lnd.xprv/chainregistry.go
2017-07-30 17:52:07 -07:00

425 lines
12 KiB
Go

package main
import (
"encoding/hex"
"fmt"
"io/ioutil"
"os"
"path/filepath"
"strings"
"sync"
"time"
"github.com/lightninglabs/neutrino"
"github.com/lightningnetwork/lnd/chainntnfs"
"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/lnwallet"
"github.com/lightningnetwork/lnd/lnwallet/btcwallet"
"github.com/lightningnetwork/lnd/routing/chainview"
"github.com/roasbeef/btcd/chaincfg/chainhash"
"github.com/roasbeef/btcrpcclient"
"github.com/roasbeef/btcwallet/chain"
"github.com/roasbeef/btcwallet/walletdb"
)
// defaultBitcoinForwardingPolicy is the default forwarding policy used for
// Bitcoin channels.
var defaultBitcoinForwardingPolicy = htlcswitch.ForwardingPolicy{
MinHTLC: 0,
BaseFee: 1,
FeeRate: 1,
TimeLockDelta: 1,
}
// defaultLitecoinForwardingPolicy is the default forwarding policy used for
// Litecoin channels.
var defaultLitecoinForwardingPolicy = htlcswitch.ForwardingPolicy{
MinHTLC: 0,
BaseFee: 1,
FeeRate: 1,
TimeLockDelta: 1,
}
// defaultChannelConstraints is the default set of channel constraints that are
// meant to be used when initially funding a channel.
//
// TODO(roasbeef): have one for both chains
var defaultChannelConstraints = channeldb.ChannelConstraints{
DustLimit: lnwallet.DefaultDustLimit(),
MaxAcceptedHtlcs: lnwallet.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 lnwallet.FeeEstimator
signer lnwallet.Signer
msgSigner lnwallet.MessageSigner
chainNotifier chainntnfs.ChainNotifier
chainView chainview.FilteredChainView
wallet *lnwallet.LightningWallet
routingPolicy htlcswitch.ForwardingPolicy
}
// newChainControlFromConfig attempts to create a chainControl instance
// according to the parameters in the passed lnd configuration. Currently two
// branches of chainControl instances exist: one backed by a running btcd
// full-node, and the other backed by a running neutrino light client instance.
func newChainControlFromConfig(cfg *config, chanDB *channeldb.DB) (*chainControl, func(), 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 registeredChains.PrimaryChain() == litecoinChain {
homeChainConfig = cfg.Litecoin
}
ltndLog.Infof("Primary chain is set to: %v",
registeredChains.PrimaryChain())
estimator := lnwallet.StaticFeeEstimator{FeeRate: 50}
walletConfig := &btcwallet.Config{
PrivatePass: []byte("hello"),
DataDir: homeChainConfig.ChainDir,
NetParams: activeNetParams.Params,
FeeEstimator: estimator,
}
cc := &chainControl{
feeEstimator: estimator,
}
switch registeredChains.PrimaryChain() {
case bitcoinChain:
cc.routingPolicy = defaultBitcoinForwardingPolicy
case litecoinChain:
cc.routingPolicy = defaultLitecoinForwardingPolicy
default:
return nil, nil, fmt.Errorf("Default routing policy for "+
"chain %v is unknown", registeredChains.PrimaryChain())
}
var (
err error
cleanUp func()
)
// If spv mode is active, then we'll be using a distimnct set of
// chainControl interfaces that interface directly with the p2p network
// of the selected chain.
if cfg.NeutrinoMode.Active {
// First we'll open the database file for neutrino, creating
// the database if needed.
dbName := filepath.Join(cfg.DataDir, "neutrino.db")
nodeDatabase, err := walletdb.Create("bdb", dbName)
if err != nil {
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: cfg.DataDir,
Database: nodeDatabase,
ChainParams: *activeNetParams.Params,
AddPeers: cfg.NeutrinoMode.AddPeers,
ConnectPeers: cfg.NeutrinoMode.ConnectPeers,
}
neutrino.WaitForMoreCFHeaders = time.Second * 1
neutrino.MaxPeers = 8
neutrino.BanDuration = 5 * time.Second
svc, err := neutrino.NewChainService(config)
if err != nil {
return nil, nil, fmt.Errorf("unable to create neutrino: %v", err)
}
svc.Start()
// Next we'll create the instances of the ChainNotifier and
// FilteredChainView interface which is backed by the neutrino
// light client.
