2p = defaultNodePort + (2 * numActiveNodes) rpc = defaultClientPort + (2 * numActiveNodes) } return p2p, rpc } type nodeConfig struct { RPCConfig *rpcclient.ConnConfig NetParams *chaincfg.Params BaseDir string ExtraArgs []string DataDir string LogDir string TLSCertPath string TLSKeyPath string AdminMacPath string ReadMacPath string P2PPort int RPCPort int } func (cfg nodeConfig) P2PAddr() string { return net.JoinHostPort("127.0.0.1", strconv.Itoa(cfg.P2PPort)) } func (cfg nodeConfig) RPCAddr() string { return net.JoinHostPort("127.0.0.1", strconv.Itoa(cfg.RPCPort)) } func (cfg nodeConfig) DBPath() string { return filepath.Join(cfg.DataDir, cfg.NetParams.Name, "bitcoin/channel.db") } // genArgs generates a slice of command line arguments from the lightning node // config struct. func (cfg nodeConfig) genArgs() []string { var args []string switch cfg.NetParams { case &chaincfg.TestNet3Params: args = append(args, "--bitcoin.testnet") case &chaincfg.SimNetParams: args = append(args, "--bitcoin.simnet") case &chaincfg.RegressionNetParams: args = append(args, "--bitcoin.regtest") } encodedCert := hex.EncodeToString(cfg.RPCConfig.Certificates) args = append(args, "--bitcoin.active") args = append(args, "--nobootstrap") args = append(args, "--noencryptwallet") args = append(args, "--debuglevel=debug") args = append(args, "--defaultchanconfs=1") args = append(args, fmt.Sprintf("--bitcoin.rpchost=%v", cfg.RPCConfig.Host)) args = append(args, fmt.Sprintf("--bitcoin.rpcuser=%v", cfg.RPCConfig.User)) args = append(args, fmt.Sprintf("--bitcoin.rpcpass=%v", cfg.RPCConfig.Pass)) args = append(args, fmt.Sprintf("--bitcoin.rawrpccert=%v", encodedCert)) args = append(args, fmt.Sprintf("--rpcport=%v", cfg.RPCPort)) args = append(args, fmt.Sprintf("--peerport=%v", cfg.P2PPort)) args = append(args, fmt.Sprintf("--logdir=%v", cfg.LogDir)) args = append(args, fmt.Sprintf("--datadir=%v", cfg.DataDir)) args = append(args, fmt.Sprintf("--tlscertpath=%v", cfg.TLSCertPath)) args = append(args, fmt.Sprintf("--tlskeypath=%v", cfg.TLSKeyPath)) args = append(args, fmt.Sprintf("--configfile=%v", cfg.DataDir)) args = append(args, fmt.Sprintf("--adminmacaroonpath=%v", cfg.AdminMacPath)) args = append(args, fmt.Sprintf("--readonlymacaroonpath=%v", cfg.ReadMacPath)) args = append(args, fmt.Sprintf("--externalip=%s", cfg.P2PAddr())) args = append(args, fmt.Sprintf("--trickledelay=%v", trickleDelay)) if cfg.ExtraArgs != nil { args = append(args, cfg.ExtraArgs...) } return args } // HarnessNode represents an instance of lnd running within our test network // harness. Each HarnessNode instance also fully embeds an RPC client in // order to pragmatically drive the node. type HarnessNode struct { cfg *nodeConfig // NodeID is a unique identifier for the node within a NetworkHarness. NodeID int // PubKey is the serialized compressed identity public key of the node. // This field will only be populated once the node itself has been // started via the start() method. PubKey [33]byte PubKeyStr string cmd *exec.Cmd pidFile string // processExit is a channel that's closed once it's detected that the // process this instance of HarnessNode is bound to has exited. processExit chan struct{} chanWatchRequests chan *chanWatchRequest quit chan struct{} wg sync.WaitGroup lnrpc.LightningClient } // Assert *HarnessNode implements the lnrpc.LightningClient interface. var _ lnrpc.LightningClient = (*HarnessNode)(nil) // newNode creates a new test lightning node instance from the passed config. func newNode(cfg nodeConfig) (*HarnessNode, error) { if cfg.BaseDir == "" { var err error cfg.BaseDir, err = ioutil.TempDir("", "lndtest-node") if err != nil { return nil, err } } cfg.DataDir = filepath.Join(cfg.BaseDir, "data") cfg.LogDir = filepath.Join(cfg.BaseDir, "log") cfg.TLSCertPath = filepath.Join(cfg.DataDir, "tls.cert") cfg.TLSKeyPath = filepath.Join(cfg.DataDir, "tls.key") cfg.AdminMacPath = filepath.Join(cfg.DataDir, "admin.macaroon") cfg.ReadMacPath = filepath.Join(cfg.DataDir, "readonly.macaroon") cfg.P2PPort, cfg.RPCPort = generateListeningPorts() nodeNum := numActiveNodes numActiveNodes++ return &HarnessNode{ cfg: &cfg, NodeID: nodeNum, chanWatchRequests: make(chan *chanWatchRequest), }, nil } // DBPath returns the filepath to the channeldb database file for this node. func (hn *HarnessNode) DBPath() string { return hn.cfg.DBPath() } // Start launches a new process running lnd. Additionally, the PID of the // launched process is saved in order to possibly kill the process forcibly // later. // // This may not clean up properly if an error is returned, so the caller should // call shutdown() regardless of the return value. func (hn *HarnessNode) start(lndError chan<- error) error { hn.quit = make(chan struct{}) args := hn.cfg.genArgs() hn.cmd = exec.Command("lnd", args...) // Redirect stderr output to buffer var errb bytes.Buffer hn.cmd.Stderr = &errb // If the logoutput flag is passed, redirect output from the nodes to // log files. if *logOutput { logFile := fmt.Sprintf("output%d.log", hn.NodeID) // Create file if not exists, otherwise append. file, err := os.OpenFile(logFile, os.O_WRONLY|os.O_APPEND|os.O_CREATE, 0666) if err != nil { return err } // Pass node's stderr to both errb and the file. w := io.MultiWriter(&errb, file) hn.cmd.Stderr = w // Pass the node's stdout only to the file. hn.cmd.Stdout = file } if err := hn.cmd.Start(); err != nil { return err } // Launch a new goroutine which that bubbles up any potential fatal // process errors to the goroutine running the tests. hn.processExit = make(chan struct{}) go func() { err := hn.cmd.Wait() if err != nil { lndError <- errors.Errorf("%v\n%v\n", err, errb.String()) } // Signal any onlookers that this process has exited. close(hn.processExit) }() // Write process ID to a file. if err := hn.writePidFile(); err != nil { hn.cmd.Process.Kill() return err } // Since Stop uses the LightningClient to stop the node, if we fail to get a // connected client, we have to kill the process. conn, err := hn.connectRPC() if err != nil { hn.cmd.Process.Kill() return err } hn.LightningClient = lnrpc.NewLightningClient(conn) // Obtain the lnid of this node for quick identification purposes. ctxb := context.Background() info, err := hn.GetInfo(ctxb, &lnrpc.GetInfoRequest{}) if err != nil { return err } hn.PubKeyStr = info.IdentityPubkey pubkey, err := hex.DecodeString(info.IdentityPubkey) if err != nil { return err } copy(hn.PubKey[:], pubkey) // Launch the watcher that'll hook into graph related topology change // from the PoV of this node. hn.wg.Add(1) go hn.lightningNetworkWatcher() return nil } // writePidFile writes the process ID of the running lnd process to a .pid file. func (hn *HarnessNode) writePidFile() error { filePath := filepath.Join(hn.cfg.BaseDir, fmt.Sprintf("%v.pid", hn.NodeID)) pid, err := os.Create(filePath) if err != nil { return err } defer pid.Close() _, err = fmt.Fprintf(pid, "%v\n", hn.cmd.Process.Pid) if err != nil { return err } hn.pidFile = filePath return nil } // connectRPC uses the TLS certificate and admin macaroon files written by the // lnd node to create a gRPC client connection. func (hn *HarnessNode) connectRPC() (*grpc.ClientConn, error) { // Wait until TLS certificate and admin macaroon are created before // using them, up to 20 sec. tlsTimeout := time.After(30 * time.Second) for !fileExists(hn.cfg.TLSCertPath) || !fileExists(hn.cfg.AdminMacPath) { select { case <-tlsTimeout: return nil, fmt.Errorf("timeout waiting for TLS cert file " + "and admin macaroon file to be created after " + "20 seconds") case <-time.After(100 * time.Millisecond): } } tlsCreds, err := credentials.NewClientTLSFromFile(hn.cfg.TLSCertPath, "") if err != nil { return nil, err } macBytes, err := ioutil.ReadFile(hn.cfg.AdminMacPath) if err != nil { return nil, err } mac := &macaroon.Macaroon{} if err = mac.UnmarshalBinary(macBytes); err != nil { return nil, err } opts := []grpc.DialOption{ grpc.WithTransportCredentials(tlsCreds), grpc.WithPerRPCCredentials(macaroons.NewMacaroonCredential(mac)), grpc.WithBlock(), grpc.WithTimeout(time.Second * 20), } return grpc.Dial(hn.cfg.RPCAddr(), opts...) } // cleanup cleans up all the temporary files created by the node's process. func (hn *HarnessNode) cleanup() error { return os.RemoveAll(hn.cfg.BaseDir) } // Stop attempts to stop the active lnd process. func (hn *HarnessNode) stop() error { // Do nothing if the process is not running. if hn.processExit == nil { return nil } // If start() failed before creating a client, we will just wait for the // child process to die. if hn.LightningClient != nil { // Don't watch for error because sometimes the RPC connection gets // closed before a response is returned. req := lnrpc.StopRequest{} ctx := context.Background() hn.LightningClient.StopDaemon(ctx, &req) } // Wait for lnd process and other goroutines to exit. <-hn.processExit close(hn.quit) hn.wg.Wait() hn.quit = nil hn.processExit = nil hn.LightningClient = nil return nil } // shutdown stops the active lnd process and cleans up any temporary directories // created along the way. func (hn *HarnessNode) shutdown() error { if err := hn.stop(); err != nil { return err } if err := hn.cleanup(); err != nil { return err } return nil } // closeChanWatchRequest is a request to the lightningNetworkWatcher to be // notified once it's detected within the test Lightning Network, that a // channel has either been added or closed. type chanWatchRequest struct { chanPoint wire.OutPoint chanOpen bool eventChan chan struct{} } // lightningNetworkWatcher is a goroutine which is able to dispatch // notifications once it has been observed that a target channel has been // closed or opened within the network. In order to dispatch these // notifications, the GraphTopologySubscription client exposed as part of the // gRPC interface is used. func (hn *HarnessNode) lightningNetworkWatcher() { defer hn.wg.Done() graphUpdates := make(chan *lnrpc.GraphTopologyUpdate) hn.wg.Add(1) go func() { defer hn.wg.Done() ctxb := context.Background() req := &lnrpc.GraphTopologySubscription{} topologyClient, err := hn.SubscribeChannelGraph(ctxb, req) if err != nil { // We panic here in case of an error as failure to // create the topology client will cause all subsequent // tests to fail. panic(fmt.Errorf("unable to create topology "+ "client: %v", err)) } for { update, err := topologyClient.Recv() if err == io.EOF { return } else if err != nil { return } select { case graphUpdates <- update: case <-hn.quit: return } } }() // For each outpoint, we'll track an integer which denotes the number // of edges seen for that channel within the network. When this number // reaches 2, then it means that both edge advertisements has // propagated through the network. openChans := make(map[wire.OutPoint]int) openClients := make(map[wire.OutPoint][]chan struct{}) closedChans := make(map[wire.OutPoint]struct{}) closeClients := make(map[wire.OutPoint][]chan struct{}) for { select { // A new graph update has just been received, so we'll examine // the current set of registered clients to see if we can // dispatch any requests. case graphUpdate := <-graphUpdates: // For each new channel, we'll increment the number of // edges seen by one. for _, newChan := range graphUpdate.ChannelUpdates { txid, _ := chainhash.NewHash(newChan.ChanPoint.FundingTxid) op := wire.OutPoint{ Hash: *txid, Index: newChan.ChanPoint.OutputIndex, } openChans[op]++ // For this new channel, if the number of edges // seen is less than two, then the channel // hasn't been fully announced yet. if numEdges := openChans[op]; numEdges < 2 { continue } // Otherwise, we'll notify all the registered // clients and remove the dispatched clients. for _, eventChan := range openClients[op] { close(eventChan) } delete(openClients, op) } // For each channel closed, we'll mark that we've // detected a channel closure while lnd was pruning the // channel graph. for _, closedChan := range graphUpdate.ClosedChans { txid, _ := chainhash.NewHash(closedChan.ChanPoint.FundingTxid) op := wire.OutPoint{ Hash: *txid, Index: closedChan.ChanPoint.OutputIndex, } closedChans[op] = struct{}{} // As the channel has been closed, we'll notify // all register clients. for _, eventChan := range closeClients[op] { close(eventChan) } delete(closeClients, op) } // A new watch request, has just arrived. We'll either be able // to dispatch immediately, or need to add the client for // processing later. case watchRequest := <-hn.chanWatchRequests: targetChan := watchRequest.chanPoint // TODO(roasbeef): add update type also, checks for // multiple of 2 if watchRequest.chanOpen { // If this is a open request, then it can be // dispatched if the number of edges seen for // the channel is at least two. if numEdges := openChans[targetChan]; numEdges >= 2 { close(watchRequest.eventChan) continue } // Otherwise, we'll add this to the list of // watch open clients for this out point. openClients[targetChan] = append(openClients[targetChan], watchRequest.eventChan) continue } // If this is a close request, then it can be // immediately dispatched if we've already seen a // channel closure for this channel. if _, ok := closedChans[targetChan]; ok { close(watchRequest.eventChan) continue } // Otherwise, we'll add this to the list of close watch // clients for this out point. closeClients[targetChan] = append(closeClients[targetChan], watchRequest.eventChan) case <-hn.quit: return } } } // WaitForNetworkChannelOpen will block until a channel with the target // outpoint is seen as being fully advertised within the network. A channel is // considered "fully advertised" once both of its directional edges has been // advertised within the test Lightning Network. func (hn *HarnessNode) WaitForNetworkChannelOpen(ctx context.Context, op *lnrpc.ChannelPoint) error { eventChan := make(chan struct{}) txid, err := chainhash.NewHash(op.FundingTxid) if err != nil { return err } hn.chanWatchRequests <- &chanWatchRequest{ chanPoint: wire.OutPoint{ Hash: *txid, Index: op.OutputIndex, }, eventChan: eventChan, chanOpen: true, } select { case <-eventChan: return nil case <-ctx.Done(): return fmt.Errorf("channel not opened before timeout") } } // WaitForNetworkChannelClose will block until a channel with the target // outpoint is seen as closed within the network. A channel is considered // closed once a transaction spending the funding outpoint is seen within a // confirmed block. func (hn *HarnessNode) WaitForNetworkChannelClose(ctx context.Context, op *lnrpc.ChannelPoint) error { eventChan := make(chan struct{}) txid, err := chainhash.NewHash(op.FundingTxid) if err != nil { return err } hn.chanWatchRequests <- &chanWatchRequest{ chanPoint: wire.OutPoint{ Hash: *txid, Index: op.OutputIndex, }, eventChan: eventChan, chanOpen: false, } select { case <-eventChan: return nil case <-ctx.Done(): return fmt.Errorf("channel not closed before timeout") } } // WaitForBlockchainSync will block until the target nodes has fully // synchronized with the blockchain. If the passed context object has a set // timeout, then the goroutine will continually poll until the timeout has // elapsed. In the case that the chain isn't synced before the timeout is up, // then this function will return an error. func (hn *HarnessNode) WaitForBlockchainSync(ctx context.Context) error { errChan := make(chan error, 1) retryDelay := time.Millisecond * 100 go func() { for { select { case <-ctx.Done(): case <-hn.quit: return default: } getInfoReq := &lnrpc.GetInfoRequest{} getInfoResp, err := hn.GetInfo(ctx, getInfoReq) if err != nil { errChan <- err return } if getInfoResp.SyncedToChain { errChan <- nil return } select { case <-ctx.Done(): return case <-time.After(retryDelay): } } }() select { case <-hn.quit: return nil case err := <-errChan: return err case <-ctx.Done(): return fmt.Errorf("Timeout while waiting for blockchain sync") } } // fileExists reports whether the named file or directory exists. // This function is taken from https://github.com/btcsuite/btcd func fileExists(name string) bool { if _, err := os.Stat(name); err != nil { if os.IsNotExist(err) { return false } } return true }