breacharbiter: reliable handoff from wallet
This commit is contained in:
Conner Fromknecht
parent
e2fe4c2955
commit
fb228a0f7d
543
breacharbiter.go
543
breacharbiter.go
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@ -15,33 +15,34 @@ import (
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"github.com/lightningnetwork/lnd/htlcswitch"
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"github.com/lightningnetwork/lnd/lnwallet"
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"github.com/roasbeef/btcd/blockchain"
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"github.com/roasbeef/btcd/btcec"
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"github.com/roasbeef/btcd/chaincfg/chainhash"
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"github.com/roasbeef/btcd/txscript"
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"github.com/roasbeef/btcd/wire"
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"github.com/roasbeef/btcutil"
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)
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// retributionBucket stores retribution state on disk between detecting a
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// contract breach, broadcasting a justice transaction that sweeps the channel,
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// and finally witnessing the justice transaction confirm on the blockchain. It
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// is critical that such state is persisted on disk, so that if our node
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// restarts at any point during the retribution procedure, we can recover and
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// continue from the persisted state.
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var retributionBucket = []byte("retribution")
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var (
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// retributionBucket stores retribution state on disk between detecting
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// a contract breach, broadcasting a justice transaction that sweeps the
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// channel, and finally witnessing the justice transaction confirm on
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// the blockchain. It is critical that such state is persisted on disk,
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// so that if our node restarts at any point during the retribution
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// procedure, we can recover and continue from the persisted state.
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retributionBucket = []byte("retribution")
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// justiceTxnBucket holds the finalized justice transactions for all
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// breached contracts. Entries are added to the justice txn bucket just
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// before broadcasting the sweep txn.
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justiceTxnBucket = []byte("justice-txn")
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)
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// BreachConfig bundles the required subsystems used by the breach arbiter. An
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// instance of BreachConfig is passed to newBreachArbiter during instantiation.
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type BreachConfig struct {
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// ChainIO is used by the breach arbiter to determine the current height
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// of the blockchain, which is required to subscribe for spend
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// notifications from Notifier.
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ChainIO lnwallet.BlockChainIO
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// CloseLink allows the breach arbiter to shutdown any channel links for
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// which it detects a breach, ensuring now further activity will
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// continue across the link. The method accepts link's channel point and a
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// close type to be included in the channel close summary.
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// continue across the link. The method accepts link's channel point and
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// a close type to be included in the channel close summary.
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CloseLink func(*wire.OutPoint, htlcswitch.ChannelCloseType)
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// DB provides access to the user's channels, allowing the breach
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@ -85,6 +86,9 @@ type BreachConfig struct {
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// counterparties.
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// TODO(roasbeef): closures in config for subsystem pointers to decouple?
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type breachArbiter struct {
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started uint32
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stopped uint32
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cfg *BreachConfig
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// breachObservers is a map which tracks all the active breach
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@ -112,10 +116,8 @@ type breachArbiter struct {
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// breach closes.
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settledContracts chan *wire.OutPoint
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started uint32
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stopped uint32
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quit chan struct{}
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wg sync.WaitGroup
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quit chan struct{}
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wg sync.WaitGroup
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}
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// newBreachArbiter creates a new instance of a breachArbiter initialized with
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@ -141,40 +143,52 @@ func (b *breachArbiter) Start() error {
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brarLog.Tracef("Starting breach arbiter")
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// We load all pending retributions from the database and
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// deterministically reconstruct a channel close summary for each. In
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// the event that a channel is still open after being breached, we can
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// use the close summary to reinitiate a channel close so that the
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// breach is reflected in channeldb.
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// Load all retributions currently persisted in the retribution store.
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breachRetInfos := make(map[wire.OutPoint]retributionInfo)
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closeSummaries := make(map[wire.OutPoint]channeldb.ChannelCloseSummary)
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err := b.cfg.Store.ForAll(func(ret *retributionInfo) error {
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// Extract emitted retribution information.
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if err := b.cfg.Store.ForAll(func(ret *retributionInfo) error {
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breachRetInfos[ret.chanPoint] = *ret
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// Deterministically reconstruct channel close summary from
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// persisted retribution information and record in breach close
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// summaries map under the corresponding channel point.
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closeSummary := channeldb.ChannelCloseSummary{
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ChanPoint: ret.chanPoint,
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ClosingTXID: ret.commitHash,
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RemotePub: ret.remoteIdentity,
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Capacity: ret.capacity,
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SettledBalance: ret.settledBalance,
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CloseType: channeldb.BreachClose,
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IsPending: true,
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}
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closeSummaries[ret.chanPoint] = closeSummary
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return nil
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})
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if err != nil {
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}); err != nil {
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return err
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}
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// Load all currently closed channels from disk, we will use the
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// channels that have been marked fully closed to filter the retribution
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// information loaded from disk. This is necessary in the event that the
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// channel was marked fully closed, but was not removed from the
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// retribution store.
