package main import ( "bytes" "crypto/rand" "encoding/hex" "fmt" "io" "math" "net" "time" "sync" "sync/atomic" "github.com/btcsuite/fastsha256" "github.com/davecgh/go-spew/spew" "github.com/lightningnetwork/lightning-onion" "github.com/lightningnetwork/lnd/channeldb" "github.com/lightningnetwork/lnd/lnrpc" "github.com/lightningnetwork/lnd/lnwallet" "github.com/lightningnetwork/lnd/lnwire" "github.com/lightningnetwork/lnd/routing" "github.com/lightningnetwork/lnd/zpay32" "github.com/roasbeef/btcd/btcec" "github.com/roasbeef/btcd/chaincfg" "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 } // NewWitnessAddress returns a new native witness address under the control of // the local wallet. func (r *rpcServer) NewWitnessAddress(ctx context.Context, in *lnrpc.NewWitnessAddressRequest) (*lnrpc.NewAddressResponse, error) { addr, err := r.server.lnwallet.NewAddress(lnwallet.WitnessPubKey, 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. // TODO(roasbeef): also return pubkey and/or identity hash? 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") } pubkeyHex, err := hex.DecodeString(in.Addr.Pubkey) if err != nil { return nil, err } pubkey, err := btcec.ParsePubKey(pubkeyHex, btcec.S256()) if err != nil { return nil, err } host, err := net.ResolveTCPAddr("tcp", in.Addr.Host) if err != nil { return nil, err } peerAddr := &lnwire.NetAddress{ IdentityKey: pubkey, Address: host, ChainNet: activeNetParams.Net, } peerID, err := r.server.ConnectToPeer(peerAddr) if err != nil { rpcsLog.Errorf("(connectpeer): error connecting to peer: %v", err) return nil, err } // TODO(roasbeef): add pubkey return 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) // TODO(roasbeef): make it optional nodepubKey, err := btcec.ParsePubKey(in.NodePubkey, btcec.S256()) if err != nil { return err } // Instruct the server to trigger the necessary events to attempt to // open a new channel. A stream is returned in place, this stream will // be used to consume updates of the state of the pending channel. updateChan, errChan := r.server.OpenChannel(in.TargetPeerId, nodepubKey, localFundingAmt, remoteFundingAmt, in.NumConfs) var outpoint wire.OutPoint out: for { select { case err := <-errChan: rpcsLog.Errorf("unable to open channel to "+ "identityPub(%x) nor peerID(%v): %v", nodepubKey, 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 } // OpenChannelSync is a synchronous version of the OpenChannel RPC call. This // call is meant to be consumed by clients to the REST proxy. As with all other // sync calls, all byte slices are instead to be populated as hex encoded // strings. func (r *rpcServer) OpenChannelSync(ctx context.Context, in *lnrpc.OpenChannelRequest) (*lnrpc.ChannelPoint, error) { rpcsLog.Tracef("[openchannel] request to peerid(%v) "+ "allocation(us=%v, them=%v) numconfs=%v", in.TargetPeerId, in.LocalFundingAmount, in.RemoteFundingAmount, in.NumConfs) // Decode the provided target node's public key, parsing it into a pub // key object. For all sync call, byte slices are expected to be // encoded as hex strings. keyBytes, err := hex.DecodeString(in.NodePubkeyString) if err != nil { return nil, err } nodepubKey, err := btcec.ParsePubKey(keyBytes, btcec.S256()) if err != nil { return nil, err } localFundingAmt := btcutil.Amount(in.LocalFundingAmount) remoteFundingAmt := btcutil.Amount(in.RemoteFundingAmount) updateChan, errChan := r.server.OpenChannel(in.TargetPeerId, nodepubKey, localFundingAmt, remoteFundingAmt, in.NumConfs) select { // If an error occurs them immediately return the error to the client. case err := <-errChan: rpcsLog.Errorf("unable to open channel to "+ "identityPub(%x) nor peerID(%v): %v", nodepubKey, in.TargetPeerId, err) return nil, err // Otherwise, wait for the first channel update. The first update sent // is when the funding transaction is broadcast to the network. case fundingUpdate := <-updateChan: rpcsLog.Tracef("[openchannel] sending update: %v", fundingUpdate) // Parse out the txid of the pending funding transaction. The // sync client can use this to poll against the list of // PendingChannels. openUpdate := fundingUpdate.Update.