lnd.xprv/lntest/itest/lnd_multi-hop_htlc_local_chain_claim_test.go
Johan T. Halseth 4b9fbe2146
itest/local_chain_claim test: mine one less blocks for anchor sweeps
In case of anchor channel types, we mine one less block before we expect
the second level sweep to appear in the mempool, since the sweeper
sweeps one block earlier than the nursery.
2020-12-10 14:24:21 +01:00

311 lines
10 KiB
Go

package itest
import (
"context"
"fmt"
"github.com/btcsuite/btcd/wire"
"github.com/lightningnetwork/lnd"
"github.com/lightningnetwork/lnd/lncfg"
"github.com/lightningnetwork/lnd/lnrpc"
"github.com/lightningnetwork/lnd/lnrpc/invoicesrpc"
"github.com/lightningnetwork/lnd/lnrpc/routerrpc"
"github.com/lightningnetwork/lnd/lntest"
"github.com/lightningnetwork/lnd/lntest/wait"
"github.com/lightningnetwork/lnd/lntypes"
"github.com/stretchr/testify/require"
)
// testMultiHopHtlcLocalChainClaim tests that in a multi-hop HTLC scenario, if
// we force close a channel with an incoming HTLC, and later find out the
// preimage via the witness beacon, we properly settle the HTLC on-chain using
// the HTLC success transaction in order to ensure we don't lose any funds.
func testMultiHopHtlcLocalChainClaim(net *lntest.NetworkHarness, t *harnessTest,
alice, bob *lntest.HarnessNode, c commitType) {
ctxb := context.Background()
// First, we'll create a three hop network: Alice -> Bob -> Carol, with
// Carol refusing to actually settle or directly cancel any HTLC's
// self.
aliceChanPoint, bobChanPoint, carol := createThreeHopNetwork(
t, net, alice, bob, false, c,
)
// Clean up carol's node when the test finishes.
defer shutdownAndAssert(net, t, carol)
// With the network active, we'll now add a new hodl invoice at Carol's
// end. Make sure the cltv expiry delta is large enough, otherwise Bob
// won't send out the outgoing htlc.
const invoiceAmt = 100000
preimage := lntypes.Preimage{1, 2, 3}
payHash := preimage.Hash()
invoiceReq := &invoicesrpc.AddHoldInvoiceRequest{
Value: invoiceAmt,
CltvExpiry: 40,
Hash: payHash[:],
}
ctxt, cancel := context.WithTimeout(ctxb, defaultTimeout)
defer cancel()
carolInvoice, err := carol.AddHoldInvoice(ctxt, invoiceReq)
require.NoError(t.t, err)
// Now that we've created the invoice, we'll send a single payment from
// Alice to Carol. We won't wait for the response however, as Carol
// will not immediately settle the payment.
ctx, cancel := context.WithCancel(ctxb)
defer cancel()
_, err = alice.RouterClient.SendPaymentV2(
ctx, &routerrpc.SendPaymentRequest{
PaymentRequest: carolInvoice.PaymentRequest,
TimeoutSeconds: 60,
FeeLimitMsat: noFeeLimitMsat,
},
)
require.NoError(t.t, err)
// At this point, all 3 nodes should now have an active channel with
// the created HTLC pending on all of them.
nodes := []*lntest.HarnessNode{alice, bob, carol}
err = wait.NoError(func() error {
return assertActiveHtlcs(nodes, payHash[:])
}, defaultTimeout)
require.NoError(t.t, err)
// Wait for carol to mark invoice as accepted. There is a small gap to
// bridge between adding the htlc to the channel and executing the exit
// hop logic.
waitForInvoiceAccepted(t, carol, payHash)
// Increase the fee estimate so that the following force close tx will
// be cpfp'ed.
net.SetFeeEstimate(30000)
// At this point, Bob decides that he wants to exit the channel
// immediately, so he force closes his commitment transaction.
ctxt, _ = context.WithTimeout(ctxb, channelCloseTimeout)
bobForceClose := closeChannelAndAssertType(
ctxt, t, net, bob, aliceChanPoint, c == commitTypeAnchors, true,
)
// Alice will sweep her commitment output immediately. If there are
// anchors, Alice will also sweep hers.
