lnd.xprv/fundingmanager.go
Olaoluwa Osuntokun 8b432f8ca6
funding: query fee estimator and scale to fee-per-kw when making chan
This commit modifies the funding workflow slightly to move the querying
to the fee estimator (for the new channel) into the fundingManager
rather than within the LightningWallet layer. When querying to
FeePerWeight, we now multiply by 1000 to arrive at fee-per-kw.

Additionally, we now also properly thread through the fee-per-kw
offered by the initiator the to the responder of the channel workflow.
2017-05-16 19:11:00 -07:00

1454 lines
49 KiB
Go

package main
import (
"bytes"
"encoding/binary"
"sync"
"sync/atomic"
"time"
"golang.org/x/crypto/salsa20"
"github.com/davecgh/go-spew/spew"
"github.com/go-errors/errors"
"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/btcd/txscript"
"github.com/roasbeef/btcd/wire"
"github.com/roasbeef/btcutil"
"google.golang.org/grpc"
)
const (
// TODO(roasbeef): tune
msgBufferSize = 50
)
// reservationWithCtx encapsulates a pending channel reservation. This wrapper
// struct is used internally within the funding manager to track and progress
// the funding workflow initiated by incoming/outgoing methods from the target
// peer. Additionally, this struct houses a response and error channel which is
// used to respond to the caller in the case a channel workflow is initiated
// via a local signal such as RPC.
// TODO(roasbeef): actually use the context package
// * deadlines, etc.
type reservationWithCtx struct {
reservation *lnwallet.ChannelReservation
peerAddress *lnwire.NetAddress
updates chan *lnrpc.OpenStatusUpdate
err chan error
}
// initFundingMsg is sent by an outside subsystem to the funding manager in
// order to kick off a funding workflow with a specified target peer. The
// original request which defines the parameters of the funding workflow are
// embedded within this message giving the funding manager full context w.r.t
// the workflow.
type initFundingMsg struct {
peerAddress *lnwire.NetAddress
*openChanReq
}
// fundingRequestMsg couples an lnwire.SingleFundingRequest message with the
// peer who sent the message. This allows the funding manager to queue a
// response directly to the peer, progressing the funding workflow.
type fundingRequestMsg struct {
msg *lnwire.SingleFundingRequest
peerAddress *lnwire.NetAddress
}
// fundingResponseMsg couples an lnwire.SingleFundingResponse message with the
// peer who sent the message. This allows the funding manager to queue a
// response directly to the peer, progressing the funding workflow.
type fundingResponseMsg struct {
msg *lnwire.SingleFundingResponse
peerAddress *lnwire.NetAddress
}
// fundingCompleteMsg couples an lnwire.SingleFundingComplete message with the
// peer who sent the message. This allows the funding manager to queue a
// response directly to the peer, progressing the funding workflow.
type fundingCompleteMsg struct {
msg *lnwire.SingleFundingComplete
peerAddress *lnwire.NetAddress
}
// fundingSignCompleteMsg couples an lnwire.SingleFundingSignComplete message
// with the peer who sent the message. This allows the funding manager to
// queue a response directly to the peer, progressing the funding workflow.
type fundingSignCompleteMsg struct {
msg *lnwire.SingleFundingSignComplete
peerAddress *lnwire.NetAddress
}
// fundingLockedMsg couples an lnwire.FundingLocked message with the peer who
// sent the message. This allows the funding manager to finalize the funding
// process and announce the existence of the new channel.
type fundingLockedMsg struct {
msg *lnwire.FundingLocked
peerAddress *lnwire.NetAddress
}
// fundingErrorMsg couples an lnwire.Error message with the peer who sent the
// message. This allows the funding manager to properly process the error.
type fundingErrorMsg struct {
err *lnwire.Error
peerAddress *lnwire.NetAddress
}
// pendingChannels is a map instantiated per-peer which tracks all active
// pending single funded channels indexed by their pending channel identifier.
type pendingChannels map[[32]byte]*reservationWithCtx
// serializedPubKey is used within the FundingManager's activeReservations list
// to identify the nodes with which the FundingManager is actively working to
// initiate new channels.
type serializedPubKey [33]byte
// newSerializedKey creates a new serialized public key from an instance of a
// live pubkey object.
func newSerializedKey(pubKey *btcec.PublicKey) serializedPubKey {
var s serializedPubKey
copy(s[:], pubKey.SerializeCompressed())
return s
}
// fundingConfig defines the configuration for the FundingManager. All elements
// within the configuration MUST be non-nil for the FundingManager to carry out
// its duties.
type fundingConfig struct {
// IDKey is the PublicKey that is used to identify this node within the
// Lightning Network.
IDKey *btcec.PublicKey
// Wallet handles the parts of the funding process that involves moving
// funds from on-chain transaction outputs into Lightning channels.
Wallet *lnwallet.LightningWallet
// FeeEstimator calculates appropriate fee rates based on historical
// transaction information.
FeeEstimator lnwallet.FeeEstimator
// ArbiterChan allows the FundingManager to notify the BreachArbiter
// that a new channel has been created that should be observed to
// ensure that the channel counterparty hasn't broadcasted an invalid
// commitment transaction.
ArbiterChan chan<- *lnwallet.LightningChannel
// Notifier is used by the FundingManager to determine when the
// channel's funding transaction has been confirmed on the blockchain
// so that the channel creation process can be completed.
Notifier chainntnfs.ChainNotifier
// ChainIO is used by the FundingManager to determine the current
// height so it's able to reduce the search space for certain
// ChainNotifier implementations when registering for confirmations.
ChainIO lnwallet.BlockChainIO
// SignMessage signs an arbitrary method with a given public key. The
// actual digest signed is the double sha-256 of the message. In the
// case that the private key corresponding to the passed public key
// cannot be located, then an error is returned.
SignMessage func(pubKey *btcec.PublicKey, msg []byte) (*btcec.Signature, error)
// SendAnnouncement is used by the FundingManager to announce newly
// created channels to the rest of the Lightning Network.
SendAnnouncement func(msg lnwire.Message) error
// SendToPeer allows the FundingManager to send messages to the peer
// node during the multiple steps involved in the creation of the
// channel's funding transaction and initial commitment transaction.
SendToPeer func(target *btcec.PublicKey, msgs ...lnwire.Message) error
// FindPeer searches the list of peers connected to the node so that
// the FundingManager can notify other daemon subsystems as necessary
// during the funding process.
FindPeer func(peerKey *btcec.PublicKey) (*peer, error)
// FindChannel queries the database for the channel with the given
// channel ID.
