Merge pull request #2075 from wpaulino/settle-invoice-on-chain-sweep

contractcourt: settle invoice when claiming HTLC on-chain
This commit is contained in:
Olaoluwa Osuntokun 2019-01-23 16:50:54 -08:00 committed by GitHub
commit 6c610d977f
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GPG Key ID: 4AEE18F83AFDEB23
8 changed files with 245 additions and 59 deletions

@ -6,8 +6,6 @@ import (
"sync"
"sync/atomic"
"github.com/lightningnetwork/lnd/sweep"
"github.com/btcsuite/btcd/chaincfg/chainhash"
"github.com/btcsuite/btcd/wire"
"github.com/btcsuite/btcutil"
@ -15,6 +13,7 @@ import (
"github.com/lightningnetwork/lnd/channeldb"
"github.com/lightningnetwork/lnd/lnwallet"
"github.com/lightningnetwork/lnd/lnwire"
"github.com/lightningnetwork/lnd/sweep"
)
// ErrChainArbExiting signals that the chain arbitrator is shutting down.
@ -135,6 +134,11 @@ type ChainArbitratorConfig struct {
// Sweeper allows resolvers to sweep their final outputs.
Sweeper *sweep.UtxoSweeper
// SettleInvoice attempts to settle an existing invoice on-chain with
// the given payment hash. ErrInvoiceNotFound is returned if an invoice
// is not found.
SettleInvoice func(chainhash.Hash, lnwire.MilliSatoshi) error
}
// ChainArbitrator is a sub-system that oversees the on-chain resolution of all

