This lets us distinguish an critical error from a actual payment result
(success or failure). This is important since we know that we can only
attempt another payment when a final result from the previous payment
attempt is received.
This commit moves the responsibility of generating a unique payment ID
from the switch to the router. This will make it easier for the router
to keep track of which HTLCs were successfully forwarded onto the
network, as it can query the switch for existing HTLCs as long as the
paymentIDs are kept.
The router is expected to maintain a map from paymentHash->paymentID,
such that they can be replayed on restart. This also lets the router
check the status of a sent payment after a restart, by querying the
switch for the paymentID in question.
This commit reevaluates the router's quit channel between each block
during the initial call to syncGraphWithChain, which, in the worst case,
may have to scan several thousand blocks on startup if the node has not
been active for some time. Without this, attempting to stop the daemon
will not exit until the rescan has completed, which for certain backends
could be several hours.
In this commit, we update the process that we use to generate a sphinx
packet to send our onion routed HTLC. Due to recent changes in the
`sphinx` package we use, we now need to use a new PaymentPath struct. As
a result, it no longer makes sense to split up the nodes in a route and
their per hop paylods as they're now in the same struct. All tests have
been updated accordingly.
In this commit, we make our findPath function use an edge's MaxHTLC as
its available bandwidth instead of its Capacity. We do this as it's
possible for the capacity of an edge to not exist when operating as a
light client. For channels that do not support the MaxHTLC optional
field, we'll fall back to using the edge's Capacity.
In this commit, we refactor DeleteChannelEdge to use ChannelIDs rather
than ChannelPoints. We do this as the only use of DeleteChannelEdge is
when we are pruning zombie channels from our graph. When running under a
light client, we are unable to obtain the ChannelPoint of each edge due
to the expensive operations required to do so. As a stop-gap, we'll
resort towards using an edge's ChannelID instead, which is already
gossiped between nodes.
Since light clients no longer have access to an edge's capacity, they
are unable to validate whether the max HTLC value for an updated edge
policy respects the capacity limit. As a stop-gap, we'll skip this
check.
This serves as a stop-gap for light clients as blocks need to be
downloaded from the P2P network, and even with caches, would be too
costly for them to verify. Doing this has two side effects however:
we'll no longer know of the channel capacity and outpoint, which are
essential for some of lnd's responsibilities.
In this commit, we disable attempting to determine when a channel has
been closed out on-chain whenever AssumeChannelValid is active. Since
the flag indicates that performing this operation is expensive, we do
this as a temporary optimization until we can include proofs of channels
being closed in the gossip protocol.
With this change, the only way for channels being removed from the graph
will be once they're considered zombies: which can happen when both
edges of a channel have their disabled bits set or when both edges
haven't had an update within the past two weeks.
To ensure we don't mark an edge as live again just because an update
with a fresh timestamp was received, we'll ensure that we reject any
new updates for zombie channels if they remain disabled when running
with AssumeChannelValid.
In this commit, we add an additional heuristic when running with
AssumeChannelValid. Since AssumeChannelValid being present assumes that
we're not able to quickly determine whether channels are valid, we also
assume that any channels with the disabled bit set on both sides are
considered zombie. This should be relatively safe to do, since the
disabled bits are usually set when the channel is closed on-chain. In
the case that they aren't, we'll have to wait until both edges haven't
had a new update within two weeks to prune them.
We do this to ensure we don't prune too aggressively, as it's possible
that we've only received the channel announcement for a channel, but not
its accompanying channel updates.
This commit removes the QueryRoutes route cache. It is causing wrong
routes to be returned because not all of the request parameters are
stored.
The cache allowed high frequency QueryRoutes calls to the same
destination and with the same amount to be returned fast. This behaviour
can also be achieved by caching the request on the client side. In case
a route is invalidated because of for example a channel update,
the subsequent SendToRoute call will fail. This is a trigger to call
QueryRoutes again for a fresh route.
In this commit, we extend the graph's FetchChannelEdgesByID and
HasChannelEdge methods to also check the zombie index whenever the edge
to be looked up doesn't exist within the edge index. We do this to
signal to callers that the edge is known, but only as a zombie, and the
only information that we have about the edge are the node public keys of
the two parties involved in the edge.
In the event that an edge does exist within the zombie index, we make
an additional check on edge policies to ensure they are not within the
router's pruning window, indicating that it is a fresh update.
In this commit, we update the build to point to the latest version of
neutrino and btcwallet. The latest version of neutrino includes a number
of bug fixes, and new features like reliably transaction broadcast. The
latest version of btcwallet contains a number of bug fixes related to
properly remove invalid transactions from its database.