FindChannel func(chanID lnwire.ChannelID) (*lnwallet.LightningChannel, error)
// TempChanIDSeed is a cryptographically random string of bytes that's
// used as a seed to generate pending channel ID's.
TempChanIDSeed [32]byte
}
// fundingManager acts as an orchestrator/bridge between the wallet's
// 'ChannelReservation' workflow, and the wire protocol's funding initiation
// messages. Any requests to initiate the funding workflow for a channel,
// either kicked-off locally or remotely handled by the funding manager.
// Once a channel's funding workflow has been completed, any local callers, the
// local peer, and possibly the remote peer are notified of the completion of
// the channel workflow. Additionally, any temporary or permanent access
// controls between the wallet and remote peers are enforced via the funding
// manager.
type fundingManager struct {
// MUST be used atomically.
started int32
stopped int32
// cfg is a copy of the configuration struct that the FundingManager was
// initialized with.
cfg *fundingConfig
// chanIDKey is a cryptographically random key that's used to generate
// temporary channel ID's.
chanIDKey [32]byte
// chanIDNonce is a nonce that's incremented for each new funding
// reservation created.
nonceMtx sync.RWMutex
chanIDNonce uint64
// channelReservations is a map which houses the state of all pending
// funding workflows.
resMtx sync.RWMutex
activeReservations map[serializedPubKey]pendingChannels
// fundingMsgs is a channel which receives wrapped wire messages
// related to funding workflow from outside peers.
fundingMsgs chan interface{}
// queries is a channel which receives requests to query the internal
// state of the funding manager.
queries chan interface{}
// fundingRequests is a channel used to receive channel initiation
// requests from a local subsystem within the daemon.
fundingRequests chan *initFundingMsg
// newChanBarriers is a map from a channel ID to a 'barrier' which will
// be signalled once the channel is fully open. This barrier acts as a
// synchronization point for any incoming/outgoing HTLCs before the
// channel has been fully opened.
barrierMtx sync.RWMutex
newChanBarriers map[lnwire.ChannelID]chan struct{}
quit chan struct{}
wg sync.WaitGroup
}
// newFundingManager creates and initializes a new instance of the
// fundingManager.
func newFundingManager(cfg fundingConfig) (*fundingManager, error) {
return &fundingManager{
cfg: &cfg,
chanIDKey: cfg.TempChanIDSeed,
activeReservations: make(map[serializedPubKey]pendingChannels),
newChanBarriers: make(map[lnwire.ChannelID]chan struct{}),
fundingMsgs: make(chan interface{}, msgBufferSize),
fundingRequests: make(chan *initFundingMsg, msgBufferSize),
queries: make(chan interface{}, 1),
quit: make(chan struct{}),
}, nil
}
// Start launches all helper goroutines required for handling requests sent
// to the funding manager.
func (f *fundingManager) Start() error {
if atomic.AddInt32(&f.started, 1) != 1 { // TODO(roasbeef): CAS instead
return nil
}
fndgLog.Tracef("Funding manager running")
// Upon restart, the Funding Manager will check the database to load any
// channels that were waiting for their funding transactions to be
// confirmed on the blockchain at the time when the daemon last went
// down.
// TODO(roasbeef): store height that funding finished?
// * would then replace call below
pendingChannels, err := f.cfg.Wallet.ChannelDB.FetchPendingChannels()
if err != nil {
return err
}
_, currentHeight, err := f.cfg.ChainIO.GetBestBlock()
if err != nil {
return err
}
// For any channels that were in a pending state when the daemon was
// last connected, the Funding Manager will re-initialize the channel
// barriers and will also launch waitForFundingConfirmation to wait for
// the channel's funding transaction to be confirmed on the blockchain.
for _, channel := range pendingChannels {
f.barrierMtx.Lock()
fndgLog.Tracef("Loading pending ChannelPoint(%v), creating chan "+
"barrier", *channel.FundingOutpoint)
chanID := lnwire.NewChanIDFromOutPoint(channel.FundingOutpoint)
f.newChanBarriers[chanID] = make(chan struct{})
f.barrierMtx.Unlock()
doneChan := make(chan struct{})
go f.waitForFundingConfirmation(channel, uint32(currentHeight), doneChan)
}
f.wg.Add(1) // TODO(roasbeef): tune
go f.reservationCoordinator()
return nil
}
// Stop signals all helper goroutines to execute a graceful shutdown. This
// method will block until all goroutines have exited.
func (f *fundingManager) Stop() error {
if atomic.AddInt32(&f.stopped, 1) != 1 {
return nil
}
fndgLog.Infof("Funding manager shutting down")
close(f.quit)
f.wg.Wait()
return nil
}
type numPendingReq struct {
resp chan uint32
err chan error
}
// NumPendingChannels returns the number of pending channels currently
// progressing through the reservation workflow.
func (f *fundingManager) NumPendingChannels() (uint32, error) {
respChan := make(chan uint32, 1)
errChan := make(chan error)
req := &numPendingReq{
resp: respChan,
err: errChan,
}
f.queries <- req
return <-respChan, <-errChan
}
// nextPendingChanID returns the next free pending channel ID to be used to
// identify a particular future channel funding workflow.
func (f *fundingManager) nextPendingChanID() [32]byte {
// Obtain a fresh nonce. We do this by encoding the current nonce
// counter, then incrementing it by one.
f.nonceMtx.Lock()
var nonce [8]byte
binary.LittleEndian.PutUint64(nonce[:], f.chanIDNonce)
f.chanIDNonce++
f.nonceMtx.Unlock()
// We'll generate the next pending channelID by "encrypting" 32-bytes
// of zeroes which'll extract 32 random bytes from our stream cipher.
var (
nextChanID [32]byte
zeroes [32]byte
)
salsa20.XORKeyStream(nextChanID[:], zeroes[:], nonce[:], &f.chanIDKey)
return nextChanID
}
type pendingChannel struct {
identityPub *btcec.PublicKey
channelPoint *wire.OutPoint
capacity btcutil.Amount
localBalance btcutil.Amount
remoteBalance btcutil.Amount
}
type pendingChansReq struct {
resp chan []*pendingChannel
err chan error
}
// PendingChannels returns a slice describing all the channels which are
// currently pending at the last state of the funding workflow.
func (f *fundingManager) PendingChannels() ([]*pendingChannel, error) {
respChan := make(chan []*pendingChannel, 1)
errChan := make(chan error)
req := &pendingChansReq{
resp: respChan,
err: errChan,
}
f.queries <- req
return <-respChan, <-errChan
}
// reservationCoordinator is the primary goroutine tasked with progressing the
// funding workflow between the wallet, and any outside peers or local callers.
