This commit exposes the three main parameters that influence mission
control and path finding to the user as command line or config file
flags. It allows for fine-tuning for optimal results.
Previously every payment had its own local mission control state which
was in effect only for that payment. In this commit most of the local
state is removed and payments all tap into the global mission control
probability estimator.
Furthermore the decay time of pruned edges and nodes is extended, so
that observations about the network can better benefit future payment
processes.
Last, the probability function is transformed from a binary output to a
gradual curve, allowing for a better trade off between candidate routes.
This PR replaces the previously used edge and node ignore lists in path
finding by a probability based system. It modifies path finding so that
it not only compares routes on fee and time lock, but also takes route
success probability into account.
Allowing routes to be compared based on success probability is achieved
by introducing a 'virtual' cost of a payment attempt and using that to
translate probability into another cost factor.
This commit is the final step in making the link unaware of invoices. It
now purely offers the htlc to the invoice registry and follows
instructions from the invoice registry about how and when to respond to
the htlc.
The change also fixes a bug where upon restart, hodl htlcs were
subjected to the invoice minimum cltv delta requirement again. If the
block height has increased in the mean while, the htlc would be canceled
back.
Furthermore the invoice registry interaction is aligned between link and
contract resolvers.
This commit splits out several integration tests that will be modified
in a follow up commit to separate files. The current lnd_test.go file is
10k+ loc which makes it harder to handle by tools and it isn't good for
overview either.
This commit isolates preimages of forwarded htlcs from invoice
preimages. The reason to do this is to prevent the incoming contest
resolver from settling exit hop htlcs for which the invoice isn't marked
as settled.
The former tryApplyPreimage function silently ignored invalid preimages.
This could mask potential bugs. This commit makes the logic stricter and
generates an error in case an unexpected mismatch occurs.
New behaviour of the chain notifier to always send the current block
immediately after registration takes away the need to make a separate
GetBestBlock call on ChainIO.
Now that the success resolver preimage field is always populated by the
incoming contest resolver, preimage lookups earlier in the
process (channel and channel arbitrator) can mostly be removed.
One of the first things the incoming contest resolver does is checking
if the preimage is available and if it is, convert itself into a success
resolver.
This behaviour makes it unnecessary to already determine earlier in the
process whether an incoming contest or a success resolver is needed.
By having all incoming htlcs go through the incoming contest resolver,
the number of execution paths is reduced and it becomes easier to
ascertain that the implemented logic is correct.
The only functional change in this commit is that a forwarded htlc for
which is the preimage is known, is no longer settled when the htlc is
already expired. Previously a success resolver would be instantiated
directly, skipping the expiry height check.
This created a risk that the success resolver would never finish,
because an expired htlc could already have been swept by the remote
party and there is no detection of this remote spend in the success
resolver currently.
With the new change, the general direction that an expired htlc
shouldn't be settled and instead given up on is implemented more
consistently.
This commit prepares for fixing edges cases related to hodl
invoice on-chain resolution.
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.
The idea of the batch counter is to increase it for commit tx updates,
so that if the commit tx cannot be updated immediately (revocation
window exhausted), the batch ticker makes sure it happens later.
The batch counter was increased for forwarded htlcs, but not for exit hop
resolutions.
This lead to the situation where the commitment tx would not be updated,
even though the htlc was settled locally. When no other changes happen
on the channel, the htlc eventually reaches its expiry and the channel
is force closed.
This commit adds logging of the reason to go to chain for a channel.
This can help users to find out the reason why a channels forced closed.
To get all go to chain reasons, an optimization to break early is
removed. This optimization was not significant, because the normal flow
already examined all htlcs. In the exceptional case where we need to go
to chain, it does not weigh up against logging all go to chain reasons.
This commits exposes the various parameters around going to chain and
accepting htlcs in a clear way.
In addition to this, it reverts those parameters to what they were
before the merge of commit d107627145.
This commit restructures the creation of various tls related object. It
also fixes a bug where wildcard IP addresses where only instantiated for
the main RPC server and not the WalletUnlocker service.
This commit increase the expiry grace delta to a value above the
broadcast delta. This prevents htlcs from being accepted that would
immediately trigger a channel force close.
A correct delta is generated in server.go where there is access to
the broadcast delta and passed via the peer to the links.
Co-authored-by: Jim Posen <jim.posen@gmail.com>
Previously there was no minimum remaining blocks requirement on
forwarded htlcs, which may cause channel arbitrator to force
close the channel directly after forwarding the htlc.
Co-authored-by: Jim Posen <jim.posen@gmail.com>
This commit modifies the invoice registry to handle invoices for which
the preimage is not known yet (hodl invoices). In that case, the
resolution channel passed in from links and resolvers is stored until we
either learn the preimage or want to cancel the htlc.
This commit detaches signaling the invoice registry that an htlc was
locked in from the actually settling of the htlc.
It is a preparation for hodl invoices.
In further commits the behaviour of invoice registry becomes more
intrinsically connected to the link. This commit prepares for that by
allowing link and registry to be tested as a single unit.
In the TestChannelLinkMultiHopUnknownPaymentHash test, a preimage was
modified to trigger an unknown payment hash failure. The way the mock is
implemented, it would take the hash of that modified preimage and store
it. It basically stores a completely different invoice. For this test,
it is just as good to store no invoice at all.
Previously it was difficult to use the invoice registry in unit tests,
because it used zpay32 to decode the invoice. For that to succeed, a
valid signature is required on the payment request.
This commit injects the decode dependency on a different level so that
it is easier to mock.
Previously it could happen that an invoice was open at the time of the
LookupInvoice call, the htlc was settled because of that, but when the
SettleInvoice call was made eventually, it would fail because the
invoice was canceled in the mean time. The htlc would then be settled,
but the invoice not marked as such.
Previously a function pointer was passed to chain arbitrator to avoid a
circular dependency. Now that the routetypes package exists, we can pass
the full invoice registry to chain arbitrator.
This is a preparation to be able to use other invoice registry methods
in contract resolvers.
This commit moves the query routes backend logic from the main
rpc server into the sub server. It is another step towards splitting up
the main rpc server code.
In addition to this, a unit test is added to verify rpc parameter
parsing.
Now that QueryRoutes gained the ability to route from any source node
and takes in edge and node black lists, all pieces are in place to have
users implemented their own k-shortests path algorithm. Or any other algorithm
they might wish to use and currently can't.
This commit marks the num_routes field as deprecated as a preparation
for removing k-shortest for lnd.
Joost Jager