package chainreg import ( "encoding/hex" "errors" "fmt" "io/ioutil" "net" "os" "strconv" "strings" "sync" "time" "github.com/btcsuite/btcd/chaincfg/chainhash" "github.com/btcsuite/btcd/rpcclient" "github.com/btcsuite/btcutil" "github.com/btcsuite/btcwallet/chain" "github.com/btcsuite/btcwallet/wallet" "github.com/lightninglabs/neutrino" "github.com/lightningnetwork/lnd/chainntnfs" "github.com/lightningnetwork/lnd/chainntnfs/bitcoindnotify" "github.com/lightningnetwork/lnd/chainntnfs/btcdnotify" "github.com/lightningnetwork/lnd/chainntnfs/neutrinonotify" "github.com/lightningnetwork/lnd/channeldb" "github.com/lightningnetwork/lnd/htlcswitch" "github.com/lightningnetwork/lnd/input" "github.com/lightningnetwork/lnd/keychain" "github.com/lightningnetwork/lnd/lncfg" "github.com/lightningnetwork/lnd/lnwallet" "github.com/lightningnetwork/lnd/lnwallet/btcwallet" "github.com/lightningnetwork/lnd/lnwallet/chainfee" "github.com/lightningnetwork/lnd/lnwire" "github.com/lightningnetwork/lnd/routing/chainview" ) // Config houses necessary fields that a chainControl instance needs to // function. type Config struct { // Bitcoin defines settings for the Bitcoin chain. Bitcoin *lncfg.Chain // Litecoin defines settings for the Litecoin chain. Litecoin *lncfg.Chain // PrimaryChain is a function that returns our primary chain via its // ChainCode. PrimaryChain func() ChainCode // HeightHintCacheQueryDisable is a boolean that disables height hint // queries if true. HeightHintCacheQueryDisable bool // NeutrinoMode defines settings for connecting to a neutrino light-client. NeutrinoMode *lncfg.Neutrino // BitcoindMode defines settings for connecting to a bitcoind node. BitcoindMode *lncfg.Bitcoind // LitecoindMode defines settings for connecting to a litecoind node. LitecoindMode *lncfg.Bitcoind // BtcdMode defines settings for connecting to a btcd node. BtcdMode *lncfg.Btcd // LtcdMode defines settings for connecting to an ltcd node. LtcdMode *lncfg.Btcd // LocalChanDB is a pointer to the local backing channel database. LocalChanDB *channeldb.DB // RemoteChanDB is a pointer to the remote backing channel database. RemoteChanDB *channeldb.DB // PrivateWalletPw is the private wallet password to the underlying // btcwallet instance. PrivateWalletPw []byte // PublicWalletPw is the public wallet password to the underlying btcwallet // instance. PublicWalletPw []byte // Birthday specifies the time the wallet was initially created. Birthday time.Time // RecoveryWindow specifies the address look-ahead for which to scan when // restoring a wallet. RecoveryWindow uint32 // Wallet is a pointer to the backing wallet instance. Wallet *wallet.Wallet // NeutrinoCS is a pointer to a neutrino ChainService. Must be non-nil if // using neutrino. NeutrinoCS *neutrino.ChainService // ActiveNetParams details the current chain we are on. ActiveNetParams BitcoinNetParams // FeeURL defines the URL for fee estimation we will use. This field is // optional. FeeURL string } const ( // DefaultBitcoinMinHTLCInMSat is the default smallest value htlc this // node will accept. This value is proposed in the channel open sequence // and cannot be changed during the life of the channel. It is 1 msat by // default to allow maximum flexibility in deciding what size payments // to forward. // // All forwarded payments are subjected to