//
// NOTE: This MUST be run as a goroutine.
func (f *fundingManager) reservationCoordinator() {
defer f.wg.Done()
for {
select {
case msg := <-f.fundingMsgs:
switch fmsg := msg.(type) {
case *fundingRequestMsg:
f.handleFundingRequest(fmsg)
case *fundingResponseMsg:
f.handleFundingResponse(fmsg)
case *fundingCompleteMsg:
f.handleFundingComplete(fmsg)
case *fundingSignCompleteMsg:
f.handleFundingSignComplete(fmsg)
case *fundingLockedMsg:
f.handleFundingLocked(fmsg)
case *fundingErrorMsg:
f.handleErrorMsg(fmsg)
}
case req := <-f.fundingRequests:
f.handleInitFundingMsg(req)
case req := <-f.queries:
switch msg := req.(type) {
case *numPendingReq:
f.handleNumPending(msg)
case *pendingChansReq:
f.handlePendingChannels(msg)
}
case <-f.quit:
return
}
}
}
// handleNumPending handles a request for the total number of pending channels.
func (f *fundingManager) handleNumPending(msg *numPendingReq) {
// TODO(roasbeef): remove this method?
dbPendingChannels, err := f.cfg.Wallet.ChannelDB.FetchPendingChannels()
if err != nil {
close(msg.resp)
msg.err <- err
return
}
msg.resp <- uint32(len(dbPendingChannels))
msg.err <- nil
}
// handlePendingChannels responds to a request for details concerning all
// currently pending channels waiting for the final phase of the funding
// workflow (funding txn confirmation).
func (f *fundingManager) handlePendingChannels(msg *pendingChansReq) {
var pendingChannels []*pendingChannel
dbPendingChannels, err := f.cfg.Wallet.ChannelDB.FetchPendingChannels()
if err != nil {
msg.resp <- nil
msg.err <- err
return
}
for _, dbPendingChan := range dbPendingChannels {
pendingChan := &pendingChannel{
identityPub: dbPendingChan.IdentityPub,
channelPoint: dbPendingChan.ChanID,
capacity: dbPendingChan.Capacity,
localBalance: dbPendingChan.OurBalance,
remoteBalance: dbPendingChan.TheirBalance,
}
pendingChannels = append(pendingChannels, pendingChan)
}
msg.resp <- pendingChannels
msg.err <- nil
}
// processFundingRequest sends a message to the fundingManager allowing it to
// initiate the new funding workflow with the source peer.
func (f *fundingManager) processFundingRequest(msg *lnwire.SingleFundingRequest,
peerAddress *lnwire.NetAddress) {
f.fundingMsgs <- &fundingRequestMsg{msg, peerAddress}
}
// handleFundingRequest creates an initial 'ChannelReservation' within
// the wallet, then responds to the source peer with a single funder response
// message progressing the funding workflow.
// TODO(roasbeef): add error chan to all, let channelManager handle
// error+propagate
func (f *fundingManager) handleFundingRequest(fmsg *fundingRequestMsg) {
// Check number of pending channels to be smaller than maximum allowed
// number and send ErrorGeneric to remote peer if condition is violated.
peerIDKey := newSerializedKey(fmsg.peerAddress.IdentityKey)
if len(f.activeReservations[peerIDKey]) >= cfg.MaxPendingChannels {
errMsg := &lnwire.Error{
ChanID: fmsg.msg.PendingChannelID,
Code: lnwire.ErrMaxPendingChannels,
Data: []byte("Number of pending channels exceed maximum"),
}
if err := f.cfg.SendToPeer(fmsg.peerAddress.IdentityKey, errMsg); err != nil {
fndgLog.Errorf("unable to send max pending channels "+
"message to peer: %v", err)
return
}
return
}
// We'll also reject any requests to create channels until we're fully
// synced to the network as we won't be able to properly validate the
// confirmation of the funding transaction.
isSynced, err := f.cfg.Wallet.IsSynced()
if err != nil {
fndgLog.Errorf("unable to query wallet: %v", err)
return
}
if !isSynced {
errMsg := &lnwire.Error{
ChanID: fmsg.msg.PendingChannelID,
Code: lnwire.ErrSynchronizingChain,
Data: []byte("Synchronizing blockchain"),
}
if err := f.cfg.SendToPeer(fmsg.peerAddress.IdentityKey, errMsg); err != nil {
fndgLog.Errorf("unable to send error message to peer %v", err)
return
}
return
}
msg := fmsg.msg
amt := msg.FundingAmount
delay := msg.CsvDelay
// TODO(roasbeef): error if funding flow already ongoing
fndgLog.Infof("Recv'd fundingRequest(amt=%v, push=%v, delay=%v, pendingId=%x) "+
"from peer(%x)", amt, msg.PushSatoshis, delay, msg.PendingChannelID,
fmsg.peerAddress.IdentityKey.SerializeCompressed())
// TODO(roasbeef): dust limit should be made parameter into funding mgr
// * will change on a per-chain basis
ourDustLimit := lnwallet.DefaultDustLimit()
theirDustlimit := msg.DustLimit
// Attempt to initialize a reservation within the wallet. If the wallet
// has insufficient resources to create the channel, then the
// reservation attempt may be rejected. Note that since we're on the
// responding side of a single funder workflow, we don't commit any
// funds to the channel ourselves.
// TODO(roasbeef): assuming this was an inbound connection, replace
// port with default advertised port
reservation, err := f.cfg.Wallet.InitChannelReservation(amt, 0,
fmsg.peerAddress.IdentityKey, fmsg.peerAddress.Address,
uint16(fmsg.msg.ConfirmationDepth), delay, ourDustLimit,
msg.PushSatoshis, msg.FeePerKw)
if err != nil {
// TODO(roasbeef): push ErrorGeneric message
fndgLog.Errorf("Unable to initialize reservation: %v", err)
return
}
reservation.SetTheirDustLimit(theirDustlimit)
// Once the reservation has been created successfully, we add it to
// this peers map of pending reservations to track this particular
// reservation until either abort or completion.
f.resMtx.Lock()
if _, ok := f.activeReservations[peerIDKey]; !ok {
f.activeReservations[peerIDKey] = make(pendingChannels)
}
f.activeReservations[peerIDKey][msg.PendingChannelID] = &reservationWithCtx{
reservation: reservation,
err: make(chan error, 1),
peerAddress: fmsg.peerAddress,
}
f.resMtx.Unlock()
cancelReservation := func() {
_, err := f.cancelReservationCtx(fmsg.peerAddress.IdentityKey,
msg.PendingChannelID)
if err != nil {
fndgLog.Errorf("unable to cancel reservation: %v", err)
}
}
// With our portion of the reservation initialized, process the
// initiators contribution to the channel.
