Commit Graph

3532 Commits

Author SHA1 Message Date
Olaoluwa Osuntokun
723bfb0eac
contractcourt: channel arbitrators now exit on co-op close of the channel 2018-01-22 19:19:52 -08:00
Olaoluwa Osuntokun
62f951a969
contractcourt: extend the chainWatcher to be able to detect co-op closes
In this commit, we extend the chainWatcher to be able to automatically
detect co-op closes of the channel. With this change, it’s now fully
encompassed so able to detect all types of closes on-chain. We detect a
co-op close due to the sequence number being finalized, as well as
paying to us directly in a regular p2wkh-like output.
2018-01-22 19:19:52 -08:00
Olaoluwa Osuntokun
ebb4c84b32
channeldb: add new LatestCommitments and RemoteRevocationStore methods
These methods will allow the chainWatcher to ensure it has the latest
channel state before attempting to construct any resolution objects.
2018-01-22 19:19:51 -08:00
Olaoluwa Osuntokun
239416f242
htlcswitch: update to use new event stream from the chainWatcher 2018-01-22 19:19:51 -08:00
Olaoluwa Osuntokun
69e6ec9954
peer+funding: remove unneeded channel handoff code with the breach arbiter
We no longer need to hand off new channels that come online as the
chainWatcher will be persistent, and always have an active signal for
the entire lifetime of the channel.
2018-01-22 19:19:50 -08:00
Olaoluwa Osuntokun
a0cc1d1b2d
breacharbiter: utilize new channel on-chain event stream to watch for breaches
In this commit, we modify the breach arbiter to no longer require
holding a channel object directly in order to receive new notifications
about possible breaches. Instead, we’ll contact the chain arbiter to
request a new channel event subscription.

