This commit clamps all user-chosen CLTVs in LND to be at least 18, which
is the new conservative value used in the sepc. This minimum is applied
uniformly to forwarding CLTV deltas (via channel updates) as well as
final CLTV deltas for new invoices.
This commit reverts cb4cd49dc8d3b0255afe9ff29af9c46c2dbb2c98 to bring
back the insufficient local balance failure.
Distinguishing betweeen this failure and a regular "no route" failure
prevents meaningless htlcs from being sent out.
Modifies the payment session to launch additional pathfinding attempts
for lower amounts. If a single shot payment isn't possible, the goal is
to try to complete the payment using multiple htlcs. In previous
commits, the payment lifecycle has been prepared to deal with
partial-amount routes returned from the payment session. It will query
for additional shards if needed.
Additionally a new rpc payment parameter is added that controls the
maximum number of shards that will be used for the payment.
With mpp it isn't possible anymore for findPath to determine that there
isn't enough local bandwidth. The full payment amount isn't known at
that point.
In a follow-up, this payment outcome can be reintroduced on a higher
level (payment lifecycle).
The default was increased for the main sendpayment RPC in commit
d3fa9767a9729756bab9b4a1121344b265410b1a. This commit sets the
same default for QueryRoutes, routerrpc.SendPayment and
router.EstimateRouteFee.
Modifies TestMissingFeatureDep and TestDestPaymentAddr to use the test
ctx directly instead of generating a closure and using local state to
modify restrictions.
This commit brings us inline with recent modifications to the spec, that
say we shouldn't pay nodes whose feature vectors signal unknown required
features, and also that we shouldn't route through nodes signaling
unknown required features.
Currently we assert that invoices don't have such features during
decoding, but now that users can specify feature vectors via the rpc
interface, it makes sense to perform this check deeper in call stack.
This will also allow us to remove the check from decoding entirely,
making decodepayreq more useful for debugging.
Also the max hop count check can be removed, because the real bound is
the payload size. By moving the check inside the search loop, we now
also backtrack when we hit the limit.
This commit fixes a potential bug in our test harness, by ensuring that
the constructed node policies are configured _after_ sorting. Currently
the node pubkeys are sorted, but additional parameters (max htlc,
disabled, etc) are applied using the unsorted policies.
Most of the constructors used today use the symmetric channel
constructor, so this shouldn't cause an issue with the majority of our
tests. We recently introduced an asymmetric channel constructor for
which this could have been an issue, however, no known issues were
discovered.
Lastly, we remove the direction from the configuration altogether, and
derive it purely from the final sorting of the pubkeys.
We move up the check for TLV support, since we will later use it to
determine if we can use dependent features, e.g. TLV records and payment
addresses.
This commit creates a wrapper struct, grouping all parameters that
influence the final hop during route construction. This is a preliminary
step for passing in the receiver's invoice feature bits, which will be
used to select an appropriate payment or payload type.
In this commit, we overwrite the final hop's features with either the
destination features or those loaded from the graph fallback. This
ensures that the same features used in pathfinding will be provided to
route construction.
In an earlier commit, we validated the final hop's transitive feature
dependencies, so we also add validation to non-final nodes.
This commit adds an optional PaymentAddr field to the RestrictParams, so
that we can verify the final hop can support it before doing an
expensive round of pathfindig.
In this commit, we fix a bug that prevents us from sending custom
records to nodes that aren't in the graph. Previously we would simply
fail if we were unable to retrieve the node's features.
To remedy, we add the option of supplying the destination's feature bits
into path finding. If present, we will use them directly without
consulting the graph, resolving the original issue. Instead, we will
only consult the graph as a fallback, which will still fail if the node
doesn't exist since the TLV features won't be populated in the empty
feature vector.
Furthermore, this also permits us to provide "virtual features" into the
pathfinding logic, where we make assumptions about what the receiver
supports even if the feature vector isn't actually taken from an
invoice. This can useful in cases like keysend, where we don't have an
invoice, but we can still attempt the payment if we assume the receiver
supports TLV.
This commit allows custom node features to be populated in specific test
instances. For consistency, we auto-populate an empty feature vector for
nodes that have nil feature vectors before writing them to the database.
When the (virtual) payment attempt cost is set to zero, probabilities
are no longer a factor in determining the best route. In case of routes
with equal costs, we'd just go with the first one found. This commit
refines this behavior by picking the route with the highest probability.
So even though probability doesn't affect the route cost, it is still
used as a tie breaker.
With the introduction of the max CLTV limit parameter, nodes are able to
reject HTLCs that exceed it. This should also be applied to path
finding, otherwise HTLCs crafted by the same node that exceed it never
left the switch. This wasn't a big deal since the previous max CLTV
limit was ~5000 blocks. Once it was lowered to 1008, the issue became
more apparent. Therefore, all of our path finding attempts now have a
restriction of said limit in in order to properly carry out HTLCs to the
network.
In this commit, we extend the path finding to be able to recognize when
a node needs the new TLV format, or the legacy format based on the
feature bits they expose. We also extend the `LightningPayment` struct
to allow the caller to specify an arbitrary set of TLV records which can
be used for a number of use-cases including various variants of
spontaneous payments.