expectedTxes := 1
if c == commitTypeAnchors {
expectedTxes = 2
}
_, err = waitForNTxsInMempool(
net.Miner.Node, expectedTxes, minerMempoolTimeout,
)
require.NoError(t.t, err)
// Suspend Bob to force Carol to go to chain.
restartBob, err := net.SuspendNode(bob)
require.NoError(t.t, err)
// Settle invoice. This will just mark the invoice as settled, as there
// is no link anymore to remove the htlc from the commitment tx. For
// this test, it is important to actually settle and not leave the
// invoice in the accepted state, because without a known preimage, the
// channel arbitrator won't go to chain.
ctx, cancel = context.WithTimeout(ctxb, defaultTimeout)
defer cancel()
_, err = carol.SettleInvoice(ctx, &invoicesrpc.SettleInvoiceMsg{
Preimage: preimage[:],
})
require.NoError(t.t, err)
// We'll now mine enough blocks so Carol decides that she needs to go
// on-chain to claim the HTLC as Bob has been inactive.
numBlocks := padCLTV(uint32(invoiceReq.CltvExpiry -
lncfg.DefaultIncomingBroadcastDelta))
_, err = net.Miner.Node.Generate(numBlocks)
require.NoError(t.t, err)
// Carol's commitment transaction should now be in the mempool. If there
// is an anchor, Carol will sweep that too.
_, err = waitForNTxsInMempool(
net.Miner.Node, expectedTxes, minerMempoolTimeout,
)
require.NoError(t.t, err)
bobFundingTxid, err := lnd.GetChanPointFundingTxid(bobChanPoint)
require.NoError(t.t, err)
carolFundingPoint := wire.OutPoint{
Hash: *bobFundingTxid,
Index: bobChanPoint.OutputIndex,
}
// Look up the closing transaction. It should be spending from the
// funding transaction,
closingTx := getSpendingTxInMempool(
t, net.Miner.Node, minerMempoolTimeout, carolFundingPoint,
)
closingTxid := closingTx.TxHash()
// Mine a block that should confirm the commit tx, the anchor if present
// and the coinbase.
block := mineBlocks(t, net, 1, expectedTxes)[0]
require.Len(t.t, block.Transactions, expectedTxes+1)
assertTxInBlock(t, block, &closingTxid)
// Restart bob again.
err = restartBob()
require.NoError(t.t, err)
// After the force close transacion is mined, Carol should broadcast her
// second level HTLC transacion. Bob will broadcast a sweep tx to sweep
// his output in the channel with Carol. He can do this immediately, as
// the output is not timelocked since Carol was the one force closing.
// If there are anchors on the commitment, Bob will also sweep his
// anchor.
expectedTxes = 2
if c == commitTypeAnchors {
expectedTxes = 3
}
txes, err := getNTxsFromMempool(
net.Miner.Node, expectedTxes, minerMempoolTimeout,
)
require.NoError(t.t, err)
// Both Carol's second level transaction and Bob's sweep should be
// spending from the commitment transaction.
assertAllTxesSpendFrom(t, txes, closingTxid)
// At this point we suspend Alice to make sure she'll handle the
// on-chain settle after a restart.
restartAlice, err := net.SuspendNode(alice)
require.NoError(t.t, err)
// Mine a block to confirm the two transactions (+ the coinbase).
block = mineBlocks(t, net, 1, expectedTxes)[0]
require.Len(t.t, block.Transactions, expectedTxes+1)
var secondLevelMaturity uint32
switch c {
// If this is a channel of the anchor type, we will subtract one block
// from the default CSV, as the Sweeper will handle the input, and the Sweeper
// sweeps the input as soon as the lock expires.
case commitTypeAnchors:
secondLevelMaturity = defaultCSV - 1
// For non-anchor channel types, the nursery will handle sweeping the
// second level output, and it will wait one extra block before
// sweeping it.
default:
secondLevelMaturity = defaultCSV
}
// Keep track of the second level tx maturity.
