package main import ( "bytes" "encoding/hex" "fmt" "io" "time" "sync" "sync/atomic" "github.com/BitfuryLightning/tools/rt/graph" "github.com/btcsuite/fastsha256" "github.com/davecgh/go-spew/spew" "github.com/lightningnetwork/lightning-onion" "github.com/lightningnetwork/lnd/channeldb" "github.com/lightningnetwork/lnd/lndc" "github.com/lightningnetwork/lnd/lnrpc" "github.com/lightningnetwork/lnd/lnwallet" "github.com/lightningnetwork/lnd/lnwire" "github.com/roasbeef/btcd/btcec" "github.com/roasbeef/btcd/txscript" "github.com/roasbeef/btcd/wire" "github.com/roasbeef/btcutil" "github.com/roasbeef/btcwallet/waddrmgr" "golang.org/x/net/context" ) var ( defaultAccount uint32 = waddrmgr.DefaultAccountNum ) // rpcServer is a gRPC, RPC front end to the lnd daemon. // TODO(roasbeef): pagination support for the list-style calls type rpcServer struct { started int32 // To be used atomically. shutdown int32 // To be used atomically. server *server wg sync.WaitGroup quit chan struct{} } // A compile time check to ensure that rpcServer fully implements the // LightningServer gRPC service. var _ lnrpc.LightningServer = (*rpcServer)(nil) // newRpcServer creates and returns a new instance of the rpcServer. func newRpcServer(s *server) *rpcServer { return &rpcServer{server: s, quit: make(chan struct{}, 1)} } // Start launches any helper goroutines required for the rpcServer // to function. func (r *rpcServer) Start() error { if atomic.AddInt32(&r.started, 1) != 1 { return nil } return nil } // Stop signals any active goroutines for a graceful closure. func (r *rpcServer) Stop() error { if atomic.AddInt32(&r.shutdown, 1) != 1 { return nil } close(r.quit) return nil } // addrPairsToOutputs converts a map describing a set of outputs to be created, // the outputs themselves. The passed map pairs up an address, to a desired // output value amount. Each address is converted to its corresponding pkScript // to be used within the constructed output(s). func addrPairsToOutputs(addrPairs map[string]int64) ([]*wire.TxOut, error) { outputs := make([]*wire.TxOut, 0, len(addrPairs)) for addr, amt := range addrPairs { addr, err := btcutil.DecodeAddress(addr, activeNetParams.Params) if err != nil { return nil, err } pkscript, err := txscript.PayToAddrScript(addr) if err != nil { return nil, err } outputs = append(outputs, wire.NewTxOut(amt, pkscript)) } return outputs, nil } // sendCoinsOnChain makes an on-chain transaction in or to send coins to one or // more addresses specified in the passed payment map. The payment map maps an // address to a specified output value to be sent to that address. func (r *rpcServer) sendCoinsOnChain(paymentMap map[string]int64) (*wire.ShaHash, error) { outputs, err := addrPairsToOutputs(paymentMap) if err != nil { return nil, err } return r.server.lnwallet.SendOutputs(outputs) } // SendCoins executes a request to send coins to a particular address. Unlike // SendMany, this RPC call only allows creating a single output at a time. func (r *rpcServer) SendCoins(ctx context.Context, in *lnrpc.SendCoinsRequest) (*lnrpc.SendCoinsResponse, error) { rpcsLog.Infof("[sendcoins] addr=%v, amt=%v", in.Addr, btcutil.Amount(in.Amount)) paymentMap := map[string]int64{in.Addr: in.Amount} txid, err := r.sendCoinsOnChain(paymentMap) if err != nil { return nil, err } rpcsLog.Infof("[sendcoins] spend generated txid: %v", txid.String()) return &lnrpc.SendCoinsResponse{Txid: txid.String()}, nil } // SendMany handles a request for a transaction create multiple specified // outputs in parallel. func (r *rpcServer) SendMany(ctx context.Context, in *lnrpc.SendManyRequest) (*lnrpc.SendManyResponse, error) { txid, err := r.sendCoinsOnChain(in.AddrToAmount) if err != nil { return nil, err } rpcsLog.Infof("[sendmany] spend generated txid: %v", txid.String()) return &lnrpc.SendManyResponse{Txid: txid.String()}, nil } // NewAddress creates a new address under control of the local wallet. func (r *rpcServer) NewAddress(ctx context.Context, in *lnrpc.NewAddressRequest) (*lnrpc.NewAddressResponse, error) { // Translate the gRPC proto address type to the wallet controller's // available address types. var addrType lnwallet.AddressType switch in.Type { case lnrpc.NewAddressRequest_WITNESS_PUBKEY_HASH: addrType = lnwallet.WitnessPubKey case lnrpc.NewAddressRequest_NESTED_PUBKEY_HASH: addrType = lnwallet.NestedWitnessPubKey case lnrpc.NewAddressRequest_PUBKEY_HASH: addrType = lnwallet.PubKeyHash } addr, err := r.server.lnwallet.NewAddress(addrType, false) if err != nil { return nil, err } rpcsLog.Infof("[newaddress] addr=%v", addr.String()) return &lnrpc.NewAddressResponse{Address: addr.String()}, nil } // ConnectPeer attempts to establish a connection to a remote peer. func (r *rpcServer) ConnectPeer(ctx context.Context, in *lnrpc.ConnectPeerRequest) (*lnrpc.ConnectPeerResponse, error) { if in.Addr == nil { return nil, fmt.Errorf("need: lnc pubkeyhash@hostname") } idAtHost := fmt.Sprintf("%v@%v", in.Addr.PubKeyHash, in.Addr.Host) rpcsLog.Debugf("[connectpeer] peer=%v", idAtHost) peerAddr, err := lndc.LnAddrFromString(idAtHost, activeNetParams.Params) if err != nil { rpcsLog.Errorf("(connectpeer): error parsing ln addr: %v", err) return nil, err } peerID, err := r.server.ConnectToPeer(peerAddr) if err != nil { rpcsLog.Errorf("(connectpeer): error connecting to peer: %v", err) return nil, err } rpcsLog.Debugf("Connected to peer: %v", peerAddr.String()) return &lnrpc.ConnectPeerResponse{peerID}, nil } // OpenChannel attempts to open a singly funded channel specified in the // request to a remote peer. func (r *rpcServer) OpenChannel(in *lnrpc.OpenChannelRequest, updateStream lnrpc.Lightning_OpenChannelServer) error { rpcsLog.Tracef("[openchannel] request to peerid(%v) "+ "allocation(us=%v, them=%v) numconfs=%v", in.TargetPeerId, in.LocalFundingAmount, in.RemoteFundingAmount, in.NumConfs) localFundingAmt := btcutil.Amount(in.LocalFundingAmount) remoteFundingAmt := btcutil.Amount(in.RemoteFundingAmount) updateChan, errChan := r.server.OpenChannel(in.TargetPeerId, in.TargetNode, localFundingAmt, remoteFundingAmt, in.NumConfs) var outpoint wire.OutPoint out: for { select { case err := <-errChan: rpcsLog.Errorf("unable to open channel to "+ "lightningID(%x) nor peerID(%v): %v", in.TargetNode, in.TargetPeerId, err) return err case fundingUpdate := <-updateChan: rpcsLog.Tracef("[openchannel] sending update: %v", fundingUpdate) if err := updateStream.Send(fundingUpdate); err != nil { return err } // If a final channel open update is being sent, then // we can break out of our recv loop as we no longer // need to process any further updates. switch update := fundingUpdate.Update.(type) { case *lnrpc.OpenStatusUpdate_ChanOpen: chanPoint := update.ChanOpen.ChannelPoint h, _ := wire.NewShaHash(chanPoint.FundingTxid) outpoint = wire.OutPoint{ Hash: *h, Index: chanPoint.OutputIndex, } break out } case <-r.quit: return nil } } rpcsLog.Tracef("[openchannel] success peerid(%v), ChannelPoint(%v)", in.TargetPeerId, outpoint) return nil } // CloseChannel attempts to close an active channel identified by its channel // point. The actions of this method can additionally be augmented to attempt // a force close after a timeout period in the case of an inactive peer. func (r *rpcServer) CloseChannel(in *lnrpc.CloseChannelRequest, updateStream lnrpc.Lightning_CloseChannelServer) error { force := in.Force index := in.ChannelPoint.OutputIndex txid, err := wire.NewShaHash(in.ChannelPoint.FundingTxid) if err != nil { rpcsLog.Errorf("[closechannel] invalid txid: %v", err) return err } targetChannelPoint := wire.NewOutPoint(txid, index) rpcsLog.Tracef("[closechannel] request for ChannelPoint(%v)", targetChannelPoint) updateChan, errChan := r.server.htlcSwitch.CloseLink(targetChannelPoint, force) out: for { select { case err := <-errChan: rpcsLog.Errorf("[closechannel] unable to close "+ "ChannelPoint(%v): %v", targetChannelPoint, err) return err case closingUpdate := <-updateChan: rpcsLog.Tracef("[closechannel] sending update: %v", closingUpdate) if err := updateStream.Send(closingUpdate); err != nil { return err } // If a final channel closing updates is being sent, // then we can break out of our dispatch loop as we no // longer need to process any further updates. switch closeUpdate := closingUpdate.Update.(type) { case *lnrpc.CloseStatusUpdate_ChanClose: h, _ := wire.NewShaHash(closeUpdate.ChanClose.ClosingTxid) rpcsLog.Infof("[closechannel] close completed: "+ "txid(%v)", h) break out } case <-r.quit: return nil } } return nil } // GetInfo serves a request to the "getinfo" RPC call. This call returns // general information concerning the lightning node including it's LN ID, // identity address, and information concerning the number of open+pending // channels. func (r *rpcServer) GetInfo(ctx context.Context, in *lnrpc.GetInfoRequest) (*lnrpc.GetInfoResponse, error) { var activeChannels uint32 serverPeers := r.server.Peers() for _, serverPeer := range serverPeers { activeChannels += uint32(len(serverPeer.ChannelSnapshots())) } pendingChannels := r.server.fundingMgr.NumPendingChannels() idPub := r.server.identityPriv.PubKey().SerializeCompressed() idAddr, err := btcutil.NewAddressPubKeyHash(btcutil.Hash160(idPub), activeNetParams.Params) if err != nil { return nil, err } return &lnrpc.GetInfoResponse{ LightningId: hex.EncodeToString(r.server.lightningID[:]), IdentityPubkey: hex.EncodeToString(idPub), IdentityAddress: idAddr.String(), NumPendingChannels: pendingChannels, NumActiveChannels: activeChannels, NumPeers: uint32(len(serverPeers)), }, nil } // ListPeers returns a verbose listing of all currently active peers. func (r *rpcServer) ListPeers(ctx context.Context, in *lnrpc.ListPeersRequest) (*lnrpc.ListPeersResponse, error) { rpcsLog.Tracef("[listpeers] request") serverPeers := r.server.Peers() resp := &lnrpc.ListPeersResponse{ Peers: make([]*lnrpc.Peer, 0, len(serverPeers)), } for _, serverPeer := range serverPeers { // TODO(roasbeef): add a snapshot method which grabs peer read mtx lnID := hex.EncodeToString(serverPeer.lightningID[:]) peer := &lnrpc.Peer{ LightningId: lnID, PeerId: serverPeer.id, Address: serverPeer.conn.RemoteAddr().String(), Inbound: serverPeer.inbound, BytesRecv: atomic.LoadUint64(&serverPeer.bytesReceived), BytesSent: atomic.LoadUint64(&serverPeer.bytesSent), } resp.Peers = append(resp.Peers, peer) } rpcsLog.Debugf("[listpeers] yielded %v peers", serverPeers) return resp, nil } // WalletBalance returns the sum of all confirmed unspent outputs under control // by the wallet. This method can be modified by having the request specify // only witness outputs should be factored into the final output sum. // TODO(roasbeef): split into total and confirmed/unconfirmed // TODO(roasbeef): add async hooks into wallet balance changes func (r *rpcServer) WalletBalance(ctx context.Context, in *lnrpc.WalletBalanceRequest) (*lnrpc.WalletBalanceResponse, error) { balance, err := r.server.lnwallet.ConfirmedBalance(1, in.WitnessOnly) if err != nil { return nil, err } rpcsLog.Debugf("[walletbalance] balance=%v", balance) return &lnrpc.WalletBalanceResponse{balance.ToBTC()}, nil } // ChannelBalance returns the total available channel flow across all open // channels in satoshis. func (r *rpcServer) ChannelBalance(ctx context.Context, in *lnrpc.ChannelBalanceRequest) (*lnrpc.ChannelBalanceResponse, error) { var balance btcutil.Amount for _, peer := range r.server.Peers() { for _, snapshot := range peer.ChannelSnapshots() { balance += snapshot.LocalBalance } } return &lnrpc.ChannelBalanceResponse{Balance: int64(balance)}, nil } // PendingChannels returns a list of all the channels that are currently // considered "pending". A channel is pending if it has finished the funding // workflow and is waiting for confirmations for the funding txn, or is in the // process of closure, either initiated cooperatively or non-coopertively. func (r *rpcServer) PendingChannels(ctx context.Context, in *lnrpc.PendingChannelRequest) (*lnrpc.PendingChannelResponse, error) { both := in.Status == lnrpc.ChannelStatus_ALL includeOpen := (in.Status == lnrpc.ChannelStatus_OPENING) || both includeClose := (in.Status == lnrpc.ChannelStatus_CLOSING) || both rpcsLog.Debugf("[pendingchannels] %v", in.Status) var pendingChannels []*lnrpc.PendingChannelResponse_PendingChannel if includeOpen { pendingOpenChans := r.server.fundingMgr.PendingChannels() for _, pendingOpen := range pendingOpenChans { // TODO(roasbeef): add confirmation progress pendingChan := &lnrpc.PendingChannelResponse_PendingChannel{ PeerId: pendingOpen.peerId, LightningId: hex.EncodeToString(pendingOpen.lightningID[:]), ChannelPoint: pendingOpen.channelPoint.String(), Capacity: int64(pendingOpen.capacity), LocalBalance: int64(pendingOpen.localBalance), RemoteBalance: int64(pendingOpen.remoteBalance), Status: lnrpc.ChannelStatus_OPENING, } pendingChannels = append(pendingChannels, pendingChan) } } if includeClose { } return &lnrpc.PendingChannelResponse{ PendingChannels: pendingChannels, }, nil } // ListChannels returns a description of all direct active, open channels the // node knows of. // TODO(roasbeef): read all active channels from the DB? // * add 'online' toggle bit func (r *rpcServer) ListChannels(ctx context.Context, in *lnrpc.ListChannelsRequest) (*lnrpc.ListChannelsResponse, error) { resp := &lnrpc.ListChannelsResponse{} peers := r.server.Peers() for _, peer := range peers { lnID := hex.EncodeToString(peer.identityPub.SerializeCompressed()) chanSnapshots := peer.ChannelSnapshots() for _, chanSnapshot := range chanSnapshots { channel := &lnrpc.ActiveChannel{ RemotePubkey: lnID, ChannelPoint: chanSnapshot.ChannelPoint.String(), Capacity: int64(chanSnapshot.Capacity), LocalBalance: int64(chanSnapshot.LocalBalance), RemoteBalance: int64(chanSnapshot.RemoteBalance), NumUpdates: chanSnapshot.NumUpdates, PendingHtlcs: make([]*lnrpc.HTLC, len(chanSnapshot.Htlcs)), } for i, htlc := range chanSnapshot.Htlcs { channel.PendingHtlcs[i] = &lnrpc.HTLC{ Incoming: htlc.Incoming, Amount: int64(htlc.Amt), HashLock: htlc.RHash[:], ExpirationHeight: htlc.RefundTimeout, RevocationDelay: htlc.RevocationDelay, } } resp.Channels = append(resp.Channels, channel) } } return resp, nil } // SendPayment dispatches a bi-directional streaming RPC for sending payments // through the Lightning Network. A single RPC invocation creates a persistent // bi-directional stream allowing clients to rapidly send payments through the // Lightning Network with a single persistent connection. func (r *rpcServer) SendPayment(paymentStream lnrpc.Lightning_SendPaymentServer) error { queryTimeout := time.Duration(time.Minute) errChan := make(chan error, 1) for { select { case err := <-errChan: return err default: // Receive the next pending payment within the stream sent by // the client. If we read the EOF sentinel, then the client has // closed the stream, and we can exit normally. nextPayment, err := paymentStream.Recv() if err == io.EOF { return nil } else if err != nil { return err } // Query the routing table for a potential path to the // destination node. If a path is ultimately // unavailable, then an error will be returned. destNode := hex.EncodeToString(nextPayment.Dest) targetVertex := graph.NewID(destNode) path, err := r.server.routingMgr.FindPath(targetVertex, queryTimeout) if err != nil { return err } rpcsLog.Tracef("[sendpayment] selected route: %v", path) // Generate the raw encoded sphinx packet to be // included along with the HTLC add message. // We snip off the first hop from the path as within // the routing table's star graph, we're always the // first hop. sphinxPacket, err := generateSphinxPacket(path[1:]) if err != nil { return err } // If we're in debug HTLC mode, then all outgoing // HTLC's will pay to the same debug rHash. Otherwise, // we pay to the rHash specified within the RPC // request. var rHash [32]byte if cfg.DebugHTLC { rHash = debugHash } else { copy(rHash[:], nextPayment.PaymentHash) } // Craft an HTLC packet to send to the routing // sub-system. The meta-data within this packet will be // used to route the payment through the network. htlcAdd := &lnwire.HTLCAddRequest{ Amount: lnwire.CreditsAmount(nextPayment.Amt), RedemptionHashes: [][32]byte{rHash}, OnionBlob: sphinxPacket, } firstHopPub, err := hex.DecodeString(path[1].String()) if err != nil { return err } destAddr := wire.ShaHash(fastsha256.Sum256(firstHopPub)) htlcPkt := &htlcPacket{ dest: destAddr, msg: htlcAdd, } // TODO(roasbeef): semaphore to limit num outstanding // goroutines. go func() { // Finally, send this next packet to the routing layer in order // to complete the next payment. // TODO(roasbeef): this should go through the L3 router once // multi-hop is in place. if err := r.server.htlcSwitch.SendHTLC(htlcPkt); err != nil { errChan <- err return } // TODO(roasbeef): proper responses resp := &lnrpc.SendResponse{} if err := paymentStream.Send(resp); err != nil { errChan <- err return } }() } } return nil } // generateSphinxPacket generates then encodes a sphinx packet which encodes // the onion route specified by the passed list of graph vertexes. The blob // returned from this function can immediately be included within an HTLC add // packet to be sent to the first hop within the route. func generateSphinxPacket(vertexes []graph.ID) ([]byte, error) { var dest sphinx.LightningAddress e2eMessage := []byte("test") route := make([]*btcec.PublicKey, len(vertexes)) for i, vertex := range vertexes { vertexBytes, err := hex.DecodeString(vertex.String()) if err != nil { return nil, err } pub, err := btcec.ParsePubKey(vertexBytes, btcec.S256()) if err != nil { return nil, err } route[i] = pub } // Next generate the onion routing packet which allows // us to perform privacy preserving source routing // across the network. var onionBlob bytes.Buffer sphinxPacket, err := sphinx.NewOnionPacket(route, dest, e2eMessage) if err != nil { return nil, err } if err := sphinxPacket.Encode(&onionBlob); err != nil { return nil, err } rpcsLog.Tracef("[sendpayment] generated sphinx packet: %v", newLogClosure(func() string { // We unset the internal curve here in order to keep // the logs from getting noisy. sphinxPacket.Header.EphemeralKey.Curve = nil return