_, addrs, _, err := txscript.ExtractPkScriptAddrs(msg.DeliveryPkScript,
activeNetParams.Params)
if err != nil {
fndgLog.Errorf("Unable to extract addresses from script: %v", err)
cancelReservation()
return
}
contribution := &lnwallet.ChannelContribution{
FundingAmount: amt,
MultiSigKey: copyPubKey(msg.ChannelDerivationPoint),
CommitKey: copyPubKey(msg.CommitmentKey),
DeliveryAddress: addrs[0],
DustLimit: msg.DustLimit,
CsvDelay: delay,
}
if err := reservation.ProcessSingleContribution(contribution); err != nil {
fndgLog.Errorf("unable to add contribution reservation: %v", err)
cancelReservation()
return
}
fndgLog.Infof("Sending fundingResp for pendingID(%x)",
msg.PendingChannelID)
// With the initiator's contribution recorded, respond with our
// contribution in the next message of the workflow.
ourContribution := reservation.OurContribution()
deliveryScript, err := txscript.PayToAddrScript(ourContribution.DeliveryAddress)
if err != nil {
fndgLog.Errorf("unable to convert address to pkscript: %v", err)
cancelReservation()
return
}
fundingResp := lnwire.NewSingleFundingResponse(msg.PendingChannelID,
ourContribution.RevocationKey, ourContribution.CommitKey,
ourContribution.MultiSigKey, ourContribution.CsvDelay,
deliveryScript, ourDustLimit, msg.ConfirmationDepth)
if err := f.cfg.SendToPeer(fmsg.peerAddress.IdentityKey, fundingResp); err != nil {
fndgLog.Errorf("unable to send funding response to peer: %v", err)
cancelReservation()
return
}
}
// processFundingRequest sends a message to the fundingManager allowing it to
// continue the second phase of a funding workflow with the target peer.
func (f *fundingManager) processFundingResponse(msg *lnwire.SingleFundingResponse,
peerAddress *lnwire.NetAddress) {
f.fundingMsgs <- &fundingResponseMsg{msg, peerAddress}
}
// handleFundingResponse processes a response to the workflow initiation sent
// by the remote peer. This message then queues a message with the funding
// outpoint, and a commitment signature to the remote peer.
func (f *fundingManager) handleFundingResponse(fmsg *fundingResponseMsg) {
msg := fmsg.msg
pendingChanID := fmsg.msg.PendingChannelID
peerKey := fmsg.peerAddress.IdentityKey
resCtx, err := f.getReservationCtx(peerKey, pendingChanID)
if err != nil {
fndgLog.Warnf("Can't find reservation (peerKey:%v, chanID:%v)",
peerKey, pendingChanID)
return
}
cancelReservation := func() {
_, err := f.cancelReservationCtx(peerKey, pendingChanID)
if err != nil {
fndgLog.Errorf("unable to cancel reservation: %v", err)
}
}
fndgLog.Infof("Recv'd fundingResponse for pendingID(%x)", pendingChanID)
resCtx.reservation.SetTheirDustLimit(msg.DustLimit)
// The remote node has responded with their portion of the channel
// contribution. At this point, we can process their contribution which
// allows us to construct and sign both the commitment transaction, and
// the funding transaction.
_, addrs, _, err := txscript.ExtractPkScriptAddrs(msg.DeliveryPkScript,
activeNetParams.Params)
if err != nil {
fndgLog.Errorf("Unable to extract addresses from script: %v", err)
cancelReservation()
resCtx.err <- err
return
}
contribution := &lnwallet.ChannelContribution{
FundingAmount: 0,
MultiSigKey: copyPubKey(msg.ChannelDerivationPoint),
CommitKey: copyPubKey(msg.CommitmentKey),
DeliveryAddress: addrs[0],
RevocationKey: copyPubKey(msg.RevocationKey),
DustLimit: msg.DustLimit,
CsvDelay: msg.CsvDelay,
}
if err := resCtx.reservation.ProcessContribution(contribution); err != nil {
fndgLog.Errorf("Unable to process contribution from %v: %v",
fmsg.peerAddress.IdentityKey, err)
cancelReservation()
resCtx.err <- err
return
}
// Now that we have their contribution, we can extract, then send over
// both the funding out point and our signature for their version of
// the commitment transaction to the remote peer.
outPoint := resCtx.reservation.FundingOutpoint()
_, sig := resCtx.reservation.OurSignatures()
commitSig, err := btcec.ParseSignature(sig, btcec.S256())
if err != nil {
fndgLog.Errorf("Unable to parse signature: %v", err)
cancelReservation()
resCtx.err <- err
return
}
// A new channel has almost finished the funding process. In order to
// properly synchronize with the writeHandler goroutine, we add a new
// channel to the barriers map which will be closed once the channel is
// fully open.
f.barrierMtx.Lock()
channelID := lnwire.NewChanIDFromOutPoint(outPoint)
fndgLog.Debugf("Creating chan barrier for ChanID(%v)", channelID)
f.newChanBarriers[channelID] = make(chan struct{})
f.barrierMtx.Unlock()
fndgLog.Infof("Generated ChannelPoint(%v) for pendingID(%x)", outPoint,
pendingChanID)
revocationKey := resCtx.reservation.OurContribution().RevocationKey
obsfucator := resCtx.reservation.StateNumObfuscator()
fundingComplete := lnwire.NewSingleFundingComplete(pendingChanID, *outPoint,
commitSig, revocationKey, obsfucator)
err = f.cfg.SendToPeer(fmsg.peerAddress.IdentityKey, fundingComplete)
if err != nil {
fndgLog.Errorf("Unable to send funding complete message: %v", err)
cancelReservation()
resCtx.err <- err
return
}
}
// processFundingComplete queues a funding complete message coupled with the
// source peer to the fundingManager.
func (f *fundingManager) processFundingComplete(msg *lnwire.SingleFundingComplete,
peerAddress *lnwire.NetAddress) {
f.fundingMsgs <- &fundingCompleteMsg{msg, peerAddress}
}
// handleFundingComplete progresses the funding workflow when the daemon is on
// the responding side of a single funder workflow. Once this message has been
// processed, a signature is sent to the remote peer allowing it to broadcast
// the funding transaction, progressing the workflow into the final stage.
func (f *fundingManager) handleFundingComplete(fmsg *fundingCompleteMsg) {
peerKey := fmsg.peerAddress.IdentityKey
pendingChanID := fmsg.msg.PendingChannelID
resCtx, err := f.getReservationCtx(peerKey, pendingChanID)
if err != nil {
fndgLog.Warnf("can't find reservation (peerID:%v, chanID:%v)",
peerKey, pendingChanID)
return
}
cancelReservation := func() {
_, err := f.cancelReservationCtx(peerKey, pendingChanID)
if err != nil {
fndgLog.Errorf("unable to cancel reservation: %v", err)
}
}
// The channel initiator has responded with the funding outpoint of the
// final funding transaction, as well as a signature for our version of
// the commitment transaction. So at this point, we can validate the
// inititator's commitment transaction, then send our own if it's valid.