carolSecondLevelCSV := secondLevelMaturity
// When Bob notices Carol's second level transaction in the block, he
// will extract the preimage and broadcast a second level tx to claim
// the HTLC in his (already closed) channel with Alice.
bobSecondLvlTx, err := waitForTxInMempool(
net.Miner.Node, minerMempoolTimeout,
)
require.NoError(t.t, err)
// It should spend from the commitment in the channel with Alice.
tx, err := net.Miner.Node.GetRawTransaction(bobSecondLvlTx)
require.NoError(t.t, err)
require.Equal(
t.t, *bobForceClose, tx.MsgTx().TxIn[0].PreviousOutPoint.Hash,
)
// At this point, Bob should have broadcast his second layer success
// transaction, and should have sent it to the nursery for incubation.
ctxt, _ = context.WithTimeout(ctxb, defaultTimeout)
err = waitForNumChannelPendingForceClose(
ctxt, bob, 1, func(c *lnrpcForceCloseChannel) error {
if c.Channel.LocalBalance != 0 {
return nil
}
if len(c.PendingHtlcs) != 1 {
return fmt.Errorf("bob should have pending " +
"htlc but doesn't")
}
if c.PendingHtlcs[0].Stage != 1 {
return fmt.Errorf("bob's htlc should have "+
"advanced to the first stage but was "+
"stage: %v", c.PendingHtlcs[0].Stage)
}
return nil
},
)
require.NoError(t.t, err)
// We'll now mine a block which should confirm Bob's second layer
// transaction.
block = mineBlocks(t, net, 1, 1)[0]
require.Len(t.t, block.Transactions, 2)
assertTxInBlock(t, block, bobSecondLvlTx)
// Keep track of Bob's second level maturity, and decrement our track
// of Carol's.
bobSecondLevelCSV := secondLevelMaturity
carolSecondLevelCSV--
// Now that the preimage from Bob has hit the chain, restart Alice to
// ensure she'll pick it up.
err = restartAlice()
require.NoError(t.t, err)
// If we then mine 3 additional blocks, Carol's second level tx should
// mature, and she can pull the funds from it with a sweep tx.
_, err = net.Miner.Node.Generate(carolSecondLevelCSV)
require.NoError(t.t, err)
bobSecondLevelCSV -= carolSecondLevelCSV
carolSweep, err := waitForTxInMempool(net.Miner.Node, minerMempoolTimeout)
require.NoError(t.t, err)
// Mining one additional block, Bob's second level tx is mature, and he
// can sweep the output.
block = mineBlocks(t, net, bobSecondLevelCSV, 1)[0]
assertTxInBlock(t, block, carolSweep)
bobSweep, err := waitForTxInMempool(net.Miner.Node, minerMempoolTimeout)
require.NoError(t.t, err)
// Make sure it spends from the second level tx.
tx, err = net.Miner.Node.GetRawTransaction(bobSweep)
require.NoError(t.t, err)
require.Equal(
t.t, *bobSecondLvlTx, tx.MsgTx().TxIn[0].PreviousOutPoint.Hash,
)
// When we mine one additional block, that will confirm Bob's sweep.
// Now Bob should have no pending channels anymore, as this just
// resolved it by the confirmation of the sweep transaction.
block = mineBlocks(t, net, 1, 1)[0]
assertTxInBlock(t, block, bobSweep)
ctxt, _ = context.WithTimeout(ctxb, defaultTimeout)
err = waitForNumChannelPendingForceClose(ctxt, bob, 0, nil)
require.NoError(t.t, err)
assertNodeNumChannels(t, bob, 0)
// Also Carol should have no channels left (open nor pending).
err = waitForNumChannelPendingForceClose(ctxt, carol, 0, nil)
require.NoError(t.t, err)
assertNodeNumChannels(t, carol, 0)
// Finally, check that the Alice's payment is correctly marked
// succeeded.
ctxt, _ = context.WithTimeout(ctxt, defaultTimeout)
err = checkPaymentStatus(
ctxt, alice, preimage, lnrpc.Payment_SUCCEEDED,
)
require.NoError(t.t, err)
}