lnd.xprv/server.go
Olaoluwa Osuntokun 4fe23a8b3e
lnd: switch over to using brontide for p2p connections
This commit modifies the existing p2p connection authentication and
encryption scheme to now use the newly designed ‘brontide’
authenticated key agreement scheme for all connections.

Additionally, within the daemon lnwire.NetAddress is now used within
all peers which encapsulates host information, a node’s identity public
key relevant services, and supported bitcoin nets.
2016-10-27 19:49:17 -07:00

534 lines
14 KiB
Go

package main
import (
"encoding/hex"
"fmt"
"net"
"sync"
"sync/atomic"
"github.com/btcsuite/fastsha256"
"github.com/lightningnetwork/lightning-onion"
"github.com/lightningnetwork/lnd/brontide"
"github.com/lightningnetwork/lnd/chainntnfs"
"github.com/lightningnetwork/lnd/channeldb"
"github.com/lightningnetwork/lnd/lnrpc"
"github.com/lightningnetwork/lnd/lnwallet"
"github.com/lightningnetwork/lnd/lnwire"
"github.com/roasbeef/btcd/btcec"
"github.com/roasbeef/btcutil"
"github.com/BitfuryLightning/tools/routing"
"github.com/BitfuryLightning/tools/rt/graph"
)
// server is the main server of the Lightning Network Daemon. The server
// houses global state pertianing to the wallet, database, and the rpcserver.
// Additionally, the server is also used as a central messaging bus to interact
// with any of its companion objects.
type server struct {
started int32 // atomic
shutdown int32 // atomic
// identityPriv is the private key used to authenticate any incoming
// connections.
identityPriv *btcec.PrivateKey
// lightningID is the sha256 of the public key corresponding to our
// long-term identity private key.
lightningID [32]byte
listeners []net.Listener
peers map[int32]*peer
rpcServer *rpcServer
chainNotifier chainntnfs.ChainNotifier
bio lnwallet.BlockChainIO
lnwallet *lnwallet.LightningWallet
fundingMgr *fundingManager
chanDB *channeldb.DB
htlcSwitch *htlcSwitch
invoices *invoiceRegistry
routingMgr *routing.RoutingManager
utxoNursery *utxoNursery
sphinx *sphinx.Router
newPeers chan *peer
donePeers chan *peer
queries chan interface{}
wg sync.WaitGroup
quit chan struct{}
}
// newServer creates a new instance of the server which is to listen using the
// passed listener address.
func newServer(listenAddrs []string, notifier chainntnfs.ChainNotifier,
bio lnwallet.BlockChainIO, wallet *lnwallet.LightningWallet,
chanDB *channeldb.DB) (*server, error) {
privKey, err := wallet.GetIdentitykey()
if err != nil {
return nil, err
}
listeners := make([]net.Listener, len(listenAddrs))
for i, addr := range listenAddrs {
listeners[i], err = brontide.NewListener(privKey, addr)
if err != nil {
return nil, err
}
}
serializedPubKey := privKey.PubKey().SerializeCompressed()
s := &server{
bio: bio,
chainNotifier: notifier,
chanDB: chanDB,
fundingMgr: newFundingManager(wallet),
invoices: newInvoiceRegistry(chanDB),
lnwallet: wallet,
identityPriv: privKey,
// TODO(roasbeef): derive proper onion key based on rotation
// schedule
sphinx: sphinx.NewRouter(privKey, activeNetParams.Params),
lightningID: fastsha256.Sum256(serializedPubKey),
listeners: listeners,
peers: make(map[int32]*peer),
newPeers: make(chan *peer, 100),
donePeers: make(chan *peer, 100),
queries: make(chan interface{}),
quit: make(chan struct{}),
}
// If the debug HTLC flag is on, then we invoice a "master debug"
// invoice which all outgoing payments will be sent and all incoming
// HTLC's with the debug R-Hash immediately settled.
if cfg.DebugHTLC {
kiloCoin := btcutil.Amount(btcutil.SatoshiPerBitcoin * 1000)
s.invoices.AddDebugInvoice(kiloCoin, *debugPre)
srvrLog.Debugf("Debug HTLC invoice inserted, preimage=%x, hash=%x",
debugPre[:], debugHash[:])
}
s.utxoNursery = newUtxoNursery(notifier, wallet)
// Create a new routing manager with ourself as the sole node within
// the graph.
selfVertex := hex.EncodeToString(serializedPubKey)
s.routingMgr = routing.NewRoutingManager(graph.NewID(selfVertex), nil)
s.htlcSwitch = newHtlcSwitch(serializedPubKey, s.routingMgr)
s.rpcServer = newRpcServer(s)
return s, nil
}
// Start starts the main daemon server, all requested listeners, and any helper
// goroutines.
func (s *server) Start() error {
// Already running?
if atomic.AddInt32(&s.started, 1) != 1 {
return nil
}
// Start all the listeners.
for _, l := range s.listeners {
s.wg.Add(1)
go s.listener(l)
}
// Start the notification server. This is used so channel managment
// goroutines can be notified when a funding transaction reaches a
// sufficient number of confirmations, or when the input for the
// funding transaction is spent in an attempt at an uncooperative
// close by the counter party.