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closedChans, err := b.cfg.DB.FetchClosedChannels(false)
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if err != nil {
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brarLog.Errorf("unable to fetch closing channels: %v", err)
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return err
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}
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// Using the set of non-pending, closed channels, reconcile any
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// discrepancies between the channeldb and the retribution store by
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// removing any retribution information for which we have already
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// finished our responsibilities. If the removal is successful, we also
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// remove the entry from our in-memory map, to avoid any further action
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// for this channel.
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for _, chanSummary := range closedChans {
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if chanSummary.IsPending {
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continue
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}
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chanPoint := &chanSummary.ChanPoint
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if _, ok := breachRetInfos[*chanPoint]; ok {
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if err := b.cfg.Store.Remove(chanPoint); err != nil {
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brarLog.Errorf("unable to remove closed "+
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"chanid=%v from breach arbiter: %v",
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chanPoint, err)
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return err
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}
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delete(breachRetInfos, *chanPoint)
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}
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}
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// We need to query that database state for all currently active
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// channels, each of these channels will need a goroutine assigned to
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// it to watch for channel breaches.
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// channels, these channels will represent a super set of all channels
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// that may be assigned a go routine to monitor for channel breaches.
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activeChannels, err := b.cfg.DB.FetchAllChannels()
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if err != nil && err != channeldb.ErrNoActiveChannels {
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brarLog.Errorf("unable to fetch active channels: %v", err)
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@ -188,29 +202,20 @@ func (b *breachArbiter) Start() error {
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}
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// Here we will determine a set of channels that will need to be managed
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// by the contractObserver. For each of the open channels read from
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// disk, we will create a channel state machine that can be used to
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// watch for any potential channel closures. We must first exclude any
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// channel whose retribution process has been initiated, and proceed to
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// mark them as closed. The state machines generated for these filtered
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// channels can be discarded, as their fate will be placed in the hands
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// of an exactRetribution task spawned later.
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//
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// NOTE: Spawning of the exactRetribution task is intentionally
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// postponed until after this step in order to ensure that the all
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// breached channels are reflected as closed in channeldb and consistent
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// with what is checkpointed by the breach arbiter. Instead of treating
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// the breached-and-closed and breached-but-still-active channels as
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// separate sets of channels, we first ensure that all
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// breached-but-still-active channels are promoted to
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// breached-and-closed during restart, allowing us to treat them as a
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// single set from here on out. This approach also has the added benefit
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// of minimizing the likelihood that the wrong number of tasks are
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// spawned per breached channel, and prevents us from being in a
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// position where retribution has completed but the channel is still
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// marked as open in channeldb.
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// by the contractObserver. This should comprise all active channels
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// that have not been breached. If the channel point has an entry in the
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// retribution store, we skip it to avoid creating a breach observer.
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// Resolving breached channels will be handled later by spawning an
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// exactRetribution task for each.
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channelsToWatch := make([]*lnwallet.LightningChannel, 0, nActive)
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for _, chanState := range activeChannels {
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// If this channel was previously breached, we skip it here to
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// avoid creating a breach observer, as we can go straight to
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// the task of exacting retribution.
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if _, ok := breachRetInfos[chanState.FundingOutpoint]; ok {
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continue
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}
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// Initialize active channel from persisted channel state.
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channel, err := lnwallet.NewLightningChannel(nil,
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b.cfg.Notifier, b.cfg.Estimator, chanState)
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@ -220,62 +225,28 @@ func (b *breachArbiter) Start() error {
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return err
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}
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// Before marking this as an active channel that the breach
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// arbiter should watch, check to see if this channel was
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// previously breached. If so, we attempt to reflect this in the
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// channeldb by closing the channel. Upon success, we continue
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// because the channel is no longer open, and thus does not need
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// to be managed by the contractObserver.
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chanPoint := chanState.FundingOutpoint
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if closeSummary, ok := closeSummaries[chanPoint]; ok {
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// Since this channel should not be open, we
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// immediately notify the HTLC switch that this link
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// should be closed, and that all activity on the link
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// should cease.
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b.cfg.CloseLink(&chanState.FundingOutpoint,
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htlcswitch.CloseBreach)
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// Ensure channeldb is consistent with the persisted
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// breach.
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err := channel.DeleteState(&closeSummary)
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if err != nil {
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brarLog.Errorf("unable to delete channel "+
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"state: %v", err)
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return err
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}
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// Now that this channel is both breached _and_ closed,
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// we can skip adding it to the `channelsToWatch` since
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// we can begin the retribution process immediately.
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continue
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}
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// Finally, add this channel to breach arbiter's list of
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// channels to watch.