(*lnrpc.OpenStatusUpdate_ChanPending) chanUpdate := openUpdate.ChanPending return &lnrpc.ChannelPoint{ FundingTxid: chanUpdate.Txid, }, nil case <-r.quit: return nil, 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) var closeType LinkCloseType switch force { case true: // TODO(roasbeef): should be able to force close w/o connection // to peer closeType = CloseForce case false: closeType = CloseRegular } updateChan, errChan := r.server.htlcSwitch.CloseLink(targetChannelPoint, closeType) 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() bestHash, bestHeight, err := r.server.bio.GetBestBlock() if err != nil { return nil, err } isSynced, err := r.server.lnwallet.IsSynced() if err != nil { return nil, err } return &lnrpc.GetInfoResponse{ IdentityPubkey: hex.EncodeToString(idPub), NumPendingChannels: pendingChannels, NumActiveChannels: activeChannels, NumPeers: uint32(len(serverPeers)), BlockHeight: uint32(bestHeight), BlockHash: bestHash.String(), SyncedToChain: isSynced, Testnet: activeNetParams.Params == &chaincfg.TestNet3Params, }, 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 nodePub := serverPeer.addr.IdentityKey.SerializeCompressed() peer := &lnrpc.Peer{ PubKey: hex.EncodeToString(nodePub), 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) { channels, err := r.server.chanDB.FetchAllChannels() if err != nil { return nil, err } var balance btcutil.Amount for _, channel := range channels { balance += channel.OurBalance } 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 pub := pendingOpen.identityPub.SerializeCompressed() pendingChan := &lnrpc.PendingChannelResponse_PendingChannel{ PeerId: pendingOpen.peerId, IdentityKey: hex.EncodeToString(pub), 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): add 'online' bit to response func (r *rpcServer) ListChannels(ctx context.Context, in *lnrpc.ListChannelsRequest) (*lnrpc.ListChannelsResponse, error) { resp := &lnrpc.ListChannelsResponse{} graph := r.server.chanDB.ChannelGraph() dbChannels, err := r.server.chanDB.FetchAllChannels() if err != nil { return nil, err } rpcsLog.Infof("[listchannels] fetched %v channels from DB", len(dbChannels)) for _, dbChannel := range dbChannels { nodePub := dbChannel.IdentityPub.SerializeCompressed() nodeID := hex.EncodeToString(nodePub) chanPoint := dbChannel.ChanID // With the channel point known, retrieve the network channel // ID from the database. chanID, err := graph.ChannelID(chanPoint) if err != nil { return nil, err } channel := &lnrpc.ActiveChannel{ RemotePubkey: nodeID, ChannelPoint: chanPoint.String(), ChanId: chanID, Capacity: int64(dbChannel.Capacity), LocalBalance: int64(dbChannel.OurBalance), RemoteBalance: int64(dbChannel.TheirBalance), TotalSatoshisSent: int64(dbChannel.TotalSatoshisSent), TotalSatoshisReceived: int64(dbChannel.TotalSatoshisReceived), NumUpdates: dbChannel.NumUpdates, PendingHtlcs: make([]*lnrpc.HTLC, len(dbChannel.Htlcs)), } for i, htlc := range dbChannel.