cc.chainNotifier, err = neutrinonotify.New(svc)
if err != nil {
return nil, nil, err
}
cc.chainView, err = chainview.NewCfFilteredChainView(svc)
if err != nil {
return nil, nil, err
}
// Finally, we'll set the chain source for btcwallet, and
// create our clean up function which simply closes the
// database.
walletConfig.ChainSource = chain.NewNeutrinoClient(svc)
cleanUp = func() {
defer nodeDatabase.Close()
}
} else {
// 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 rpcCert []byte
if homeChainConfig.RawRPCCert != "" {
rpcCert, err = hex.DecodeString(homeChainConfig.RawRPCCert)
if err != nil {
return nil, nil, err
}
} else {
certFile, err := os.Open(homeChainConfig.RPCCert)
if err != nil {
return nil, nil, err
}
rpcCert, err = ioutil.ReadAll(certFile)
if err != nil {
return nil, nil, err
}
if err := certFile.Close(); err != nil {
return nil, 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(homeChainConfig.RPCHost, ":") {
btcdHost = homeChainConfig.RPCHost
} else {
btcdHost = fmt.Sprintf("%v:%v", homeChainConfig.RPCHost,
activeNetParams.rpcPort)
}
btcdUser := homeChainConfig.RPCUser
btcdPass := homeChainConfig.RPCPass
rpcConfig := &btcrpcclient.ConnConfig{
Host: btcdHost,
Endpoint: "ws",
User: btcdUser,
Pass: btcdPass,
Certificates: rpcCert,
DisableTLS: false,
DisableConnectOnNew: true,
DisableAutoReconnect: false,
}
cc.chainNotifier, err = btcdnotify.New(rpcConfig)
if err != nil {
return nil, 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, 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, nil, err
}
walletConfig.ChainSource = chainRPC
}
wc, err := btcwallet.New(*walletConfig)
if err != nil {
fmt.Printf("unable to create wallet controller: %v\n", err)
return nil, nil, err
}
cc.msgSigner = wc
cc.signer = wc
cc.chainIO = wc
// Create, and start the lnwallet, which handles the core payment
// channel logic, and exposes control via proxy state machines.
walletCfg := lnwallet.Config{
Database: chanDB,
Notifier: cc.chainNotifier,
WalletController: wc,
Signer: cc.signer,
FeeEstimator: cc.feeEstimator,
ChainIO: cc.chainIO,
DefaultConstraints: defaultChannelConstraints,
NetParams: *activeNetParams.Params,
}
wallet, err := lnwallet.NewLightningWallet(walletCfg)
if err != nil {
fmt.Printf("unable to create wallet: %v\n", err)
return nil, nil, err
}
if err := wallet.Startup(); err != nil {
fmt.Printf("unable to start wallet: %v\n", err)
return nil, nil, err
}
ltndLog.Info("LightningWallet opened")
cc.wallet = wallet
return cc, cleanUp, nil
}
var (
// bitcoinGenesis is the genesis hash of Bitcoin's testnet chain.
bitcoinGenesis = 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,
})
// litecoinGenesis is the genesis hash of Litecoin's testnet4 chain.
litecoinGenesis = 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,
})
// chainMap is a simple index that maps a chain's genesis hash to the
// chainCode enum for that chain.
chainMap = map[chainhash.Hash]chainCode{
bitcoinGenesis: bitcoinChain,
litecoinGenesis: litecoinChain,
}
// reverseChainMap is the inverse of the chainMap above: it maps the
// chain enum for a chain to its genesis hash.
reverseChainMap = map[chainCode]chainhash.Hash{
bitcoinChain: bitcoinGenesis,
litecoinChain: litecoinGenesis,
}
)
// 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 the total number of 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))
}