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channelsToWatch = append(channelsToWatch, channel)
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}
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// TODO(roasbeef): instead use closure height of channel
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_, currentHeight, err := b.cfg.ChainIO.GetBestBlock()
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if err != nil {
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return err
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}
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// Additionally, we'll also want to watch any pending close or force
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// close transactions so we can properly mark them as resolved in the
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// database.
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if err := b.watchForPendingCloseConfs(currentHeight); err != nil {
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if err := b.watchForPendingCloseConfs(); err != nil {
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return err
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}
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// Spawn the exactRetribution tasks to monitor and resolve any breaches
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// that were loaded from the retribution store.
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for chanPoint, closeSummary := range closeSummaries {
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for chanPoint := range breachRetInfos {
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retInfo := breachRetInfos[chanPoint]
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// Register for a notification when the breach transaction is
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// confirmed on chain.
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breachTXID := closeSummary.ClosingTXID
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breachTXID := retInfo.commitHash
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confChan, err := b.cfg.Notifier.RegisterConfirmationsNtfn(
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&breachTXID, 1, uint32(currentHeight))
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&breachTXID, 1, retInfo.breachHeight)
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if err != nil {
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brarLog.Errorf("unable to register for conf updates "+
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"for txid: %v, err: %v", breachTXID, err)
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@ -284,7 +255,6 @@ func (b *breachArbiter) Start() error {
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// Launch a new goroutine which to finalize the channel
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// retribution after the breach transaction confirms.
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retInfo := breachRetInfos[chanPoint]
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b.wg.Add(1)
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go b.exactRetribution(confChan, &retInfo)
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}
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@ -298,12 +268,13 @@ func (b *breachArbiter) Start() error {
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// watchForPendingCloseConfs dispatches confirmation notification subscribers
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// that mark any pending channels as fully closed when signaled.
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func (b *breachArbiter) watchForPendingCloseConfs(currentHeight int32) error {
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func (b *breachArbiter) watchForPendingCloseConfs() error {
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pendingCloseChans, err := b.cfg.DB.FetchClosedChannels(true)
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if err != nil {
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brarLog.Errorf("unable to fetch closing channels: %v", err)
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return err
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}
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for _, pendingClose := range pendingCloseChans {
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// If this channel was force closed, and we have a non-zero
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// time-locked balance, then the utxoNursery is currently
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@ -319,7 +290,7 @@ func (b *breachArbiter) watchForPendingCloseConfs(currentHeight int32) error {
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closeTXID := pendingClose.ClosingTXID
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confNtfn, err := b.cfg.Notifier.RegisterConfirmationsNtfn(
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&closeTXID, 1, uint32(currentHeight))
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&closeTXID, 1, pendingClose.CloseHeight)
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if err != nil {
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return err
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}
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@ -376,6 +347,12 @@ func (b *breachArbiter) Stop() error {
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return nil
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}
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// IsBreached queries the breach arbiter's retribution store to see if it is
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// aware of any channel breaches for a particular channel point.
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func (b *breachArbiter) IsBreached(chanPoint *wire.OutPoint) (bool, error) {
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return b.cfg.Store.IsBreached(chanPoint)
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}
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// contractObserver is the primary goroutine for the breachArbiter. This
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// goroutine is responsible for managing goroutines that watch for breaches for
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// all current active and newly created channels. If a channel breach is
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@ -389,13 +366,16 @@ func (b *breachArbiter) contractObserver(
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defer b.wg.Done()
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brarLog.Infof("Starting contract observer with %v active channels",
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len(activeChannels))
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// For each active channel found within the database, we launch a
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// detected breachObserver goroutine for that channel and also track
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// the new goroutine within the breachObservers map so we can cancel it
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// later if necessary.
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for _, channel := range activeChannels {
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settleSignal := make(chan struct{})
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chanPoint := channel.ChannelPoint()
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chanPoint := channel.ChanPoint
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b.breachObservers[*chanPoint] = settleSignal
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b.wg.Add(1)
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@ -409,12 +389,6 @@ out:
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for {
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select {
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case breachInfo := <-b.breachedContracts:
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_, currentHeight, err := b.cfg.ChainIO.GetBestBlock()
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if err != nil {
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brarLog.Errorf("unable to get best height: %v",
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err)
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}
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// A new channel contract has just been breached! We
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// first register for a notification to be dispatched
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// once the breach transaction (the revoked commitment
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@ -422,7 +396,7 @@ out:
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// ensure we're not dealing with a moving target.
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breachTXID := &breachInfo.commitHash
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cfChan, err := b.cfg.Notifier.RegisterConfirmationsNtfn(
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breachTXID, 1, uint32(currentHeight))
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breachTXID, 1, breachInfo.breachHeight)
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if err != nil {
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brarLog.Errorf("unable to register for conf "+
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"updates for txid: %v, err: %v",
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@ -449,7 +423,7 @@ out:
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// daemon, so we launch a new breachObserver to handle
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// the detection of attempted contract breaches.
