Commit Graph

14 Commits

Author SHA1 Message Date
Olaoluwa Osuntokun
aaa8fa33b1
contractcourt: when creating resolveContract closure don't bind to loop variable
In this commit, we fix a long standing bug where at times a co-op
channel closure wouldn't be properly marked as fully closed in the
database. The culprit was a re-occurring code flaw we've seen many times
in the codebase: a closure variable that closes over a loop iterator
variable. Before this instance, I assumed that this could only pop up
when goroutines bind to the loop iterator within a  closure. However,
this instance is the exact same issue, but within a regular closure that
has _delayed_ execution. As the closure doesn't execute until long after
the loop has finished executing, it may still be holding onto the _last_
item the loop iterator variable was assigned to.

The fix for this issue is very simple: re-assign the channel point
before creating the closure. Without this fix, we would go to call
db.MarkChanFullyClosed on a channel that may not have yet actually be in
the pending close state, causing all executions to fail.

Fixes #1054.
Fixes #1056.
Fixes #1075.
2018-04-12 18:54:33 -07:00
Olaoluwa Osuntokun
7a13378671
channeldb+contractcourt: add additional logging around co-op channel closes 2018-04-12 17:13:37 -07:00
Johan T. Halseth
8e77e1e6eb
lnwallet/channel: add NewLocalForceCloseSummary
This commit renames ForceCloseSummary to LocalForceCloseSummary, and
adds a new method NewLocalForceCloseSummary that can be used to derive a
LocalForceCloseSummary if our commitment transaction gets confirmed
in-chain. It is meant to accompany the NewUnilateralCloseSummary method,
which is used for the same purpose in the event of a remote commitment
being seen in-chain.
2018-04-06 09:46:30 +02:00
Johan T. Halseth
8b02064c7b
multi: provide mempool=true to RegisterSpendNtfn 2018-04-03 11:24:07 +02:00
practicalswift
a93736d21e multi: comprehensive typo fixes across all packages 2018-02-06 19:11:11 -08:00
Olaoluwa Osuntokun
2099d6fa77
contractcourt: ensure we always cancel block epoch notifications after use
In this commit, we fix an existing grouting leak within the contract
court package. If a goroutine dies, but it doesn’t actually cancel the
block epoch notification that it requested, then it’s possible to leak
thousands of gorutines. To remedy this situation, we ensure that we’ll
*always* cancel the epoch notification once the goroutine has exited.
2018-02-05 14:41:08 -08:00
Olaoluwa Osuntokun
5df6704a9c
contractcourt: make synchronous chain watcher notifications optional
In this commit, we modify the way that notifications are dispatched
within the chainWatcher. Before we would *always* wait for an ack back
before we started to clean up he database state. This would at times
lead to deadlocks. To remedy this, we now allow callers to decide if
they want notifications to be sync or not. The only current caller that
requires this is the breach arbiter.
2018-01-22 19:19:58 -08:00
Olaoluwa Osuntokun
91d45b37ba
contractcourt: on startup, launch a goroutine to finalize co-op chan close if needed 2018-01-22 19:19:54 -08:00
Olaoluwa Osuntokun
db2b9fd9ff
contractcourt: remove the existing ManuallyResolveChannel methiod
We’re removing this method as it’s no longer needed, since the
chainWatcher will properly handle on-chain co-op closes.
2018-01-22 19:19:54 -08:00
Olaoluwa Osuntokun
bbca53507f
contractcourt: extend the ChainArbitratorConfig with IsOurAddress closure
In this commit, we add the IsOurAddress field into the config of the
chain arb. With this new function closure, the chain arb is able to
detect co-op on chain closes automatically.
2018-01-22 19:19:53 -08:00
Olaoluwa Osuntokun
bdbb33344a
contractcourt: extend resolveContract to also stop any active chainWatcher 2018-01-22 19:19:52 -08:00
Olaoluwa Osuntokun
b5ae0855d2
contractcourt: add new SubscribeChannelEvents method to ChainArbitrator
In this commit, we add a new method to allow external sub-systems to
gain an intent to receive notifications once an on-chain event happens.
This will be used in place of the old channel signals directly on the
channel state machine object in a series of follow up commits.
2018-01-22 19:19:49 -08:00
Olaoluwa Osuntokun
63f7bf4e65
contractcourt: integrate notifications of the chainWatcher with each channel arb
In this commit, we modify the construction of the channel arbitrator to
accept a pointer to an event stream from the chain watcher that’s been
assigned to that channel. As a result, we no longer need a fresh
unilateral close signal, as the one we get from the chain watcher will
*always* be up to date.

For each active channel, we’ll now create a chainWatcher instance that
will be around until the channel is fully closed on chain.
2018-01-22 19:19:48 -08:00
Olaoluwa Osuntokun
31aa7265b7
contractcourt: add new ChainArbitrator struct as central coordinator of package
In this commit, we add the ChainArbitrator struct. The ChainArbitrator
is a special sub-system that will oversee the on-chain resolution of
all active channels, and also channels that are in the pending close
state. The ChainArbitrator maintains a set of ChannelArbitrators, one
for each channel that hasn’t yet been fully resolved.

Outside sub-systems should send new channels to the arbitrator once
they’ve opened. Additionally, they can also trigger manual
interventions to close out a channel on chain forcibly, or just to
signal that a channel has been closed cooperatively.

Finally, (for now) the ChainArbitrator should be notified once a fresh
set of signals for a channel becomes available. The ChannelArbitrator
for the channel will use these set of signals to be notified when an
on-chain event happens.
2018-01-22 19:19:36 -08:00