As a result of the new architecture, we no longer need to receive a
handoff once the new channel comes online, as the chainWatcher will
always be active and watching the channel until it’s been closed.
2018-01-22 19:19:50 -08:00
Olaoluwa Osuntokun
defa1bc3e3
peer: when creating new links, obtain an on-chain events subscription 2018-01-22 19:19:49 -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
754d1c1c38
contractcourt: when handling a remote force close, use their view of the HTLC's 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
0e14ac2063
contractcourt: add new chainWatcher struct
In this commit, we add a new struct to the package, the chainWatcher.
The duty of this struct is to replace the functionality that was
previously implemented by the closeObserver of each channel. Rather
than the source of notification being tied to the lifetime of a
particular object, it’s now delegated to a persistent object that will
be around for the entire lifetime of the channel (until it’s closed).
This will serve to greatly simplify the code, and eliminate a large
class of bugs.
2018-01-22 19:19:48 -08:00
Olaoluwa Osuntokun
5bbe126c34
lnwallet: add new NewUnilateralCloseSummary function
In this commit, we add a new function that allows a caller to create a
UnilateralCloseSummary with the proper materials. This will be used
within a new sub-system to be added in a later commit to properly
dispatch notifications when on-chain events happen for a channel.
2018-01-22 19:19:47 -08:00
Olaoluwa Osuntokun
341c1678fc
lnwallet: publicly export NewBreachRetribution 2018-01-22 19:19:47 -08:00
Olaoluwa Osuntokun
30c4196f91
lnwallet: remove the closeObserver from the channel state machine
In this PR, we entirely remove the closeObserver from the channel state
machine. It was added very early on before most of the other aspects of
the daemon were built out. This goroutine was responsible for
dispatching notifications to outside parties if the commitment
transaction was spent at all. This had several issues, since it was
linked to the *lifetime* of the channel state machine itself. As a
result of this linkage, we had to do weird stuff like hand off in
memory pointers to the state machine in order to ensure notifications
were properly dispatched.
2018-01-22 19:19:47 -08:00
Olaoluwa Osuntokun
b391049e49
lnd+test: update unit tests to account for recent API changes 2018-01-22 19:19:46 -08:00
Olaoluwa Osuntokun
5758a4e1af
nursery_store: reject duplicate registrations for an output 2018-01-22 19:19:46 -08:00
Olaoluwa Osuntokun
fc8a6568c9
nursery_store: detect Late Registrations when promoting to kindergarten
In this commit, we aim to address a lingering bug caused by a Late
Registration of a kid output from preschool to kindergarten. In this
scenario, an output is promoted, but *after* it’s target maturity
period, meaning that we won’t graduate the output until we restart. To
avoid this, we’ll now detect this case, and bump the graduation height
by one to ensure that when the new block arrives, we properly handle
the output.
2018-01-22 19:19:45 -08:00
Olaoluwa Osuntokun
d0f8b5f194
nursery_store: update IncubateOutputs to take a slice of kid outputs 2018-01-22 19:19:45 -08:00
Olaoluwa Osuntokun
2283960000
utxonursery: update output sweeping to be aware of new output types
In this commit, we modify the logic surrounding sweeping outputs to be
aware of the new types of outputs that the nursery is now responsible
for. Namely: incoming HTLC’s on our commitment transaction as well as
outgoing HTLC’s on the commitment transaction for the remote party. For
 the latter class of HTLC, we’ll now set the lock time on the sweeping
transaction in order to satisfy the CLTV clause in the output we’re
spending.
2018-01-22 19:19:44 -08:00
Olaoluwa Osuntokun
fb17f3aeb4
utxonursery: attempt to republish crib transaction on regraduation 2018-01-22 19:19:44 -08:00
Olaoluwa Osuntokun
12babb3cea
utxonursery: update NurseryReport with details of new output types
The utxo nursery is now responsible for two additional output types:
outgoing HTLC’s on the commitment transaction of the remote party, and
second-level claim transactions that we broadcast. In this commit,
we’ve updated the NurseryReport to now include details, so users are
able to properly keep track of the status of all their pending coins.
2018-01-22 19:19:44 -08:00
Olaoluwa Osuntokun
13b5019cc6
utxonursery: add new absoluteMaturity field to kid outputs
This new field is reserved for outgoing HTLC outputs on the commitment
transaction of the remote party. These outputs don’t have a CSV delay,
but instead have an absolute maturity time.
2018-01-22 19:19:43 -08:00
Olaoluwa Osuntokun
eeb6ab0b17
utxonursery: don't mark channel as fully closed in closeAndRemoveIfMature
The ChannelArbitrator for this channel will do this, so we don’t need
to do it at this point any longer.
2018-01-22 19:19:43 -08:00
Olaoluwa Osuntokun
6568330355
utxonursery: modify IncubateOutputs to accept each output type individually
In this commit, rather than the IncubateOutputs method taking a close
summary entirely, we now take resolutions for each possible output
type. We do this as it’s possible that each output is sent for
incubation at a different time as on-chain conditions change.
Additionally, if we get a baby output (CLTV locked transaction), we’ll
check to see if we can immediately broadcast it. Otherwise, we may
never sweep it unless a restart is attempted.
2018-01-22 19:19:43 -08:00
Olaoluwa Osuntokun
e884da4f03
utxonursery: within IncubateOutputs, don't mark channel as fully closed
We no longer need to mark the channel as fully closed as the
ChannelArbitrator for the channel that incubation was requested for
will handle this.
2018-01-22 19:19:42 -08:00
Olaoluwa Osuntokun
24a16b4f49
lnd: properly initialize entities of new contractcourt package 2018-01-22 19:19:42 -08:00
Olaoluwa Osuntokun
bfbec1c5d3
rpc: properly pass through the FinalCltvDelta param from the proto 2018-01-22 19:19:42 -08:00
Olaoluwa Osuntokun
5b4b6f9c0e
lnrpc: add final_cltv_delta as a SendRequest parameter 2018-01-22 19:19:41 -08:00
Olaoluwa Osuntokun
703057c821
htlcswitch: with debughtlc+hodlhtlc mode, skip all HTLC level checks 2018-01-22 19:19:41 -08:00
Olaoluwa Osuntokun
e34850c7af
htlcswitch: update tests to account for new API changes 2018-01-22 19:19:41 -08:00
Olaoluwa Osuntokun
dbe76a1507
htlcswitch: upon restart, examine all active HTLC's, settle those that we can
In this commit, we address a lingering TODO: before this if we had a
set of HTLC’s that we knew the pre-image to on our commitment
transaction after a restart, then we wouldn’t attempt to settle them.
With this new change, we’ll check that we didn’t already retransmit the
settles for them, and check the preimage cache to see if we already
know the preimage. If we do, then we’ll immediately settle them.
2018-01-22 19:19:40 -08:00
Olaoluwa Osuntokun
ca4eb970ec
htlcswitch: move channel re-sync into distinct function 2018-01-22 19:19:40 -08:00
Olaoluwa Osuntokun
2d133acaeb
htlcswitch: after each new state update, notify callers to set of new HTLC's 2018-01-22 19:19:39 -08:00
Olaoluwa Osuntokun
1418d672f9
htlcswitch: notify the ChainArbitrator of fresh signals upon link creation 2018-01-22 19:19:39 -08:00
Olaoluwa Osuntokun
f2642a70db
htlcswitch: once we discover a pre-image, add it to the witness cache
In this commit, we add some additional logic to the case when we
receive a pre-image from an upstream peer. We’ll immediately add it to
the witness cache, as an incoming HTLC might be waiting on-chain to
fully resolve the HTLC with knowledge of the newly discovered
pre-image.
2018-01-22 19:19:39 -08:00
Olaoluwa Osuntokun
9cb3657314
htlcswitch: add new ProcessContractResolution method
In this commit, we add a new method: ProcessContractResolution. This
will be used by entities of the contract court package to notify us
whenever they discover that we can resolve an incoming contract
off-chain after the outgoing contract was fully resolved on-chain.

