funding: ensure reservation contexts are remove in the case of workflow error

fundingmanager.go

@@ -108,10 +108,18 @@ type pendingChannels map[uint64]*reservationWithCtx
 // initiate new channels.
 type serializedPubKey [33]byte
 
-// FundingConfig defines the configuration for the FundingManager. All elements
+// 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 {
+type fundingConfig struct {
 	// Wallet handles the parts of the funding process that involves moving
 	// funds from on-chain transaction outputs into Lightning channels.
 	Wallet *lnwallet.LightningWallet
@@ -149,7 +157,7 @@ type fundingManager struct {
 
 	// cfg is a copy of the configuration struct that the FundingManager was
 	// initialized with.
-	cfg *FundingConfig
+	cfg *fundingConfig
 
 	// channelReservations is a map which houses the state of all pending
 	// funding workflows.
@@ -176,7 +184,7 @@ type fundingManager struct {
 
 // newFundingManager creates and initializes a new instance of the
 // fundingManager.
-func newFundingManager(cfg FundingConfig) (*fundingManager, error) {
+func newFundingManager(cfg fundingConfig) (*fundingManager, error) {
 	// TODO(roasbeef): remove once we actually sign the funding_locked
 	// stuffs
 	s := "30450221008ce2bc69281ce27da07e6683571319d18e949ddfa2965fb6caa" +
@@ -439,15 +447,24 @@ func (f *fundingManager) handleFundingRequest(fmsg *fundingRequestMsg) {
 	}
 	f.activeReservations[peerIDKey][msg.ChannelID] = &reservationWithCtx{
 		reservation: reservation,
+		err:         make(chan error, 1),
 		peerAddress: fmsg.peerAddress,
 	}
 	f.resMtx.Unlock()
 
+	cancelReservation := func() {
+		_, err := f.cancelReservationCtx(fmsg.peerAddress.IdentityKey, msg.ChannelID)
+		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{
@@ -459,6 +476,7 @@ func (f *fundingManager) handleFundingRequest(fmsg *fundingRequestMsg) {
 	}
 	if err := reservation.ProcessSingleContribution(contribution); err != nil {
 		fndgLog.Errorf("unable to add contribution reservation: %v", err)
+		cancelReservation()
 		return
 	}
 
@@ -470,6 +488,7 @@ func (f *fundingManager) handleFundingRequest(fmsg *fundingRequestMsg) {
 	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.ChannelID,
@@ -479,6 +498,7 @@ func (f *fundingManager) handleFundingRequest(fmsg *fundingRequestMsg) {
 
 	if err := f.cfg.SendToPeer(fmsg.peerAddress.IdentityKey, fundingResp); err != nil {
 		fndgLog.Errorf("unable to send funding response to peer: %v", err)
+		cancelReservation()
 		return
 	}
 }
@@ -505,6 +525,12 @@ func (f *fundingManager) handleFundingResponse(fmsg *fundingResponseMsg) {
 		return
 	}
 
+	cancelReservation := func() {
+		if _, err := f.cancelReservationCtx(peerKey, chanID); err != nil {
+			fndgLog.Errorf("unable to cancel reservation: %v", err)
+		}
+	}
+
 	fndgLog.Infof("Recv'd fundingResponse for pendingID(%v)", msg.ChannelID)
 
 	resCtx.reservation.SetTheirDustLimit(msg.DustLimit)
@@ -517,6 +543,7 @@ func (f *fundingManager) handleFundingResponse(fmsg *fundingResponseMsg) {
 		activeNetParams.Params)
 	if err != nil {
 		fndgLog.Errorf("Unable to extract addresses from script: %v", err)
+		cancelReservation()
 		resCtx.err <- err
 		return
 	}
@@ -531,6 +558,7 @@ func (f *fundingManager) handleFundingResponse(fmsg *fundingResponseMsg) {
 	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
 	}
@@ -543,6 +571,7 @@ func (f *fundingManager) handleFundingResponse(fmsg *fundingResponseMsg) {
 	commitSig, err := btcec.ParseSignature(sig, btcec.S256())
 	if err != nil {
 		fndgLog.Errorf("Unable to parse signature: %v", err)
+		cancelReservation()
 		resCtx.err <- err
 		return
 	}
@@ -552,6 +581,8 @@ func (f *fundingManager) handleFundingResponse(fmsg *fundingResponseMsg) {
 	peer, err := f.cfg.FindPeer(peerKey)
 	if err != nil {
 		fndgLog.Errorf("Error finding peer: %v", err)
+		cancelReservation()
+		resCtx.err <- err
 		return
 	}
 	peer.barrierInits <- *outPoint
@@ -567,6 +598,7 @@ func (f *fundingManager) handleFundingResponse(fmsg *fundingResponseMsg) {
 
 	if err := f.cfg.SendToPeer(fmsg.peerAddress.IdentityKey, fundingComplete); err != nil {
 		fndgLog.Errorf("Unable to send funding complete message: %v", err)
+		cancelReservation()
 		resCtx.err <- err
 		return
 	}
@@ -594,6 +626,12 @@ func (f *fundingManager) handleFundingComplete(fmsg *fundingCompleteMsg) {
 		return
 	}
 