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 } // savePayment saves a successfully completed payment to the database for // historical record keeping. func (r *rpcServer) savePayment(route *routing.Route, amount btcutil.Amount, rHash []byte) error { paymentPath := make([][33]byte, len(route.Hops)) for i, hop := range route.Hops { hopPub := hop.Channel.Node.PubKey.SerializeCompressed() copy(paymentPath[i][:], hopPub) } payment := &channeldb.OutgoingPayment{ Invoice: channeldb.Invoice{ Terms: channeldb.ContractTerm{ Value: btcutil.Amount(amount), }, CreationDate: time.Now(), }, Path: paymentPath, Fee: route.TotalFees, TimeLockLength: route.TotalTimeLock, } copy(payment.PaymentHash[:], rHash) return r.server.chanDB.AddPayment(payment) } // 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 { errChan := make(chan error, 1) payChan := make(chan *lnrpc.SendRequest) // Launch a new goroutine to handle reading new payment requests from // the client. This way we can handle errors independently of blocking // and waiting for the next payment request to come through. go func() { for { select { case <-r.quit: errChan <- nil return 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 { errChan <- nil return } else if err != nil { errChan <- err return } // If the payment request field isn't blank, // then the details of the invoice are encoded // entirely within the encode payReq. So we'll // attempt to decode it, populating the // nextPayment accordingly. if nextPayment.PaymentRequest != "" { payReq, err := zpay32.Decode(nextPayment.PaymentRequest) if err != nil { errChan <- err return } // TODO(roasbeef): eliminate necessary // encode/decode nextPayment.Dest = payReq.Destination.SerializeCompressed() nextPayment.Amt = int64(payReq.Amount) nextPayment.PaymentHash = payReq.PaymentHash[:] } payChan <- nextPayment } } }() for { select { case err := <-errChan: return err case nextPayment := <-payChan: // Parse the details of the payment which include the // pubkey of the destination and the payment amount. dest := nextPayment.Dest amt := btcutil.Amount(nextPayment.Amt) destNode, err := btcec.ParsePubKey(dest, btcec.S256()) 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 && len(nextPayment.PaymentHash) == 0 { rHash = debugHash } else { copy(rHash[:], nextPayment.PaymentHash) } // Construct and HTLC packet which a payment route (if // one is found) to the destination using a Sphinx // onion packet to encode the route. htlcPkt, route, err := r.constructPaymentRoute(destNode, amt, rHash) if err != nil { return err } // We launch a new goroutine to execute the current // payment so we can continue to serve requests while // this payment is being dispatched. // // 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. if err := r.server.htlcSwitch.SendHTLC(htlcPkt); err != nil { errChan <- err return } // Save the completed payment to the database // for record keeping purposes. if err := r.savePayment(route, amt, rHash[:]); err != nil { errChan <- err return } // TODO(roasbeef): proper responses resp := &lnrpc.SendResponse{} if err := paymentStream.Send(resp); err != nil { errChan <- err return } }() } } return nil } // SendPaymentSync is the synchronous non-streaming version of SendPayment. // This RPC is intended to be consumed by clients of the REST proxy. // Additionally, this RPC expects the destination's public key and the payment // hash (if any) to be encoded as hex strings. func (r *rpcServer) SendPaymentSync(ctx context.Context, nextPayment *lnrpc.SendRequest) (*lnrpc.SendResponse, error) { var ( destPub *btcec.PublicKey amt btcutil.Amount rHash [32]byte ) // If the proto request has an encoded payment request, then we we'll // use that solely to dipatch the payment. if nextPayment.PaymentRequest != "" { payReq, err := zpay32.Decode(nextPayment.PaymentRequest) if err != nil { return nil, err } destPub = payReq.Destination amt = payReq.Amount rHash = payReq.PaymentHash // Otherwise, the payment conditions have been manually specified in // the proto. } else { // 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. if cfg.DebugHTLC && nextPayment.PaymentHashString == "" { rHash = debugHash } else { paymentHash, err := hex.DecodeString(nextPayment.PaymentHashString) if err != nil { return