the min htlc constraint of // the routing policy of the outgoing channel. This implicitly controls // the minimum htlc value on the incoming channel too. DefaultBitcoinMinHTLCInMSat = lnwire.MilliSatoshi(1) // DefaultBitcoinMinHTLCOutMSat is the default minimum htlc value that // we require for sending out htlcs. Our channel peer may have a lower // min htlc channel parameter, but we - by default - don't forward // anything under the value defined here. DefaultBitcoinMinHTLCOutMSat = lnwire.MilliSatoshi(1000) // DefaultBitcoinBaseFeeMSat is the default forwarding base fee. DefaultBitcoinBaseFeeMSat = lnwire.MilliSatoshi(1000) // DefaultBitcoinFeeRate is the default forwarding fee rate. DefaultBitcoinFeeRate = lnwire.MilliSatoshi(1) // DefaultBitcoinTimeLockDelta is the default forwarding time lock // delta. DefaultBitcoinTimeLockDelta = 40 DefaultLitecoinMinHTLCInMSat = lnwire.MilliSatoshi(1) DefaultLitecoinMinHTLCOutMSat = lnwire.MilliSatoshi(1000) DefaultLitecoinBaseFeeMSat = lnwire.MilliSatoshi(1000) DefaultLitecoinFeeRate = lnwire.MilliSatoshi(1) DefaultLitecoinTimeLockDelta = 576 DefaultLitecoinDustLimit = btcutil.Amount(54600) // DefaultBitcoinStaticFeePerKW is the fee rate of 50 sat/vbyte // expressed in sat/kw. DefaultBitcoinStaticFeePerKW = chainfee.SatPerKWeight(12500) // DefaultBitcoinStaticMinRelayFeeRate is the min relay fee used for // static estimators. DefaultBitcoinStaticMinRelayFeeRate = chainfee.FeePerKwFloor // DefaultLitecoinStaticFeePerKW is the fee rate of 200 sat/vbyte // expressed in sat/kw. DefaultLitecoinStaticFeePerKW = chainfee.SatPerKWeight(50000) // BtcToLtcConversionRate is a fixed ratio used in order to scale up // payments when running on the Litecoin chain. BtcToLtcConversionRate = 60 ) // DefaultBtcChannelConstraints is the default set of channel constraints that are // meant to be used when initially funding a Bitcoin channel. // // TODO(halseth): make configurable at startup? var DefaultBtcChannelConstraints = channeldb.ChannelConstraints{ DustLimit: lnwallet.DefaultDustLimit(), MaxAcceptedHtlcs: input.MaxHTLCNumber / 2, } // DefaultLtcChannelConstraints is the default set of channel constraints that are // meant to be used when initially funding a Litecoin channel. var DefaultLtcChannelConstraints = channeldb.ChannelConstraints{ DustLimit: DefaultLitecoinDustLimit, MaxAcceptedHtlcs: input.MaxHTLCNumber / 2, } // ChainControl couples the three primary interfaces lnd utilizes for a // particular chain together. A single ChainControl instance will exist for all // the chains lnd is currently active on. type ChainControl struct { // ChainIO represents an abstraction over a source that can query the blockchain. ChainIO lnwallet.BlockChainIO // FeeEstimator is used to estimate an optimal fee for transactions important to us. FeeEstimator chainfee.Estimator // Signer is used to provide signatures over things like transactions. Signer input.Signer // KeyRing represents a set of keys that we have the private keys to. KeyRing keychain.SecretKeyRing // Wc is an abstraction over some basic wallet commands. This base set of commands // will be provided to the Wallet *LightningWallet raw pointer below. Wc lnwallet.WalletController // MsgSigner is used to sign arbitrary messages. MsgSigner lnwallet.MessageSigner // ChainNotifier is used to receive blockchain