if err := s.chainNotifier.Start(); err != nil {
return err
}
if err := s.rpcServer.Start(); err != nil {
return err
}
if err := s.fundingMgr.Start(); err != nil {
return err
}
if err := s.htlcSwitch.Start(); err != nil {
return err
}
if err := s.utxoNursery.Start(); err != nil {
return err
}
s.routingMgr.Start()
s.wg.Add(1)
go s.queryHandler()
return nil
}
// Stop gracefully shutsdown the main daemon server. This function will signal
// any active goroutines, or helper objects to exit, then blocks until they've
// all successfully exited. Additionally, any/all listeners are closed.
func (s *server) Stop() error {
// Bail if we're already shutting down.
if atomic.AddInt32(&s.shutdown, 1) != 1 {
return nil
}
// Stop all the listeners.
for _, listener := range s.listeners {
if err := listener.Close(); err != nil {
return err
}
}
// Shutdown the wallet, funding manager, and the rpc server.
s.chainNotifier.Stop()
s.rpcServer.Stop()
s.fundingMgr.Stop()
s.routingMgr.Stop()
s.htlcSwitch.Stop()
s.utxoNursery.Stop()
s.lnwallet.Shutdown()
// Signal all the lingering goroutines to quit.
close(s.quit)
s.wg.Wait()
return nil
}
// WaitForShutdown blocks all goroutines have been stopped.
func (s *server) WaitForShutdown() {
s.wg.Wait()
}
// addPeer adds the passed peer to the server's global state of all active
// peers.
func (s *server) addPeer(p *peer) {
if p == nil {
return
}
// Ignore new peers if we're shutting down.
if atomic.LoadInt32(&s.shutdown) != 0 {
p.Stop()
return
}
s.peers[p.id] = p
}
// removePeer removes the passed peer from the server's state of all active
// peers.
func (s *server) removePeer(p *peer) {
srvrLog.Debugf("removing peer %v", p)
if p == nil {
return
}
// Ignore deleting peers if we're shutting down.
if atomic.LoadInt32(&s.shutdown) != 0 {
p.Stop()
return
}
delete(s.peers, p.id)
}
// connectPeerMsg is a message requesting the server to open a connection to a
// particular peer. This message also houses an error channel which will be
// used to report success/failure.
type connectPeerMsg struct {
addr *lnwire.NetAddress
resp chan int32
err chan error
}
// listPeersMsg is a message sent to the server in order to obtain a listing
// of all currently active channels.
type listPeersMsg struct {
resp chan []*peer
}
// openChanReq is a message sent to the server in order to request the
// initiation of a channel funding workflow to the peer with either the specified
// relative peer ID, or a global lightning ID.
type openChanReq struct {
targetPeerID int32
targetPubkey *btcec.PublicKey
// TODO(roasbeef): make enums in lnwire
channelType uint8
coinType uint64
localFundingAmt btcutil.Amount
remoteFundingAmt btcutil.Amount
numConfs uint32
updates chan *lnrpc.OpenStatusUpdate
err chan error
}
// queryHandler handles any requests to modify the server's internal state of
// all active peers, or query/mutate the server's global state. Additionally,
// any queries directed at peers will be handled by this goroutine.
//
// NOTE: This MUST be run as a goroutine.
func (s *server) queryHandler() {
out:
for {
select {
// New peers.
case p := <-s.newPeers:
s.addPeer(p)
// Finished peers.
case p := <-s.donePeers:
s.removePeer(p)
case query := <-s.queries:
// TODO(roasbeef): make all goroutines?
switch msg := query.(type) {
case *connectPeerMsg:
s.handleConnectPeer(msg)
case *listPeersMsg:
s.handleListPeers(msg)
case *openChanReq:
s.handleOpenChanReq(msg)
}
case msg := <-s.routingMgr.ChOut:
msg1 := msg.(*routing.RoutingMessage)
if msg1.ReceiverID == nil {
peerLog.Critical("msg1.GetReceiverID() == nil")
continue
}
receiverID := msg1.ReceiverID.String()
var targetPeer *peer
for _, peer := range s.peers { // TODO: threadsafe api
nodePub := peer.addr.IdentityKey.SerializeCompressed()
idStr := hex.EncodeToString(nodePub)
// We found the the target
if receiverID == idStr {
targetPeer = peer
break
}
}
if targetPeer != nil {
targetPeer.queueMsg(msg1.Msg, nil)
} else {
srvrLog.Errorf("Can't find peer to send message %v",
receiverID)
}
case <-s.quit:
break out
}
}
s.wg.Done()
}
// handleListPeers sends a lice of all currently active peers to the original
// caller.
func (s *server) handleListPeers(msg *listPeersMsg) {
peers := make([]*peer, 0, len(s.peers))
for _, peer := range s.peers {
peers = append(peers, peer)
}
msg.resp <- peers
}
// handleConnectPeer attempts to establish a connection to the address enclosed
// within the passed connectPeerMsg. This function is *async*, a goroutine will
// be spawned in order to finish the request, and respond to the caller.
func (s *server) handleConnectPeer(msg *connectPeerMsg) {
addr := msg.addr
// Ensure we're not already connected to this
// peer.
targetPub := msg.addr.IdentityKey
for _, peer := range s.peers {
if peer.addr.IdentityKey.IsEqual(targetPub) {
msg.err <- fmt.Errorf(
"already connected to peer: %v",
peer.addr,
)
msg.resp <- -1
return
}
}
// Launch a goroutine to connect to the requested peer so we can
// continue to handle queries.