@ -243,8 +243,7 @@ func (c *ChannelArbitrator) Start() error {
}
var (
err error
unresolvedContracts []ContractResolver
err error
)
log.Debugf("Starting ChannelArbitrator(%v), htlc_set=%v",
@ -332,23 +331,10 @@ func (c *ChannelArbitrator) Start() error {
if startingState == StateWaitingFullResolution &&
nextState == StateWaitingFullResolution {
// We'll now query our log to see if there are any active
// unresolved contracts. If this is the case, then we'll
// relaunch all contract resolvers.
unresolvedContracts, err = c.log.FetchUnresolvedContracts()
if err != nil {
if err := c.relaunchResolvers(); err != nil {
c.cfg.BlockEpochs.Cancel()
return err
}
log.Infof("ChannelArbitrator(%v): relaunching %v contract "+
"resolvers", c.cfg.ChanPoint, len(unresolvedContracts))
c.activeResolvers = unresolvedContracts
for _, contract := range unresolvedContracts {
c.wg.Add(1)
go c.resolveContract(contract)
}
}
// TODO(roasbeef): cancel if breached
@ -358,6 +344,123 @@ func (c *ChannelArbitrator) Start() error {
return nil
}
// relauchResolvers relaunches the set of resolvers for unresolved contracts in
// order to provide them with information that's not immediately available upon
// starting the ChannelArbitrator. This information should ideally be stored in
// the database, so this only serves as a intermediate work-around to prevent a
// migration.
func (c *ChannelArbitrator) relaunchResolvers() error {
// We'll now query our log to see if there are any active
// unresolved contracts. If this is the case, then we'll
// relaunch all contract resolvers.
unresolvedContracts, err := c.log.FetchUnresolvedContracts()
if err != nil {
return err
}
// Retrieve the commitment tx hash from the log.
contractResolutions, err := c.log.FetchContractResolutions()
if err != nil {
log.Errorf("unable to fetch contract resolutions: %v",
err)
return err
}
commitHash := contractResolutions.CommitHash
// Reconstruct the htlc outpoints and data from the chain action log.
// The purpose of the constructed htlc map is to supplement to resolvers
// restored from database with extra data. Ideally this data is stored
// as part of the resolver in the log. This is a workaround to prevent a
// db migration.
htlcMap := make(map[wire.OutPoint]*channeldb.HTLC)
chainActions, err := c.log.FetchChainActions()
if err != nil {
log.Errorf("unable to fetch chain actions: %v", err)
return err
}
for _, htlcs := range chainActions {
for _, htlc := range htlcs {
outpoint := wire.OutPoint{
Hash: commitHash,
Index: uint32(htlc.OutputIndex),
}
htlcMap[outpoint] = &htlc
}
}
log.Infof("ChannelArbitrator(%v): relaunching %v contract "+
"resolvers", c.cfg.ChanPoint, len(unresolvedContracts))
for _, resolver := range unresolvedContracts {
supplementResolver(resolver, htlcMap)
}
c.launchResolvers(unresolvedContracts)
return nil
}
// supplementResolver takes a resolver as it is restored from the log and fills
// in missing data from the htlcMap.
func supplementResolver(resolver ContractResolver,
htlcMap map[wire.OutPoint]*channeldb.HTLC) error {
switch r := resolver.(type) {
case *htlcSuccessResolver:
return supplementSuccessResolver(r, htlcMap)
case *htlcIncomingContestResolver:
return supplementSuccessResolver(
&r.htlcSuccessResolver, htlcMap,
)
case *htlcTimeoutResolver:
return supplementTimeoutResolver(r, htlcMap)
case *htlcOutgoingContestResolver:
return supplementTimeoutResolver(
&r.htlcTimeoutResolver, htlcMap,
)
}
return nil
}
// supplementSuccessResolver takes a htlcSuccessResolver as it is restored from
// the log and fills in missing data from the htlcMap.
func supplementSuccessResolver(r *htlcSuccessResolver,
htlcMap map[wire.OutPoint]*channeldb.HTLC) error {
res := r.htlcResolution
htlcPoint := res.HtlcPoint()
htlc, ok := htlcMap[htlcPoint]
if !ok {
return errors.New(
"htlc for success resolver unavailable",
)
}
r.htlcAmt = htlc.Amt
return nil
}
// supplementTimeoutResolver takes a htlcSuccessResolver as it is restored from
// the log and fills in missing data from the htlcMap.
func supplementTimeoutResolver(r *htlcTimeoutResolver,
htlcMap map[wire.OutPoint]*channeldb.HTLC) error {
res := r.htlcResolution
htlcPoint := res.HtlcPoint()
htlc, ok := htlcMap[htlcPoint]
if !ok {
return errors.New(
"htlc for timeout resolver unavailable",
)
}
r.htlcAmt = htlc.Amt
return nil
}
// Stop signals the ChannelArbitrator for a graceful shutdown.
func (c *ChannelArbitrator) Stop() error {
if !atomic.CompareAndSwapInt32(&c.stopped, 0, 1) {
@ -703,11 +806,7 @@ func (c *ChannelArbitrator) stateStep(triggerHeight uint32,
// Finally, we'll launch all the required contract resolvers.
// Once they're all resolved, we're no longer needed.
c.activeResolvers = htlcResolvers
for _, contract := range htlcResolvers {
c.wg.Add(1)
go c.resolveContract(contract)
}
c.launchResolvers(htlcResolvers)
nextState = StateWaitingFullResolution
@ -741,6 +840,15 @@ func (c *ChannelArbitrator) stateStep(triggerHeight uint32,
return nextState, closeTx, nil
}
// launchResolvers updates the activeResolvers list and starts the resolvers.
func (c *ChannelArbitrator) launchResolvers(resolvers []ContractResolver) {
c.activeResolvers = resolvers
for _, contract := range resolvers {
c.wg.Add(1)
go c.resolveContract(contract)
}
}
// advanceState is the main driver of our state machine. This method is an
// iterative function which repeatedly attempts to advance the internal state
// of the channel arbitrator. The state will be advanced until we reach a
@ -1071,33 +1179,11 @@ func (c *ChannelArbitrator) prepContractResolutions(htlcActions ChainActionMap,
inResolutionMap := make(map[wire.OutPoint]lnwallet.IncomingHtlcResolution)
for i := 0; i < len(incomingResolutions); i++ {
inRes := incomingResolutions[i]
// If we have a success transaction, then the htlc's outpoint
// is the transaction's only input. Otherwise, it's the claim
// point.
var htlcPoint wire.OutPoint
if inRes.SignedSuccessTx != nil {
htlcPoint = inRes.SignedSuccessTx.TxIn[0].PreviousOutPoint
} else {
htlcPoint = inRes.ClaimOutpoint
}
inResolutionMap[htlcPoint] = inRes
inResolutionMap[inRes.HtlcPoint()] = inRes
}
for i := 0; i < len(outgoingResolutions); i++ {
outRes := outgoingResolutions[i]
// If we have a timeout transaction, then the htlc's outpoint
// is the transaction's only input. Otherwise, it's the claim
// point.
var htlcPoint wire.OutPoint
if outRes.SignedTimeoutTx != nil {
htlcPoint = outRes.SignedTimeoutTx.TxIn[0].PreviousOutPoint
} else {
htlcPoint = outRes.ClaimOutpoint
}
outResolutionMap[htlcPoint] = outRes
outResolutionMap[outRes.HtlcPoint()] = outRes
}
// We'll create the resolver kit that we'll be cloning for each
@ -1155,6 +1241,7 @@ func (c *ChannelArbitrator) prepContractResolutions(htlcActions ChainActionMap,
htlcResolution: resolution,
broadcastHeight: height,
payHash: htlc.RHash,
htlcAmt: htlc.Amt,
ResolverKit: resKit,
}
htlcResolvers = append(htlcResolvers, resolver)
@ -1182,6 +1269,7 @@ func (c *ChannelArbitrator) prepContractResolutions(htlcActions ChainActionMap,
htlcResolution: resolution,
broadcastHeight: height,
htlcIndex: htlc.HtlcIndex,
htlcAmt: htlc.Amt,
ResolverKit: resKit,
}
htlcResolvers = append(htlcResolvers, resolver)
@ -1215,6 +1303,7 @@ func (c *ChannelArbitrator) prepContractResolutions(htlcActions ChainActionMap,
htlcResolution: resolution,
broadcastHeight: height,
payHash: htlc.RHash,
htlcAmt: htlc.Amt,
ResolverKit: resKit,
},
}
@ -1241,10 +1330,11 @@ func (c *ChannelArbitrator) prepContractResolutions(htlcActions ChainActionMap,
resKit.Quit = make(chan struct{})
resolver := &htlcOutgoingContestResolver{
htlcTimeoutResolver{
htlcTimeoutResolver: htlcTimeoutResolver{
htlcResolution: resolution,
broadcastHeight: height,
htlcIndex: htlc.HtlcIndex,
htlcAmt: htlc.Amt,
ResolverKit: resKit,
},
}