events that we are interested in. ChainNotifier chainntnfs.ChainNotifier // ChainView is used in the router for maintaining an up-to-date graph. ChainView chainview.FilteredChainView // Wallet is our LightningWallet that also contains the abstract Wc above. This wallet // handles all of the lightning operations. Wallet *lnwallet.LightningWallet // RoutingPolicy is the routing policy we have decided to use. RoutingPolicy htlcswitch.ForwardingPolicy // MinHtlcIn is the minimum HTLC we will accept. MinHtlcIn lnwire.MilliSatoshi } // NewChainControl attempts to create a ChainControl instance according // to the parameters in the passed configuration. Currently three // branches of ChainControl instances exist: one backed by a running btcd // full-node, another backed by a running bitcoind full-node, and the other // backed by a running neutrino light client instance. When running with a // neutrino light client instance, `neutrinoCS` must be non-nil. func NewChainControl(cfg *Config) (*ChainControl, error) { // Set the RPC config from the "home" chain. Multi-chain isn't yet // active, so we'll restrict usage to a particular chain for now. homeChainConfig := cfg.Bitcoin if cfg.PrimaryChain() == LitecoinChain { homeChainConfig = cfg.Litecoin } log.Infof("Primary chain is set to: %v", cfg.PrimaryChain()) cc := &ChainControl{} switch cfg.PrimaryChain() { case BitcoinChain: cc.RoutingPolicy = htlcswitch.ForwardingPolicy{ MinHTLCOut: cfg.Bitcoin.MinHTLCOut, BaseFee: cfg.Bitcoin.BaseFee, FeeRate: cfg.Bitcoin.FeeRate, TimeLockDelta: cfg.Bitcoin.TimeLockDelta, } cc.MinHtlcIn = cfg.Bitcoin.MinHTLCIn cc.FeeEstimator = chainfee.NewStaticEstimator( DefaultBitcoinStaticFeePerKW, DefaultBitcoinStaticMinRelayFeeRate, ) case LitecoinChain: cc.RoutingPolicy = htlcswitch.ForwardingPolicy{ MinHTLCOut: cfg.Litecoin.MinHTLCOut, BaseFee: cfg.Litecoin.BaseFee, FeeRate: cfg.Litecoin.FeeRate, TimeLockDelta: cfg.Litecoin.TimeLockDelta, } cc.MinHtlcIn = cfg.Litecoin.MinHTLCIn cc.FeeEstimator = chainfee.NewStaticEstimator( DefaultLitecoinStaticFeePerKW, 0, ) default: return nil, fmt.Errorf("default routing policy for chain %v is "+ "unknown", cfg.PrimaryChain()) } walletConfig := &btcwallet.Config{ PrivatePass: cfg.PrivateWalletPw, PublicPass: cfg.PublicWalletPw, Birthday: cfg.Birthday, RecoveryWindow: cfg.RecoveryWindow, DataDir: homeChainConfig.ChainDir, NetParams: cfg.ActiveNetParams.Params, CoinType: cfg.ActiveNetParams.CoinType, Wallet: cfg.Wallet, } var err error heightHintCacheConfig := chainntnfs.CacheConfig{ QueryDisable: cfg.HeightHintCacheQueryDisable, } if cfg.HeightHintCacheQueryDisable { log.Infof("Height Hint Cache Queries disabled") } // Initialize the height hint cache within the chain directory. hintCache, err := chainntnfs.NewHeightHintCache( heightHintCacheConfig, cfg.LocalChanDB, ) if err != nil { return nil, fmt.Errorf("unable to initialize height hint "+ "cache: %v", err) } // If spv mode is active, then we'll be using a distinct set of // chainControl interfaces that interface directly with the p2p network // of the selected chain. switch homeChainConfig.Node { case "neutrino": // We'll create ChainNotifier and FilteredChainView instances, // along with the wallet's ChainSource, which are all backed by // the neutrino light client. cc.ChainNotifier = neutrinonotify.New( cfg.NeutrinoCS, hintCache, hintCache, ) cc.ChainView, err = chainview.NewCfFilteredChainView(cfg.NeutrinoCS) if err != nil { return nil, err } // Map the deprecated neutrino feeurl flag to the general fee // url. if cfg.NeutrinoMode.FeeURL != "" { if cfg.FeeURL != "" { return nil, errors.New("feeurl and " + "neutrino.feeurl are mutually exclusive") } cfg.FeeURL = cfg.NeutrinoMode.FeeURL } walletConfig.ChainSource = chain.NewNeutrinoClient( cfg.ActiveNetParams.Params, cfg.NeutrinoCS, ) case "bitcoind", "litecoind": var bitcoindMode *lncfg.Bitcoind switch { case cfg.Bitcoin.Active: bitcoindMode = cfg.BitcoindMode case cfg.Litecoin.Active: bitcoindMode = cfg.LitecoindMode } // Otherwise, we'll be speaking directly via RPC and ZMQ to a // bitcoind node. If the specified host for the btcd/ltcd RPC // server already has a port specified, then we use that // directly. Otherwise, we assume the default port according to // the selected chain parameters. var bitcoindHost string if strings.Contains(bitcoindMode.RPCHost, ":") { bitcoindHost = bitcoindMode.RPCHost } else { // The RPC ports specified in chainparams.go assume // btcd, which picks a different port so that btcwallet // can use the same RPC port as bitcoind. We convert // this back to the btcwallet/bitcoind port. rpcPort, err := strconv.Atoi(cfg.ActiveNetParams.RPCPort) if err != nil { return nil, err } rpcPort -= 2 bitcoindHost = fmt.Sprintf("%v:%d", bitcoindMode.RPCHost, rpcPort) if (cfg.Bitcoin.Active && cfg.Bitcoin.RegTest) || (cfg.Litecoin.Active && cfg.Litecoin.RegTest) { conn, err := net.Dial("tcp", bitcoindHost) if err != nil || conn == nil { if cfg.Bitcoin.Active && cfg.Bitcoin.RegTest { rpcPort = 18443 } else if cfg.Litecoin.Active && cfg.Litecoin.RegTest { rpcPort = 19443 } bitcoindHost = fmt.Sprintf("%v:%d", bitcoindMode.RPCHost, rpcPort) } else { conn.Close() } } } // Establish the connection to bitcoind and create the clients // required for our relevant subsystems. bitcoindConn, err := chain.NewBitcoindConn( cfg.ActiveNetParams.Params, bitcoindHost, bitcoindMode.RPCUser, bitcoindMode.RPCPass, bitcoindMode.ZMQPubRawBlock, bitcoindMode.ZMQPubRawTx, 5*time.Second, ) if err != nil { return nil, err } if err := bitcoindConn.Start(); err != nil { return nil, fmt.Errorf("unable to connect to bitcoind: "+ "%v", err) } cc.ChainNotifier = bitcoindnotify.New( bitcoindConn, cfg.ActiveNetParams.Params, hintCache, hintCache, ) cc.ChainView = chainview.NewBitcoindFilteredChainView(bitcoindConn) walletConfig.ChainSource = bitcoindConn.NewBitcoindClient() // If we're not in regtest mode, then we'll attempt to use a // proper fee estimator for testnet. rpcConfig := &rpcclient.ConnConfig{ Host: bitcoindHost, User: bitcoindMode.RPCUser, Pass: bitcoindMode.RPCPass, DisableConnectOnNew: true, DisableAutoReconnect: false, DisableTLS: true, HTTPPostMode: true, } if cfg.Bitcoin.Active && !cfg.Bitcoin.RegTest { log.Infof("Initializing bitcoind backed fee estimator in "+ "%s mode", bitcoindMode.EstimateMode) // Finally, we'll re-initialize the fee estimator, as // if we're using bitcoind as a backend, then we can // use live fee estimates, rather than a statically // coded value. fallBackFeeRate := chainfee.SatPerKVByte(25 * 1000) cc.FeeEstimator, err = chainfee.NewBitcoindEstimator( *rpcConfig, bitcoindMode.EstimateMode, fallBackFeeRate.FeePerKWeight(), ) if