We’ll take a contractcourt.ResolutionMsg and map it to the proper
internal package so we can fully resolve an active circuit.
2018-01-22 19:19:38 -08:00
Olaoluwa Osuntokun
8807d1d752
fundingmgr: add new function closure to send new channels to the ChainArbitrator 2018-01-22 19:19:38 -08:00
Olaoluwa Osuntokun
3c66d94f87
rpc: route all channel force close requests through the ChainArbitrator 2018-01-22 19:19:38 -08:00
Olaoluwa Osuntokun
884f3459e7
lnd: add new preimageBeacon struct
In this commit, we add the preimageBeacon  which is an implementation
of both the contractcourt.WitnessBeacon and lnwallet.PreimageCache
interfaces. This will be used when closing channels to check to see if
the know the preimage, and also to communicate to any active contract
resolvers once we discover a preimage either on-chain or off-chain.
2018-01-22 19:19:37 -08:00
Olaoluwa Osuntokun
850ff1d970
channeldb: add new WitnessCache structure
In this commit, we add the WitnessCache sub-storage system of the
greater database. The WitnessCache is a persistent cache of all
witnesses we’ve encountered on the network. We’ll use this cache to
share any on-chain discoveries between active channels. Eventually
we’ll also use this to enforce the variant that a preimage is only to
be used ONCE on the network.
2018-01-22 19:19:37 -08:00
Olaoluwa Osuntokun
94504a9d41
breacharbiter: notify the ChainArbitrator of fresh signals for a channel on startup 2018-01-22 19:19:37 -08:00
Olaoluwa Osuntokun
367231320b
breacharbiter: no longer watch for pending close, ChannelArbitrator will
In this commit, we remove all the code win the BreachArbiter that was
dedicated to sweeping output on the remote party’s commitment
transaction, and also responding to unilateral channel closes. We no
longer need to do this, as this is now the duty of the
ChannelArbitrator.
2018-01-22 19:19:36 -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
Olaoluwa Osuntokun
09b6bee8d4
contractcourt: add complete ContractResolver implementations
In this commit, we introduce a new interface, the ContractResolver. The
duty of a ContractResolver is to watch a contract on-chain, for all
possible transitions, and exit finally when the contract has been fully
resolved. Resolvers themselves can be recursive: meaning producing
another resolver to hand off the duties require to fully resolve a
contract.

Each resolver also has a ResolverKit which contains all the function
closures and interfaces that the resolver need to properly do its job.

The 5 types of resolvers are:
  * outgoing HTLC timeout
  * outgoing HTLC contested
  * incoming HTLC know presage
  * incoming HTLC contested (don’t yet know)
  * commitment sweep

In the future, more advanced resolver types can be added as required.
2018-01-22 19:19:36 -08:00
Olaoluwa Osuntokun
701eb9d4f4
contractcourt: add new briefcase.go file to house persistent arbitrator state
In this commit, we add a new file: briefcase.go. The contents of this
file are the ArbitratorLog. This log will be used by the internal state
machine of each Channel Arbitrator to ensure that each state transition
is fully reflected on-disk, to ensure that the state machine is durable
and able to survive restarts.

This commit also adds a new implementation of the ArbitratorLog
interface backed by boltdb.
2018-01-22 19:19:35 -08:00
Olaoluwa Osuntokun
b4fc34a93a
channeldb: add ShortChanID to close channel summary 2018-01-22 19:19:35 -08:00
Olaoluwa Osuntokun
5d7119fe9c
channeldb: expose methods to serialize HTLC's on-disk
These new methods will be used by the contract court package to
properly serialize the state of HTLC’s that have yet to be fully
resolved on-chain.
2018-01-22 19:19:35 -08:00
Olaoluwa Osuntokun
d64ffcb6c8
contractcourt: add new ChannelArbitrator struct
In this commit, we add the primary struct of the package with a full
implementation. The duty of the ChannelArbitrator is to watch the set
of active contracts on a comment transaction and act accordingly if any
of their redemption criteria have been met. Potential criteria include:
an HTLC about to time out, and HTLC about to time out that we know the
preiamge to, or the remote party going to chain (forcing us to resolve
all pending contracts on chain).

The primary goroutine of this struct implements a persistent state
machine in order to ensure that mid contract resolution, we’re able to
properly survive restarts without losing our place, or forgetting about
a pending contract.

A ChannelArbitrator will stay alive until all contracts have been fully
resolved. This means that outside sub-systems no longer need to worry
about remembering to mark a channel as fully resolved, as it’s the job
of the ChannelArbitrator to do this task.
2018-01-22 19:19:34 -08:00
Olaoluwa Osuntokun
71009438b6
contractcourt: create new package, add logger 2018-01-22 19:19:34 -08:00
Olaoluwa Osuntokun
eba6ba0760
routing: properly prune edges that return a FailPermanentChannelFailure
In this commit, we now account for a case where a node sends us a
FailPermanentChannelFailure during a payment attempt. Before this
commit, we wouldn’t properly prune the edge to avoid re-using it. We
remedy this by properly attempting to prune the edge if possible.
Future changes well send a FailPermanentChannelFailure in the case that
we ned to go on-chain for an outgoing HTLC, and cancel back the
incoming HTLC.
2018-01-22 19:19:34 -08:00