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settleSignal := make(chan struct{})
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chanPoint := contract.ChannelPoint()
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chanPoint := contract.ChanPoint
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// If the contract is already being watched, then an
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// additional send indicates we have a stale version of
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@ -516,14 +490,17 @@ func (b *breachArbiter) exactRetribution(
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// TODO(roasbeef): state needs to be checkpointed here
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var breachConfHeight uint32
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select {
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case _, ok := <-confChan.Confirmed:
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case breachConf, ok := <-confChan.Confirmed:
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// If the second value is !ok, then the channel has been closed
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// signifying a daemon shutdown, so we exit.
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if !ok {
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return
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}
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breachConfHeight = breachConf.BlockHeight
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// Otherwise, if this is a real confirmation notification, then
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// we fall through to complete our duty.
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case <-b.quit:
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@ -533,40 +510,55 @@ func (b *breachArbiter) exactRetribution(
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brarLog.Debugf("Breach transaction %v has been confirmed, sweeping "+
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"revoked funds", breachInfo.commitHash)
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// With the breach transaction confirmed, we now create the justice tx
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// which will claim ALL the funds within the channel.
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justiceTx, err := b.createJusticeTx(breachInfo)
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finalTx, err := b.cfg.Store.GetFinalizedTxn(&breachInfo.chanPoint)
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if err != nil {
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brarLog.Errorf("unable to create justice tx: %v", err)
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brarLog.Errorf("unable to get finalized txn for"+
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"chanid=%v: %v", &breachInfo.chanPoint, err)
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return
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}
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// If this retribution has not been finalized before, we will first
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// construct a sweep transaction and write it to disk. This will allow
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// the breach arbiter to re-register for notifications for the justice
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// txid.
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if finalTx == nil {
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// With the breach transaction confirmed, we now create the
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// justice tx which will claim ALL the funds within the channel.
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finalTx, err = b.createJusticeTx(breachInfo)
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if err != nil {
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brarLog.Errorf("unable to create justice tx: %v", err)
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return
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}
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// Persist our finalized justice transaction before making an
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// attempt to broadcast.
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err := b.cfg.Store.Finalize(&breachInfo.chanPoint, finalTx)
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if err != nil {
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brarLog.Errorf("unable to finalize justice tx for "+
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"chanid=%v: %v", &breachInfo.chanPoint, err)
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return
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}
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}
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brarLog.Debugf("Broadcasting justice tx: %v",
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newLogClosure(func() string {
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return spew.Sdump(justiceTx)
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return spew.Sdump(finalTx)
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}))
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_, currentHeight, err := b.cfg.ChainIO.GetBestBlock()
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if err != nil {
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brarLog.Errorf("unable to get current height: %v", err)
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return
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}
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// Finally, broadcast the transaction, finalizing the channels'
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// retribution against the cheating counterparty.
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if err := b.cfg.PublishTransaction(justiceTx); err != nil {
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if err := b.cfg.PublishTransaction(finalTx); err != nil {
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brarLog.Errorf("unable to broadcast "+
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"justice tx: %v", err)
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return
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}
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|
||||
// As a conclusionary step, we register for a notification to be
|
||||
// dispatched once the justice tx is confirmed. After confirmation we
|
||||
// notify the caller that initiated the retribution workflow that the
|
||||
// deed has been done.
|
||||
justiceTXID := justiceTx.TxHash()
|
||||
justiceTXID := finalTx.TxHash()
|
||||
confChan, err = b.cfg.Notifier.RegisterConfirmationsNtfn(
|
||||
&justiceTXID, 1, uint32(currentHeight))
|
||||
&justiceTXID, 1, breachConfHeight)
|
||||
if err != nil {
|
||||
brarLog.Errorf("unable to register for conf for txid: %v",
|
||||
justiceTXID)
|
||||
|
|
@ -607,6 +599,7 @@ func (b *breachArbiter) exactRetribution(
|
|||
err := b.cfg.DB.MarkChanFullyClosed(&breachInfo.chanPoint)
|
||||
if err != nil {
|
||||
brarLog.Errorf("unable to mark chan as closed: %v", err)
|
||||
return
|
||||
}
|
||||
|
||||
// Justice has been carried out; we can safely delete the
|
||||
|
|
@ -640,7 +633,7 @@ func (b *breachArbiter) breachObserver(contract *lnwallet.LightningChannel,
|
|||
|
||||
defer b.wg.Done()
|
||||
|
||||
chanPoint := contract.ChannelPoint()
|
||||
chanPoint := contract.ChanPoint
|
||||
|
||||
brarLog.Debugf("Breach observer for ChannelPoint(%v) started ",
|
||||
chanPoint)
|
||||
|
|
@ -746,57 +739,39 @@ func (b *breachArbiter) breachObserver(contract *lnwallet.LightningChannel,
|
|||
// mid-local initiated state-transition, possible
|
||||
// false-positive?
