package itest import ( "bytes" "context" "fmt" "strings" "github.com/btcsuite/btcd/txscript" "github.com/btcsuite/btcutil" "github.com/lightningnetwork/lnd/lnrpc" "github.com/lightningnetwork/lnd/lnrpc/walletrpc" "github.com/lightningnetwork/lnd/lntest" "github.com/lightningnetwork/lnd/lntest/wait" "github.com/lightningnetwork/lnd/lnwallet" "github.com/lightningnetwork/lnd/sweep" "github.com/stretchr/testify/require" ) // testCPFP ensures that the daemon can bump an unconfirmed transaction's fee // rate by broadcasting a Child-Pays-For-Parent (CPFP) transaction. // // TODO(wilmer): Add RBF case once btcd supports it. func testCPFP(net *lntest.NetworkHarness, t *harnessTest) { // Skip this test for neutrino, as it's not aware of mempool // transactions. if net.BackendCfg.Name() == lntest.NeutrinoBackendName { t.Skipf("skipping CPFP test for neutrino backend") } // We'll start the test by sending Alice some coins, which she'll use to // send to Bob. ctxb := context.Background() ctxt, _ := context.WithTimeout(ctxb, defaultTimeout) net.SendCoins(ctxt, t.t, btcutil.SatoshiPerBitcoin, net.Alice) // Create an address for Bob to send the coins to. addrReq := &lnrpc.NewAddressRequest{ Type: lnrpc.AddressType_WITNESS_PUBKEY_HASH, } ctxt, _ = context.WithTimeout(ctxb, defaultTimeout) resp, err := net.Bob.NewAddress(ctxt, addrReq) if err != nil { t.Fatalf("unable to get new address for bob: %v", err) } // Send the coins from Alice to Bob. We should expect a transaction to // be broadcast and seen in the mempool. sendReq := &lnrpc.SendCoinsRequest{ Addr: resp.Address, Amount: btcutil.SatoshiPerBitcoin, } ctxt, _ = context.WithTimeout(ctxb, defaultTimeout) if _, err = net.Alice.SendCoins(ctxt, sendReq); err != nil { t.Fatalf("unable to send coins to bob: %v", err) } txid, err := waitForTxInMempool(net.Miner.Client, minerMempoolTimeout) if err != nil { t.Fatalf("expected one mempool transaction: %v", err) } // We'll then extract the raw transaction from the mempool in order to // determine the index of Bob's output. tx, err := net.Miner.Client.GetRawTransaction(txid) if err != nil { t.Fatalf("unable to extract raw transaction from mempool: %v", err) } bobOutputIdx := -1 for i, txOut := range tx.MsgTx().TxOut { _, addrs, _, err := txscript.ExtractPkScriptAddrs( txOut.PkScript, net.Miner.ActiveNet, ) if err != nil { t.Fatalf("unable to extract address from pkScript=%x: "+ "%v", txOut.PkScript, err) } if addrs[0].String() == resp.Address { bobOutputIdx = i } } if bobOutputIdx == -1 { t.Fatalf("bob's output was not found within the transaction") } // Wait until bob has seen the tx and considers it as owned. op := &lnrpc.OutPoint{ TxidBytes: txid[:], OutputIndex: uint32(bobOutputIdx), } assertWalletUnspent(t, net.Bob, op) // We'll attempt to bump the fee of this transaction by performing a // CPFP from Alice's point of view. bumpFeeReq := &walletrpc.BumpFeeRequest{ Outpoint: op, SatPerVbyte: uint64( sweep.DefaultMaxFeeRate.FeePerKVByte() / 2000, ), } ctxt, _ = context.WithTimeout(ctxb, defaultTimeout) _, err = net.Bob.WalletKitClient.BumpFee(ctxt, bumpFeeReq) if err != nil { t.Fatalf("unable to bump fee: %v", err) } // We should now expect to see two transactions within the mempool, a // parent and its child. _, err = waitForNTxsInMempool(net.Miner.Client, 2, minerMempoolTimeout) if err != nil { t.Fatalf("expected two mempool transactions: %v", err) } // We should also expect to see the output being swept by the // UtxoSweeper. We'll ensure it's using the fee rate specified. pendingSweepsReq := &walletrpc.PendingSweepsRequest{} ctxt, _ = context.WithTimeout(ctxb, defaultTimeout) pendingSweepsResp, err := net.Bob.WalletKitClient.PendingSweeps( ctxt, pendingSweepsReq, ) if err != nil { t.Fatalf("unable to retrieve pending sweeps: %v", err) } if len(pendingSweepsResp.PendingSweeps) != 1 { t.Fatalf("expected to find %v pending sweep(s), found %v", 1, len(pendingSweepsResp.PendingSweeps)) } pendingSweep := pendingSweepsResp.PendingSweeps[0] if !bytes.Equal(pendingSweep.Outpoint.TxidBytes, op.TxidBytes) { t.Fatalf("expected output txid %x, got %x", op.TxidBytes, pendingSweep.Outpoint.TxidBytes) } if pendingSweep.Outpoint.OutputIndex != op.OutputIndex { t.Fatalf("expected output index %v, got %v", op.OutputIndex, pendingSweep.Outpoint.OutputIndex) } if pendingSweep.SatPerVbyte != bumpFeeReq.SatPerVbyte { t.Fatalf("expected sweep sat per vbyte %v, got %v", bumpFeeReq.SatPerVbyte, pendingSweep.SatPerVbyte) } // Mine a block to clean up the unconfirmed transactions. mineBlocks(t, net, 1, 2) // The input used to CPFP should no longer be pending. err = wait.NoError(func() error { req := &walletrpc.PendingSweepsRequest{} ctxt, _ = context.WithTimeout(ctxb, defaultTimeout) resp, err := net.Bob.WalletKitClient.PendingSweeps(ctxt, req) if err != nil { return fmt.Errorf("unable to retrieve bob's pending "+ "sweeps: %v", err) } if len(resp.PendingSweeps) != 0 { return fmt.Errorf("expected 0 pending sweeps, found %d", len(resp.PendingSweeps)) } return nil }, defaultTimeout) if err != nil { t.Fatalf(err.Error()) } } // testAnchorReservedValue tests that we won't allow sending transactions when // that would take the value we reserve for anchor fee bumping out of our // wallet. func testAnchorReservedValue(net *lntest.NetworkHarness, t *harnessTest) { // Start two nodes supporting anchor channels. args := commitTypeAnchors.Args() alice := net.NewNode(t.t, "Alice", args) defer shutdownAndAssert(net, t, alice) bob := net.NewNode(t.t, "Bob", args) defer shutdownAndAssert(net, t, bob) ctxb := context.Background() ctxt, _ := context.WithTimeout(ctxb, defaultTimeout) net.ConnectNodes(ctxt, t.t, alice, bob) // Send just enough coins for Alice to open a channel without a change // output. const ( chanAmt = 1000000 feeEst = 8000 ) ctxt, _ = context.WithTimeout(context.Background(), defaultTimeout) net.SendCoins(ctxt, t.t, chanAmt+feeEst, alice) // wallet, without a change output. This should not be allowed. resErr := lnwallet.ErrReservedValueInvalidated.Error() ctxt, _ = context.WithTimeout(context.Background(), defaultTimeout) _, err := net.OpenChannel( ctxt, alice, bob, lntest.OpenChannelParams{ Amt: chanAmt, }, ) if err == nil || !strings.Contains(err.Error(), resErr) { t.Fatalf("expected failure, got: %v", err) } // Alice opens a smaller channel. This works since it will have a // change output. ctxt, _ = context.WithTimeout(context.Background(), defaultTimeout) aliceChanPoint1 := openChannelAndAssert( ctxt, t, net, alice, bob, lntest.OpenChannelParams{ Amt: chanAmt / 4, }, ) // If Alice tries to open another anchor channel to Bob, Bob should not // reject it as he is not contributing any funds. aliceChanPoint2 := openChannelAndAssert( ctxt, t, net, alice, bob, lntest.OpenChannelParams{ Amt: chanAmt / 4, }, ) // Similarly, if Alice tries to open a legacy channel to Bob, Bob should // not reject it as he is not contributing any funds. We'll restart Bob // to remove his support for anchors. err = net.RestartNode(bob, nil) require.NoError(t.t, err) ctxt, _ = context.WithTimeout(ctxb, defaultTimeout) aliceChanPoint3 := openChannelAndAssert( ctxt, t, net, alice, bob, lntest.OpenChannelParams{ Amt: chanAmt / 4, }, ) chanPoints := []*lnrpc.ChannelPoint{ aliceChanPoint1, aliceChanPoint2, aliceChanPoint3, } for _, chanPoint := range chanPoints { ctxt, _ = context.WithTimeout(ctxb, defaultTimeout) err = alice.WaitForNetworkChannelOpen(ctxt, chanPoint) require.NoError(t.t, err) ctxt, _ = context.WithTimeout(ctxb, defaultTimeout) err = bob.WaitForNetworkChannelOpen(ctxt, chanPoint) require.NoError(t.t, err) } // Alice