Currently public keys are represented either as a 33-byte array (Vertex) or as a
btcec.PublicKey struct. The latter isn't useable as index into maps and
cannot be used easily in compares. Therefore the 33-byte array
representation is used predominantly throughout the code base.
This commit converts the argument types of source and target nodes for
path finding to Vertex. Path finding executes no crypto operations and
using Vertex simplifies the code.
Additionally, it prepares for the path finding source parameter to be
exposed over rpc in a follow up commit without requiring conversion back
and forth between Vertex and btcec.PublicKey.
This commit allows the execution of QueryRoutes to be controlled using
lists of black-listed edges and nodes. Any path returned will not pass
through the edges and/or nodes on the list.
In this commit, we update the path finding logic to
ignore a channel if the HTLC value (including the fees
at the point) exceeds the max HTLC value (if set) of the
link.
Since the MaxHTLC field was recently added to the ChannelEdgePolicy struct,
and the Flags field was broken into ChannelFlags and MessageFlags, the
test edge policies should be updated accordingly.
This commit is a step to split the lnwallet package. It puts the Input
interface and implementations in a separate package along with all their
dependencies from lnwallet.
In this commit, we deprecate the `IncorrectHtlcAmount` onion error.
We'll still decode this error to use when retrying paths, but we'll no
longer send this ourselves. The `UnknownPaymentHash` error has been
amended to also include the value of the payment as well. This allows us
to worry about one less error.
In this commit, we ensure that when we update an edge
as a result of a ChannelUpdate being returned from an
onion failure, the max htlc portion of the channel update
is included in the edge update.
In this commit, we alter the ValidateChannelUpdateAnn function in
ann_validation to validate a remote ChannelUpdate's message flags
and max HTLC field. If the message flag is set but the max HTLC
field is not set or vice versa, the ChannelUpdate fails validation.
Co-authored-by: Johan T. Halseth <johanth@gmail.com>
In this commit:
* we partition lnwire.ChanUpdateFlag into two (ChanUpdateChanFlags and
ChanUpdateMsgFlags), from a uint16 to a pair of uint8's
* we rename the ChannelUpdate.Flags to ChannelFlags and add an
additional MessageFlags field, which will be used to indicate the
presence of the optional field HtlcMaximumMsat within the ChannelUpdate.
* we partition ChannelEdgePolicy.Flags into message and channel flags.
This change corresponds to the partitioning of the ChannelUpdate's Flags
field into MessageFlags and ChannelFlags.
Co-authored-by: Johan T. Halseth <johanth@gmail.com>
In this commit we introduce pruning of channel edges instead of channels.
Channel failures apply to a single direction and it is unnecessarily
restricting to prune both directions.
Hop maps were used in a test to verify the population of the hop map
itself and further only in a single function (getFailedChannelID).
Rewrote that function and removed the hop maps completely.
There is the general assumption that channel edge policy nodes are
ordered such that the node1 pubkey is smaller than the key of node 2. In
the test graph, this assumption didn't hold. This commit fixes the test
graph and also adds a check to prevent this from happening again.
This commit adds a new test that checks that the bandwidth hints are
considered correclty for local channels, and that disable flags are
ignored in this case.
To decouple our own path finding from the graph state, we don't consider
the disable bit when attempting to use local channels. Instead the
bandwidth hints will be zero for local inactive channels.
We alos modify the unit test to check that the disable flag is ignored
for local edges.
Fixes the following issues:
- If the channel update of FailFeeInsufficient contains an invalid channel
update, it is not possible to properly add to the failed channels set.
- FailAmountBelowMinimum may apply a channel update, but does not retry.
- FailIncorrectCltvExpiry immediately prunes the vertex without
trying one more time.
In this commit, the logic for all three policy related errors is
aligned.
In this commit we add a check to HtlcSatifiesPolicy to verify that the
time lock for the outgoing htlc that is requested in the onion packet
isn't too far in the future.
Without this check, anyone could force an unreasonably long time lock on
the forwarding node.
In this commit the dependency of unmarshallRoute on edge policies being
available is removed. Edge policies may be unknown and reported as nil.
SendToRoute does not need the policies, but it does need pubkeys of the
route hops. In this commit, unmarshallRoute is modified so that it
takes the pubkeys from edgeInfo instead of channelEdgePolicy.
In addition to this, the route structure is simplified. No more connection
to the database at that point. Fees are determined based on incoming and
outgoing amounts.
Previously, gossiper was the only object that validated channel
updates. Because updates can also be received as part of a
failed payment session in the routing package, validation logic
needs to be available there too. Gossiper already depends on
routing and having routing call the validation logic inside
gossiper would be a circular dependency. Therefore the validation
was moved to routing.