@ -175,6 +175,9 @@ func createTestChannelArbitrator(log ArbitratorLog) (*ChannelArbitrator,
*lnwallet.IncomingHtlcResolution, uint32) error {
return nil
},
SettleInvoice: func(chainhash.Hash, lnwire.MilliSatoshi) error {
return nil
},
}
// We'll use the resolvedChan to synchronize on call to

@ -5,6 +5,9 @@ import (
"fmt"
"io"
"github.com/lightningnetwork/lnd/channeldb"
"github.com/lightningnetwork/lnd/lnwire"
"github.com/btcsuite/btcd/wire"
"github.com/davecgh/go-spew/spew"
"github.com/lightningnetwork/lnd/lnwallet"
@ -46,6 +49,10 @@ type htlcSuccessResolver struct {
// TODO(roasbeef): send off to utxobundler
sweepTx *wire.MsgTx
// htlcAmt is the original amount of the htlc, not taking into
// account any fees that may have to be paid if it goes on chain.
htlcAmt lnwire.MilliSatoshi
ResolverKit
}
@ -169,6 +176,14 @@ func (h *htlcSuccessResolver) Resolve() (ContractResolver, error) {
return nil, fmt.Errorf("quitting")
}
// With the HTLC claimed, we can attempt to settle its
// corresponding invoice if we were the original destination.
err = h.SettleInvoice(h.payHash, h.htlcAmt)
if err != nil && err != channeldb.ErrInvoiceNotFound {
log.Errorf("Unable to settle invoice with payment "+
"hash %x: %v", h.payHash, err)
}
// Once the transaction has received a sufficient number of
// confirmations, we'll mark ourselves as fully resolved and exit.
h.resolved = true
@ -234,6 +249,14 @@ func (h *htlcSuccessResolver) Resolve() (ContractResolver, error) {
return nil, fmt.Errorf("quitting")
}
// With the HTLC claimed, we can attempt to settle its corresponding
// invoice if we were the original destination.
err = h.SettleInvoice(h.payHash, h.htlcAmt)
if err != nil && err != channeldb.ErrInvoiceNotFound {
log.Errorf("Unable to settle invoice with payment "+
"hash %x: %v", h.payHash, err)
}
h.resolved = true
return nil, h.Checkpoint(h)
}

@ -40,6 +40,10 @@ type htlcTimeoutResolver struct {
// additional commitment state machine.
htlcIndex uint64
// htlcAmt is the original amount of the htlc, not taking into
// account any fees that may have to be paid if it goes on chain.
htlcAmt lnwire.MilliSatoshi
ResolverKit
}

