This commit introduces the requirement specified in BOLT#7,
where we ignore any node announcements for a specific node
if we yet haven't seen any channel announcements where this
node takes part. This is to prevent someone DoS-ing the
network with cheap node announcements. In the router this
is enforced by requiring a call to AddNode(node_id) to
be preceded by an AddEdge(edge_id) call, where node_id is
one of the nodes in edge_id.
Within the network, it's important that when an HTLC forwarding failure
occurs, the recipient is notified in a timely manner in order to ensure
that errors are graceful and not unknown. For that reason with
accordance to BOLT №4 onion failure obfuscation have been added.
This commit modifies the processing in the routing package eo new
announcements. Previously, if we cgot a cnew channel announcement but
didn’t yet know of the verses that the chanell connected, the
cnnounacment would be accepted. This behavior was eronoues as if the
channel were to be queried for, the DB query would fail as we would be
unable to retrieve the two nodes involved int he channel.
To avoid such an error case, we will now _reject_ any channel
announcements in which we don’t yet have a valid node announcement for
the connected nodes. This case has been inserted into the handling of
channel announcement, a new test has been added, and finally older
tests have also been updated to ensure that nodes are added to the
database _before_ the edge is.
This commit modifies the routing package to no longer use the
ChainNotifier for pruning the channel graph. Instead, we now use the
FilteredChainView interface to more (from the ChannelRouter’s PoV)
efficiently maintain the channel graph.
Rather than scanning the _entire_ block manually, we now rely on the
FilteredChainView to provide us with FilteredBlocks which include
_only_ the relevant transactions that we care about.
Originally we adding the edge without proof in order to able to use it
for payments path constrcution. This method will allow us to populate
the announcement proof after the exchange of the half proofs and
constrcutrion of full proof finished.
In this commit the routing package was divided on two separete one,
this was done because 'routing' package start take too much responsibily
on themself, so with following commit:
Routing pacakge:
Enitites:
* channeldb.ChannelEdge
* channeldb.ChannelPolicy
* channeldb.NodeLightning
Responsibilities:
* send topology notification
* find payment paths
* send payment
* apply topology changes to the graph
* prune graph
* validate that funding point exist and corresponds to given one
* to be the source of topology data
Discovery package:
Entities:
* lnwire.AnnounceSignature
* lnwire.ChannelAnnouncement
* lnwire.NodeAnnouncement
* lnwire.ChannelUpdateAnnouncement
Responsibilities:
* validate announcement signatures
* sync topology with newly connected peers
* handle the premature annoucement
* redirect topology changes to the router susbsystem
* broadcast announcement to the rest of the network
* exchange channel announcement proofs
Before that moment all that was in the 'routing' which is quite big for
one subsystem.
split
This commit adds payment route failure fallback to SendPayment. By
this, we mean that we now take all the possible routes found during
path finding and try them in series. Either a route fails and we move
onto the next one, or the route is successful and we terminate early.
With this commit, sending payments using lnd is now much more robust as
if there exists an eligible route with sufficient capacity, it will be
utilized.
This commit modifies the existing FindRoute method on the ChannelRouter
to now use the KSP implementation added in a prior commit.
This new method FindRoutes, is able to find all the possible paths
between a source and destination. The method takes all paths reported
by findPaths, and attempt to turn each of them into a route. A route
differs from a path in that is has complete time-lock and fee
information. Some paths may not be able to be turned into routes as
once fees are accounted for the have an insufficient flow. We then take
the routes, sort them by total fee (with time-lock being a
time-breaker), then return them in sorted order.