// TODO(roasbeef): make case (p vs P) consistent throughout
fundingOut := fmsg.msg.FundingOutPoint
fndgLog.Infof("completing pendingID(%x) with ChannelPoint(%v)",
pendingChanID, fundingOut)
revokeKey := copyPubKey(fmsg.msg.RevocationKey)
obsfucator := fmsg.msg.StateHintObsfucator
commitSig := fmsg.msg.CommitSignature.Serialize()
// With all the necessary data available, attempt to advance the
// funding workflow to the next stage. If this succeeds then the
// funding transaction will broadcast after our next message.
completeChan, err := resCtx.reservation.CompleteReservationSingle(
revokeKey, &fundingOut, commitSig, obsfucator)
if err != nil {
// TODO(roasbeef): better error logging: peerID, channelID, etc.
fndgLog.Errorf("unable to complete single reservation: %v", err)
cancelReservation()
return
}
// With their signature for our version of the commitment transaction
// verified, we can now send over our signature to the remote peer.
// TODO(roasbeef): just have raw bytes in wire msg? avoids decoding
// then decoding shortly afterwards.
_, sig := resCtx.reservation.OurSignatures()
ourCommitSig, err := btcec.ParseSignature(sig, btcec.S256())
if err != nil {
fndgLog.Errorf("unable to parse signature: %v", err)
cancelReservation()
return
}
// A new channel has almost finished the funding process. In order to
// properly synchronize with the writeHandler goroutine, we add a new
// channel to the barriers map which will be closed once the channel is
// fully open.
f.barrierMtx.Lock()
channelID := lnwire.NewChanIDFromOutPoint(&fundingOut)
fndgLog.Debugf("Creating chan barrier for ChanID(%v)", channelID)
f.newChanBarriers[channelID] = make(chan struct{})
f.barrierMtx.Unlock()
fndgLog.Infof("sending signComplete for pendingID(%x) over ChannelPoint(%v)",
pendingChanID, fundingOut)
signComplete := lnwire.NewSingleFundingSignComplete(pendingChanID, ourCommitSig)
if err := f.cfg.SendToPeer(peerKey, signComplete); err != nil {
fndgLog.Errorf("unable to send signComplete message: %v", err)
cancelReservation()
return
}
_, bestHeight, err := f.cfg.ChainIO.GetBestBlock()
if err != nil {
fndgLog.Errorf("unable to get best height: %v", err)
}
go func() {
doneChan := make(chan struct{})
go f.waitForFundingConfirmation(completeChan,
uint32(bestHeight), doneChan)
<-doneChan
f.deleteReservationCtx(peerKey, fmsg.msg.PendingChannelID)
}()
}
// processFundingSignComplete sends a single funding sign complete message
// along with the source peer to the funding manager.
func (f *fundingManager) processFundingSignComplete(msg *lnwire.SingleFundingSignComplete,
peerAddress *lnwire.NetAddress) {
f.fundingMsgs <- &fundingSignCompleteMsg{msg, peerAddress}
}
// handleFundingSignComplete processes the final message received in a single
// funder workflow. Once this message is processed, the funding transaction is
// broadcast. Once the funding transaction reaches a sufficient number of
// confirmations, a message is sent to the responding peer along with a compact
// encoding of the location of the channel within the blockchain.
func (f *fundingManager) handleFundingSignComplete(fmsg *fundingSignCompleteMsg) {
chanID := fmsg.msg.PendingChannelID
peerKey := fmsg.peerAddress.IdentityKey
resCtx, err := f.getReservationCtx(peerKey, chanID)
if err != nil {
fndgLog.Warnf("can't find reservation (peerID:%v, chanID:%v)",
peerKey, chanID)
return
}
// The remote peer has responded with a signature for our commitment
// transaction. We'll verify the signature for validity, then commit
// the state to disk as we can now open the channel.
commitSig := fmsg.msg.CommitSignature.Serialize()
completeChan, err := resCtx.reservation.CompleteReservation(nil, commitSig)
if err != nil {
fndgLog.Errorf("unable to complete reservation sign complete: %v", err)
resCtx.err <- err
if _, err := f.cancelReservationCtx(peerKey, chanID); err != nil {
fndgLog.Errorf("unable to cancel reservation: %v", err)
}
return
}
fundingPoint := resCtx.reservation.FundingOutpoint()
fndgLog.Infof("Finalizing pendingID(%x) over ChannelPoint(%v), "+
"waiting for channel open on-chain", chanID, fundingPoint)
// Send an update to the upstream client that the negotiation process
// is over.
// TODO(roasbeef): add abstraction over updates to accommodate
// long-polling, or SSE, etc.
resCtx.updates <- &lnrpc.OpenStatusUpdate{
Update: &lnrpc.OpenStatusUpdate_ChanPending{
ChanPending: &lnrpc.PendingUpdate{
Txid: fundingPoint.Hash[:],
OutputIndex: fundingPoint.Index,
},
},
}
_, bestHeight, err := f.cfg.ChainIO.GetBestBlock()
if err != nil {
fndgLog.Errorf("unable to get best height: %v", err)
}
go func() {
doneChan := make(chan struct{})
go f.waitForFundingConfirmation(completeChan, uint32(bestHeight),
doneChan)
select {
case <-f.quit:
return
case <-doneChan:
}
// Finally give the caller a final update notifying them that
// the channel is now open.