|
||||
|
||||
// Obtain a snapshot of the final channel state, which can be
|
||||
// used to reclose a breached channel in the event of a failure.
|
||||
chanInfo := contract.StateSnapshot()
|
||||
|
||||
// Using the breach information provided by the wallet and the
|
||||
// channel snapshot, construct the retribution information that
|
||||
// will be persisted to disk.
|
||||
retInfo := newRetributionInfo(chanPoint, breachInfo, chanInfo)
|
||||
retInfo := newRetributionInfo(chanPoint, breachInfo)
|
||||
|
||||
// Persist the pending retribution state to disk.
|
||||
if err := b.cfg.Store.Add(retInfo); err != nil {
|
||||
brarLog.Errorf("unable to persist retribution info "+
|
||||
"to db: %v", err)
|
||||
err := b.cfg.Store.Add(retInfo)
|
||||
if err != nil {
|
||||
brarLog.Errorf("unable to persist retribution "+
|
||||
"info to db: %v", err)
|
||||
}
|
||||
|
||||
// TODO(conner): move responsibility of channel closure into
|
||||
// lnwallet. Have breach arbiter ACK after writing to disk, then
|
||||
// have wallet mark channel as closed. This allows the wallet to
|
||||
// attempt to retransmit the breach info if the either arbiter
|
||||
// or the wallet goes down before completing the hand off.
|
||||
// Now that the breach has been persisted, try to send an
|
||||
// acknowledgment back to the close observer with the error. If
|
||||
// the ack is successful, the close observer will mark the
|
||||
// channel as pending-closed in the channeldb.
|
||||
select {
|
||||
case breachInfo.Err <- err:
|
||||
// Bail if we failed to persist retribution info.
|
||||
if err != nil {
|
||||
return
|
||||
}
|
||||
|
||||
// Now that the breach arbiter has persisted the information,
|
||||
// we can go ahead and mark the channel as closed in the
|
||||
// channeldb. This step is done after persisting the
|
||||
// retribution information so that a failure between these steps
|
||||
// will cause an attempt to monitor the still-open channel.
|
||||
// However, since the retribution information was persisted
|
||||
// before, the arbiter will recognize that the channel should be
|
||||
// closed, and proceed to mark it as such after a restart, and
|
||||
// forgo monitoring it for breaches.
|
||||
case <-contract.ObserverQuit():
|
||||
// If the close observer has already exited, it will
|
||||
// never read the acknowledgment, so we exit.
|
||||
return
|
||||
|
||||
// Construct the breached channel's close summary marking the
|
||||
// channel using the snapshot from before, and marking this as a
|
||||
// BreachClose.
|
||||
closeInfo := &channeldb.ChannelCloseSummary{
|
||||
ChanPoint: *chanPoint,
|
||||
ChainHash: breachInfo.ChainHash,
|
||||
ClosingTXID: breachInfo.BreachTransaction.TxHash(),
|
||||
RemotePub: &chanInfo.RemoteIdentity,
|
||||
Capacity: chanInfo.Capacity,
|
||||
SettledBalance: chanInfo.LocalBalance.ToSatoshis(),
|
||||
CloseType: channeldb.BreachClose,
|
||||
IsPending: true,
|
||||
}
|
||||
|
||||
// Next, persist the channel close to disk. Upon restart, the
|
||||
// arbiter will recognize that this channel has been breached
|
||||
// and marked close, and fast track its path to justice.
|
||||
if err := contract.DeleteState(closeInfo); err != nil {
|
||||
brarLog.Errorf("unable to delete channel state: %v",
|
||||
err)
|
||||
case <-b.quit:
|
||||
// Cancel the close observer if the breach arbiter is
|
||||
// shutting down, dropping the acknowledgment.
|
||||
contract.CancelObserver()
|
||||
return
|
||||
}
|
||||
|
||||
// Finally, we send the retribution information into the
|
||||
|
|
@ -807,6 +782,8 @@ func (b *breachArbiter) breachObserver(contract *lnwallet.LightningChannel,
|
|||
}
|
||||
|
||||
case <-b.quit:
|
||||
contract.Stop()
|
||||
contract.CancelObserver()
|
||||
return
|
||||
}
|
||||
}
|
||||
|
|
@ -922,20 +899,10 @@ var _ SpendableOutput = (*breachedOutput)(nil)
|
|||
// spends all outputs of the commitment transaction into an output controlled
|
||||
// by the wallet.