nil, err } copy(rHash[:], paymentHash) } pubBytes, err := hex.DecodeString(nextPayment.DestString) if err != nil { return nil, err } destPub, err = btcec.ParsePubKey(pubBytes, btcec.S256()) if err != nil { return nil, err } amt = btcutil.Amount(nextPayment.Amt) } // Construct and HTLC packet which a payment route (if // one is found) to the destination using a Sphinx // onoin packet to encode the route. htlcPkt, route, err := r.constructPaymentRoute(destPub, amt, rHash) if err != nil { return nil, err } // Next, send this next packet to the routing layer in order to // complete the next payment. if err := r.server.htlcSwitch.SendHTLC(htlcPkt); err != nil { return nil, err } // With the payment completed successfully, we now ave the details of // the completed payment to the databse for historical record keeping. if err := r.savePayment(route, amt, rHash[:]); err != nil { return nil, err } return &lnrpc.SendResponse{}, nil } // constructPaymentRoute attempts to construct a complete HTLC packet which // encapsulates a Sphinx onion packet that encodes the end-to-end route any // payment instructions necessary to complete an HTLC. If a route is unable to // be located, then an error is returned indicating as much. func (r *rpcServer) constructPaymentRoute(destNode *btcec.PublicKey, amt btcutil.Amount, rHash [32]byte) (*htlcPacket, *routing.Route, error) { const queryTimeout = time.Duration(time.Second * 10) // Query the channel router for a potential path to the destination // node that can support our payment amount. If a path is ultimately // unavailable, then an error will be returned. route, err := r.server.chanRouter.FindRoute(destNode, amt) if err != nil { return nil, nil, err } rpcsLog.Tracef("[sendpayment] selected route: %#v", route) // 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(route, rHash[:]) if err != nil { return nil, nil, err } // 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: route.TotalAmount, RedemptionHashes: [][32]byte{rHash}, OnionBlob: sphinxPacket, } firstHopPub := route.Hops[0].Channel.Node.PubKey.SerializeCompressed() destInterface := wire.ShaHash(fastsha256.Sum256(firstHopPub)) return &htlcPacket{ dest: destInterface, msg: htlcAdd, }, route, nil } // generateSphinxPacket generates then encodes a sphinx packet which encodes // the onion route specified by the passed layer 3 route. 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(route *routing.Route, paymentHash []byte) ([]byte, error) { // First obtain all the public keys along the route which are contained // in each hop. nodes := make([]*btcec.PublicKey, len(route.Hops)) for i, hop := range route.Hops { // We create a new instance of the public key to avoid possibly // mutating the curve parameters, which are unset in a higher // level in order to avoid spamming the logs. pub := btcec.PublicKey{ btcec.S256(), hop.Channel.Node.PubKey.X, hop.Channel.Node.PubKey.Y, } nodes[i] = &pub } // Next we generate the per-hop payload which gives each node within // the route the necessary information (fees, CLTV value, etc) to // properly forward the payment. // TODO(roasbeef): properly set CLTV value, payment amount, and chain // within hop paylods. var hopPayloads [][]byte for i := 0; i < len(route.Hops); i++ { payload := bytes.Repeat([]byte{byte('A' + i)}, sphinx.HopPayloadSize) hopPayloads = append(hopPayloads, payload) } sessionKey, err := btcec.NewPrivateKey(btcec.S256()) if err != nil { return nil, err } // Next generate the onion routing packet which allows // us to perform privacy preserving source routing // across the network. sphinxPacket, err := sphinx.NewOnionPacket(nodes, sessionKey, hopPayloads, paymentHash) if err != nil { return nil, err } // Finally, encode Sphinx packet using it's wire representation to be // included