@ -4,23 +4,20 @@ package main
import (
"bytes"
"crypto/rand"
"crypto/sha256"
"encoding/hex"
"fmt"
"io"
"io/ioutil"
"os"
"path/filepath"
"reflect"
"strings"
"sync/atomic"
"testing"
"time"
"sync/atomic"
"encoding/hex"
"reflect"
"crypto/rand"
"crypto/sha256"
"github.com/btcsuite/btcd/btcjson"
"github.com/btcsuite/btcd/chaincfg"
"github.com/btcsuite/btcd/chaincfg/chainhash"
@ -9320,8 +9317,9 @@ func testMultiHopReceiverChainClaim(net *lntest.NetworkHarness, t *harnessTest)
defer shutdownAndAssert(net, t, carol)
// With the network active, we'll now add a new invoice at Carol's end.
const invoiceAmt = 100000
invoiceReq := &lnrpc.Invoice{
Value: 100000,
Value: invoiceAmt,
}
ctxt, _ := context.WithTimeout(ctxb, defaultTimeout)
carolInvoice, err := carol.AddInvoice(ctxt, invoiceReq)
@ -9527,6 +9525,25 @@ func testMultiHopReceiverChainClaim(net *lntest.NetworkHarness, t *harnessTest)
t.Fatalf(predErr.Error())
}
// The invoice should show as settled for Carol, indicating that it was
// swept on-chain.
invoicesReq := &lnrpc.ListInvoiceRequest{}
invoicesResp, err := carol.ListInvoices(ctxb, invoicesReq)
if err != nil {
t.Fatalf("unable to retrieve invoices: %v", err)
}
if len(invoicesResp.Invoices) != 1 {
t.Fatalf("expected 1 invoice, got %d", len(invoicesResp.Invoices))
}
invoice := invoicesResp.Invoices[0]
if invoice.State != lnrpc.Invoice_SETTLED {
t.Fatalf("expected invoice to be settled on chain")
}
if invoice.AmtPaidSat != invoiceAmt {
t.Fatalf("expected invoice to be settled with %d sat, got "+
"%d sat", invoiceAmt, invoice.AmtPaidSat)
}
// We'll close out the channel between Alice and Bob, then shutdown
// carol to conclude the test.
ctxt, _ = context.WithTimeout(ctxb, channelCloseTimeout)
@ -10368,8 +10385,9 @@ func testMultiHopHtlcRemoteChainClaim(net *lntest.NetworkHarness, t *harnessTest
defer shutdownAndAssert(net, t, carol)
// With the network active, we'll now add a new invoice at Carol's end.
const invoiceAmt = 100000
invoiceReq := &lnrpc.Invoice{
Value: 100000,
Value: invoiceAmt,
}
ctxt, _ := context.WithTimeout(ctxb, defaultTimeout)
carolInvoice, err := carol.AddInvoice(ctxt, invoiceReq)
@ -10611,6 +10629,25 @@ func testMultiHopHtlcRemoteChainClaim(net *lntest.NetworkHarness, t *harnessTest
if err != nil {
t.Fatalf(predErr.Error())
}
// The invoice should show as settled for Carol, indicating that it was
// swept on-chain.
invoicesReq := &lnrpc.ListInvoiceRequest{}
invoicesResp, err := carol.ListInvoices(ctxb, invoicesReq)
if err != nil {
t.Fatalf("unable to retrieve invoices: %v", err)
}
if len(invoicesResp.Invoices) != 1 {
t.Fatalf("expected 1 invoice, got %d", len(invoicesResp.Invoices))
}
invoice := invoicesResp.Invoices[0]
if invoice.State != lnrpc.Invoice_SETTLED {
t.Fatalf("expected invoice to be settled on chain")
}
if invoice.AmtPaidSat != invoiceAmt {
t.Fatalf("expected invoice to be settled with %d sat, got "+
"%d sat", invoiceAmt, invoice.AmtPaidSat)
}
}
// testSwitchCircuitPersistence creates a multihop network to ensure the sender

@ -5499,6 +5499,30 @@ func newIncomingHtlcResolution(signer Signer, localChanCfg *channeldb.ChannelCon
}, nil
}
// HtlcPoint returns the htlc's outpoint on the commitment tx.
func (r *IncomingHtlcResolution) HtlcPoint() wire.OutPoint {
// If we have a success transaction, then the htlc's outpoint
// is the transaction's only input. Otherwise, it's the claim
// point.
if r.SignedSuccessTx != nil {
return r.SignedSuccessTx.TxIn[0].PreviousOutPoint
}
return r.ClaimOutpoint
}
// HtlcPoint returns the htlc's outpoint on the commitment tx.
func (r *OutgoingHtlcResolution) HtlcPoint() wire.OutPoint {
// If we have a timeout transaction, then the htlc's outpoint
// is the transaction's only input. Otherwise, it's the claim
// point.
if r.SignedTimeoutTx != nil {
return r.SignedTimeoutTx.TxIn[0].PreviousOutPoint
}
return r.ClaimOutpoint
}
// extractHtlcResolutions creates a series of outgoing HTLC resolutions, and
// the local key used when generating the HTLC scrips. This function is to be
// used in two cases: force close, or a unilateral close.

@ -728,7 +728,8 @@ func newServer(listenAddrs []net.Addr, chanDB *channeldb.DB, cc *chainControl,
DisableChannel: func(op wire.OutPoint) error {
return s.announceChanStatus(op, true)
},
Sweeper: s.sweeper,
Sweeper: s.sweeper,
SettleInvoice: s.invoices.SettleInvoice,
}, chanDB)
s.breachArbiter = newBreachArbiter(&BreachConfig{