lnd.xprv/chainregistry.go
Olaoluwa Osuntokun f58b00ef55
multi: split database storage into remote and local instances
In this commit, we split the database storage into two classes: remote
and local data. If etcd isn't active, then everything is actually just
local though we use two pointers everywhere. If etcd is active, then
everything but the graph goes into the remote database.
2020-08-07 18:44:02 -07:00

844 lines
25 KiB
Go

package lnd
import (
"encoding/hex"
"fmt"
"io/ioutil"
"net"
"os"
"path/filepath"
"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/btcsuite/btcwallet/walletdb"
"github.com/lightninglabs/neutrino"
"github.com/lightninglabs/neutrino/headerfs"
"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"
)
const (
// defaultBitcoinMinHTLCMSat 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,
}
// chainCode is an enum-like structure for keeping track of the chains
// currently supported within lnd.
type chainCode uint32
const (
// bitcoinChain is Bitcoin's testnet chain.
bitcoinChain chainCode = iota
// litecoinChain is Litecoin's testnet chain.
litecoinChain
)
// String returns a string representation of the target chainCode.
func (c chainCode) String() string {
switch c {
case bitcoinChain:
return "bitcoin"
case litecoinChain:
return "litecoin"
default:
return "kekcoin"
}
}
// 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 lnwallet.BlockChainIO
feeEstimator chainfee.Estimator
signer input.Signer
keyRing keychain.SecretKeyRing
wc lnwallet.WalletController
msgSigner lnwallet.MessageSigner
chainNotifier chainntnfs.ChainNotifier
chainView chainview.FilteredChainView
wallet *lnwallet.LightningWallet
routingPolicy htlcswitch.ForwardingPolicy
minHtlcIn lnwire.MilliSatoshi
}
// newChainControlFromConfig attempts to create a chainControl instance
// according to the parameters in the passed lnd 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 newChainControlFromConfig(cfg *Config, localDB, remoteDB *channeldb.DB,
privateWalletPw, publicWalletPw []byte, birthday time.Time,
recoveryWindow uint32, wallet *wallet.Wallet,
neutrinoCS *neutrino.ChainService) (*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.registeredChains.PrimaryChain() == litecoinChain {
homeChainConfig = cfg.Litecoin
}
ltndLog.Infof("Primary chain is set to: %v",
cfg.registeredChains.PrimaryChain())
cc := &chainControl{}
switch cfg.registeredChains.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.registeredChains.PrimaryChain())
}
walletConfig := &btcwallet.Config{
PrivatePass: privateWalletPw,
PublicPass: publicWalletPw,
Birthday: birthday,
RecoveryWindow: recoveryWindow,
DataDir: homeChainConfig.ChainDir,
NetParams: activeNetParams.Params,
CoinType: activeNetParams.CoinType,
Wallet: wallet,
}
var err error
heightHintCacheConfig := chainntnfs.CacheConfig{
QueryDisable: cfg.HeightHintCacheQueryDisable,
}
if cfg.HeightHintCacheQueryDisable {
ltndLog.Infof("Height Hint Cache Queries disabled")
}
// Initialize the height hint cache within the chain directory.
hintCache, err := chainntnfs.NewHeightHintCache(heightHintCacheConfig, localDB)
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(
neutrinoCS, hintCache, hintCache,
)
cc.chainView, err = chainview.NewCfFilteredChainView(neutrinoCS)
if err != nil {
return nil, err
}
// If the user provided an API for fee estimation, activate it now.
if cfg.NeutrinoMode.FeeURL != "" {
ltndLog.Infof("Using API fee estimator!")