//
// TODO(roasbeef): semaphore to limit the number of goroutines for
// async requests.
go func() {
srvrLog.Debugf("connecting to %v", addr)
// Attempt to connect to the remote node. If the we can't make
// the connection, or the crypto negotation breaks down, then
// return an error to the caller.
conn, err := brontide.Dial(s.identityPriv, addr)
if err != nil {
msg.err <- err
msg.resp <- -1
return
}
// Now that we've established a connection, create a peer, and
// it to the set of currently active peers.
peer, err := newPeer(conn, s, msg.addr, false)
if err != nil {
srvrLog.Errorf("unable to create peer %v", err)
conn.Close()
msg.resp <- -1
msg.err <- err
return
}
// TODO(roasbeef): update IP address for link-node
// * also mark last-seen, do it one single transaction?
peer.Start()
s.newPeers <- peer
msg.resp <- peer.id
msg.err <- nil
}()
}
// handleOpenChanReq first locates the target peer, and if found hands off the
// request to the funding manager allowing it to initiate the channel funding
// workflow.
func (s *server) handleOpenChanReq(req *openChanReq) {
// First attempt to locate the target peer to open a channel with, if
// we're unable to locate the peer then this request will fail.
var targetPeer *peer
for _, peer := range s.peers { // TODO(roasbeef): threadsafe api
// We found the the target
if peer.addr.IdentityKey.IsEqual(req.targetPubkey) ||
req.targetPeerID == peer.id {
targetPeer = peer
break
}
}
if targetPeer == nil {
req.err <- fmt.Errorf("unable to find peer nodeID(%x), "+
"peerID(%v)", req.targetPubkey.SerializeCompressed(),
req.targetPeerID)
return
}
// Spawn a goroutine to send the funding workflow request to the funding
// manager. This allows the server to continue handling queries instead of
// blocking on this request which is exporeted as a synchronous request to
// the outside world.
// TODO(roasbeef): server semaphore to restrict num goroutines
go s.fundingMgr.initFundingWorkflow(targetPeer, req)
}
// ConnectToPeer requests that the server connect to a Lightning Network peer
// at the specified address. This function will *block* until either a
// connection is established, or the initial handshake process fails.
func (s *server) ConnectToPeer(addr *lnwire.NetAddress) (int32, error) {
reply := make(chan int32, 1)
errChan := make(chan error, 1)
s.queries <- &connectPeerMsg{addr, reply, errChan}
return <-reply, <-errChan
}
// OpenChannel sends a request to the server to open a channel to the specified
// peer identified by ID with the passed channel funding paramters.
func (s *server) OpenChannel(peerID int32, nodeKey *btcec.PublicKey,
localAmt, remoteAmt btcutil.Amount,
numConfs uint32) (chan *lnrpc.OpenStatusUpdate, chan error) {
errChan := make(chan error, 1)
updateChan := make(chan *lnrpc.OpenStatusUpdate, 1)
req := &openChanReq{
targetPeerID: peerID,
targetPubkey: nodeKey,
localFundingAmt: localAmt,
remoteFundingAmt: remoteAmt,
numConfs: numConfs,
updates: updateChan,
err: errChan,
}
s.queries <- req
return updateChan, errChan
}
// Peers returns a slice of all active peers.
func (s *server) Peers() []*peer {
resp := make(chan []*peer)
s.queries <- &listPeersMsg{resp}
return <-resp
}
// listener is a goroutine dedicated to accepting in coming peer connections
// from the passed listener.
//
// NOTE: This MUST be run as a goroutine.
func (s *server) listener(l net.Listener) {
srvrLog.Infof("Server listening on %s", l.Addr())
for atomic.LoadInt32(&s.shutdown) == 0 {
conn, err := l.Accept()
if err != nil {
// Only log the error message if we aren't currently
// shutting down.
if atomic.LoadInt32(&s.shutdown) == 0 {
srvrLog.Errorf("Can't accept connection: %v", err)
}
continue
}
srvrLog.Tracef("New inbound connection from %v", conn.RemoteAddr())
brontideConn := conn.(*brontide.Conn)
peerAddr := &lnwire.NetAddress{
IdentityKey: brontideConn.RemotePub(),
Address: conn.RemoteAddr().(*net.TCPAddr),
ChainNet: activeNetParams.Net,
}
peer, err := newPeer(conn, s, peerAddr, true)
if err != nil {
srvrLog.Errorf("unable to create peer: %v", err)
conn.Close()
continue
}
// TODO(roasbeef): update IP address for link-node
// * also mark last-seen, do it one single transaction?
peer.Start()
s.newPeers <- peer
}
s.wg.Done()
}