// TODO(roasbeef): only notify after recv of funding locked?
resCtx.updates <- &lnrpc.OpenStatusUpdate{
Update: &lnrpc.OpenStatusUpdate_ChanOpen{
ChanOpen: &lnrpc.ChannelOpenUpdate{
ChannelPoint: &lnrpc.ChannelPoint{
FundingTxid: fundingPoint.Hash[:],
OutputIndex: fundingPoint.Index,
},
},
},
}
f.deleteReservationCtx(peerKey, fmsg.msg.PendingChannelID)
}()
}
// waitForFundingConfirmation handles the final stages of the channel funding
// process once the funding transaction has been broadcast. The primary
// function of waitForFundingConfirmation is to wait for blockchain
// confirmation, and then to notify the other systems that must be notified
// when a channel has become active for lightning transactions.
func (f *fundingManager) waitForFundingConfirmation(completeChan *channeldb.OpenChannel,
bestHeight uint32, doneChan chan struct{}) {
defer close(doneChan)
// Register with the ChainNotifier for a notification once the funding
// transaction reaches `numConfs` confirmations.
txid := completeChan.FundingOutpoint.Hash
numConfs := uint32(completeChan.NumConfsRequired)
confNtfn, err := f.cfg.Notifier.RegisterConfirmationsNtfn(&txid,
numConfs, bestHeight)
if err != nil {
fndgLog.Errorf("Unable to register for confirmation of "+
"ChannelPoint(%v)", completeChan.FundingOutpoint)
return
}
fndgLog.Infof("Waiting for funding tx (%v) to reach %v confirmations",
txid, numConfs)
// Wait until the specified number of confirmations has been reached,
// or the wallet signals a shutdown.
confDetails, ok := <-confNtfn.Confirmed
if !ok {
fndgLog.Warnf("ChainNotifier shutting down, cannot complete "+
"funding flow for ChannelPoint(%v)",
completeChan.FundingOutpoint)
return
}
fundingPoint := *completeChan.FundingOutpoint
chanID := lnwire.NewChanIDFromOutPoint(&fundingPoint)
fndgLog.Infof("ChannelPoint(%v) is now active: ChannelID(%x)",
fundingPoint, chanID)
// Now that the channel has been fully confirmed, we'll mark it as open
// within the database.
completeChan.IsPending = false
err = f.cfg.Wallet.ChannelDB.MarkChannelAsOpen(&fundingPoint,
confDetails.BlockHeight)
if err != nil {
fndgLog.Errorf("error setting channel pending flag to false: "+
"%v", err)
return
}
// With the channel marked open, we'll create the state-machine object
// which wraps the database state.
channel, err := lnwallet.NewLightningChannel(nil, nil,
f.cfg.FeeEstimator, completeChan)
if err != nil {
fndgLog.Errorf("error creating new lightning channel: %v", err)
return
}
// Next, we'll send over the funding locked message which marks that we
// consider the channel open by presenting the remote party with our
// next revocation key. Without the revocation key, the remote party
// will be unable to propose state transitions.
nextRevocation, err := channel.NextRevocationkey()
if err != nil {
fndgLog.Errorf("unable to create next revocation: %v", err)
return
}
fundingLockedMsg := lnwire.NewFundingLocked(chanID, nextRevocation)
f.cfg.SendToPeer(completeChan.IdentityPub, fundingLockedMsg)
// With the block height and the transaction index known, we can
// construct the compact chanID which is used on the network to unique
// identify channels.
shortChanID := lnwire.ShortChannelID{
BlockHeight: confDetails.BlockHeight,
TxIndex: confDetails.TxIndex,
TxPosition: uint16(fundingPoint.Index),
}
fndgLog.Infof("Announcing ChannelPoint(%v), short_chan_id=%v", fundingPoint,
spew.Sdump(shortChanID))
// Register the new link with the L3 routing manager so this new
// channel can be utilized during path finding.
go f.announceChannel(f.cfg.IDKey, completeChan.IdentityPub,
channel.LocalFundingKey, channel.RemoteFundingKey,
shortChanID, chanID)
return
}
// processFundingLocked sends a message to the fundingManager allowing it to finish
// the funding workflow.
func (f *fundingManager) processFundingLocked(msg *lnwire.FundingLocked,
peerAddress *lnwire.NetAddress) {
f.fundingMsgs <- &fundingLockedMsg{msg, peerAddress}
}
// handleFundingLocked finalizes the channel funding process and enables the channel
// to enter normal operating mode.
func (f *fundingManager) handleFundingLocked(fmsg *fundingLockedMsg) {
// First, we'll attempt to locate the channel who's funding workflow is
// being finalized by this message. We got to the database rather than
// our reservation map as we may have restarted, mid funding flow.
chanID := fmsg.msg.ChanID
channel, err := f.cfg.FindChannel(chanID)
if err != nil {
fndgLog.Errorf("Unable to locate ChannelID(%v), cannot complete "+
"funding", chanID)
return
}
// With the channel retrieved, we'll send the breach arbiter the new
// channel so it can watch for attempts to breach the channel's
// contract by the remote
// party.
f.cfg.ArbiterChan <- channel
// Launch a defer so we _ensure_ that the channel barrier is properly
// closed even if the target peer is not longer online at this point.
defer func() {
// Close the active channel barrier signalling the readHandler
// that commitment related modifications to this channel can
// now proceed.
f.barrierMtx.Lock()
fndgLog.Tracef("Closing chan barrier for ChanID(%v)", chanID)
close(f.newChanBarriers[chanID])
delete(f.newChanBarriers, chanID)
f.barrierMtx.Unlock()
}()
// Finally, we'll find the peer that sent us this message so we can
// provide it with the fully initialized channel state.
peer, err := f.cfg.FindPeer(fmsg.peerAddress.IdentityKey)
if err != nil {
fndgLog.Errorf("Unable to find peer: %v", err)
return
}
newChanDone := make(chan struct{})
newChanMsg := &newChannelMsg{
channel: channel,
done: newChanDone,
}
peer.newChannels <- newChanMsg
// We pause here to wait for the peer to recognize the new channel
// before we close the channel barrier corresponding to the channel.
select {
case <-f.quit:
return
case <-newChanDone: // Fallthrough if we're not quitting.