+	cancelReservation := func() {
+		if _, err := f.cancelReservationCtx(peerKey, chanID); 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
@@ -616,6 +654,7 @@ func (f *fundingManager) handleFundingComplete(fmsg *fundingCompleteMsg) {
 	if err != nil {
 		// TODO(roasbeef): better error logging: peerID, channelID, etc.
 		fndgLog.Errorf("unable to complete single reservation: %v", err)
+		cancelReservation()
 		return
 	}
 
@@ -627,6 +666,7 @@ func (f *fundingManager) handleFundingComplete(fmsg *fundingCompleteMsg) {
 	ourCommitSig, err := btcec.ParseSignature(sig, btcec.S256())
 	if err != nil {
 		fndgLog.Errorf("unable to parse signature: %v", err)
+		cancelReservation()
 		return
 	}
 
@@ -635,6 +675,7 @@ func (f *fundingManager) handleFundingComplete(fmsg *fundingCompleteMsg) {
 	peer, err := f.cfg.FindPeer(peerKey)
 	if err != nil {
 		fndgLog.Errorf("Error finding peer: %v", err)
+		cancelReservation()
 		return
 	}
 	peer.barrierInits <- fundingOut
@@ -645,6 +686,7 @@ func (f *fundingManager) handleFundingComplete(fmsg *fundingCompleteMsg) {
 	signComplete := lnwire.NewSingleFundingSignComplete(chanID, ourCommitSig)
 	if err := f.cfg.SendToPeer(peerKey, signComplete); err != nil {
 		fndgLog.Errorf("unable to send signComplete message: %v", err)
+		cancelReservation()
 		return
 	}
 }
@@ -777,6 +819,10 @@ func (f *fundingManager) handleFundingSignComplete(fmsg *fundingSignCompleteMsg)
 	if err := resCtx.reservation.CompleteReservation(nil, commitSig); 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
 	}
 
@@ -801,6 +847,11 @@ func (f *fundingManager) handleFundingSignComplete(fmsg *fundingSignCompleteMsg)
 	// once it reaches a sufficient number of confirmations.
 	// TODO(roasbeef): semaphore to limit active chan open goroutines
 	go func() {
+		// As this is the final step in the life-time of a single
+		// funder channel workflow, ensure that the reservation's state
+		// is cleaned up.
+		defer f.deleteReservationCtx(peerKey, chanID)
+
 		// TODO(roasbeef): need to persist pending broadcast channels,
 		// send chan open proof during scan of blocks mined while down.
 		openChanDetails, err := resCtx.reservation.DispatchChan()
@@ -1009,7 +1060,6 @@ func (f *fundingManager) handleInitFundingMsg(msg *initFundingMsg) {
 		return
 	}
 
-	// TODO(bvu): add comment
 	chanID := peer.fetchNextPendingChanID()
 
 	// If a pending channel map for this peer isn't already created, then
@@ -1087,6 +1137,7 @@ func (f *fundingManager) handleErrorGenericMsg(fmsg *fundingErrorMsg) {
 		ctx, err := f.cancelReservationCtx(peerKey, chanID)
 		if err != nil {
 			fndgLog.Warnf("unable to delete reservation: %v", err)
+			ctx.err <- err
 			return
 		}
 
@@ -1109,6 +1160,9 @@ func (f *fundingManager) handleErrorGenericMsg(fmsg *fundingErrorMsg) {
 func (f *fundingManager) cancelReservationCtx(peerKey *btcec.PublicKey,
 	chanID uint64) (*reservationWithCtx, error) {
 
+	fndgLog.Infof("Cancelling funding reservation for node_key=%x, "+
+		"chan_id=%v", peerKey.SerializeCompressed(), chanID)
+
 	ctx, err := f.getReservationCtx(peerKey, chanID)
 	if err != nil {
 		return nil, errors.Errorf("can't find reservation: %v",
@@ -1116,7 +1170,6 @@ func (f *fundingManager) cancelReservationCtx(peerKey *btcec.PublicKey,
 	}
 
 	if err := ctx.reservation.Cancel(); err != nil {
-		ctx.err <- err
 		return nil, errors.Errorf("can't cancel reservation: %v",
 			err)
 	}
@@ -1158,9 +1211,3 @@ func copyPubKey(pub *btcec.PublicKey) *btcec.PublicKey {
 		Y:     pub.Y,
 	}
 }
-
-func newSerializedKey(pubKey *btcec.PublicKey) serializedPubKey {
-	serializedKey := serializedPubKey{}
-	copy(serializedKey[:33], pubKey.SerializeCompressed()[:])
-	return serializedKey
-}

server.go

@@ -197,7 +197,7 @@ func newServer(listenAddrs []string, notifier chainntnfs.ChainNotifier,
 	s.rpcServer = newRpcServer(s)
 	s.breachArbiter = newBreachArbiter(wallet, chanDB, notifier, s.htlcSwitch)
 
-	s.fundingMgr, err = newFundingManager(FundingConfig{
+	s.fundingMgr, err = newFundingManager(fundingConfig{
 		Wallet:      wallet,
 		ArbiterChan: s.breachArbiter.newContracts,
 		SendToPeer:  s.sendToPeer,