Merge pull request #790 from halseth/wire-error-handoff

Wire error handoff

fundingmanager.go

@@ -855,12 +855,15 @@ func (f *fundingManager) handleFundingOpen(fmsg *fundingOpenMsg) {
 
 	// TODO(roasbeef): modify to only accept a _single_ pending channel per
 	// block unless white listed
+	f.resMtx.RLock()
 	if len(f.activeReservations[peerIDKey]) >= cfg.MaxPendingChannels {
+		f.resMtx.RUnlock()
 		f.failFundingFlow(
 			fmsg.peerAddress.IdentityKey, fmsg.msg.PendingChannelID,
 			lnwire.ErrMaxPendingChannels)
 		return
 	}
+	f.resMtx.RUnlock()
 
 	// 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
@@ -2656,6 +2659,22 @@ func (f *fundingManager) getReservationCtx(peerKey *btcec.PublicKey,
 	return resCtx, nil
 }
 
+// IsPendingChannel returns a boolean indicating whether the channel identified
+// by the pendingChanID and given peer is pending, meaning it is in the process
+// of being funded. After the funding transaction has been confirmed, the
+// channel will receive a new, permanent channel ID, and will no longer be
+// considered pending.
+func (f *fundingManager) IsPendingChannel(pendingChanID [32]byte,
+	peerAddress *lnwire.NetAddress) bool {
+
+	peerIDKey := newSerializedKey(peerAddress.IdentityKey)
+	f.resMtx.RLock()
+	_, ok := f.activeReservations[peerIDKey][pendingChanID]
+	f.resMtx.RUnlock()
+
+	return ok
+}
+
 func copyPubKey(pub *btcec.PublicKey) *btcec.PublicKey {
 	return &btcec.PublicKey{
 		Curve: btcec.S256(),

htlcswitch/link.go

@@ -1319,7 +1319,21 @@ func (l *channelLink) handleUpstreamMsg(msg lnwire.Message) {
 			l.fail("error receiving fee update: %v", err)
 			return
 		}
+	case *lnwire.Error:
+		// Error received from remote, MUST fail channel, but should
+		// only print the contents of the error message if all
+		// characters are printable ASCII.
+		errMsg := "non-ascii data"
+		if isASCII(msg.Data) {
+			errMsg = string(msg.Data)
 		}
+		l.fail("ChannelPoint(%v): recieved error from peer: %v",
+			l.channel.ChannelPoint(), errMsg)
+	default:
+		log.Warnf("ChannelPoint(%v): received unknown message of type %T",
+			l.channel.ChannelPoint(), msg)
+	}
+
 }
 
 // ackDownStreamPackets is responsible for removing htlcs from a link's
@@ -2407,3 +2421,16 @@ func (l *channelLink) tracef(format string, a ...interface{}) {
 	msg := fmt.Sprintf(format, a...)
 	log.Tracef("ChannelLink(%s) %s", l.ShortChanID(), msg)
 }
+
+// isASCII is a helper method that checks whether all bytes in `data` would be
+// printable ASCII characters if interpreted as a string.
+func isASCII(data []byte) bool {
+	isASCII := true
+	for _, c := range data {
+		if c < 32 || c > 126 {
+			isASCII = false
+			break
+		}
+	}
+	return isASCII
+}

lnwire/channel_id.go

@@ -24,6 +24,10 @@ const (
 // ChannelID can be calculated by XOR'ing the big-endian serialization of the
 type ChannelID [32]byte
 
+// ConnectionWideID is an all-zero ChannelID, which is used to represent a
+// message intended for all channels to to specific peer.
+var ConnectionWideID = ChannelID{}
+
 // String returns the string representation of the ChannelID. This is just the
 // hex string encoding of the ChannelID itself.
 func (c ChannelID) String() string {

peer.go

@@ -748,8 +748,28 @@ out:
 			}
 
 		case *lnwire.Error:
+			switch {
+
+			// In the case of an all-zero channel ID we want to
+			// forward the error to all channels with this peer.
+			case msg.ChanID == lnwire.ConnectionWideID:
+				for _, chanStream := range chanMsgStreams {
+					chanStream.AddMsg(nextMsg)
+				}
+
+			// If the channel ID for the error message corresponds
+			// to a pending channel, then the funding manager will
+			// handle the error.
+			case p.server.fundingMgr.IsPendingChannel(msg.ChanID, p.addr):
 				p.server.fundingMgr.processFundingError(msg, p.addr)
 
+			// If not we hand the error to the channel link for
+			// this channel.
+			default:
+				isChanUpdate = true
+				targetChan = msg.ChanID
+			}
+
 		// TODO(roasbeef): create ChanUpdater interface for the below
 		case *lnwire.UpdateAddHTLC:
 			isChanUpdate = true