within the HTLC add packet. var onionBlob bytes.Buffer 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) { var paymentPreimage [32]byte switch { // If a preimage wasn't specified, then we'll generate a new preimage // from fresh cryptographic randomness. case len(invoice.RPreimage) == 0: if _, err := rand.Read(paymentPreimage[:]); err != nil { return nil, err } // Otherwise, if a preimage was specified, then it MUST be exactly // 32-bytes. case len(invoice.RPreimage) > 0 && len(invoice.RPreimage) != 32: return nil, fmt.Errorf("payment preimage must be exactly "+ "32 bytes, is instead %v", len(invoice.RPreimage)) // If the preimage meets the size specifications, then it can be used // as is. default: copy(paymentPreimage[:], invoice.RPreimage[:]) } // The size of the memo and receipt attached must not exceed the // maximum values for either of the fields. 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) } // Finally, the value of an invoice MUST NOT be zero. if invoice.Value == 0 { return nil, fmt.Errorf("zero value invoices are disallowed") } 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[:], paymentPreimage[:]) rpcsLog.Tracef("[addinvoice] adding new invoice %v", newLogClosure(func() string { return spew.Sdump(i) })) // With all sanity checks passed, write the invoice to the database. if err := r.server.invoices.AddInvoice(i); err != nil { return nil, err } // Next, generate the payment hash itself from the pre-image. This will // be used by clients to query for the state of a particular invoice. rHash := fastsha256.Sum256(paymentPreimage[:]) // Finally we also create an encoded payment request which allows the // caller to comactly send the invoice to the payer. payReqString := zpay32.Encode(&zpay32.PaymentRequest{ Destination: r.server.identityPriv.PubKey(), PaymentHash: rHash, Amount: btcutil.Amount(invoice.Value), }) return &lnrpc.AddInvoiceResponse{ RHash: rHash[:], PaymentRequest: payReqString, }, 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) { var ( payHash [32]byte rHash []byte err error ) // If the RHash as a raw string was provided, then decode that and use // that directly. Otherwise, we use the raw bytes provided. if req.RHashStr != "" { rHash, err = hex.DecodeString(req.RHashStr) if err != nil { return nil, err } } else { rHash = req.RHash } // Ensure that the payment hash is *exactly* 32-bytes. if len(rHash) != 0 && len(rHash) != 32 { return nil, fmt.Errorf("payment hash must be exactly "+ "32 bytes, is instead %v", len(rHash)) } copy(payHash[:], 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, CreationDate: dbInvoice.CreationDate.Unix(), } invoices[i] = invoice } return &lnrpc.ListInvoiceResponse{ Invoices: invoices, }, nil } // SubscribeInvoices returns a uni-directional stream (sever -> client) for // notifying the client of newly added/settled invoices. func (r *rpcServer) SubscribeInvoices(req *lnrpc.InvoiceSubscription, updateStream lnrpc.Lightning_SubscribeInvoicesServer) error { invoiceClient := r.server.invoices.SubscribeNotifications() defer invoiceClient.Cancel() for { select { // TODO(roasbeef): include newly added invoices? case settledInvoice := <-invoiceClient.SettledInvoices: invoice := &lnrpc.Invoice{ Memo: string(settledInvoice.Memo[:]), Receipt: settledInvoice.Receipt[:], RPreimage: settledInvoice.Terms.PaymentPreimage[:], Value: int64(settledInvoice.Terms.Value), Settled: settledInvoice.Terms.Settled, } if err := updateStream.Send(invoice); err != nil { return err } case <-r.quit: return nil } } return nil } // SubscribeTransactions creates a uni-directional stream (server -> client) in // which any newly discovered transactions relevant to the wallet are sent // over. func (r *rpcServer) SubscribeTransactions(req *lnrpc.GetTransactionsRequest, updateStream