err != nil { return nil, err } } else if cfg.Litecoin.Active && !cfg.Litecoin.RegTest { log.Infof("Initializing litecoind backed fee estimator in "+ "%s mode", bitcoindMode.EstimateMode) // Finally, we'll re-initialize the fee estimator, as // if we're using litecoind as a backend, then we can // use live fee estimates, rather than a statically // coded value. fallBackFeeRate := chainfee.SatPerKVByte(25 * 1000) cc.FeeEstimator, err = chainfee.NewBitcoindEstimator( *rpcConfig, bitcoindMode.EstimateMode, fallBackFeeRate.FeePerKWeight(), ) if err != nil { return nil, err } } case "btcd", "ltcd": // Otherwise, we'll be speaking directly via RPC to a node. // // So first we'll load btcd/ltcd's TLS cert for the RPC // connection. If a raw cert was specified in the config, then // we'll set that directly. Otherwise, we attempt to read the // cert from the path specified in the config. var btcdMode *lncfg.Btcd switch { case cfg.Bitcoin.Active: btcdMode = cfg.BtcdMode case cfg.Litecoin.Active: btcdMode = cfg.LtcdMode } var rpcCert []byte if btcdMode.RawRPCCert != "" { rpcCert, err = hex.DecodeString(btcdMode.RawRPCCert) if err != nil { return nil, err } } else { certFile, err := os.Open(btcdMode.RPCCert) if err != nil { return nil, err } rpcCert, err = ioutil.ReadAll(certFile) if err != nil { return nil, err } if err := certFile.Close(); err != nil { return nil, err } } // If the specified host for the btcd/ltcd RPC server already // has a port specified, then we use that directly. Otherwise, // we assume the default port according to the selected chain // parameters. var btcdHost string if strings.Contains(btcdMode.RPCHost, ":") { btcdHost = btcdMode.RPCHost } else { btcdHost = fmt.Sprintf("%v:%v", btcdMode.RPCHost, cfg.ActiveNetParams.RPCPort) } btcdUser := btcdMode.RPCUser btcdPass := btcdMode.RPCPass rpcConfig := &rpcclient.ConnConfig{ Host: btcdHost, Endpoint: "ws", User: btcdUser, Pass: btcdPass, Certificates: rpcCert, DisableTLS: false, DisableConnectOnNew: true, DisableAutoReconnect: false, } cc.ChainNotifier, err = btcdnotify.New( rpcConfig, cfg.ActiveNetParams.Params, hintCache, hintCache, ) if err != nil { return nil, err } // Finally, we'll create an instance of the default chain view to be // used within the routing layer. cc.ChainView, err = chainview.NewBtcdFilteredChainView(*rpcConfig) if err != nil { log.Errorf("unable to create chain view: %v", err) return nil, err } // Create a special websockets rpc client for btcd which will be used // by the wallet for notifications, calls, etc. chainRPC, err := chain.NewRPCClient(cfg.ActiveNetParams.Params, btcdHost, btcdUser, btcdPass, rpcCert, false, 20) if err != nil { return nil, err } walletConfig.ChainSource = chainRPC // If we're not in simnet or regtest mode, then we'll attempt // to use a proper fee estimator for testnet. if !cfg.Bitcoin.SimNet && !cfg.Litecoin.SimNet && !cfg.Bitcoin.RegTest && !cfg.Litecoin.RegTest { log.Info("Initializing btcd backed fee estimator") // Finally, we'll re-initialize the fee estimator, as // if we're using btcd as a backend, then we can use // live fee estimates, rather than a statically coded // value. fallBackFeeRate := chainfee.SatPerKVByte(25 * 1000) cc.FeeEstimator, err = chainfee.NewBtcdEstimator( *rpcConfig, fallBackFeeRate.FeePerKWeight(), ) if err != nil { return nil, err } } default: return nil, fmt.Errorf("unknown node type: %s", homeChainConfig.Node) } // Override default fee estimator if an external service is specified. if cfg.FeeURL != "" { // Do not cache fees on regtest to make it easier to execute // manual or automated test cases. cacheFees := !cfg.Bitcoin.RegTest log.Infof("Using external fee estimator %v: cached=%v", cfg.FeeURL, cacheFees) cc.FeeEstimator = chainfee.NewWebAPIEstimator( chainfee.SparseConfFeeSource{ URL: cfg.FeeURL, }, !cacheFees, ) } // Start fee estimator. if err := cc.FeeEstimator.Start(); err != nil { return nil, err } wc, err := btcwallet.New(*walletConfig) if err != nil { fmt.Printf("unable to create wallet controller: %v\n", err) return nil, err } cc.MsgSigner = wc cc.Signer = wc cc.ChainIO = wc cc.Wc = wc // Select the default channel constraints for the primary chain. channelConstraints := DefaultBtcChannelConstraints if cfg.PrimaryChain() == LitecoinChain { channelConstraints = DefaultLtcChannelConstraints } keyRing := keychain.NewBtcWalletKeyRing( wc.InternalWallet(), cfg.ActiveNetParams.CoinType, ) cc.KeyRing = keyRing // Create, and start the lnwallet, which handles the core payment // channel logic, and exposes control via proxy state machines. walletCfg := lnwallet.Config{ Database: cfg.RemoteChanDB, Notifier: cc.ChainNotifier, WalletController: wc, Signer: cc.Signer, FeeEstimator: cc.FeeEstimator, SecretKeyRing: keyRing, ChainIO: cc.ChainIO, DefaultConstraints: channelConstraints, NetParams: *cfg.ActiveNetParams.Params, } lnWallet, err := lnwallet.NewLightningWallet(walletCfg) if err != nil { fmt.Printf("unable to create wallet: %v\n", err) return nil, err } if err := lnWallet.Startup(); err != nil { fmt.Printf("unable to start wallet: %v\n", err) return nil, err } log.Info("LightningWallet opened") cc.Wallet = lnWallet return cc, nil } var ( // BitcoinTestnetGenesis is the genesis hash of Bitcoin's testnet // chain. BitcoinTestnetGenesis = chainhash.Hash([chainhash.HashSize]byte{ 0x43, 0x49, 0x7f, 0xd7, 0xf8, 0x26, 0x95, 0x71, 0x08, 0xf4, 0xa3, 0x0f, 0xd9, 0xce, 0xc3, 0xae, 0xba, 0x79, 0x97, 0x20, 0x84, 0xe9, 0x0e, 0xad, 0x01, 0xea, 0x33, 0x09, 0x00, 0x00, 0x00, 0x00, }) // BitcoinMainnetGenesis is the genesis hash of Bitcoin's main chain. BitcoinMainnetGenesis = chainhash.Hash([chainhash.HashSize]byte{ 0x6f, 0xe2, 0x8c, 0x0a, 0xb6, 0xf1, 0xb3, 0x72, 0xc1, 0xa6, 0xa2, 0x46, 0xae, 0x63, 0xf7, 0x4f, 0x93, 0x1e, 0x83, 0x65, 0xe1, 0x5a, 0x08, 0x9c, 0x68, 0xd6, 0x19, 0x00, 0x00, 0x00, 0x00, 0x00, }) // LitecoinTestnetGenesis is the genesis hash of Litecoin's testnet4 // chain. LitecoinTestnetGenesis = chainhash.Hash([chainhash.HashSize]byte{ 0xa0, 0x29, 0x3e, 0x4e, 0xeb, 0x3d, 0xa6, 0xe6, 0xf5, 0x6f, 0x81, 0xed, 0x59, 0x5f, 0x57, 0x88, 0x0d, 0x1a, 0x21, 0x56, 0x9e, 0x13, 0xee, 0xfd, 0xd9, 0x51, 0x28, 0x4b, 0x5a, 0x62, 0x66, 0x49, }) // LitecoinMainnetGenesis is the genesis hash of Litecoin's main chain. LitecoinMainnetGenesis = chainhash.Hash([chainhash.HashSize]byte{ 0xe2, 0xbf, 0x04, 0x7e, 0x7e, 0x5a, 0x19, 0x1a, 0xa4, 0xef, 0x34, 0xd3, 0x14, 0x97, 0x9d, 0xc9, 0x98, 0x6e, 0x0f, 0x19, 0x25, 0x1e, 0xda, 0xba, 0x59, 0x40, 0xfd, 0x1f, 0xe3, 0x65, 0xa7, 0x12, }) // chainMap is a simple index that maps a chain's genesis hash to the // ChainCode enum for that chain. chainMap = map[chainhash.Hash]ChainCode{ BitcoinTestnetGenesis: BitcoinChain, LitecoinTestnetGenesis: LitecoinChain, BitcoinMainnetGenesis: BitcoinChain, LitecoinMainnetGenesis: LitecoinChain, } // ChainDNSSeeds is a map of a chain's hash to the set of DNS seeds // that will be use to bootstrap peers upon first startup. // // The first item in the array is the primary host we'll use to attempt // the SRV lookup we require. If we're unable to receive a response // over UDP, then we'll fall back to manual TCP resolution. The second // item in the array is a special A record that we'll query in order to // receive the IP address of the current authoritative DNS server for // the network seed. // // TODO(roasbeef): extend and collapse these and chainparams.go into // struct like chaincfg.Params ChainDNSSeeds = map[chainhash.Hash][][2]string{ BitcoinMainnetGenesis: { { "nodes.lightning.directory", "soa.nodes.lightning.directory", }, { "lseed.bitcoinstats.com", }, }, BitcoinTestnetGenesis: { { "test.nodes.lightning.directory", "soa.nodes.lightning.directory", }, }, LitecoinMainnetGenesis: { { "ltc.nodes.lightning.directory", "soa.nodes.lightning.directory", }, }, } ) // ChainRegistry keeps track of the current chains type ChainRegistry struct { sync.RWMutex activeChains map[ChainCode]*ChainControl netParams map[ChainCode]*BitcoinNetParams primaryChain ChainCode } // NewChainRegistry creates a new ChainRegistry. func NewChainRegistry() *ChainRegistry { return &ChainRegistry{ activeChains: make(map[ChainCode]*ChainControl), netParams: make(map[ChainCode]*BitcoinNetParams), } } // RegisterChain assigns an active ChainControl instance to a target chain // identified by its ChainCode. func (c *ChainRegistry) RegisterChain(newChain ChainCode, cc *ChainControl) { c.Lock() c.activeChains[newChain] = cc c.Unlock() } // LookupChain attempts to lookup an active ChainControl instance for the // target chain. func (c *ChainRegistry) LookupChain(targetChain ChainCode) ( *ChainControl, bool) { c.RLock() cc, ok := c.activeChains[targetChain] c.RUnlock() return cc, ok } // LookupChainByHash attempts to look up an active ChainControl which // corresponds to the passed genesis hash. func (c *ChainRegistry) LookupChainByHash(chainHash chainhash.Hash) (*ChainControl, bool) { c.RLock() defer c.RUnlock() targetChain, ok := chainMap[chainHash] if !ok { return nil, ok } cc, ok := c.activeChains[targetChain] return cc, ok } // RegisterPrimaryChain sets a target chain as the "home chain" for lnd. func (c *ChainRegistry) RegisterPrimaryChain(cc ChainCode) { c.Lock() defer c.Unlock() c.primaryChain = cc } // PrimaryChain returns the primary chain for this running lnd instance. The // primary chain is considered the "home base" while the other registered // chains are treated as secondary chains. func (c *ChainRegistry) PrimaryChain() ChainCode { c.RLock() defer c.RUnlock() return c.primaryChain } // ActiveChains returns a slice containing the active chains. func (c *ChainRegistry) ActiveChains() []ChainCode { c.RLock() defer c.RUnlock() chains := make([]ChainCode, 0, len(c.activeChains)) for activeChain := range c.activeChains { chains = append(chains, activeChain) } return chains } // NumActiveChains returns the total number of active chains. func (c *ChainRegistry) NumActiveChains() uint32 { c.RLock() defer c.RUnlock() return uint32(len(c.activeChains)) }