spew.Sdump(sphinxPacket) })) return onionBlob.Bytes(), nil } // AddInvoice attempts to add a new invoice to the invoice database. Any // duplicated invoices are rejected, therefore all invoices *must* have a // unique payment preimage. func (r *rpcServer) AddInvoice(ctx context.Context, invoice *lnrpc.Invoice) (*lnrpc.AddInvoiceResponse, error) { preImage := invoice.RPreimage preimageLength := len(preImage) if preimageLength != 32 { return nil, fmt.Errorf("payment preimage must be exactly "+ "32 bytes, is instead %v", preimageLength) } if len(invoice.Memo) > channeldb.MaxMemoSize { return nil, fmt.Errorf("memo too large: %v bytes "+ "(maxsize=%v)", len(invoice.Memo), channeldb.MaxMemoSize) } if len(invoice.Receipt) > channeldb.MaxReceiptSize { return nil, fmt.Errorf("receipt too large: %v bytes "+ "(maxsize=%v)", len(invoice.Receipt), channeldb.MaxReceiptSize) } i := &channeldb.Invoice{ CreationDate: time.Now(), Memo: []byte(invoice.Memo), Receipt: invoice.Receipt, Terms: channeldb.ContractTerm{ Value: btcutil.Amount(invoice.Value), }, } copy(i.Terms.PaymentPreimage[:], preImage) rpcsLog.Tracef("[addinvoice] adding new invoice %v", newLogClosure(func() string { return spew.Sdump(i) })) if err := r.server.invoices.AddInvoice(i); err != nil { return nil, err } rHash := fastsha256.Sum256(preImage) return &lnrpc.AddInvoiceResponse{ RHash: rHash[:], }, nil } // LookupInvoice attemps to look up an invoice according to its payment hash. // The passed payment hash *must* be exactly 32 bytes, if not an error is // returned. func (r *rpcServer) LookupInvoice(ctx context.Context, req *lnrpc.PaymentHash) (*lnrpc.Invoice, error) { if len(req.RHash) != 32 { return nil, fmt.Errorf("payment hash must be exactly "+ "32 bytes, is instead %v", len(req.RHash)) } var payHash [32]byte copy(payHash[:], req.RHash) rpcsLog.Tracef("[lookupinvoice] searching for invoice %x", payHash[:]) invoice, err := r.server.invoices.LookupInvoice(payHash) if err != nil { return nil, err } rpcsLog.Tracef("[lookupinvoice] located invoice %v", newLogClosure(func() string { return spew.Sdump(invoice) })) return &lnrpc.Invoice{ Memo: string(invoice.Memo[:]), Receipt: invoice.Receipt[:], RPreimage: invoice.Terms.PaymentPreimage[:], Value: int64(invoice.Terms.Value), Settled: invoice.Terms.Settled, }, nil } // ListInvoices returns a list of all the invoices currently stored within the // database. Any active debug invoices are ignored. func (r *rpcServer) ListInvoices(ctx context.Context, req *lnrpc.ListInvoiceRequest) (*lnrpc.ListInvoiceResponse, error) { dbInvoices, err := r.server.chanDB.FetchAllInvoices(req.PendingOnly) if err != nil { return nil, err } invoices := make([]*lnrpc.Invoice, len(dbInvoices)) for i, dbInvoice := range dbInvoices { invoice := &lnrpc.Invoice{ Memo: string(dbInvoice.Memo[:]), Receipt: dbInvoice.Receipt[:], RPreimage: dbInvoice.Terms.PaymentPreimage[:], Value: int64(dbInvoice.Terms.Value), Settled: dbInvoice.Terms.Settled, } invoices[i] = invoice } return &lnrpc.ListInvoiceResponse{ Invoices: invoices, }, nil } func (r *rpcServer) ShowRoutingTable(ctx context.Context, in *lnrpc.ShowRoutingTableRequest) (*lnrpc.ShowRoutingTableResponse, error) { rpcsLog.Debugf("[ShowRoutingTable]") rtCopy := r.server.routingMgr.GetRTCopy() channels := make([]*lnrpc.RoutingTableLink, 0) for _, channel := range rtCopy.AllChannels() { channels = append(channels, &lnrpc.RoutingTableLink{ Id1: channel.Id1.String(), Id2: channel.Id2.String(), Outpoint: channel.EdgeID.String(), Capacity: channel.Info.Capacity(), Weight: channel.Info.Weight(), }, ) } return &lnrpc.ShowRoutingTableResponse{ Channels: channels, }, nil }