lnrpc.Lightning_SubscribeTransactionsServer) error { txClient, err := r.server.lnwallet.SubscribeTransactions() if err != nil { return err } defer txClient.Cancel() for { select { case tx := <-txClient.ConfirmedTransactions(): detail := &lnrpc.Transaction{ TxHash: tx.Hash.String(), Amount: tx.Value.ToBTC(), NumConfirmations: tx.NumConfirmations, BlockHash: tx.BlockHash.String(), TimeStamp: tx.Timestamp, TotalFees: tx.TotalFees, } if err := updateStream.Send(detail); err != nil { return err } case tx := <-txClient.UnconfirmedTransactions(): detail := &lnrpc.Transaction{ TxHash: tx.Hash.String(), Amount: tx.Value.ToBTC(), TimeStamp: tx.Timestamp, TotalFees: tx.TotalFees, } if err := updateStream.Send(detail); err != nil { return err } case <-r.quit: return nil } } return nil } // GetTransactions returns a list of describing all the known transactions // relevant to the wallet. func (r *rpcServer) GetTransactions(context.Context, *lnrpc.GetTransactionsRequest) (*lnrpc.TransactionDetails, error) { // TODO(roasbeef): add pagination support transactions, err := r.server.lnwallet.ListTransactionDetails() if err != nil { return nil, err } txDetails := &lnrpc.TransactionDetails{ Transactions: make([]*lnrpc.Transaction, len(transactions)), } for i, tx := range transactions { txDetails.Transactions[i] = &lnrpc.Transaction{ TxHash: tx.Hash.String(), Amount: tx.Value.ToBTC(), NumConfirmations: tx.NumConfirmations, BlockHash: tx.BlockHash.String(), TimeStamp: tx.Timestamp, TotalFees: tx.TotalFees, } } return txDetails, nil } // DescribeGraph returns a description of the latest graph state from the PoV // of the node. The graph information is partitioned into two components: all // the nodes/vertexes, and all the edges that connect the vertexes themselves. // As this is a directed graph, the edges also contain the node directional // specific routing policy which includes: the time lock delta, fee // information, etc. func (r *rpcServer) DescribeGraph(context.Context, *lnrpc.ChannelGraphRequest) (*lnrpc.ChannelGraph, error) { resp := &lnrpc.ChannelGraph{} // Obtain the pinter to the global singleton channel graph, this will // provide a consistent view of the graph due to bolt db's // transactional model. graph := r.server.chanDB.ChannelGraph() // First iterate through all the known nodes (connected or unconnected // within the graph), collating their current state into the RPC // response. err := graph.ForEachNode(func(node *channeldb.LightningNode) error { resp.Nodes = append(resp.Nodes, &lnrpc.LightningNode{ LastUpdate: uint32(node.LastUpdate.Unix()), PubKey: hex.EncodeToString(node.PubKey.SerializeCompressed()), Address: node.Address.String(), Alias: node.Alias, }) return nil }) if err != nil { return nil, err } // Next, for each active channel we know of within the graph, create a // similar response which details both the edge information as well as // the routing policies of th nodes connecting the two edges. err = graph.ForEachChannel(func(c1, c2 *channeldb.ChannelEdge) error { edge := marshalDbEdge(c1, c2) resp.Edges = append(resp.Edges, edge) return nil }) if err != nil && err != channeldb.ErrGraphNoEdgesFound { return nil, err } return resp, nil } func marshalDbEdge(c1, c2 *channeldb.ChannelEdge) *lnrpc.ChannelEdge { node1Pub := c2.Node.PubKey.SerializeCompressed() node2Pub := c1.Node.PubKey.SerializeCompressed() edge := &lnrpc.ChannelEdge{ ChannelId: c1.ChannelID, ChanPoint: c1.ChannelPoint.String(), LastUpdate: uint32(c1.LastUpdate.Unix()), Node1Pub: hex.EncodeToString(node1Pub), Node2Pub: hex.EncodeToString(node2Pub), Capacity: int64(c1.Capacity), } edge.Node1Policy = &lnrpc.RoutingPolicy{ TimeLockDelta: uint32(c1.Expiry), MinHtlc: int64(c1.MinHTLC), FeeBaseMsat: int64(c1.FeeBaseMSat), FeeRateMilliMsat: int64(c1.FeeProportionalMillionths), } edge.Node2Policy = &lnrpc.RoutingPolicy{ TimeLockDelta: uint32(c2.Expiry), MinHtlc: int64(c2.MinHTLC), FeeBaseMsat: int64(c2.FeeBaseMSat), FeeRateMilliMsat: int64(c2.FeeProportionalMillionths), } return edge } // GetChainInfo returns the latest authenticated network announcement for the // given channel identified by its channel ID: an 8-byte integer which uniquely // identifies the location of transaction's funding output within the block // chain. func (r *rpcServer) GetChanInfo(_ context.Context, in *lnrpc.ChanInfoRequest) (*lnrpc.ChannelEdge, error) { graph := r.server.chanDB.ChannelGraph() edge1, edge2, err := graph.FetchChannelEdgesByID(in.ChanId) if err != nil { return nil, err } // Convert the database's edge format into the network/RPC edge format // which couples the edge itself along with the directional node // routing policies of each node involved within the channel. channelEdge := marshalDbEdge(edge1, edge2) return channelEdge, nil } // GetNodeInfo returns the latest advertised and aggregate authenticated // channel information for the specified node identified by its public key. func (r *rpcServer) GetNodeInfo(_ context.Context, in *lnrpc.NodeInfoRequest) (*lnrpc.NodeInfo, error) { graph := r.server.chanDB.ChannelGraph() // First, parse the hex-encoded public key into a full in-memory public // key object we can work with for querying. pubKeyBytes, err := hex.DecodeString(in.PubKey) if err != nil { return nil, err } pubKey, err := btcec.ParsePubKey(pubKeyBytes, btcec.S256()) if err != nil { return nil, err } // With the public key decoded, attempt to fetch the node corresponding // to this public key. If the node cannot be found, then an error will // be returned. node, err := graph.FetchLightningNode(pubKey) if err != nil { return nil, err } // With the node obtained, we'll now iterate through all its out going // edges to gather some basic statistics about its out going channels. var ( numChannels uint32 totalCapcity btcutil.Amount ) if err := node.ForEachChannel(nil, func(edge *channeldb.ChannelEdge) error { numChannels++ totalCapcity += edge.Capacity return nil }); err != nil { return nil, err } return &lnrpc.NodeInfo{ Node: &lnrpc.LightningNode{ LastUpdate: uint32(node.LastUpdate.Unix()), PubKey: in.PubKey, Address: node.Address.String(), Alias: node.Alias, }, NumChannels: numChannels, TotalCapacity: int64(totalCapcity), }, nil } // QueryRoute attempts to query the daemons' Channel Router for a possible // route to a target destination capable of carrying a specific amount of // satoshis within the route's flow. The retuned route contains the full // details required to craft and send an HTLC, also including the necessary // information that should be present within the Sphinx packet encapsualted // within the HTLC. // // TODO(roasbeef): should return a slice of routes in reality // * create separate PR to send based on well formatted route func (r *rpcServer) QueryRoute(_ context.Context, in *lnrpc.RouteRequest) (*lnrpc.Route, error) { // First parse the hex-encdoed public key into a full public key objet // we can properly manipulate. pubKeyBytes, err := hex.DecodeString(in.PubKey) if err != nil { return nil, err } pubKey, err := btcec.ParsePubKey(pubKeyBytes, btcec.S256()) if err != nil { return nil, err } // Query the channel router for a possible path to the destination that // can carry `in.Amt` satoshis _including_ the total fee required on // the route. route, err := r.server.chanRouter.FindRoute(pubKey, btcutil.Amount(in.Amt)) if err != nil { return nil, err } // If a route exsits within the network that is able to support our // request, then we'll convert the result into the format required by // the RPC system. resp := &lnrpc.Route{ TotalTimeLock: route.TotalTimeLock, TotalFees: int64(route.TotalFees), TotalAmt: int64(route.TotalAmount), Hops: make([]*lnrpc.Hop, len(route.Hops)), } for i, hop := range route.Hops { resp.Hops[i] = &lnrpc.Hop{ ChanId: hop.Channel.ChannelID, ChanCapacity: int64(hop.Channel.Capacity), AmtToForward: int64(hop.AmtToForward), Fee: int64(hop.Fee), } } return resp, nil } // GetNetworkInfo returns some basic stats about the known channel graph from // the PoV of the node. func (r *rpcServer) GetNetworkInfo(context.Context, *lnrpc.NetworkInfoRequest) (*lnrpc.NetworkInfo, error) { graph := r.server.chanDB.ChannelGraph() var ( numNodes uint32 numChannels uint32 maxChanOut uint32 totalNetworkCapacity btcutil.Amount minChannelSize btcutil.Amount = math.MaxInt64 maxChannelSize btcutil.Amount ) // TODO(roasbeef): ideally all below is completed in a single // transaction // First run through all the known nodes in the within our view of the // network, tallying up the total number of nodes, and also gathering // each node so we can measure the graph diamter and degree stats // below. var nodes []*channeldb.LightningNode if err := graph.ForEachNode(func(node *channeldb.LightningNode) error { numNodes++ nodes = append(nodes, node) return nil }); err != nil { return nil, err } // With all the nodes gathered, we can now perform a basic traversal to // ascertain the graph's diameter, and also the max out-degree of a // node. for _, node := range nodes { var outDegree uint32 err := node.ForEachChannel(nil, func(c *channeldb.ChannelEdge) error { outDegree++ return nil }) if err != nil { return nil, err } if outDegree > maxChanOut { outDegree = maxChanOut } } // Finally, we traverse each channel visiting both channel edges at // once to avoid double counting any stats we're attempting to gather. if err := graph.ForEachChannel(func(c1, c2 *channeldb.ChannelEdge) error { chanCapacity := c1.Capacity if chanCapacity < minChannelSize { minChannelSize = chanCapacity } if chanCapacity > maxChannelSize { maxChannelSize = chanCapacity } totalNetworkCapacity += chanCapacity numChannels++ return nil }); err != nil { return nil, err } // TODO(roasbeef): also add oldest channel? return &lnrpc.NetworkInfo{ MaxOutDegree: maxChanOut, AvgOutDegree: float64(numChannels) / float64(numNodes), NumNodes: numNodes, NumChannels: numChannels, TotalNetworkCapacity: int64(totalNetworkCapacity), AvgChannelSize: float64(totalNetworkCapacity) / float64(numChannels), MinChannelSize: int64(minChannelSize), MaxChannelSize: int64(maxChannelSize), }, nil } // ListPayments returns a list of all outgoing payments. func (r *rpcServer) ListPayments(context.Context, *lnrpc.ListPaymentsRequest) (*lnrpc.ListPaymentsResponse, error) { rpcsLog.Debugf("[ListPayments]") payments, err := r.server.chanDB.FetchAllPayments() if err != nil { return nil, err } paymentsResp := &lnrpc.ListPaymentsResponse{ Payments: make([]*lnrpc.Payment, len(payments)), } for i, payment := range payments { path := make([]string, len(payment.Path)) for i, hop := range payment.Path { path[i] = hex.EncodeToString(hop[:]) } paymentsResp.Payments[i] = &lnrpc.Payment{ PaymentHash: hex.EncodeToString(payment.PaymentHash[:]), Value: int64(payment.Terms.Value), CreationDate: payment.CreationDate.Unix(), Path: path, } } return paymentsResp, nil } // DeleteAllPayments deletes all outgoing payments from DB. func (r *rpcServer) DeleteAllPayments(context.Context, *lnrpc.DeleteAllPaymentsRequest) (*lnrpc.DeleteAllPaymentsResponse, error) { rpcsLog.Debugf("[DeleteAllPayments]") if err := r.server.chanDB.DeleteAllPayments(); err != nil { return nil, err } return &lnrpc.DeleteAllPaymentsResponse{}, nil } // SetAlias... func (r *rpcServer) SetAlias(context.Context, *lnrpc.SetAliasRequest) (*lnrpc.SetAliasResponse, error) { return nil, nil }