|
||||
type retributionInfo struct {
|
||||
commitHash chainhash.Hash
|
||||
chanPoint wire.OutPoint
|
||||
chainHash chainhash.Hash
|
||||
|
||||
// TODO(conner): remove the following group of fields after decoupling
|
||||
// the breach arbiter from the wallet.
|
||||
|
||||
// Fields copied from channel snapshot when a breach is detected. This
|
||||
// is necessary for deterministically constructing the channel close
|
||||
// summary in the event that the breach arbiter crashes before closing
|
||||
// the channel.
|
||||
remoteIdentity *btcec.PublicKey
|
||||
capacity btcutil.Amount
|
||||
settledBalance btcutil.Amount
|
||||
commitHash chainhash.Hash
|
||||
chanPoint wire.OutPoint
|
||||
chainHash chainhash.Hash
|
||||
breachHeight uint32
|
||||
|
||||
breachedOutputs []breachedOutput
|
||||
}
|
||||
|
|
@ -945,8 +912,7 @@ type retributionInfo struct {
|
|||
// channels. The information is primarily populated using the BreachRetribution
|
||||
// delivered by the wallet when it detects a channel breach.
|
||||
func newRetributionInfo(chanPoint *wire.OutPoint,
|
||||
breachInfo *lnwallet.BreachRetribution,
|
||||
chanInfo *channeldb.ChannelSnapshot) *retributionInfo {
|
||||
breachInfo *lnwallet.BreachRetribution) *retributionInfo {
|
||||
|
||||
// Determine the number of second layer HTLCs we will attempt to sweep.
|
||||
nHtlcs := len(breachInfo.HtlcRetributions)
|
||||
|
|
@ -1009,16 +975,10 @@ func newRetributionInfo(chanPoint *wire.OutPoint,
|
|||
breachedOutputs = append(breachedOutputs, htlcOutput)
|
||||
}
|
||||
|
||||
// TODO(conner): remove dependency on channel snapshot after decoupling
|
||||
// channel closure from the breach arbiter.
|
||||
|
||||
return &retributionInfo{
|
||||
commitHash: breachInfo.BreachTransaction.TxHash(),
|
||||
chainHash: chanInfo.ChainHash,
|
||||
chainHash: breachInfo.ChainHash,
|
||||
chanPoint: *chanPoint,
|
||||
remoteIdentity: &chanInfo.RemoteIdentity,
|
||||
capacity: chanInfo.Capacity,
|
||||
settledBalance: chanInfo.LocalBalance.ToSatoshis(),
|
||||
breachedOutputs: breachedOutputs,
|
||||
}
|
||||
}
|
||||
|
|
@ -1226,6 +1186,19 @@ type RetributionStore interface {
|
|||
// the addition fails.
|
||||
Add(retInfo *retributionInfo) error
|
||||
|
||||
// IsBreached queries the retribution store to see if the breach arbiter
|
||||
// is aware of any breaches for the provided channel point.
|
||||
IsBreached(chanPoint *wire.OutPoint) (bool, error)
|
||||
|
||||
// Finalize persists the finalized justice transaction for a particular
|
||||
// channel.
|
||||
Finalize(chanPoint *wire.OutPoint, finalTx *wire.MsgTx) error
|
||||
|
||||
// GetFinalizedTxn loads the finalized justice transaction, if any, from
|
||||
// the retribution store. The finalized transaction will be nil if
|
||||
// Finalize has not yet been called for this channel point.
|
||||
GetFinalizedTxn(chanPoint *wire.OutPoint) (*wire.MsgTx, error)
|
||||
|
||||
// Remove deletes the retributionInfo from disk, if any exists, under
|
||||
// the given key. An error should be re raised if the removal fails.
|
||||
Remove(key *wire.OutPoint) error
|
||||
|
|
@ -1276,8 +1249,97 @@ func (rs *retributionStore) Add(ret *retributionInfo) error {
|
|||
})
|
||||
}
|
||||
|
||||
// Remove removes a retribution state from the retributionStore database.
|
||||
func (rs *retributionStore) Remove(key *wire.OutPoint) error {
|
||||
// Finalize writes a signed justice transaction to the retribution store. This
|
||||
// is done before publishing the transaction, so that we can recover the txid on
|
||||
// startup and re-register for confirmation notifications.
|
||||
func (rs *retributionStore) Finalize(chanPoint *wire.OutPoint,
|
||||
finalTx *wire.MsgTx) error {
|
||||
return rs.db.Update(func(tx *bolt.Tx) error {
|
||||
justiceBkt, err := tx.CreateBucketIfNotExists(justiceTxnBucket)
|
||||
if err != nil {
|
||||
return err
|
||||
}
|
||||
|
||||
var chanBuf bytes.Buffer
|
||||
if err := writeOutpoint(&chanBuf, chanPoint); err != nil {
|
||||
return err
|
||||
}
|
||||
|
||||
var txBuf bytes.Buffer
|
||||
if err := finalTx.Serialize(&txBuf); err != nil {
|
||||
return err
|
||||
}
|
||||
|
||||
return justiceBkt.Put(chanBuf.Bytes(), txBuf.Bytes())
|
||||
})
|
||||
}
|
||||
|
||||
// GetFinalizedTxn loads the finalized justice transaction for the provided
|
||||
// channel point. The finalized transaction will be nil if Finalize has yet to
|
||||
// be called for this channel point.