}
}
// channelProof is one half of the proof necessary to create an authenticated
// announcement on the network. The two signatures individually sign a
// statement of the existence of a channel.
type channelProof struct {
nodeSig *btcec.Signature
bitcoinSig *btcec.Signature
}
// chanAnnouncement encapsulates the two authenticated announcements that we
// send out to the network after a new channel has been created locally.
type chanAnnouncement struct {
chanAnn *lnwire.ChannelAnnouncement
chanUpdateAnn *lnwire.ChannelUpdate
chanProof *lnwire.AnnounceSignatures
}
// newChanAnnouncement creates the authenticated channel announcement messages
// required to broadcast a newly created channel to the network. The
// announcement is two part: the first part authenticates the existence of the
// channel and contains four signatures binding the funding pub keys and
// identity pub keys of both parties to the channel, and the second segment is
// authenticated only by us and contains our directional routing policy for the
// channel.
func (f *fundingManager) newChanAnnouncement(localPubKey, remotePubKey *btcec.PublicKey,
localFundingKey, remoteFundingKey *btcec.PublicKey,
shortChanID lnwire.ShortChannelID,
chanID lnwire.ChannelID) (*chanAnnouncement, error) {
// The unconditional section of the announcement is the ShortChannelID
// itself which compactly encodes the location of the funding output
// within the blockchain.
chanAnn := &lnwire.ChannelAnnouncement{
ShortChannelID: shortChanID,
}
// The chanFlags field indicates which directed edge of the channel is
// being updated within the ChannelUpdateAnnouncement announcement
// below. A value of zero means it's the edge of the "first" node and 1
// being the other node.
var chanFlags uint16
// The lexicographical ordering of the two identity public keys of the
// nodes indicates which of the nodes is "first". If our serialized
// identity key is lower than theirs then we're the "first" node and
// second otherwise.
selfBytes := localPubKey.SerializeCompressed()
remoteBytes := remotePubKey.SerializeCompressed()
if bytes.Compare(selfBytes, remoteBytes) == -1 {
chanAnn.NodeID1 = localPubKey
chanAnn.NodeID2 = remotePubKey
chanAnn.BitcoinKey1 = localFundingKey
chanAnn.BitcoinKey2 = remoteFundingKey
// If we're the first node then update the chanFlags to
// indicate the "direction" of the update.
chanFlags = 0
} else {
chanAnn.NodeID1 = remotePubKey
chanAnn.NodeID2 = localPubKey
chanAnn.BitcoinKey1 = remoteFundingKey
chanAnn.BitcoinKey2 = localFundingKey
// If we're the second node then update the chanFlags to
// indicate the "direction" of the update.
chanFlags = 1
}
// TODO(roasbeef): populate proper FeeSchema
chanUpdateAnn := &lnwire.ChannelUpdate{
ShortChannelID: shortChanID,
Timestamp: uint32(time.Now().Unix()),
Flags: chanFlags,
TimeLockDelta: 1,
HtlcMinimumMsat: 0,
FeeBaseMsat: 0,
FeeProportionalMillionths: 0,
}
// With the channel update announcement constructed, we'll generate a
// signature that signs a double-sha digest of the announcement.
// This'll serve to authenticate this announcement and any other future
// updates we may send.
chanUpdateMsg, err := chanUpdateAnn.DataToSign()
if err != nil {
return nil, err
}
chanUpdateAnn.Signature, err = f.cfg.SignMessage(f.cfg.IDKey, chanUpdateMsg)
if err != nil {
return nil, errors.Errorf("unable to generate channel "+
"update announcement signature: %v", err)
}
// The channel existence proofs itself is currently announced in
// distinct message. In order to properly authenticate this message, we
// need two signatures: one under the identity public key used which
// signs the message itself and another signature of the identity
// public key under the funding key itself.
// TODO(roasbeef): need to revisit, ensure signatures are signed
// properly
chanAnnMsg, err := chanAnn.DataToSign()
if err != nil {
return nil, err
}
nodeSig, err := f.cfg.SignMessage(f.cfg.IDKey, chanAnnMsg)
if err != nil {
return nil, errors.Errorf("unable to generate node "+
"signature for channel announcement: %v", err)
}
bitcoinSig, err := f.cfg.SignMessage(localFundingKey, selfBytes)
if err != nil {
return nil, errors.Errorf("unable to generate bitcoin "+
"signature for node public key: %v", err)
}
// Finally, we'll generate the announcement proof which we'll use to
// provide the other side with the necessary signatures required to
// allow them to reconstruct the full channel announcement.
proof := &lnwire.AnnounceSignatures{
ChannelID: chanID,
ShortChannelID: shortChanID,
NodeSignature: nodeSig,
BitcoinSignature: bitcoinSig,
}
return &chanAnnouncement{
chanAnn: chanAnn,
chanUpdateAnn: chanUpdateAnn,
chanProof: proof,
}, nil
}
// announceChannel announces a newly created channel to the rest of the network
// by crafting the two authenticated announcements required for the peers on
// the network to recognize the legitimacy of the channel. The crafted
// announcements are then sent to the channel router to handle broadcasting to
// the network during its next trickle.
func (f *fundingManager) announceChannel(localIDKey, remoteIDKey, localFundingKey,
remoteFundingKey *btcec.PublicKey, shortChanID lnwire.ShortChannelID,
chanID lnwire.ChannelID) {
ann, err := f.newChanAnnouncement(localIDKey, remoteIDKey, localFundingKey,
remoteFundingKey, shortChanID, chanID)
if err != nil {
fndgLog.Errorf("can't generate channel announcement: %v", err)
return
}
f.cfg.SendAnnouncement(ann.chanAnn)
f.cfg.SendAnnouncement(ann.chanUpdateAnn)
f.cfg.SendAnnouncement(ann.chanProof)
}
// initFundingWorkflow sends a message to the funding manager instructing it
// to initiate a single funder workflow with the source peer.
// TODO(roasbeef): re-visit blocking nature..
func (f *fundingManager) initFundingWorkflow(peerAddress *lnwire.NetAddress,
req *openChanReq) {
f.fundingRequests <- &initFundingMsg{
peerAddress: peerAddress,
openChanReq: req,
}
}
// handleInitFundingMsg creates a channel reservation within the daemon's
// wallet, then sends a funding request to the remote peer kicking off the
// funding workflow.
func (f *fundingManager) handleInitFundingMsg(msg *initFundingMsg) {
var (
// TODO(roasbeef): add delay
peerKey = msg.peerAddress.IdentityKey
localAmt = msg.localFundingAmt
remoteAmt = msg.remoteFundingAmt
capacity = localAmt + remoteAmt
numConfs = msg.numConfs
ourDustLimit = lnwallet.DefaultDustLimit()
)
fndgLog.Infof("Initiating fundingRequest(localAmt=%v, remoteAmt=%v, "+
"capacity=%v, numConfs=%v, addr=%v, dustLimit=%v)", localAmt,
msg.pushAmt, capacity, numConfs, msg.peerAddress.Address,
ourDustLimit)
// First, we'll query the fee estimator for a fee that should get the
// commitment transaction into the next block (conf target of 1). We
// target the next block here to ensure that we'll be able to execute a
// timely unilateral channel closure if needed.