estimator := chainfee.NewWebAPIEstimator(
chainfee.SparseConfFeeSource{
URL: cfg.NeutrinoMode.FeeURL,
},
defaultBitcoinStaticFeePerKW,
)
if err := estimator.Start(); err != nil {
return nil, err
}
cc.feeEstimator = estimator
}
walletConfig.ChainSource = chain.NewNeutrinoClient(
activeNetParams.Params, 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(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(
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, 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 {
ltndLog.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
}
if err := cc.feeEstimator.Start(); err != nil {
return nil, err
}
} else if cfg.Litecoin.Active && !cfg.Litecoin.RegTest {
ltndLog.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
}
if err := cc.feeEstimator.Start(); 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,
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, 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 {
srvrLog.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(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 {
ltndLog.Infof("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
}
if err := cc.feeEstimator.Start(); err != nil {
return nil, err
}
}
default:
return nil, fmt.Errorf("unknown node type: %s",
homeChainConfig.Node)
}
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.registeredChains.PrimaryChain() == litecoinChain {
channelConstraints = defaultLtcChannelConstraints
}
keyRing := keychain.NewBtcWalletKeyRing(
wc.InternalWallet(), 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: remoteDB,
Notifier: cc.chainNotifier,
WalletController: wc,
Signer: cc.signer,
FeeEstimator: cc.feeEstimator,
SecretKeyRing: keyRing,
ChainIO: cc.chainIO,
DefaultConstraints: channelConstraints,
NetParams: *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
}
ltndLog.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))
}
// initNeutrinoBackend inits a new instance of the neutrino light client
// backend given a target chain directory to store the chain state.
func initNeutrinoBackend(cfg *Config, chainDir string) (*neutrino.ChainService,
func(), error) {
// First we'll open the database file for neutrino, creating the
// database if needed. We append the normalized network name here to
// match the behavior of btcwallet.
dbPath := filepath.Join(
chainDir,
normalizeNetwork(activeNetParams.Name),
)
// Ensure that the neutrino db path exists.
if err := os.MkdirAll(dbPath, 0700); err != nil {
return nil, nil, err
}
dbName := filepath.Join(dbPath, "neutrino.db")
db, err := walletdb.Create("bdb", dbName, !cfg.SyncFreelist)
if err != nil {
return nil, nil, fmt.Errorf("unable to create neutrino "+
"database: %v", err)
}
headerStateAssertion, err := parseHeaderStateAssertion(
cfg.NeutrinoMode.AssertFilterHeader,
)
if err != nil {
db.Close()
return nil, nil, err
}
// With the database open, we can now create an instance of the
// neutrino light client. We pass in relevant configuration parameters
// required.
config := neutrino.Config{
DataDir: dbPath,
Database: db,
ChainParams: *activeNetParams.Params,
AddPeers: cfg.NeutrinoMode.AddPeers,
ConnectPeers: cfg.NeutrinoMode.ConnectPeers,
Dialer: func(addr net.Addr) (net.Conn, error) {
return cfg.net.Dial(addr.Network(), addr.String())
},
NameResolver: func(host string) ([]net.IP, error) {
addrs, err := cfg.net.LookupHost(host)
if err != nil {
return nil, err
}
ips := make([]net.IP, 0, len(addrs))
for _, strIP := range addrs {
ip := net.ParseIP(strIP)
if ip == nil {
continue
}
ips = append(ips, ip)
}
return ips, nil
},
AssertFilterHeader: headerStateAssertion,
}
neutrino.MaxPeers = 8
neutrino.BanDuration = time.Hour * 48
neutrinoCS, err := neutrino.NewChainService(config)
if err != nil {
db.Close()
return nil, nil, fmt.Errorf("unable to create neutrino light "+
"client: %v", err)
}
if err := neutrinoCS.Start(); err != nil {
db.Close()
return nil, nil, err
}
cleanUp := func() {
neutrinoCS.Stop()
db.Close()
}
return neutrinoCS, cleanUp, nil
}
// parseHeaderStateAssertion parses the user-specified neutrino header state
// into a headerfs.FilterHeader.
func parseHeaderStateAssertion(state string) (*headerfs.FilterHeader, error) {
if len(state) == 0 {
return nil, nil
}
split := strings.Split(state, ":")
if len(split) != 2 {
return nil, fmt.Errorf("header state assertion %v in "+
"unexpected format, expected format height:hash", state)
}
height, err := strconv.ParseUint(split[0], 10, 32)
if err != nil {
return nil, fmt.Errorf("invalid filter header height: %v", err)
}
hash, err := chainhash.NewHashFromStr(split[1])
if err != nil {
return nil, fmt.Errorf("invalid filter header hash: %v", err)
}
return &headerfs.FilterHeader{
Height: uint32(height),
FilterHash: *hash,
}, nil
}