|
||||
func (rs *retributionStore) GetFinalizedTxn(
|
||||
chanPoint *wire.OutPoint) (*wire.MsgTx, error) {
|
||||
|
||||
var finalTxBytes []byte
|
||||
if err := rs.db.View(func(tx *bolt.Tx) error {
|
||||
justiceBkt := tx.Bucket(justiceTxnBucket)
|
||||
if justiceBkt == nil {
|
||||
return nil
|
||||
}
|
||||
|
||||
var chanBuf bytes.Buffer
|
||||
if err := writeOutpoint(&chanBuf, chanPoint); err != nil {
|
||||
return err
|
||||
}
|
||||
|
||||
finalTxBytes = justiceBkt.Get(chanBuf.Bytes())
|
||||
|
||||
return nil
|
||||
}); err != nil {
|
||||
return nil, err
|
||||
}
|
||||
|
||||
if finalTxBytes == nil {
|
||||
return nil, nil
|
||||
}
|
||||
|
||||
finalTx := &wire.MsgTx{}
|
||||
err := finalTx.Deserialize(bytes.NewReader(finalTxBytes))
|
||||
|
||||
return finalTx, err
|
||||
}
|
||||
|
||||
// IsBreached queries the retribution store to discern if this channel was
|
||||
// previously breached. This is used when connecting to a peer to determine if
|
||||
// it is safe to add a link to the htlcswitch, as we should never add a channel
|
||||
// that has already been breached.
|
||||
func (rs *retributionStore) IsBreached(chanPoint *wire.OutPoint) (bool, error) {
|
||||
var found bool
|
||||
err := rs.db.View(func(tx *bolt.Tx) error {
|
||||
retBucket := tx.Bucket(retributionBucket)
|
||||
if retBucket == nil {
|
||||
return nil
|
||||
}
|
||||
|
||||
var chanBuf bytes.Buffer
|
||||
if err := writeOutpoint(&chanBuf, chanPoint); err != nil {
|
||||
return err
|
||||
}
|
||||
|
||||
retInfo := retBucket.Get(chanBuf.Bytes())
|
||||
if retInfo != nil {
|
||||
found = true
|
||||
}
|
||||
|
||||
return nil
|
||||
})
|
||||
|
||||
return found, err
|
||||
}
|
||||
|
||||
// Remove removes a retribution state and finalized justice transaction by
|
||||
// channel point from the retribution store.
|
||||
func (rs *retributionStore) Remove(chanPoint *wire.OutPoint) error {
|
||||
return rs.db.Update(func(tx *bolt.Tx) error {
|
||||
retBucket := tx.Bucket(retributionBucket)
|
||||
|
||||
|
|
@ -1287,15 +1349,30 @@ func (rs *retributionStore) Remove(key *wire.OutPoint) error {
|
|||
// stored in the db.
|
||||
if retBucket == nil {
|
||||
return errors.New("unable to remove retribution " +
|
||||
"because the db bucket doesn't exist.")
|
||||
"because the retribution bucket doesn't exist.")
|
||||
}
|
||||
|
||||
var outBuf bytes.Buffer
|
||||
if err := writeOutpoint(&outBuf, key); err != nil {
|
||||
// Serialize the channel point we are intending to remove.
|
||||
var chanBuf bytes.Buffer
|
||||
if err := writeOutpoint(&chanBuf, chanPoint); err != nil {
|
||||
return err
|
||||
}
|
||||
chanBytes := chanBuf.Bytes()
|
||||
|
||||
// Remove the persisted retribution info and finalized justice
|
||||
// transaction.
|
||||
if err := retBucket.Delete(chanBytes); err != nil {
|
||||
return err
|
||||
}
|
||||
|
||||
return retBucket.Delete(outBuf.Bytes())
|
||||
// If we have not finalized this channel breach, we can exit
|
||||
// early.
|
||||
justiceBkt := tx.Bucket(justiceTxnBucket)
|
||||
if justiceBkt == nil {
|
||||
return nil
|
||||
}
|
||||
|
||||
return justiceBkt.Delete(chanBytes)
|
||||
})
|
||||
}
|
||||
|
||||
|
|
@ -1313,11 +1390,10 @@ func (rs *retributionStore) ForAll(cb func(*retributionInfo) error) error {
|
|||
// Otherwise, we fetch each serialized retribution info,
|
||||
// deserialize it, and execute the passed in callback function
|
||||
// on it.