// TODO(roasbeef): shouldn't be targeting next block
feePerWeight := btcutil.Amount(f.cfg.FeeEstimator.EstimateFeePerWeight(1))
// The protocol currently operates on the basis of fee-per-kw, so we'll
// multiply the computed sat/weight by 1000 to arrive at fee-per-kw.
feePerKw := feePerWeight * 1000
// Initialize a funding reservation with the local wallet. If the
// wallet doesn't have enough funds to commit to this channel, then
// the request will fail, and be aborted.
reservation, err := f.cfg.Wallet.InitChannelReservation(capacity,
localAmt, peerKey, msg.peerAddress.Address, uint16(numConfs), 4,
ourDustLimit, msg.pushAmt, feePerKw)
if err != nil {
msg.err <- err
return
}
// Obtain a new pending channel ID which is used to track this
// reservation throughout its lifetime.
chanID := f.nextPendingChanID()
fndgLog.Infof("Target sat/kw for pendingID(%x): %v", chanID,
int64(feePerKw))
// If a pending channel map for this peer isn't already created, then
// we create one, ultimately allowing us to track this pending
// reservation within the target peer.
peerIDKey := newSerializedKey(peerKey)
f.resMtx.Lock()
if _, ok := f.activeReservations[peerIDKey]; !ok {
f.activeReservations[peerIDKey] = make(pendingChannels)
}
f.activeReservations[peerIDKey][chanID] = &reservationWithCtx{
reservation: reservation,
peerAddress: msg.peerAddress,
updates: msg.updates,
err: msg.err,
}
f.resMtx.Unlock()
// Once the reservation has been created, and indexed, queue a funding
// request to the remote peer, kicking off the funding workflow.
contribution := reservation.OurContribution()
deliveryScript, err := txscript.PayToAddrScript(contribution.DeliveryAddress)
if err != nil {
fndgLog.Errorf("Unable to convert address to pkscript: %v", err)
msg.err <- err
return
}
fndgLog.Infof("Starting funding workflow with %v for pendingID(%x)",
msg.peerAddress.Address, chanID)
// TODO(roasbeef): add FundingRequestFromContribution func
fundingReq := lnwire.NewSingleFundingRequest(
chanID,
msg.channelType,
msg.coinType,
feePerKw,
capacity,
contribution.CsvDelay,
contribution.CommitKey,
contribution.MultiSigKey,
deliveryScript,
ourDustLimit,
msg.pushAmt,
numConfs,
)
if err := f.cfg.SendToPeer(peerKey, fundingReq); err != nil {
fndgLog.Errorf("Unable to send funding request message: %v", err)
msg.err <- err
return
}
}
// waitUntilChannelOpen is designed to prevent other lnd subsystems from
// sending new update messages to a channel before the channel is fully
// opened.
func (f *fundingManager) waitUntilChannelOpen(targetChan lnwire.ChannelID) {
f.barrierMtx.RLock()
barrier, ok := f.newChanBarriers[targetChan]
f.barrierMtx.RUnlock()
if ok {
fndgLog.Tracef("waiting for chan barrier signal for ChanID(%v)",
targetChan)
select {
case <-barrier:
case <-f.quit: // TODO(roasbeef): add timer?
break
}
fndgLog.Tracef("barrier for ChanID(%v) closed", targetChan)
}
}
// processErrorGeneric sends a message to the fundingManager allowing it to
// process the occurred generic error.
func (f *fundingManager) processFundingError(err *lnwire.Error,
peerAddress *lnwire.NetAddress) {
f.fundingMsgs <- &fundingErrorMsg{err, peerAddress}
}
// handleErrorGenericMsg process the error which was received from remote peer,
// depending on the type of error we should do different clean up steps and
// inform the user about it.
func (f *fundingManager) handleErrorMsg(fmsg *fundingErrorMsg) {
e := fmsg.err
switch e.Code {
case lnwire.ErrMaxPendingChannels:
fallthrough
case lnwire.ErrSynchronizingChain:
peerKey := fmsg.peerAddress.IdentityKey
chanID := fmsg.err.ChanID
ctx, err := f.cancelReservationCtx(peerKey, chanID)
if err != nil {
fndgLog.Warnf("unable to delete reservation: %v", err)
ctx.err <- err
return
}
fndgLog.Errorf("Received funding error from %x: %v",
peerKey.SerializeCompressed(), newLogClosure(func() string {
return spew.Sdump(e)
}),
)
ctx.err <- grpc.Errorf(e.Code.ToGrpcCode(), string(e.Data))
return
default:
fndgLog.Warnf("unknown funding error (%v:%v)", e.Code, e.Data)
}
}
// cancelReservationCtx do all needed work in order to securely cancel the
// reservation.
func (f *fundingManager) cancelReservationCtx(peerKey *btcec.PublicKey,
chanID [32]byte) (*reservationWithCtx, error) {
fndgLog.Infof("Cancelling funding reservation for node_key=%x, "+
"chan_id=%x", peerKey.SerializeCompressed(), chanID)
ctx, err := f.getReservationCtx(peerKey, chanID)
if err != nil {
return nil, errors.Errorf("can't find reservation: %v",
err)
}
if err := ctx.reservation.Cancel(); err != nil {
return nil, errors.Errorf("can't cancel reservation: %v",
err)
}
f.deleteReservationCtx(peerKey, chanID)
return ctx, nil
}
// deleteReservationCtx is needed in order to securely delete the reservation.
func (f *fundingManager) deleteReservationCtx(peerKey *btcec.PublicKey,
chanID [32]byte) {
// TODO(roasbeef): possibly cancel funding barrier in peer's
// channelManager?
peerIDKey := newSerializedKey(peerKey)
f.resMtx.Lock()
delete(f.activeReservations[peerIDKey], chanID)
f.resMtx.Unlock()
}
// getReservationCtx returns the reservation context by peer id and channel id.
func (f *fundingManager) getReservationCtx(peerKey *btcec.PublicKey,
chanID [32]byte) (*reservationWithCtx, error) {
peerIDKey := newSerializedKey(peerKey)
f.resMtx.RLock()
resCtx, ok := f.activeReservations[peerIDKey][chanID]
f.resMtx.RUnlock()
if !ok {
return nil, errors.Errorf("unknown channel (id: %v)", chanID)
}
return resCtx, nil
}
func copyPubKey(pub *btcec.PublicKey) *btcec.PublicKey {
return &btcec.PublicKey{
Curve: btcec.S256(),
X: pub.X,
Y: pub.Y,
}
}