Merge pull request #1350 from cfromknecht/switch-duplicate-links

Switch duplicate links
This commit is contained in:
Olaoluwa Osuntokun 2018-06-10 18:13:26 -07:00 committed by GitHub
commit 2e838abb3f
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2 changed files with 85 additions and 25 deletions

@ -1723,6 +1723,13 @@ func (s *Switch) AddLink(link ChannelLink) error {
chanID := link.ChanID()
// First, ensure that this link is not already active in the switch.
_, err := s.getLink(chanID)
if err == nil {
return fmt.Errorf("unable to add ChannelLink(%v), already "+
"active", chanID)
}
// Get and attach the mailbox for this link, which buffers packets in
// case there packets that we tried to deliver while this link was
// offline.
@ -1772,24 +1779,18 @@ func (s *Switch) addLiveLink(link ChannelLink) {
s.interfaceIndex[peerPub][link] = struct{}{}
}
// removeLiveLink removes a link from all associated forwarding indexes, this
// prevents it from being a candidate in forwarding.
func (s *Switch) removeLiveLink(link ChannelLink) {
// Remove the channel from live link indexes.
delete(s.linkIndex, link.ChanID())
delete(s.forwardingIndex, link.ShortChanID())
// Remove the channel from channel index.
peerPub := link.Peer().PubKey()
delete(s.interfaceIndex, peerPub)
}
// GetLink is used to initiate the handling of the get link command. The
// request will be propagated/handled to/in the main goroutine.
func (s *Switch) GetLink(chanID lnwire.ChannelID) (ChannelLink, error) {
s.indexMtx.RLock()
defer s.indexMtx.RUnlock()
return s.getLink(chanID)
}
// getLink returns the link stored in either the pending index or the live
// lindex.
func (s *Switch) getLink(chanID lnwire.ChannelID) (ChannelLink, error) {
link, ok := s.linkIndex[chanID]
if !ok {
link, ok = s.pendingLinkIndex[chanID]
@ -1829,23 +1830,23 @@ func (s *Switch) RemoveLink(chanID lnwire.ChannelID) error {
func (s *Switch) removeLink(chanID lnwire.ChannelID) error {
log.Infof("Removing channel link with ChannelID(%v)", chanID)
link, ok := s.linkIndex[chanID]
if ok {
s.removeLiveLink(link)
link.Stop()
return nil
link, err := s.getLink(chanID)
if err != nil {
return err
}
link, ok = s.pendingLinkIndex[chanID]
if ok {
delete(s.pendingLinkIndex, chanID)
link.Stop()
// Remove the channel from live link indexes.
delete(s.pendingLinkIndex, link.ChanID())
delete(s.linkIndex, link.ChanID())
delete(s.forwardingIndex, link.ShortChanID())
return nil
}
// Remove the channel from channel index.
peerPub := link.Peer().PubKey()
delete(s.interfaceIndex, peerPub)
return ErrChannelLinkNotFound
link.Stop()
return nil
}
// UpdateShortChanID updates the short chan ID for an existing channel. This is

@ -25,6 +25,65 @@ func genPreimage() ([32]byte, error) {
return preimage, nil
}
// TestSwitchAddDuplicateLink tests that the switch will reject duplicate links
// for both pending and live links. It also tests that we can successfully
// add a link after having removed it.
func TestSwitchAddDuplicateLink(t *testing.T) {
t.Parallel()
alicePeer, err := newMockServer(t, "alice", nil)
if err != nil {
t.Fatalf("unable to create alice server: %v", err)
}
s, err := initSwitchWithDB(nil)
if err != nil {
t.Fatalf("unable to init switch: %v", err)
}
if err := s.Start(); err != nil {
t.Fatalf("unable to start switch: %v", err)
}
defer s.Stop()
chanID1, _, aliceChanID, _ := genIDs()
pendingChanID := lnwire.ShortChannelID{}
aliceChannelLink := newMockChannelLink(
s, chanID1, pendingChanID, alicePeer, false,
)
if err := s.AddLink(aliceChannelLink); err != nil {
t.Fatalf("unable to add alice link: %v", err)
}
// Alice should have a pending link, adding again should fail.
if err := s.AddLink(aliceChannelLink); err == nil {
t.Fatalf("adding duplicate link should have failed")
}
// Update the short chan id of the channel, so that the link goes live.
aliceChannelLink.setLiveShortChanID(aliceChanID)
err = s.UpdateShortChanID(chanID1)
if err != nil {
t.Fatalf("unable to update alice short_chan_id: %v", err)
}
// Alice should have a live link, adding again should fail.
if err := s.AddLink(aliceChannelLink); err == nil {
t.Fatalf("adding duplicate link should have failed")
}
// Remove the live link to ensure the indexes are cleared.
if err := s.RemoveLink(chanID1); err != nil {
t.Fatalf("unable to remove alice link: %v", err)
}
// Alice has no links, adding should succeed.
if err := s.AddLink(aliceChannelLink); err != nil {
t.Fatalf("unable to add alice link: %v", err)
}
}
// TestSwitchSendPending checks the inability of htlc switch to forward adds
// over pending links, and the UpdateShortChanID makes a pending link live.
func TestSwitchSendPending(t *testing.T) {