|
||||
return retBucket.ForEach(func(outBytes, retBytes []byte) error {
|
||||
return retBucket.ForEach(func(_, retBytes []byte) error {
|
||||
ret := &retributionInfo{}
|
||||
if err := ret.Decode(
|
||||
bytes.NewBuffer(retBytes),
|
||||
); err != nil {
|
||||
err := ret.Decode(bytes.NewBuffer(retBytes))
|
||||
if err != nil {
|
||||
return err
|
||||
}
|
||||
|
||||
|
|
@ -1328,7 +1404,7 @@ func (rs *retributionStore) ForAll(cb func(*retributionInfo) error) error {
|
|||
|
||||
// Encode serializes the retribution into the passed byte stream.
|
||||
func (ret *retributionInfo) Encode(w io.Writer) error {
|
||||
var scratch [8]byte
|
||||
var scratch [4]byte
|
||||
|
||||
if _, err := w.Write(ret.commitHash[:]); err != nil {
|
||||
return err
|
||||
|
|
@ -1342,18 +1418,8 @@ func (ret *retributionInfo) Encode(w io.Writer) error {
|
|||
return err
|
||||
}
|
||||
|
||||
if _, err := w.Write(
|
||||
ret.remoteIdentity.SerializeCompressed()); err != nil {
|
||||
return err
|
||||
}
|
||||
|
||||
binary.BigEndian.PutUint64(scratch[:8], uint64(ret.capacity))
|
||||
if _, err := w.Write(scratch[:8]); err != nil {
|
||||
return err
|
||||
}
|
||||
|
||||
binary.BigEndian.PutUint64(scratch[:8], uint64(ret.settledBalance))
|
||||
if _, err := w.Write(scratch[:8]); err != nil {
|
||||
binary.BigEndian.PutUint32(scratch[:], ret.breachHeight)
|
||||
if _, err := w.Write(scratch[:]); err != nil {
|
||||
return err
|
||||
}
|
||||
|
||||
|
|
@ -1373,12 +1439,12 @@ func (ret *retributionInfo) Encode(w io.Writer) error {
|
|||
|
||||
// Dencode deserializes a retribution from the passed byte stream.
|
||||
func (ret *retributionInfo) Decode(r io.Reader) error {
|
||||
var scratch [33]byte
|
||||
var scratch [32]byte
|
||||
|
||||
if _, err := io.ReadFull(r, scratch[:32]); err != nil {
|
||||
if _, err := io.ReadFull(r, scratch[:]); err != nil {
|
||||
return err
|
||||
}
|
||||
hash, err := chainhash.NewHash(scratch[:32])
|
||||
hash, err := chainhash.NewHash(scratch[:])
|
||||
if err != nil {
|
||||
return err
|
||||
}
|
||||
|
|
@ -1388,34 +1454,19 @@ func (ret *retributionInfo) Decode(r io.Reader) error {
|
|||
return err
|
||||
}
|
||||
|
||||
if _, err := io.ReadFull(r, scratch[:32]); err != nil {
|
||||
if _, err := io.ReadFull(r, scratch[:]); err != nil {
|
||||
return err
|
||||
}
|
||||
chainHash, err := chainhash.NewHash(scratch[:32])
|
||||
chainHash, err := chainhash.NewHash(scratch[:])
|
||||
if err != nil {
|
||||
return err
|
||||
}
|
||||
ret.chainHash = *chainHash
|
||||
|
||||
if _, err = io.ReadFull(r, scratch[:33]); err != nil {
|
||||
if _, err := io.ReadFull(r, scratch[:4]); err != nil {
|
||||
return err
|
||||
}
|
||||
remoteIdentity, err := btcec.ParsePubKey(scratch[:33], btcec.S256())
|
||||
if err != nil {
|
||||
return err
|
||||
}
|
||||
ret.remoteIdentity = remoteIdentity
|
||||
|
||||
if _, err := io.ReadFull(r, scratch[:8]); err != nil {
|
||||
return err
|
||||
}
|
||||
ret.capacity = btcutil.Amount(binary.BigEndian.Uint64(scratch[:8]))
|
||||
|
||||
if _, err := io.ReadFull(r, scratch[:8]); err != nil {
|
||||
return err
|
||||
}
|
||||
ret.settledBalance = btcutil.Amount(
|
||||
binary.BigEndian.Uint64(scratch[:8]))
|
||||
ret.breachHeight = binary.BigEndian.Uint32(scratch[:4])
|
||||
|
||||
nOutputsU64, err := wire.ReadVarInt(r, 0)
|
||||
if err != nil {
|
||||
|
|
|
|||
Loading…
Reference in New Issue
Block a user