tries to send all coins to an internal address. This is // allowed, since the final wallet balance will still be above the // reserved value. addrReq := &lnrpc.NewAddressRequest{ Type: lnrpc.AddressType_WITNESS_PUBKEY_HASH, } ctxt, _ = context.WithTimeout(ctxb, defaultTimeout) resp, err := alice.NewAddress(ctxt, addrReq) require.NoError(t.t, err) sweepReq := &lnrpc.SendCoinsRequest{ Addr: resp.Address, SendAll: true, } ctxt, _ = context.WithTimeout(ctxb, defaultTimeout) _, err = alice.SendCoins(ctxt, sweepReq) require.NoError(t.t, err) block := mineBlocks(t, net, 1, 1)[0] // The sweep transaction should have exactly one input, the change from // the previous SendCoins call. sweepTx := block.Transactions[1] if len(sweepTx.TxIn) != 1 { t.Fatalf("expected 1 inputs instead have %v", len(sweepTx.TxIn)) } // It should have a single output. if len(sweepTx.TxOut) != 1 { t.Fatalf("expected 1 output instead have %v", len(sweepTx.TxOut)) } // Wait for Alice to see her balance as confirmed. waitForConfirmedBalance := func() int64 { var balance int64 err := wait.NoError(func() error { req := &lnrpc.WalletBalanceRequest{} ctxt, _ = context.WithTimeout(ctxb, defaultTimeout) resp, err := alice.WalletBalance(ctxt, req) if err != nil { return err } if resp.TotalBalance == 0 { return fmt.Errorf("no balance") } if resp.UnconfirmedBalance > 0 { return fmt.Errorf("unconfirmed balance") } balance = resp.TotalBalance return nil }, defaultTimeout) require.NoError(t.t, err) return balance } _ = waitForConfirmedBalance() // Alice tries to send all funds to an external address, the reserved // value must stay in her wallet. minerAddr, err := net.Miner.NewAddress() require.NoError(t.t, err) sweepReq = &lnrpc.SendCoinsRequest{ Addr: minerAddr.String(), SendAll: true, } ctxt, _ = context.WithTimeout(ctxb, defaultTimeout) _, err = alice.SendCoins(ctxt, sweepReq) require.NoError(t.t, err) // We'll mine a block which should include the sweep transaction we // generated above. block = mineBlocks(t, net, 1, 1)[0] // The sweep transaction should have exactly one inputs as we only had // the the single output from above in the wallet. sweepTx = block.Transactions[1] if len(sweepTx.TxIn) != 1 { t.Fatalf("expected 1 inputs instead have %v", len(sweepTx.TxIn)) } // It should have two outputs, one being the miner address, the other // one being the reserve going back to our wallet. if len(sweepTx.TxOut) != 2 { t.Fatalf("expected 2 outputs instead have %v", len(sweepTx.TxOut)) } // The reserved value is now back in Alice's wallet. aliceBalance := waitForConfirmedBalance() // Alice closes channel, should now be allowed to send everything to an // external address. for _, chanPoint := range chanPoints { closeChannelAndAssert(ctxt, t, net, alice, chanPoint, false) } newBalance := waitForConfirmedBalance() if newBalance <= aliceBalance { t.Fatalf("Alice's balance did not increase after channel close") } // We'll wait for the balance to reflect that the channel has been // closed and the funds are in the wallet. sweepReq = &lnrpc.SendCoinsRequest{ Addr: minerAddr.String(), SendAll: true, } ctxt, _ = context.WithTimeout(ctxb, defaultTimeout) _, err = alice.SendCoins(ctxt, sweepReq) require.NoError(t.t, err) // We'll mine a block which should include the sweep transaction we // generated above. block = mineBlocks(t, net, 1, 1)[0] // The sweep transaction should have four inputs, the change output from // the previous sweep, and the outputs from the coop closed channels. sweepTx = block.Transactions[1] if len(sweepTx.TxIn) != 4 { t.Fatalf("expected 4 inputs instead have %v", len(sweepTx.TxIn)) } // It should have a single output. if len(sweepTx.TxOut) != 1 { t.Fatalf("expected 1 output instead have %v", len(sweepTx.TxOut)) } }